JP2016010805A - Welding method of heat transfer copper fin for metal cask and metal cask with heat transfer copper fin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a welding method of heat transfer copper fin for metal cask excellent in welding property of foreign matter joint between copper and steel.SOLUTION: A welding method of a heat transfer copper fin for a metal cask is characterized in that, when the minimum distance from a molten bottom part of the heat transfer copper fin side to a weld bead surface is set as a throat thickness of a welded part, a wire weld cross-section is determined from a wire feeding speed or the wire feeding speed and a wire diameter, and a prescribed welding speed so that the throat thickness with a predetermined size or greater is formed, a CuSi wire is used for a weld line at every path to be welded from a weld starting position to an ending position of each fillet joint part and weld construction is performed at every one path by a composite welding of preceding TIG and subsequent MIG or MIG welding.

Description

  The present invention relates to a method for welding a heat transfer copper fin for a metal cask and a metal cask with a heat transfer copper fin, and in particular, transports or stores or transports and stores spent fuel generated from a nuclear power plant, etc. The present invention relates to a welding method for heat transfer copper fins for metal cask and a metal cask with heat transfer copper fins suitable for welding copper heat transfer fins directly to the inner and outer cylinders.

  In general, a plurality of fuels used for a certain period in a nuclear power plant nuclear reactor are taken out of the nuclear reactor and temporarily stored in a spent fuel cooling pool or the like. Spent fuel that has been cooled in the spent fuel cooling pool for a specified period of time is stored in a radioactive material storage container called a metal cask to be used as a resource, and then transported to an intermediate storage facility until it is reprocessed at the reprocessing facility. Stored.

  A metal cask that transports and stores spent fuel assemblies consists of an inner cylinder (also referred to as an inner cylinder container, a container body, or a trunk body) that stores spent fuel, and an outer cylinder and an inner cylinder that absorb impact from the outside. It has a plurality of lids to be sealed.

  Since spent fuel contains a high level of radioactive material, it generates decay heat, so the decay heat generated from the spent fuel assembly is transferred between the inner and outer cylinders between the inner and outer cylinders. A plurality of heat transfer fins are provided in order to escape to the outside, and the plurality of heat transfer fins are welded to the inner cylinder and the outer cylinder, respectively.

  Usually, carbon steel materials and stainless steel materials with good performance such as rigidity and shielding properties are used as the material of the inner cylinder and the outer cylinder, while copper materials with good heat conduction are mainly used as the material of the heat transfer fins. Moreover, the copper clad steel material etc. which joined two types of metals previously are also used.

  For example, Patent Documents 1 to 5 disclose known techniques for welding heat transfer fins to the inner and outer surfaces of the metal cask described above.

  Patent Document 1 describes a method for manufacturing a metal container. A welding process for generating a MIG arc from a pure copper MIG wire, and a plasma arc from a plasma electrode arranged coaxially so as to surround the MIG arc are generated. The welding process is performed in parallel, and in the MIG welding process and the plasma welding process, the angle formed by the copper heat transfer fin and the horizontal plane is 15 to 20 degrees, and the angle formed by the heat transfer fin and the carbon steel inner cylinder. It is disclosed that the MIG arc and the plasma arc are generated in a downward direction by arranging them at 75 degrees or more.

  Patent Document 2 describes a welding method. A welding process of welding a steel base material and a copper base material requiring heat treatment after welding by a welding means such as a MIG torch; Heating (including melting) the welding bead generated in the welding process by heating means such as an arc welding torch, a high-frequency coil, or a laser disposed at a rear position away from the welding heat of the steel base material. A heat treatment step of heat-treating to the affected part, and further, before the welding step, by a heating means such as a TIG torch, a YAG laser, a high-frequency coil, etc. arranged at a front position ahead of the welding means by a predetermined distance, It is disclosed that the copper base material having a high thermal conductivity is preheated before the welding process.

  Patent Document 3 describes a method for welding copper or copper alloy, which combines a non-consumable electrode and a consumable electrode, and alternately supplies a welding current to a preceding non-consumable electrode and a subsequent consumable electrode, and It is disclosed that welding is performed while keeping the distance between the electrode and the consumable electrode at a distance that does not cause poor fusion beads.

  Patent Document 4 describes a metal cask for a radioactive material, and includes a heat transfer fin that extends radially outward from a trunk body and transfers heat to an outer cylinder. The heat transfer fin joins two types of metal plates. And one metal of the clad material is made of the same metal material for the body and outer cylinder, and the other is made of a good heat transfer material with good heat conduction, and the body ( And / or an outer tube) and a clad portion of the same kind of metal are directly welded.

  Further, Patent Document 5 describes a radioactive substance storage container, in which parallel portions are formed at both ends of the copper heat transfer fins, and the parallel portions are formed along the outer peripheral surface of the container main body and the inner peripheral surface of the outer cylinder. It is disclosed that the outer peripheral surface of the container body and the inner peripheral surface of the outer cylinder and the parallel tips of the heat transfer fins are welded by MIG welding or MIG brazing using a copper alloy wire.

JP 2009-178727 A JP 2002-361469 A JP 58-3791 A JP 2007-205931 A JP 2008-082906 A

  However, in Patent Document 1 described above, since the MIG arc and the plasma arc are generated almost coaxially, the electromagnetic forces acting on both arcs cancel each other, but the MIG wire (consumable electrode) and the plasma electrode (non-consumable) Since the polarity of the electrode is positive (plus) and the base metal side is negative (minus), the plasma electrode is easily consumed and damaged, so long members with long weld lines that require long-term operation It is not suitable for welding, and if the plasma electrode is consumed during welding, it may change to unstable arc behavior and adversely affect weld bead formation, leading to poor welding. In addition, pure copper is a material with high thermal conductivity. However, because dissimilar welding of copper and steel is not compatible and difficult to dissolve, the copper / steel joint is made of pure copper MIG wire. If the penetration on the steel side becomes deeper after welding, weld cracks (solidification cracks) are likely to occur.

  Moreover, in patent document 2, since it is the structure which provides heating means, such as an arc welding torch, a high frequency coil, or a laser, in the back position and / or the front position of this welding means, while an apparatus enlarges, The part which cannot be welded will generate | occur | produce by interference with a welding target object, etc. When a high frequency coil that generates magnetism is provided, the arc behavior of the welding means may become unstable due to electromagnetic force, which may adversely affect weld bead formation. On the other hand, when a laser is used, the copper base material cannot be heated sufficiently because the reflectance of light is high with respect to the copper base material.

  In Patent Document 3, in order to avoid interference between arcs, the current on the non-consumable electrode (TIG) side and the current on the consumable electrode (MIG) side are alternately switched and supplied. For this reason, when the TIG arc is generated, the MIG arc is extinguished, and conversely, during the generation of the MIG arc, the TIG arc is extinguished and the copper or copper alloy base material is welded. Therefore, it is considered difficult to significantly improve the welding efficiency. Moreover, a welding target object is welding between copper materials or between copper alloy materials, and about the dissimilar material welding of a copper material and steel materials, it is not applied outside the object, and neither description nor suggestion is made.

In Patent Document 4, since it is configured so as to weld the steel portion and the steel body or barrel of copper clad steel, although MAG welding and CO ₂ welding of steel materials to each other becomes possible construction Since the copper clad steel material is used for the heat transfer fin, there is a problem that the manufacturing cost is high and the weight is increased. In addition, since the copper clad steel material has a thin copper side, there is a limit to heat removal performance, so it is not suitable for heat transfer fins that require higher heat removal performance.

  Furthermore, in patent document 5, while using a copper plate with a wide plate | board width, it is a structure which requires processes, such as bending molding for providing a parallel part in the both ends of a copper plate width direction, and there exists a problem that manufacturing cost becomes high. is there. In addition, the parallel part is brought into close contact with the outer peripheral surface of the container body and the inner peripheral surface of the outer cylinder to form a lap fillet joint, and the lap fillet joint is subjected to MIG welding or MIG brazing. The amount of heat input is required, and further, a dent such as an undercut that is likely to occur at the weld bead toe on the copper side may lead to a lack of throat thickness or an insufficient effective cross-sectional area of the weld.

  The present invention has been made in view of the above points, and the object of the present invention is to provide a method for welding a heat transfer copper fin for a metal cask excellent in weldability of a dissimilar joint between copper and steel, and the heat transfer copper fin attached. It is to provide a metal cask.

  In order to achieve the above object, a welding method for heat transfer copper fins for a metal cask according to the present invention includes a steel inner cylinder that houses an assembly of spent fuel having a radioactive substance, and a coaxial outer shaft of the inner cylinder. When welding a plurality of copper heat transfer copper fins that are inclined and arranged at substantially equal intervals in the circumferential direction between the steel outer cylinders arranged in a shape, in the longitudinal direction of the outer surface of the inner cylinder made of steel The inner cylinder side wide-angle inclined fillet joints formed by abutting the one end surface portions of the predetermined number of heat transfer copper fins at substantially equal intervals, or the predetermined number of the longitudinal ends of the inner surface of the outer cylinder Each of the other end face portions of the heat transfer copper fins is formed by abutting each other at substantially equal intervals, and each of the fillet joint portions having a wide-angle inclination on the outer tube side, or formed on both surfaces of the inner tube and the outer tube, respectively. Each fillet joint is welded by composite welding of preceding TIG and subsequent MIG or MIG welding. A method for welding a heat transfer copper fin for a metal cask, wherein the minimum distance from the molten bottom on the heat transfer copper fin side to the surface of the weld bead is the throat thickness of the weld, and the throat thickness is equal to or greater than a predetermined size. The wire welding cross-sectional area is determined from the wire feed speed or the wire feed speed and the wire diameter and a predetermined welding speed so as to be formed, and welding should be performed from the welding start position to the end position of each fillet joint. It is characterized in that a CuSi wire is used for the welding line for each pass, and welding is performed one pass at a time by composite welding of the preceding TIG and subsequent MIG or by the MIG welding.

  Further, in order to achieve the above object, the welding method for heat transfer copper fins for metal cask according to the present invention includes a steel inner cylinder that houses an assembly of spent fuel having a radioactive substance, and an outer side of the inner cylinder. When welding a plurality of copper heat transfer copper fins inclined at substantially equal intervals in the circumferential direction between the steel outer cylinder and the steel outer cylinder, the length of the outer surface of the inner cylinder made of steel is welded A predetermined number of heat transfer copper fins in the direction of the inner cylinder side wide angle inclined fillet joints formed by abutting one end surface part of the heat transfer copper fins at substantially equal intervals, or a predetermined number of longitudinal direction of the inner surface of the outer cylinder Each of the other end face portions of the heat transfer copper fin is abutted at substantially equal intervals, and is formed on each of the outer tube side wide-angle inclined fillet joint portions, or on both surfaces of the inner tube and the outer tube, respectively. Welded to each fillet joint part by composite welding of preceding TIG and subsequent MIG or MIG welding A method for welding heat transfer copper fins for metal casks to be processed, wherein the throat thickness is a predetermined size when the minimum distance from the molten bottom on the heat transfer copper fin side to the weld bead surface is the throat thickness of the weld. A wire welding amount determining step of determining a wire welding cross-sectional area from the wire feeding speed or the wire feeding speed and the wire diameter and a predetermined welding speed so as to be formed more than the predetermined length, and a predetermined number of sheets in the longitudinal direction of the outer surface of the inner cylinder After the end face portions of the heat transfer copper fins are butted at substantially equal intervals to form N fillet joint portions having a wide angle slope, CuSi wire is used to perform composite welding of the preceding TIG and the subsequent MIG or by the MIG welding. A first welding process on the inner cylinder side for welding one pass at a time to each fillet joint on the inner cylinder side, and after the end of welding on the inner cylinder side or the end of welding on the inner cylinder side and inspection of the welded portion After finish, before The outer cylinder is arranged on the outer peripheral side of the heat transfer copper fin, and the other end face portions of the predetermined number of heat transfer copper fins are butted in the longitudinal direction of the inner surface of the outer cylinder to form N wide fillet joint portions After forming, second weld on the outer cylinder side that uses the CuSi wire and welds one pass at a time to each fillet joint on the outer cylinder side by composite welding of the preceding TIG and subsequent MIG or the MIG welding. And a process.

  Further, in order to achieve the above object, the welding method for heat transfer copper fins for metal cask according to the present invention includes a steel inner cylinder that houses an assembly of spent fuel having a radioactive substance, and an outer side of the inner cylinder. When welding a plurality of copper heat transfer copper fins inclined at substantially equal intervals in the circumferential direction between the steel outer cylinder and the steel outer cylinder, the length of the outer surface of the inner cylinder made of steel is welded A predetermined number of heat transfer copper fins in the direction of the inner cylinder side wide angle inclined fillet joints formed by abutting one end surface part of the heat transfer copper fins at substantially equal intervals, or a predetermined number of longitudinal direction of the inner surface of the outer cylinder Each of the other end face portions of the heat transfer copper fins is formed by abutting each other at substantially equal intervals, respectively, on each outer joint side wide-angle inclined fillet joint portion, or on both surfaces of the inner and outer tubes. Welding work to each fillet joint by composite welding of preceding TIG and subsequent MIG or MIG welding A heat transfer copper fin welding method for a metal cask, wherein the throat thickness is a predetermined size when the minimum distance from the molten bottom on the heat transfer copper fin side to the weld bead surface is the throat thickness of the weld. A wire welding amount determining step for determining a wire welding cross-sectional area from the wire feeding speed or the wire feeding speed and the wire diameter and a predetermined welding speed as formed above, and a predetermined number of the above in the longitudinal direction of the outer surface of the inner cylinder After forming N portions of the wide-angle inclined fillet joints by butting one end face portions of the heat transfer copper fins at substantially equal intervals, CuSi wire is used to perform the composite welding of the preceding TIG and the subsequent MIG or the MIG welding. A step of welding one pass at a time to each fillet joint portion on the inner cylinder side, or a wide angle inclination by abutting a predetermined number of one end surface portions of the heat transfer copper fins at substantially equal intervals in the longitudinal direction of the inner cylinder outer surface of After forming N fillet joints, the N fillet joints are divided in advance, welded to the fillet joints of the divided units, and the welds are inspected. The step of repeating welding and inspection of the fillet joint portion, or dividing a predetermined number of the heat transfer copper fins in advance, and pushing one end surface portion of the heat transfer copper fin of the divided unit against the outer surface of the inner cylinder In addition, after forming the fillet joint part, welding is performed, and the inner cylinder side first is performed which repeats the formation, welding, and inspection of the fillet joint part so as to inspect the weld part. The outer cylinder is disposed on the outer peripheral side of the heat transfer copper fin after the welding process of the inner cylinder side or after the end of welding on the inner cylinder side and the end of the inspection of the welded portion, and the inner surface of the outer cylinder The other end faces of the heat transfer copper fins of a predetermined number in the longitudinal direction After the N-parts of the wide angle slope are formed by butting the parts, the CuSi wire is used at the time of welding, and each fillet on the outer cylinder side is obtained by composite welding of the preceding TIG and the subsequent MIG or the MIG welding. After the step of welding one pass to the joint, or after forming N wide-angle inclined fillet joints by abutting each other end face of the heat transfer copper fin in the longitudinal direction of the inner surface of the outer cylinder The N fillet joints are divided in advance and welded to the fillet joints of the divided units, and the fillet joints are welded and inspected so as to inspect the welds. The process of repeating, or, instead of the outer cylinder, a plate-like outer cylinder plate that has been divided into a plurality of sheets is used, and the other of the heat transfer copper fins corresponding to the longitudinal direction of the inner surface of the plate-like outer cylinder plate A wide-angle inclined fillet joint is formed by abutting the end faces. Then, welding is applied to the fillet joint portion, and the second step on the outer cylinder side that performs any one of the steps of repeating the formation, welding, and inspection of the fillet joint portion so as to inspect the weld portion. And a welding process.

  Furthermore, in order to achieve the above object, the metal cask with the heat transfer copper fin according to the present invention has a steel inner cylinder that houses an assembly of spent fuel having a radioactive substance, and a coaxial shape outside the inner cylinder. A steel outer cylinder, and a plurality of copper heat transfer copper fins inclined at substantially equal intervals in the circumferential direction between the inner cylinder and the outer cylinder, the steel inner cylinder Each inner joint side wide-angle inclined fillet joint portion formed by abutting one end face portions of the heat transfer copper fins at a substantially equal interval in the longitudinal direction of the outer surface, or the longitudinal direction of the inner surface of the outer tube Each of the other end face portions of the heat transfer copper fins of a predetermined number of each at a substantially equal interval, and each of the wide-angle inclined fillet joint portions on the outer cylinder side, or both surfaces of the inner cylinder and the outer cylinder The fillet joints formed in each of the above are connected by composite welding of preceding TIG and subsequent MIG or MIG welding. A metal cask with heat transfer copper fins formed by welding one pass at a time, using CuSi wire, each welded one pass at a time by composite welding of the preceding TIG and subsequent MIG or the MIG welding At the welded portion of the fillet joint portion, at least the throat thickness L is formed to be equal to or greater than the plate thickness T1 of the heat transfer copper fin, and the steel inner tube side or the outer tube side or the inner tube and the outer tube The penetration depth c on both sides is formed in the range of 0.05 ≦ c ≦ 4 mm.

  According to the present invention, the weldability of a dissimilar joint of copper and steel can be made excellent, and it is very effective for the welding method of the heat transfer copper fin for metal cask and the metal cask with heat transfer copper fin. It is.

It is a perspective view which shows the structure of the metal cask with a heat-transfer copper fin concerning Example 1 of this invention. It is a fragmentary perspective view which shows the joint welding structure which expanded the A section in FIG. It is a flowchart which shows the outline | summary of the procedure of the welding method of the heat transfer copper fin for metal casks concerning Example 1 of this invention. It is a flowchart which shows the other procedure outline | summary of the welding method of the heat transfer copper fin for metal casks concerning Example 1 of this invention. It is a fragmentary perspective view which shows the shape of the fillet joint part of the inner cylinder outer surface and the end surface part of a heat-transfer copper fin in the metal cask with a heat-transfer copper fin concerning Example 1 of this invention. It is a fragmentary perspective view which shows the shape of the welding part welded to the fillet joint part by the side of the inner cylinder shown in FIG. It is a fragmentary perspective view which shows the shape of the fillet joint part which should be welded with the outer cylinder outer surface and the other end surface part of a heat-transfer copper fin in the metal cask with a heat-transfer copper fin concerning Example 1 of this invention. It is a fragmentary perspective view which shows the shape of the welding part welded to the fillet joint part by the side of the outer cylinder shown in FIG. It is a flowchart which shows the further procedure outline | summary of the welding method of the heat transfer copper fin for metal casks concerning Example 1 of this invention. It is a fragmentary perspective view which shows the shape of the fillet joint part of the inner cylinder outer surface in the metal cask with a heat-transfer copper fin concerning Example 1 of this invention, and the end surface part of one heat-transfer copper fin. It is a fragmentary perspective view which shows the shape of the welding part welded to the fillet joint part by the side of the inner cylinder shown in FIG. It is a fragmentary perspective view which shows the shape of the fillet joint part of the inner cylinder outer surface in the metal cask with a heat-transfer copper fin concerning Example 1 of this invention, and the end surface part of two heat-transfer copper fins. It is a fragmentary perspective view which shows the shape of the welding part welded to the fillet joint part by the side of the inner cylinder shown in FIG. It is a fragmentary perspective view which shows the shape of the fillet joint part of the plate-shaped outer cylinder board outer surface in the metal cask with a heat-transfer copper fin concerning Example 1 of this invention, and the other end surface part of a heat-transfer copper fin. It is a fragmentary perspective view which shows the shape of the welding part welded to the fillet joint part by the side of the plate-shaped outer cylinder board shown in FIG. It is a fragmentary perspective view which shows the shape of the fillet joint part of the plate-shaped outer cylinder board outer surface in the metal cask with a heat transfer copper fin concerning Example 1 of this invention, and the other end surface part of two heat transfer copper fins. is there. It is a fragmentary perspective view which shows the shape of the welding part welded to the fillet joint part by the side of the plate-shaped outer cylinder board | plate shown in FIG. It is a figure before forming a molten pool with a TIG arc and a MIG arc, showing a schematic structure and a torch arrangement of an integral structure TIG-MIG welding torch according to Example 1 of the present invention. It is a figure which shows the state which formed the molten pool by the TIG arc and the MIG arc from the state of FIG. It is a perspective view which shows schematic structure and torch arrangement | positioning of the MIG welding torch concerning Example 2 of this invention. It is a figure which shows the end surface shape and torch arrangement | positioning of the heat-transfer copper fin in MIT welding concerning Example 2 of this invention. It is a figure which shows the end surface shape and torch arrangement | positioning of a heat-transfer copper fin in the composite welding of the preceding TIG and subsequent MIG concerning Example 1 of this invention. It is a welding apparatus of the heat transfer copper fin for metal casks concerning Example 3 of this invention, and is a front view which shows the structure which arrange | positioned the TIG-MIG welding torch and the guide roller at the front-end | tip part of a long arm. It is a left view of the structure shown in FIG. It is a characteristic view which shows the relationship between the wire feed speed concerning this invention, a wire welding cross-sectional area, and a throat thickness. It is a characteristic view which shows the relationship between the shift amount of the torch position in MIG welding of the end surface flat surface joint of a copper plate concerning this invention, and an end surface inclined surface joint, and the throat thickness and bead width of a welding part. It is a figure which shows the weld bead external appearance of the end face flat surface joint, and a weld cross-section photograph when changing the shift amount S2 (the second distance S2) of the torch position (wire position) according to the present invention. It is a characteristic view which shows the relationship between the penetration depth when the CuSi wire is directly welded to the carbon steel surface according to the present invention and the dilution rate on the steel side. It is a characteristic view which shows the quality evaluation result and appropriate condition area | region of a weld part when changing the gap of the fillet joint part concerning this invention, and the amount of shifts of a torch position, and performing the TIG-MIG composite welding test. It is a figure which shows the typical welding cross-section photograph of the welded part which carried out TIG-MIG compound welding concerning this invention. FIG. 4 is a characteristic diagram showing the relationship between the throat thickness and the bead vertical height of the weld according to the present invention, in which each corresponding value is extracted from the test data shown in Table 2 and graphed. It is a fragmentary sectional view which shows the example which builds up the welding part when it determines with disqualification in one Example of this invention, and its vicinity. It is a characteristic view which shows the relationship between the bead vertical height concerning this invention, and the penetration depth. It is a characteristic view which shows the relationship between the throat thickness and penetration depth of the weld part concerning this invention. It is a characteristic view which shows the relationship between the penetration depth concerning this invention, and the tensile load of a welded joint. It is a perspective view which shows the example using the slit light cutting sensor which detects the weld line position of the fillet joint part which should be welded concerning Example 4 of this invention, and its position shift. It is a figure which shows the alignment of the torch position (wire position) performed before welding concerning Example 4 of this invention, and the alignment of the origin position coordinate on the sensor side. It is a figure which shows an example of the image monitor concerning Example 4 of this invention. It is a perspective view which shows the other example using the slit light cutting sensor which detects the weld line position of the fillet joint part which should be welded concerning Example 4 of this invention, and its position shift. It is a welding apparatus of the heat transfer copper fin for metal casks concerning Example 5 of this invention, and is a front view which shows the structure which arrange | positioned the TIG-MIG welding torch and the guide roller at the front-end | tip part of a long arm. It is a figure which shows the distance sensor which measures the distance to the member surface concerning this invention, and a distance change. It is a front view of the composition which shows the example which arranged the TIG-MIG welding torch and the distance sensor in the tip part of the long arm concerning the present invention. It is a characteristic view which shows the relationship between the shift amount of the torch position, TIG current / voltage, and MIG current / voltage in the composite welding of the preceding TIG and the succeeding MIG according to the present invention. It is a figure which shows the detection of the bead vertical height of the welding part by the slit light cutting sensor concerning Example 6 of this invention. It is an example of the image monitor concerning Example 6 of this invention, and is a figure which shows the detection of the magnitude | size (depth) of an undercut by a slit light cutting sensor. It is a figure which shows the detection of the bead vertical height of the welding part by the manually operated dimension measuring device concerning Example 7 of this invention.

  Hereinafter, based on the illustrated embodiment, a welding method for a heat transfer copper fin for a metal cask of the present invention and its welding apparatus will be described. In each figure, the same symbols are used for the same components.

  FIG. 1 shows a structure of a metal cask with a heat transfer copper fin according to the present embodiment, and FIG. 2 shows a welded structure in which a portion A in FIG. 1 is enlarged.

  In the figure, an inner cylinder 1 is a container for storing an assembly of a plurality of spent fuels (not shown) having radioactive materials therein, and made of steel such as carbon steel having high strength. It has been. On the outside of the inner cylinder 1, a steel outer cylinder 2 made of the same material as the inner cylinder 1 is arranged coaxially so as to surround the inner cylinder 1 (the strength and rigidity of the entire metal cask is high in strength). It is sufficiently secured by a plurality of lids (not shown) for sealing the inner cylinder 1 and the outer cylinder 2 of steel thick plates and the container formed by these. Between the outer surface of the inner cylinder 1 and the inner surface of the outer cylinder 2, dozens of heat transfer copper fins 3 (in a predetermined number called N) are inclined and arranged at substantially equal intervals in the circumferential direction. .

  These N heat transfer copper fins 3 are made of a copper plate made of copper such as pure copper having a high thermal conductivity. By using the copper heat transfer copper fins 3, collapse occurs from the spent fuel assembly. While the heat removal performance for releasing heat to the outside of the inner cylinder 1 and the outer cylinder 2 can be enhanced, it can also contribute to weight reduction and cost reduction.

  As shown in FIG. 2, an inner welded portion (weld bead and its weld cross section) welded by each fillet joint portion 5 on the inner cylinder 1 side is provided on each end surface portion of the N heat transfer copper fins 3. ) 7 is formed, and an outer welded portion 10 (weld bead and its weld cross section) welded by each fillet joint portion 8 on the outer tube 2 side is formed on each other end surface portion. Yes. The inner welded portion 7 and the outer welded portion 10 of the heat transfer copper fin 3 are not particularly required in strength, but it is necessary to ensure high reliability due to the nature of the material to be stored and stored.

  The angle θ1 between the inner cylinder 1 and the heat transfer copper fin 3 of each fillet joint portion 5 and 8 of the N heat transfer copper fins 3 to be welded, and the outer cylinder 2 and the heat transfer copper fin 3 is determined by the inner cylinder. 1 and the inner surface of the outer tube 2 or both surfaces of the inner tube 1 and the outer tube 2 are inclined at a wide angle in a range of θ1 = 120 degrees ± 15 degrees (105 ≦ θ1 ≦ 135 degrees). .

  Each space 4 adjacent to the N heat transfer copper fins 3 is a place where a resin (not shown) such as a resin material is filled and arranged. These resins are substances that shield radiation emitted from the assembly of spent fuel in a normal line, and after welding, the resin is placed in each space along the inclined surface of the N heat transfer copper fins 3. 4 is filled in each. By arranging the heat transfer copper fins 3 to be inclined at a wide angle, workability during welding is facilitated, and radiation is shielded by the inclined arrangement of the resin filled along the inclined surfaces of the heat transfer copper fins 3. Performance can be increased.

  A method for welding both end portions of the heat transfer copper fin 3 in this embodiment to both surfaces of the inner cylinder 1 and the outer cylinder 2 will be described below.

  FIG. 3 is a flowchart showing an example of the welding procedure outline of the heat transfer copper fin for metal cask according to the present embodiment, and FIG. 4 shows an example of the outline of the welding procedure of heat transfer copper fin for another metal cask. It is a flowchart which shows an example. The main difference between the flowcharts shown in FIGS. 3 and 4 is that the contents of the first welding process 103 on the inner cylinder 1 side and the welding process 110 on the outer cylinder 2 side are welded at N locations on the inner cylinder 1 side. The repeated welding step 105 and the repeated welding step 112 of welding N places on the outer cylinder 2 side, the welding and inspection repeated welding step 106 on the inner cylinder 1 side and the minor unit on the outer cylinder 2 side, and That is, the inspection is repeatedly divided into welding steps 113.

  For example, as shown in FIG. 3, in the welding procedure (No. 1) 99 of the heat transfer copper fin 3, a wire welding sectional area determining step 102 for determining the wire welding sectional area Aw before welding, and a predetermined number (N). After the end face portions of the heat transfer copper fins 3 are butted to the inner cylinder 1 side to form N fillet joint portions 5, the N fillet joint portions 5-1, 5-2... 5 After completion of the first welding process 103 on the inner cylinder 1 side to be repeatedly welded to -N and the repeated welding process 105 of N-point welding, and the inspection process 107 of the welding quality on the inner cylinder 1 side performed thereafter, N sheets After the other end face portions of the heat transfer copper fins 3 are butted against the outer cylinder 2 side to form N fillet joint portions 8, the N fillet joint portions 8-1, 8-2. A second welding step 110 on the outer cylinder 2 side that is repeatedly welded to 8-N, and a repeated welding step 112 of welding at N locations; It has.

  And after forming N fillet joint parts 8 at the N fillet joint parts 8-1, 8-2... 8 -N, one pass is repeatedly welded (continuous welding). Temporary assembly work and welding work of the meat joint portion can be performed efficiently.

  On the other hand, as shown in FIG. 4, in the welding procedure (part 2) 100 of the heat transfer copper fin 3, the inner cylinder 1 side to be performed after the wire welding sectional area determining step 102 for determining the wire welding sectional area Aw before welding. In the first welding step 103, N places of welding that are repeatedly welded (continuous welding) one by one to the N fillet joint parts 5-1, 5-2,..., 5-N on the inner cylinder 1 side. Welding and inspection in a small number of units that repeat both welding and inspection so that the welding process 105 and the fillet joint portion divided into about 1 to 5 places are welded and the welded portion after the welding is inspected. And the repeated welding process 106.

  For example, a predetermined number (N) of heat transfer copper fins 3 are attached to the outer surface of the inner cylinder 1 in the repeated welding process 106 of welding and inspection in a small number of units that are divided into a small number of units and repeat welding and inspection. After the N fillet joints are formed, the N fillet joints 5-1, 5-2,..., 5-N are divided into about 1 to 5 places in advance, and the divided 1 to 5 places The fillet joint portions 5-1 to 5-5 are welded one pass at a time, and the weld and inspection of the fillet joint portions are repeated so as to inspect the weld portions.

  On the other hand, in the second welding process 110 on the outer cylinder 2 side, as in the repeated welding process 105 of N weldings on the inner cylinder 1 side and the repeated welding process 106 of welding and inspection in a small number unit, N-section fillet joints 8-1, 8-2,..., 8-N are repeatedly welded (continuous welding) one by one, and the N-part welding repeated welding process 112 is divided into about 1 to 5 places. In addition to welding one pass at a time to the fillet joint portion, the welding portion is divided into a welding process and a repeated welding step 113 of a small number of units that repeat both welding and inspection operations. The repeated welding process 113 of the minority unit that repeats welding and inspection on the outer cylinder 2 side is the same as the case of the inner cylinder 2 side, and N fillet joints formed on the outer cylinder 2 side are the same. 8-1, 8-2 ... 8-N is divided into about 1 to 5 places in advance and welded to the divided 1 to 5 fillet joints 8-1 to 8-5 one by one. The welding and inspection of the fillet joint are repeated so as to inspect the weld.

  In this way, by selecting one of two types of operations (continuous welding or repetition of welding and inspection), it is possible to improve work efficiency with priority on welding or improvement in welding quality with priority on inspection.

  Next, after the end of the first welding process 103 on the inner cylinder 1 side and the repeated welding process 105 of N places on the inner cylinder 1 side, or the first welding process 103 on the inner cylinder 1 side, the inner cylinder 1 side After the completion of the N welding repeated welding process 105, the second welding process 110 on the outer cylinder 2 side, and the N welding repeated welding process 112 on the outer cylinder 2 side, the inner cylinder 1 side for inspecting the welding quality In the inspection step 107 and the inspection step 114 on the outer cylinder 2 side, the quality of each welded portion is inspected, and the repaired welding steps 109 and 116 for repairing the welded portion that has failed the inspection and the vicinity thereof are repaired. I have.

  Further, in the inspection process 117 on the inner cylinder 1 side and the inspection process 120 on the outer cylinder 2 side when both the welding and inspection operations are repeatedly performed, whether or not the weld bead is well formed in the corresponding welded portion, Inspection / confirmation of welding quality, such as whether or not there are defects such as cracks and undercuts, and whether or not the throat thickness L and penetration depth c are satisfied. When the inspection process 117 on the inner cylinder 1 side and the inspection process 120 on the outer cylinder 2 side for inspecting the welding quality fail, repair welding processes 119 and 122 are performed on the rejected welded part and its vicinity. I am trying to repair it.

  In these repair welding processes 109, 116, 119, 122, for example, one-pass cladding is performed using welding conditions in which the welding current, the amount of heat input, and the like are reduced as compared to the welding conditions when the fillet joint is fully welded. By repairing it, it is possible to easily repair the build-up.

  In addition, about the method to test | inspect welding quality, it mentions later in detail using another Example (FIGS. 31-35, FIGS. 44-46).

  First, in the wire welding cross-sectional area determination step 102 performed before welding, the throat thickness L of the inner welded portion 7 to be formed on the predetermined fillet joint portion 5 is equal to or greater than the plate thickness T1 of the heat transfer copper fin 3 (L ≧ T1). The wire welding cross-sectional area Aw is calculated and determined from the wire feed speed Wf or the wire feed speed Wf, the wire diameter d, and the predetermined welding speed V.

  Note that the throat thickness L of the inner welded portion 7 is the minimum distance from the molten bottom portion on the heat transfer copper fin 3 side to the weld bead surface, as shown in the wire welding cross-sectional area determining step 102 in FIG. 3 and FIG. 4. That is. Moreover, the inner side welding part 7 of the fillet joint part 5 illustrated in the place of the wire welding sectional area determination step 102 is formed by welding one end face part of the heat transfer copper fin 3 to the outer surface of the inner cylinder 1. Although assumed and drawn, it is also assumed that the other end surface portion of the heat transfer copper fin 3 is welded to the inner surface of the outer cylinder 2 to form the other outer welded portion 10, and the welding shown in FIG. Omitted because it is similar to the structure.

  Next, in the first welding step 103 on the inner cylinder 1 side, as shown in FIG. 5, each end surface portion on one side of a predetermined number (N) of heat transfer copper fins 3 on the outer surface of the steel inner cylinder 1. To form the wide-angle fillet joint portions 5-1, 5-2,..., 5-N at substantially equal intervals. In FIG. 5, only two heat transfer copper fins 3 are shown and the other portions are omitted, but a predetermined number of heat transfer copper fins 3 to be welded are in the circumferential direction of the outer surface of the inner cylinder 1. Inclined deployment at approximately equal intervals.

  In the first welding step 103 on the inner cylinder 1 side, the outer cylinder 2 is not deployed, and the heat transfer copper fins 3 are inclinedly disposed on the outer surface of the inner cylinder 1 to form a wide-angle fillet joint 5- By forming 1, 5-2... 5-N, the temporary assembly work of the heat transfer copper fin 3 before the main welding and the fillet joint portions 5-1, 5-2. A welding operation or the like can be easily performed.

  In the first welding step 103 on the inner cylinder 1 side, as shown in FIGS. 4 and 5, a predetermined number (N) of heat transfer copper fins 3 are attached to the outer surface of the inner cylinder 1 to fillet joints. After forming the portion 5 at N locations, welding at N locations on the inner cylinder 1 side that is repeatedly welded (continuous welding) one pass at a time to the N fillet joint portions 5-1, 5-2. , 5-2, 5-N are divided in advance into about 1 to 5 places, and the divided 1 to 5 fillet joint parts are divided. 5-1, 5-2, 5-3, 5-4, 5-5 are welded and the welded portion is repeatedly inspected. It is divided into a welding process 106 for repeated welding and inspection.

  In the repeated welding process 105 of N places on the inner cylinder 1 side, the welding start position from each welding start position of the N fillet joint portions 5-1, 5-2,. For each of the welding lines up to (dotted lines 6-1, 6-2... 6-N marked on the lower surface of the heat transfer copper fin 3), CuSi wires containing silicon are used, and the preceding TIG and subsequent MIG Welding is performed one pass at a time by composite welding or MIG welding.

  In the repeated welding step 105 of welding at the N locations on the inner cylinder 1 side, for example, the joint to be welded (both the inner cylinder 1 and the heat transfer copper fin 3) side is rotated and moved by a rotary drive device or the like. After changing the posture of the weld line 6-1 of the power fillet joint 5-1 in the vertical direction, the TIG-MIG welding torch or the MIG welding torch having an integral structure is positioned on the welding line 6-1 in a downward posture. The weld line in the case where both end portions of the heat transfer copper fin 3 are flat surfaces is a position where the wire position or torch position (including electrode position) is shifted from the end surface portion to the surface side of the heat transfer copper fin 3 by a predetermined distance. The shift amount S1 (first distance S1) is preferably set in the range of S1 = 0 to 4 mm. In addition, the TIG-MIG welding torch or the MIG welding torch having a monolithic structure in the downward posture is welded along the weld line 6-1 from the welding start position to the end position to perform one pass welding, and a weld bead and a weld cross section. The part 7-1 is preferably formed.

  Thus, by shifting the wire position or torch position to the heat transfer copper fin 3 side and welding, the heat melting of the heat transfer copper fin 3 is promoted and the penetration depth on the steel side is suppressed. The throat thickness L having a sufficient size and a heat conduction cross-sectional area effective for heat removal can be reliably ensured, and a shallow penetration weld bead and weld cross section can be obtained.

  When the one-pass welding of the welding line 6-1 is completed, the welding torch is moved around, and in the welding of the next welding line 6-2, the joint side is rotated again, and the corresponding welding line 6-2 is moved vertically. After changing the posture in the direction, the welding torch that has been moved to avoid is moved along the welding line 6-2 to perform positioning in a downward posture. One-pass welding may be performed while the welding torch travels along the welding line 6-2.

  In this way, the operation of changing the orientation of the weld line of the corresponding fillet joint portion 5, the operation of positioning the welding torch on the weld line, the operation of performing one-pass welding on the weld line while running the welding torch, 1 pass By performing a series of repetitive operations such as an operation for avoiding the welding torch after welding construction, each welding line 6-1, 6-2. As shown in FIG. 6, a weld bead and weld cross sections 7-1, 7-2... 7-N can be formed, respectively.

  Note that the composite welding of the preceding TIG and the succeeding MIG or MIG welding will be described later using another embodiment (FIGS. 19 to 30 and FIGS. 36 to 43).

  On the other hand, the welding operation is the same in the welding process 106 of the welding and inspection in the small number unit on the inner cylinder 1 side that repeats the inspection of the inner cylinder 1 side (1-5 locations) and the inspection of the welded portion. As described above, a single-pass welding is performed while the TIG-MIG welding torch or the MIG welding torch having the downward structure is moved along the welding line 6-1 from the welding start position to the end position. It is preferable to form the weld cross section 7-1. After welding, inspection of the welding quality is performed in the inspection process 117 on the inner cylinder 1 side, and when the inspection of the welding quality is unsuccessful, the repaired welding process 119 repairs the rejected welded part and its vicinity. I am trying to repair it.

  By using CuSi wire to perform composite welding of preceding TIG and subsequent MIG or MIG welding, copper, steel, and Si can be mixed together in a state where they can be dissolved even in the case of dissimilar material welding of copper and steel. As a result, it is possible to form a good weld bead and weld cross section (welded part) without cracks. Although it is possible to use pure copper Cu wire with high thermal conductivity, in the case of pure copper Cu wire, welding is performed for dissimilar material welding of copper and steel compared to CuSi wire containing silicon. This was not adopted in the welding method of the present example because of poor quality and weld quality and high crack sensitivity.

  In this embodiment, the weld bead of each fillet joint portion 5-1, 5-2,..., 5-N and the weld cross-section portions 7-1, 7-2,. In addition, at least the throat thickness L of the welded portion is formed to be equal to or greater than the plate thickness T1 of the heat transfer copper fin 3 (L ≧ T1), and the penetration depth c on the inner cylinder 1 side is 0.05 mm to 6 mm (0.0. 05 ≦ c ≦ 6 mm) (the penetration depth c will be described later).

As a result, it is possible to reliably secure a throat thickness L having a sufficient size and a heat conduction cross-sectional area effective for heat removal at the welded portion of each heat transfer copper fin 3 on the inner cylinder 1 side, and defects such as cracks. It is possible to obtain a weld bead and a welded cross-section with good quality. Moreover, it can contribute to improvement of heat removal performance and reduction of manufacturing cost. Furthermore, also about the tensile strength of a weld part, the intensity | strength of 100 N / mm < ² > or more can be obtained reliably.

  If the throat thickness L described above is too smaller than the plate thickness T1 of the heat transfer copper fin 3, for example, it is necessary to conduct heat from the inner cylinder 1 side to the heat transfer copper fin 3 side via the inner welded portion 7. As a result, the heat conduction cross-sectional area is reduced, which hinders improvement of heat removal performance. Therefore, the throat thickness L of the welded portion is formed to be equal to or greater than the plate thickness T1 of the heat transfer copper fin 3 (L ≧ T1). In addition, if the penetration depth c on the inner cylinder 1 side is too deep, the melting ratio (dilution ratio) of the steel with respect to the cross-sectional area of the welded portion increases, so that the thermal conductivity of the welded portion decreases and cracking susceptibility increases. It tends to be expensive. If the penetration depth c is too shallow, the tensile strength tends to decrease due to insufficient bonding with the steel side. Therefore, the penetration depth c on the inner cylinder 1 side is formed to be 0.05 mm or more and 6 mm or less (0.05 ≦ c ≦ 6 mm).

  In the inspection process 107 on the inner cylinder 1 side after the repeated welding on the inner cylinder 1 side is finished, whether or not weld beads are well formed in each welded portion of the inner cylinder 1, and defects such as cracks and undercuts are present. Inspection / confirmation of welding quality, such as whether or not there is a throat thickness L or penetration depth c, is performed. If it is acceptable in step 108, the process proceeds to the second welding process 110 on the outer cylinder 2 side, which is the next process. If there is an unacceptable weld location, the process proceeds to repair welding process 109, and is rejected in repair welding process 109. Repair welding is performed at and near the weld location. In addition, the inspection process 107 on the inner cylinder 1 side may be omitted, and the inspection process 107 on the inner cylinder 1 side may be performed after the welding operation of both the inner cylinder 1 and the outer cylinder 2 is completed.

  Next, in the second welding process 110 on the outer cylinder 2 side, the first welding process 103 on the inner cylinder 1 side, the repeated welding process 105 for welding N locations on the inner cylinder 1 side, and the minor unit on the inner cylinder 1 side. 7, after the end of the repeated welding process 106 and the inspection process 107 and 117 on the inner cylinder 1 side, as shown in FIG. 7, the outer periphery of the heat transfer copper fin 3 welded to the inner cylinder 1 side An integral cylindrical outer tube 2 is arranged on the side, and the other end face portions of the predetermined number (N) of heat transfer copper fins 3 are butted to each of the wide-angle fillet joint portions 8-1, 8. -2 ... 8-N are formed at substantially equal intervals.

  In FIG. 7, as in FIG. 5, only two heat transfer copper fins 3 are shown and other portions are omitted, but a predetermined number (N) of heat transfer copper fins 3 to be welded are The inner cylinder 1 and the outer cylinder 2 are inclined at substantially equal intervals, and the weld beads and weld cross sections 7-1, 7-2... 7-N on the inner cylinder 1 side have already been formed. It is shown by reversing the posture on the joint side.

  Further, in the second welding step 110 on the outer cylinder 2 side, as shown in FIGS. 3, 4, 7 and 8, after N fillet joint portions are formed on the outer cylinder 2 side, Of the fillet joints 8-1, 8-2,..., 8-N repeatedly welded (continuously welded) one pass at a time, N welding on the outer tube 2 side 112, and about 1 to 5 places Of the fillet joints 8-1, 8-2 to 8 -N of the outer cylinder 2 on the outer tube 2 side, which repeats both welding and inspection so as to inspect the welded portion after the welding. It is divided into a welding process 113 in a small number of units and a repeated welding process 113 for inspection.

  In the repeated welding step 112 for welding N places on the outer cylinder 2 side, as in the repeated welding process 105 for welding N places on the inner cylinder 1 side, N fillet joints 8 to be welded for each pass are provided. -1,8-2 ... 8-N welding lines from the welding start position to the end position (dotted lines 9-1, 9-2 ... 9- marked on the lower surface of the heat transfer copper fin 3) For N), a CuSi wire containing silicon is used, and welding is sequentially performed one pass at a time by composite welding of the preceding TIG and the subsequent MIG or MIG welding.

  As in the case of welding of the inner cylinder 1, even in the case of welding on the outer cylinder 2, the joint to be welded (the inner cylinder 1, the outer cylinder 2, and the heat transfer copper fin 3) is rotated and moved by a rotary drive device or the like. Then, after changing the posture of the weld line 9-1 of the fillet joint part 8-1 to be welded in the vertical direction, the TIG-MIG welding torch or the MIG welding torch of the integral structure is directed downward on the welding line 9-1. Position with posture.

  As described above, the welding line in the case where the both end surface portions of the heat transfer copper fin 3 are flat surfaces has a wire position or a torch position (including electrode position) from the end surface portion to the surface side of the heat transfer copper fin 3 by a predetermined distance. The shifted position S1 is preferably set in the range of S1 = 0 to 4 mm. The weld bead and the weld cross section are welded by one pass while the TIG-MIG welding torch or the MIG welding torch having the downward posture is moved along the welding line 9-1 from the welding start position to the end position. 10-1 may be formed.

  Thus, by shifting the wire position or torch position to the heat transfer copper fin 3 side and welding, the heat melting of the heat transfer copper fin 3 is promoted and the penetration depth on the steel side is suppressed. The throat thickness L having a sufficient size and a heat conduction cross-sectional area effective for heat removal can be reliably ensured, and a shallow penetration weld bead and weld cross section can be obtained.

  When the one-pass welding of the welding line 9-1 is completed, the welding torch is moved around to avoid the welding of the next welding line 9-2 and the welding of the subsequent welding line, as described above. Operation to change the position of the weld line of the fillet joint, operation to position the welding torch on the weld line, operation to perform 1-pass welding on the weld line while running the welding torch, avoid welding torch after 1-pass welding operation By performing a series of repetitive operations such as an operation, a weld bead and a welded cross-sectional portion 10 are respectively connected to the weld lines 9-1, 9-2,... 9-N of a predetermined number (N) of fillet joint portions. -1, 10-2... 10-N can be formed.

  On the other hand, in the case of the inner cylinder 1 side even in the repeated welding step 113 of welding and inspection on the outer cylinder 2 side which repeats the welding (1 to 5 places) on the outer cylinder 2 side and the inspection of the welded portion, Similarly, as described above, the one-pass welding is performed while the TIG-MIG welding torch or the MIG welding torch having the downward structure is moved along the welding line 9-1 from the welding start position to the end position. Then, it is preferable to form the weld bead and the weld cross section 10-1. The welding quality inspection process 120 on the outer cylinder 2 side is performed after welding, and if the welding quality inspection process 120 on the outer cylinder 2 side fails, the rejected welded part and its vicinity are repaired. Repair is performed in the welding step 122.

  Moreover, as shown in FIG.4, FIG7 and FIG.8, the weld bead of each fillet joint part 8-1, 8-2, ... 8-N welded, and its weld cross-section part 10-1, 10-2 to 10-N, at least the throat thickness L of the welded portion is formed to be equal to or greater than the plate thickness T1 of the heat transfer copper fin 3 (L ≧ T1), and the penetration depth on the outer cylinder 2 side c is 0.05 mm or more and 6 mm or less (0.05 ≦ c ≦ 6 mm).

As a result, as in the case of the inner cylinder 1 side described above, the welded portion of each heat transfer copper fin 3 on the outer cylinder 2 side has a sufficiently large throat thickness L and a heat conduction cross-sectional area effective for heat removal. Can be reliably ensured, and a weld bead having a good quality without defects such as cracks and a weld cross section thereof can be obtained. Moreover, it can contribute to improvement of heat removal performance and reduction of manufacturing cost. Furthermore, also about the tensile strength of a weld part, the intensity | strength of 100 N / mm < ² > or more can be obtained reliably.

  In the inspection step 114 on the outer cylinder 2 side after the repeated welding on the outer cylinder 2 side is completed, the weld beads are well formed in the respective welded portions on the outer cylinder 2 side, as in the welding inspection on the inner cylinder 1 side. Whether or not there are defects such as cracks and undercuts, and whether or not the throat thickness L, penetration depth c, etc. are satisfied is checked and confirmed. If it is acceptable (step 115), the process proceeds to step 125 to the next process, and if there is an unsuccessful weld location, the process proceeds to the repair welding step 116 to repair and weld the unsatisfactory weld location.

  As shown in FIGS. 3 to 8, in this embodiment, when the minimum distance from the molten bottom portion on the heat transfer copper fin 3 side to the weld bead surface is the throat thickness L of the welded portion, the throat thickness L is The wire welding cross-sectional area Aw is determined from the wire feed speed Wf or the wire feed speed Wf, the wire diameter d, and the predetermined welding speed V so as to be formed to have a predetermined size or more, and from the welding start position of each fillet joint portion. For each weld line to be welded to the end position, a CuSi wire containing silicon is used and welded one pass at a time by composite welding of the preceding TIG and subsequent MIG or MIG welding, and each welded fillet At the welded portion of the joint portion, at least the throat thickness L is formed to be equal to or greater than the plate thickness T1 of the heat transfer copper fin 3 (L ≧ T1), and the steel inner cylinder 1 side, the outer cylinder 2 side, or the inner Penetration depth on both sides of tube 1 and outer tube 2 There can also be formed 0.05mm or more than 6mm (0.05 ≦ c ≦ 6mm).

  In this embodiment, the wire welding cross-sectional area Aw is determined from the wire feed speed Wf or the wire feed speed Wf, the wire diameter d, and the predetermined welding speed V so that the throat thickness L is formed to a predetermined size or more. Then, after a predetermined number (N) of heat transfer copper fins 3 in the longitudinal direction of the outer surface of the inner cylinder 1 are abutted at substantially equal intervals to form N wide-angle inclined fillet joints, welding is performed. Sometimes using a CuSi wire containing silicon, one pass for each fillet joint 5-1, 5-2... 5-N on the inner cylinder 1 side by composite welding of the preceding TIG and the subsequent MIG or MIG welding After completion of welding on the inner cylinder 1 side or after completion of welding on the inner cylinder 1 side and after inspection of the weld beads and weld cross sections 7-1, 7-2,... 7-N, heat transfer copper fins 3 An integral cylindrical outer cylinder 2 is arranged on the outer peripheral side of the cylindrical outer cylinder 2 and the inner surface of the cylindrical outer cylinder 2 is After a predetermined number (N pieces) of heat transfer copper fins 3 in the hand direction are brought into contact with each other to form N wide-angle inclined fillet joints, CuSi wires are used for welding, and a preceding TIG and a subsequent MIG are used. Are welded to the fillet joints 8-1, 8-2,..., 8-N on the outer cylinder 2 side by one pass, and the inner cylinder 1 side and the outer cylinder 2 side are welded. Then, at the welded portion of each fillet joint portion, at least the throat thickness L is formed to be equal to or greater than the plate thickness T1 of the heat transfer copper fin 3 (L ≧ T1), and the steel inner cylinder 1 side or outer cylinder 2 is formed. The penetration depth c on the side or both sides of the inner cylinder 1 and the outer cylinder 2 can be formed to be 0.05 mm or more and 6 mm or less (0.05 ≦ c ≦ 6 mm).

  In this embodiment, the wire welding cross-sectional area Aw is determined from the wire feed speed Wf or the wire feed speed Wf, the wire diameter d, and the predetermined welding speed V so that the throat thickness L is formed to a predetermined size or more. Thereafter, N end portions of the heat transfer copper fins 3 of a predetermined number (N) in the longitudinal direction of the outer surface of the inner tube 1 are abutted at substantially equal intervals to form N wide-angle inclined fillet joints, and then In addition, by using a CuSi wire containing silicon at the time of welding, 1 is applied to each fillet joint portion 5-1, 5-2,..., 5-N on the inner cylinder 1 side by composite welding of the preceding TIG and the subsequent MIG or MIG welding. Welded by each pass, or butted one end face of the heat transfer copper fin 3 of a predetermined number (N) in the longitudinal direction of the outer surface of the inner cylinder 1 at substantially equal intervals to form N wide fillet fillet joints. Later, N fillet joints are divided into 1 to 5 units in advance, and Welding and inspection of fillet joints so that the welded parts are inspected at the 1 to 5 divided fillet joints 5-1, 5-2. After the end of welding on the inner cylinder 2 side or the end of welding on the inner cylinder 2 side and the end of inspection of the welded portion, an integral cylindrical outer cylinder 2 is disposed on the outer peripheral side of the heat transfer copper fin 3, The other end face portions of a predetermined number (N) of heat transfer copper fins are abutted in the longitudinal direction of the inner surface of the cylindrical outer tube 2 to form N wide fillet fillet joint portions, and then CuSi is welded. Using a wire and welding one pass to each fillet joint portion 8-1, 8-2... 8 -N on the outer cylinder 2 side by composite welding of the preceding TIG and the subsequent MIG or MIG welding, or A predetermined number (N) of heat transfer copper fins 3 are abutted against each other in the longitudinal direction of the inner surface of the cylindrical outer cylinder 2 so as to be inclined at a wide angle. After N fillet joints are formed, the N fillet joints are divided into 1 to 5 units in advance, and the divided 1 to 5 fillet joints 8-1 and 8- 2... 8 -N welding is performed and the fillet joint is repeatedly welded and inspected so that the welded portion is inspected. The welded portion of the joint is formed with at least a throat thickness L equal to or greater than the plate thickness T1 of the heat transfer copper fin 3 (L ≧ T1), and the steel inner cylinder 1 side, outer cylinder 2 side or inner cylinder 1 Further, the penetration depth c on both sides of the outer cylinder 2 can be formed to be 0.05 mm or more and 6 mm or less (0.05 ≦ c ≦ 6 mm).

As a result, the throat thickness L having a sufficient size and a heat conduction cross-sectional area effective for heat removal can be reliably secured even at the welded portions of the heat transfer copper fins 3 on the inner cylinder 1 side and the outer cylinder 2 side described above. In addition, it is possible to obtain a weld bead having a good quality free from defects such as cracks and a weld cross section thereof. Moreover, it can contribute to improvement of heat removal performance and reduction of manufacturing cost. Furthermore, also about the tensile strength of a weld part, the intensity | strength of 100 N / mm < ² > or more can be obtained reliably.

  FIG. 9 is a flowchart showing an embodiment of a welding procedure outline of still another metal cask heat transfer copper fin.

  The main difference from the flowchart shown in FIG. 4 is that the first welding process 103 on the inner cylinder 1 side is divided into a continuous welding process 105 for continuous welding at N locations and a small number unit for the dividing system. The second step is to divide whether to use the integral cylindrical outer cylinder 2 or to use a plurality of outer cylinder plates divided into plates, The third is that the second welding process 110 on the outer cylinder 2 side is divided into a continuous welding process 112 for welding N points in a continuous system and a welding process 113 for welding and inspection with a small number of units in a split system. .

  In addition, the wire welding cross-sectional area determination process 102 performed before welding, the inspection processes 107 and 117 on the inner cylinder 1 side performed after welding, the inspection processes 114 and 120 on the outer cylinder 2 side, the rejected welded portion and the vicinity thereof The repair welding processes 109 and 116 for repairing the part are substantially the same as the contents shown in FIG.

  As shown in FIG. 9, in the welding procedure (No. 3) 101 of the heat transfer copper fin 3, the first welding process 103 on the inner cylinder 1 side performed after the end of the wire welding cross-sectional area determination process 102 is the inner cylinder 1. The choice of whether the fillet joint 5 that connects the outer surface and the end face of the heat transfer copper fin 3 is formed and welded in a continuous manner or in a split manner (step 104). In this case, the process proceeds to the welding process 105 for repeated welding of N points in the continuous method, and otherwise, the process proceeds to the welding process 106 for welding and inspection in a small number of units.

  In the repeated welding step 105 of welding at N locations on the inner cylinder 1 side, as described with reference to FIGS. 5 and 6, one of the heat transfer copper fins 3 of a predetermined number (N) on the outer surface of the steel inner cylinder 1. Each end face part is abutted to form wide-angle fillet joint parts 5-1, 5-2,..., 5-N at substantially equal intervals. And each weld line (each lower surface of the heat transfer copper fin 3) from each welding start position to the end position of N fillet joint parts 5-1, 5-2,..., 5-N to be welded for each pass. The dotted lines 6-1, 6-2,..., 6-N) described in 1) are welded one by one in order by using a CuSi wire containing silicon and performing composite welding of the preceding TIG and subsequent MIG or MIG welding. Install.

  The weld beads and weld cross sections 7-1, 7-2,... 7-N of each fillet joint thus welded have at least a throat thickness L of the welded portion of the heat transfer copper fins 3. It is formed to have a plate thickness T1 or more (L ≧ T1), and a penetration depth c on the inner cylinder 1 side is formed to 0.05 mm or more and 6 mm or less (0.05 ≦ c ≦ 6 mm).

As a result, it is possible to reliably secure a throat thickness L having a sufficient size and a heat conduction cross-sectional area effective for heat removal at the welded portion of each heat transfer copper fin on the inner cylinder 1 side described above, and cracks, etc. It is possible to obtain a weld bead and a weld cross section having no defects and good quality. Moreover, it can contribute to improvement of heat removal performance and reduction of manufacturing cost. Furthermore, also about the tensile strength of a weld part, the intensity | strength of 100 N / mm < ² > or more can be obtained reliably.

  On the other hand, in the welding step 106 in which welding and inspection are repeated by dividing into a small number of units, a predetermined number (N) of heat transfer copper fins 3 are divided into about 1 to 5 pieces in advance, and the divided 1 to 5 pieces of heat transfer are transferred. One end face portion of the hot copper fin 3 is abutted against the outer surface of the inner cylinder 1 to form each fillet joint portion (1 to 5 places) and then welded. The formation, welding, and inspection are repeated.

  For example, as shown in FIGS. 10 and 11, after one end surface portion of one heat transfer copper fin 3 is abutted against the outer surface of the inner cylinder 1 to form one predetermined fillet joint portion 5-1, One-pass welding is performed from the welding start position to the end position of the fillet joint portion 5-1 by composite welding of the preceding TIG and the subsequent MIG or MIG welding using the contained CuSi wire. After the end of welding, quality inspection of the welded portion is performed.

  Moreover, as shown in FIG.12 and FIG.13, after forming the fillet joint parts 5-1 and 5-2 in two places by abutting the one end surface part of the heat transfer copper fin 3 on the outer surface of the inner cylinder 1 Using a CuSi wire containing silicon, welding is started on the weld lines 6-1 and 6-2 of the fillet joint portions 5-1 and 5-2 by composite welding of the preceding TIG and the subsequent MIG or MIG welding. Welding is performed one by one from the position to the end position. After the welding at these two places, quality inspection of each welded part is performed.

  Here, an integral TIG-MIG welding torch or MIG welding torch is positioned on the welding line 6-1 of the first fillet joint 5-1 (dotted line marked on the lower surface of the heat transfer copper fin 3). It is good to arrange | position and construct 1 pass welding in a downward attitude | position, and to form the 1st welding bead and the welding cross-section part (welding part) 7-1. When the first welding is completed, an integral TIG-MIG welding torch or MIG welding torch is positioned on the welding line 6-2 of the second fillet joint portion 5-2 to perform one-pass welding. It is good to construct and form the 2nd weld bead and weld cross-section part (weld part) 7-2.

  As described above, the weld line in the case where both end portions of the heat transfer copper fin 2 are flat surfaces is a position where the wire position or torch position is shifted from the end surface portion to the surface side of the heat transfer copper fin 3 by a predetermined distance. Yes, the shift amount S1 may be set during welding in the range of S1 = 0 to 4 mm.

  Thus, by shifting the wire position or torch position to the heat transfer copper fin side and welding, the heat melting of the heat transfer copper fin 3 is promoted and the penetration depth on the steel side is suppressed, A throat thickness L having a sufficient size and a heat conduction cross-sectional area effective for heat removal can be surely ensured, and a shallow penetration weld bead and weld cross section can be obtained.

  When this welding is completed, the quality inspection of the corresponding weld bead and the weld cross sections (welded portions) 7-1 and 7-2 is performed in the inspection step 117 on the inner cylinder 1 side. In the inspection process 117 on the inner cylinder 1 side, as described above, whether or not the weld bead is well formed in each welded part on the inner cylinder 1 side, whether there is a defect such as a crack or an undercut, Inspection / confirmation of welding quality, such as whether or not the throat thickness L and the penetration depth c are satisfied. If it is acceptable (step 118), the process returns to the repeated welding step 106 of the next fillet joint formation and welding and inspection in a small number of units, and if there is an unacceptable welded portion, it proceeds to the repair welding step 119, Repair welding is performed at and near the rejected welds.

  In this way, by dividing the predetermined number (N) of heat transfer copper fins 3 into about 1 to 5 in advance and repeating the formation of the fillet joint, welding and inspection, for example, two machines When the metal cask is manufactured substantially simultaneously, the work of attaching the heat transfer copper fins 3 to the inner cylinder 1 side to form the predetermined fillet joint portions 5-1, 5-2, and the fillet joint portion after the formation The work of welding to 5-1 and 5-2 and the work of inspecting the quality of the welded portion can be performed substantially simultaneously, and it becomes possible to shorten useless play time and improve work efficiency. .

  In addition, although the number of divisions of the heat transfer copper fins 3 is limited to about 1 to 5 here, the number of the heat transfer copper fins 3 is increased to about 1 to 10 to repeat the formation of the fillet joint, welding, and inspection. It is easy to do so, and the same effect can be obtained.

  The second welding step 110 on the outer tube 2 side, which is performed after the inspection steps 107 and 117 on the inner tube 1 side, is performed on each end surface portion of the heat transfer copper fins 3 of the predetermined number (N) and the outer tube 2. It is where it is selected (step 111) whether the fillet joints 8-1, 8-2,..., 8-N connected to the inner surface are formed and welded in a continuous manner or in a divided manner. When the continuous method is selected, the process proceeds to a repeated welding process 112 for welding at N locations. Otherwise, the process proceeds to a repeated welding process 113 for welding and inspection with a small number of units.

  In the repeated welding step 112 of welding at N locations, as described with reference to FIGS. 7 and 8, the cylindrical outer cylinder 2 integral with the outer peripheral side of the heat transfer copper fin 3 welded to the steel inner cylinder 1 side. And the other end face portions of the predetermined number (N) of heat transfer copper fins 3 are abutted to each other so that the wide-angle fillet joint portions 8-1, 8-2,. Each is formed at equal intervals. And each welding line from each welding start position to the end position of N fillet joints to be welded for each pass (dotted lines 9-1, 9-2,... Marked on the lower surface of the heat transfer copper fin 3) For 9-N), CuSi wire containing silicon is used, and welding is performed one by one in order by composite welding of preceding TIG and subsequent MIG or MIG welding.

  As described above, the operation of changing the posture of the weld line of the corresponding fillet joint, the operation of positioning the welding torch on the welding line, the operation of performing one-pass welding on the welding line while running the welding torch, and one-pass welding By performing a series of repetitive operations such as an operation for avoiding the welding torch after the construction, each of the weld lines 9-1, 9-2,. A predetermined weld bead and weld cross sections 10-1, 10-2,..., 10-N can be formed.

  The weld bead and the weld cross sections 10-1, 10-2,... 10-N of the fillet joints thus welded have at least a throat thickness L of the welded portion of the heat transfer copper fin 3 thickness T1. It is formed as described above (L ≧ T1), and the penetration depth c on the inner cylinder 1 side is formed from 0.05 mm to 6 mm (0.05 ≦ c ≦ 6 mm).

As a result, the throat thickness L having a sufficient size and a heat conduction cross-sectional area effective for heat removal can be reliably secured at the welded portion of each heat transfer copper fin 3 on the outer cylinder 2 side, and cracks, etc. It is possible to obtain a weld bead and a weld cross section having good quality without any defects. Moreover, it can contribute to improvement of heat removal performance and reduction of manufacturing cost. Furthermore, also about the tensile strength of a weld part, the intensity | strength of 100 N / mm < ² > or more can be obtained reliably.

  On the other hand, in the repeated welding step 113 of welding and inspection in a small number of units, as shown in FIGS. A wide-angle inclined fillet joint by using the outer cylindrical plate 2-2 and the other end surface of the corresponding heat transfer copper fin 3 in the longitudinal direction of the inner surface of the outer cylindrical plate 2-2. 8-1 and 8-2 are formed. Then, CuSi wire is used at the time of welding, welding is performed on the fillet joint portions 8-1 and 8-2 at the formation locations by composite welding of the preceding TIG and the subsequent MIG or MIG welding, and the welded portion after the welding is inspected. Thus, the fillet joint portion is formed, welded, and inspected alternately and repeatedly.

  14, 15, 16, and 17, welding is performed on the welding lines 9-1 and 9-2 of the fillet joint portions 8-1 and 8-2 formed at one or two places. Although illustrated so as to form a weld bead and weld cross sections 10-1 and 10-2, a corner to be welded to the inner surface side of the outer cylindrical plate 2-2 using a wide outer cylindrical plate 2-2. After forming the meat joint portions at several places (for example, 1 to 5 fillet joint portions 8-1 to 8-5), the fillet joint portion 8 is obtained by composite welding of the preceding TIG and the subsequent MIG or MIG welding. -1 to 8-5 may be welded.

  In addition, the other end face of the heat transfer copper fin 3 is abutted against one of the plate-like outer tube plates 2-2 that has been divided into a plurality of pieces (predetermined number) in advance, so that a wide-angle inclined fillet joint portion is 1-5. After forming in the place, while welding to the fillet joint parts 8-1, 8-2, 8-3, 8-4, 8-5 of the 1 to 5 places, and so as to inspect the welded part, It is also possible to repeat the formation, welding, and inspection of the fillet joint divided into one outer cylinder plate. In addition, while using the plate-shaped outer cylinder plate 2-2, by alternately repeating the formation of the fillet joint portion and the welding construction and quality inspection of the fillet joint portion, the useless play time can be shortened, It becomes possible to improve efficiency. In addition, it is good to repeat until the welding construction of the predetermined number of outer tube plates 2-2 and the quality inspection of the welded portion are completed.

  The weld bead and weld cross-section 10-1, 10-2... 10-N of each fillet joint thus welded have at least a throat thickness L of the welded portion of the heat transfer copper fin 3. It is formed to have a plate thickness T1 or more (L ≧ T1), and a penetration depth c on the outer cylinder 2 side is formed to be 0.05 mm or more and 6 mm or less (0.05 ≦ c ≦ 6 mm).

As a result, as in the case of the inner cylinder 1 side, the throat thickness L having a sufficient size and a heat conduction cross-sectional area effective for heat removal are ensured at the welded portions of the heat transfer copper fins 3 on the outer cylinder 2 side. In addition, it is possible to obtain a weld bead and a weld cross-section with good quality that can be ensured with no defects such as cracks. Moreover, it can contribute to improvement of heat removal performance and reduction of manufacturing cost. Furthermore, also about the tensile strength of a weld part, the intensity | strength of 100 N / mm < ² > or more can be obtained reliably.

  Next, in the welding finishing process 123 of the outer cylinder 2, since it is necessary to make each plate-shaped outer cylinder board 2-2 into the structure of the integral outer cylinder 2, a predetermined number of outer cylinder plates 2-2 divided in advance are used. Each of the connection portions of the both sides in the width direction is welded (for example, MAG welding, TIG welding, etc.) to finish the structure of a cylindrical or polygonal cylindrical integral outer cylinder 2. The function as the original outer cylinder 2 can be provided by finishing the structure of the integral outer cylinder 2.

  On the other hand, in the inspection step 114 on the outer tube 2 side of each welded portion after welding the fillet joint portions 8-1, 8-2,. As in the case of the quality inspection inspection process, whether the weld bead is well formed in each welded portion on the outer cylinder 2 side, whether there is a defect such as a crack or undercut, the throat thickness L or the like Inspection and confirmation of welding quality, such as whether or not the penetration depth c is satisfied. If the result is acceptable (step 115), the process reaches the end 124 and proceeds to another next step 125. If there is an unacceptable weld location in step 115, the process proceeds to the repair welding step 116, and repair welding is performed for the reject weld location and the vicinity.

  Further, as shown in FIGS. 4 to 17, in this embodiment, a wide angle is obtained by abutting one end face portion of a predetermined number (N) of heat transfer copper fins 3 at substantially equal intervals in the longitudinal direction of the outer surface of the inner cylinder 1 in advance. After forming the inclined fillet joints at N locations, a CuSi wire containing silicon is used during welding, and each fillet joint 5-1 on the inner cylinder 1 side by composite welding of the preceding TIG and the subsequent MIG or MIG welding, 5-2... 5-N are welded one pass at a time, or one end face portion of a predetermined number (N pieces) of heat transfer copper fins 3 is abutted at substantially equal intervals in the longitudinal direction of the outer surface of the inner cylinder 1 to wide angle. After forming the N-filled fillet joints at N locations, the N fillet-joint portions 5-1, 5-2,... Welding work to fillet joints 5-1, 5-2, 5-3, 5-4, 5-5 in units of 5 locations, and the welds The welding and inspection of the fillet joint divided into a small number of units is repeated, or a predetermined number (N pieces) of heat transfer copper fins are divided into units of 1 to 5 pieces in advance and divided. 1 to 5 fillet joint portions 5-1, 5-2, 5-3, 5-4, 5 by matching one end surface portion of the heat transfer copper fin 3 in units of 1 to 5 with the outer surface of the inner cylinder After forming the -5, welding is performed, and the formation of the fillet joint divided into a small number of units, welding, and inspection are repeated so that the welded portion is inspected. After completion of welding on one side and inspection of the welded portion, an integral cylindrical outer tube 2 is disposed on the outer peripheral side of the heat transfer copper fin 3 and a predetermined number (N) of the inner surface of the cylindrical outer tube 2 is arranged in the longitudinal direction. The other end face portions of the heat transfer copper fins 3 of the sheet) are butted together to form N fillet joint portions having a wide angle slope, Using a uSi wire, one pass is welded to each fillet joint portion 8-1, 8-2... 8 -N on the outer tube 2 side by composite welding of the leading TIG and the trailing MIG or MIG welding, or a cylinder The other end face portions of the predetermined number (N) of heat transfer copper fins 3 are abutted in the longitudinal direction of the inner surface of the outer shell 2 to form N wide fillet fillet joints. The fillet joint portions 8-1, 8-2,..., 8-N are preliminarily divided into units of 1 to 5 locations, and the divided 1 to 5 locations are welded to the unit fillet joint portions, and Repeated welding and inspection of fillet joint portions 8-1, 8-2, 8-3, 8-4, 8-5 divided into a small number of units so as to inspect the welded portion, or an integral cylindrical shape Instead of the outer cylinder 2, a plate-like outer cylinder plate 2-2 that is divided into a plurality of sheets (predetermined number) in advance is used, and the inner surface of the plate-like outer cylinder plate 2-2 is used. In the longitudinal direction, the other end face portion of the corresponding heat transfer copper fin 3 is abutted to form wide-angle inclined fillet joint portions at 1 to 5 positions, and then the 1 to 5 fillet joint portions 8-1. 8-2, 8-3, 8-4, and 8-5 were welded, and the fillet joint was formed, welded, and inspected so as to inspect the welded portion, and divided into a plurality of pieces in advance. When using the plate-shaped outer cylinder plate 2-2, after the process of repeating the formation of the fillet joint portion, welding, and inspection, the connection portions of the plurality of outer cylinder plates in the width direction on both sides are connected. Each is welded to finish a cylindrical or polygonal cylindrical integral outer cylinder structure. In welding on the inner cylinder 1 side and outer cylinder 2 side, at least a throat thickness L is transferred to the welded portion of each fillet joint. It is formed to have a copper fin plate thickness T1 or more (L ≧ T1), and the inner tube 1 side made of steel or the outer tube 2 side or both sides of the inner tube 1 and the outer tube 2 are melted. Only depth c may be formed to 0.05mm or more than 6mm (0.05 ≦ c ≦ 6mm).

Thus, as described above, the throat thickness L having a sufficient size and the heat conduction cross-sectional area effective for heat removal can be reliably ensured, and the weld bead and the weld cross-section with good quality free from defects such as cracks. Can be obtained. Moreover, it can contribute to improvement of heat removal performance and reduction of manufacturing cost. Furthermore, the tensile strength of the welded portion can be reliably obtained at 100 N / mm ² or more.

  FIG. 18 and FIG. 19 show an example of a schematic configuration and a torch arrangement of an integrally structured TIG-MIG welding torch according to the present embodiment.

  As shown in FIG. 18, in the TIG-MIG welding torch 11 having an integral structure, a non-consumable electrode 13 such as tungsten, a first shield gas 14 is directed toward the tip of the non-consumable electrode 13 and the welded portion. A TIG unit 12 having a first gas passage (not shown) that flows out, a consumable wire 18 such as a CuSi wire, a wire passage (not shown) through which the consumable wire 18 is inserted, and a tip portion of the consumable wire 18 And the MIG unit 17 provided with the 2nd gas channel etc. which flow out the 2nd shield gas 19 toward a welding part is arranged.

  The first and second shield gases 14 and 19 can change the type and composition of the gas, but here, a mixed gas of Ar gas and He gas is used as the shield gas. By using a mixed gas of Ar gas and He gas for welding copper and steel, compared to pure Ar gas, the potential gradient is high, weldability and wettability are excellent, and the quality is good. It becomes easy to obtain a weld. Although not shown, a water channel for cooling the TIG-MIG welding torch 11 with circulating water is also provided.

  The TIG-MIG welding torch 11 has a long arm 31 that can travel and move with respect to the weld line 6-1 of the fillet joint portion 5-1 between the steel inner cylinder 1 and the copper heat transfer copper fin 3. Attached to the distal end in a substantially downward position via a mounting jig (not shown), or attached to the distal end of the long arm 31 via a mounting jig and a biaxial drive table (not shown) that can move left and right and up and down. It is attached and arranged in the direction of the weld line 6-1.

  Further, an articulated movable welding robot is used instead of the long arm 31 that can be moved and moved, and the TIG-MIG welding torch 11 is arranged (attached) to the wrist of the welding robot, and the TIG-MIG welding torch is arranged. While moving 11, the composite welding of the preceding TIG and the subsequent MIG may be performed from the start position to the end position of the weld line of the fillet joint portion.

  Furthermore, the TIG unit 12 on the non-consumable electrode 13 side of the preceding TIG is inclined at a receding angle −α1 in the direction opposite to the welding progress direction, and the MIG unit 17 on the consumable wire 18 side of the subsequent MIG is welded. It is inclined and arranged with a forward angle + α2 in the direction. The receding angle -α1 on the preceding TIG side is preferably in the range of 0 to 45 degrees. It is more preferable to arrange it in the range of 15 to 30 degrees. The forward angle + α2 on the other subsequent MIG side is preferably in the range of 15 to 45 degrees. It is more preferable to arrange it in the range of 15 to 30 degrees.

  Further, the distance interval f1 between the electrodes from the position where the extension line of the tip of the non-consumable electrode 13 intersects the weld line 6-1 of the joint base material to the tip of the consumable wire 18 is in the range of 3 to 9 mm. Good. It is even better if it is preferably placed in the range of 4-7 mm. The electrode height f2 from the weld line 6-1 of the joint base material to the tip of the non-consumable electrode 13 is preferably in the range of 3 to 9 mm. It is even better if it is preferably placed in the range of 4-7 mm.

  In this way, by arranging the TIG-MIG welding torch 11 and running and welding on the welding line, it becomes possible to stably perform composite welding of the preceding TIG and the subsequent MIG.

  If the receding angle −α1 of the TIG unit 12 and the advancing angle + α2 of the MIG unit 17 are too smaller than 15 degrees, for example, the distance interval f1 between the non-consumable electrode 13 and the consumable wire 18 can be brought close to a predetermined range. In addition, the shape of one molten pool 24 formed by the TIG arc 22 and the MIG arc 23 tends to be elongated and unstable. On the other hand, if the receding angle −α1 and the advancing angle + α2 are too larger than the above-described angle range, the droplets of the consumable wire 18 melted by the MIG arc 23 are likely to be spattered and scattered in the direction of the preceding TIG. May adhere to the non-consumable electrode 13 on the preceding TIG side and damage the non-consumable electrode 13, and the gas shielding property is likely to deteriorate, which is not preferable. Therefore, the receding angle −α1 on the preceding TIG side is preferably in the range of 0 to 45 degrees, and the advancing angle + α2 on the subsequent MIG side is preferably in the range of 15 to 45 degrees.

  On the other hand, if the value of the distance interval f1 between the non-consumable electrode 13 and the consumable wire 18 is too smaller than 3 mm, for example, the TIG arc 22 and the MIG arc 23 are too close and spatter generated from the consumable wire 18 on the subsequent MIG side. May adhere to the non-consumable electrode 13 on the preceding TIG side and damage the non-consumable electrode 13, and the behavior of the TIG arc 22 and the MIG arc 23 is likely to be unstable. On the other hand, if the distance interval f1 between the non-consumable electrode 13 and the consumable wire 18 is too larger than 9 mm, the shape of one molten pool 24 formed by the TIG arc 22 and the MIG arc 23 tends to be elongated and unstable, and the desired distance A weld bead and a weld cross section may not be obtained. Accordingly, the distance interval f1 between the electrodes from the position where the extension line of the tip of the non-consumable electrode 13 intersects the weld line 6-1 of the joint base material to the tip of the consumable wire 18 is in the range of 3 to 9 mm. Good.

  Furthermore, if the electrode height f2 from the weld line 6-1 of the joint base material to the tip of the non-consumable electrode 13 is too smaller than 3 mm, for example, a decrease in arc voltage and a decrease in heat input associated with the shortening of the TIG arc 22 Insufficient melting may occur, and the tip of the non-consumable electrode 13 is close to the surface of the molten pool 24, so that it is easily affected by changes in behavior of the molten pool 24 and scattered spatter. On the other hand, if the electrode height f2 from the weld line 6-1 of the joint base material to the tip of the non-consumable electrode 13 is too larger than 9 mm, arc destabilization and increased heat input accompanying the extension of the TIG arc 22 The heat transfer copper fins 3 may be melted excessively, which may cause undercutting, and the gas shield property is likely to deteriorate, which is not preferable. Therefore, the electrode height f2 from the weld line 6-1 of the joint base material to the tip of the non-consumable electrode 13 is preferably in the range of 3 to 9 mm.

  As shown in FIG. 19, the TIG welding power source 15 is connected between the non-consumable electrode 13 in the TIG unit 12 and the inner cylinder 1 of the joint base material via the power supply cables 16-1 and 16-2. In addition, the TIG arc 22 is generated at the welding location with the polarity on the non-consumable electrode 13 side being the negative electrode (minus) and the polarity on the inner cylinder 1 side being the positive electrode (plus). The other MIG welding power source 20 (including the wire feeding device) is connected between the consumable wire 18 in the MIG unit 17 and the inner cylinder 1 of the joint base material via power supply cables 21-1 and 21-2. In addition, the MIG arc 23 is generated in the vicinity of the rear of the TIG arc 22 with the polarity on the consumable wire 18 side being positive (plus) and the polarity on the inner cylinder 1 side being negative (minus).

  The first welding current Ia flowing through the non-consumable electrode 13 on the preceding TIG side and the second welding current Ib flowing through the consumable wire 18 (CuSi wire) on the subsequent MIG side repel each other. Two matching TIG arcs 22 and MIG arcs 23 form one molten pool 24 and are welded while moving in the welding progress direction 25. The ratio (Ia / Ib) between the first welding current Ia and the second welding current Ib is preferably set in the range of about 0.8 to 1.2. Further, both the first and second welding currents Ia and Ib are preferably fed with direct current to form two arcs of direct current.

  Welding current Ia between direct currents in the range of the ratio of the first welding current Ia flowing through the non-consumable electrode 13 and the second welding current Ib flowing through the consumable wire 18 (Ia / Ib = 0.8 to 1.2). By outputting Ib, the TIG arc 22 and the MIG arc 23 that repel each other are maintained in a state of being substantially deflected downward, and one molten pool 24 can be stably formed. Further, the droplets from the tip of the consumable wire 18 do not scatter and easily transfer into the molten pool 24, and the weld bead and weld cross section 7- having a good weld bead and weld cross section can be obtained. 1 can be obtained.

  When the ratio (Ia / Ib) between the first welding current Ia flowing through the non-consumable electrode 13 and the second welding current Ib flowing through the consumable wire 18 is too small or too large, the TIGs repel each other. Since a large deviation occurs between the arc 22 and the MIG arc 23, the arc behavior on the side with a smaller current becomes unstable due to the influence of the arc force on the side with a larger current, which tends to cause poor welding.

  On the other hand, for example, when the polarity on the TIG side is reversed from the negative electrode (minus) to the positive electrode (plus), the non-consumable electrode 13 such as tungsten is consumed violently due to high temperature overheating during welding, so that the arc behavior is unstable. This tends to cause poor welding and makes it difficult to weld for a long time. In addition, since the TIG arc 22 and the MIG arc 23 are deflected in a mutually attracting direction, droplets of the MIG side consumable wire 18 are welded to the non-consumable electrode 13 on the TIG side, and electrode consumption occurs in a short time. There is also. If the polarity of the other MIG side is reversed from the positive electrode (plus) to the negative electrode (minus), unstable arc behavior and spatter are likely to cause poor welding, making it difficult to weld for a long time. .

  In FIG. 19, for ease of explanation, the TIG arc 22 and the MIG arc 23 and one molten pool 24 are shown on the weld line 6-1 near the center, but the TIG arc 22 and the MIG arc are actually shown. 23 is a welding start position on the weld line 6-1 of the fillet joint portion 5-1 to be welded.

  For example, the joint (inner cylinder 1 and heat transfer copper fin 3) side to be welded is rotated by a rotary drive device or the like, and the welding line 6-1 of the fillet joint portion 5-1 to be welded is oriented in the vertical direction. After the change, the monolithic TIG-MIG welding torch 11 is positioned on the welding line 6-1 in a downward posture. Thereafter, the TIG-MIG welding torch 11 is stopped at the welding start position on the welding line 6-1. While flowing a mixed gas of Ar gas and He gas from both the opening of the TIG unit 12 in the TIG-MIG welding torch 11 and the opening of the MIG unit 17 at and near the welding start position, A negative electrode (minus) TIG arc 22 is generated from the tip of the non-consumable electrode 13 and the first welding current arrives at the steady value Ia or is sent as a consumable wire 18 of the subsequent MIG immediately after a predetermined time. A positive electrode (plus) MIG arc 23 is generated in the vicinity of the rear of the TIG arc 22 from the CuSi wire to be fed, and the second welding current Ib is reached to a steady value to repel each other. The TIG-MIG welding torch immediately after the MIG arc 23 generates one molten pool 24 at the welding start position or after a predetermined time has elapsed. 11 is made to travel to the welding end position of the fillet joint 5-1 while moving one molten pool 24 in the weld line direction.

  By carrying out welding in this way, as described above, the welding joint 5-1 has a good weld bead and a weld cross-section 7-1 on the weld line 6-1 from the welding start position to the end position. A weld can be obtained.

  FIG. 20 shows an example of a schematic configuration and a torch arrangement of a MIG welding torch as Embodiment 2 of the present invention. The example shown in this figure is an example in the case of using the MIG welding torch 26 instead of the TIG-MIG welding torch 11 described above.

  As shown in the figure, when the MIG welding torch 26 is used, the MIG is connected between the CuSi wire of the consumable wire 18 and the inner cylinder 1 of the joint base material via the feeding cables 29-1 and 29-2. A welding power source 28 is connected. In addition, the MIG welding torch 26 is similar to the above-described TIG-MIG welding torch 11 in that the distal end portion of a long arm (not shown) that can travel and move with respect to the welding line 6-1 to be welded. It is attached to the wrist of an articulated movable welding robot (not shown) in a substantially downward position via an attachment jig (not shown), and is arranged in the direction of the welding line 6-1. Further, the MIG welding torch 26 in the present embodiment is disposed so as to be substantially perpendicular to the welding progress direction or at an advance angle + α3. The advance angle + α3 is preferably in the range of 0 to 30 degrees. It is more preferable to arrange it in the range of 0 to 15 degrees.

  Although the advance angle + α3 is omitted, it is a torch inclination angle corresponding to the inclination angle + α2 of the MIG unit 17 in the TIG-MIG welding torch 11 shown in FIG. 18 and FIG. When the MIG welding torch 26 shown is used, the advance angle + α3 is preferably in the range of 0 to 30 degrees. It is more preferable to arrange it in the range of 0 to 15 degrees. If welding is performed with the advancing angle + α3 larger than 30 degrees, the MIG arc 23 is inclined too far forward, so that the droplet of the consumable wire 18 melted by the MIG arc 23 is likely to scatter forward (occurrence of spatter frequently). In addition, the gas shield property is liable to be lowered, which is not preferable.

  When performing MIG welding, the MIG arc (not shown) of the wire positive electrode (plus) is made while the MIG shield gas 27 made of a mixed gas of Ar gas and He gas is allowed to flow out from the opening at the tip of the MIG welding torch 26. 1) is generated from the welding start position on the weld line 6-1 of the fillet joint portion 5, one melt pool 24 is formed by one arc, and the MIG welding torch 26 is moved in the welding progress direction. We are trying to weld in a downward posture.

  Welding of the wire positive electrode (plus) that supplies DC current with DC MIG arc is also possible, but if pulse MIG arc that repeats high peak current and low current alternately is used, spatter is generated more than DC MIG arc. There is little welding.

  The angle θ1 between one end surface portion of the heat transfer copper fin 3 on the inner tube 1 side to be welded and the fillet joint portion 5 or the other end surface portion of the heat transfer copper fin 3 on the outer tube 2 side and the fillet joint portion 8 is θ1. = 120 ° ± 15 ° (105 ≦ θ1 ≦ 135 °) wide angle inclination (configuration), and both of the heat transfer copper fins 3 formed on both surfaces of the inner cylinder 1 and the outer cylinder 2 The angle θ1 of the fillet joint portion 5 with the end face portion is also preferably arranged within the same range as the above value. Further, the inclination angle θ2 on the other inner cylinder 1 side or outer cylinder 2 side is arranged to be in a range of θ2 = 30 degrees ± 15 degrees (15 ≦ θ2 ≦ 45 degrees) with respect to the horizontal line.

  The joint member (the heat transfer copper fin 3 and the inner cylinder 1 or the heat transfer fin 3 and the outer cylinder 2) is inclined in such an angle range, so that the same applies to the MIG welding torch 26 (TIG-MIG welding torch 11). ) Can be arranged in a substantially vertical downward position, the operability of the welding torch and the like is improved, and preparatory work and welding work before welding can be improved.

  As described with reference to FIGS. 1 and 2, each space portion 4 divided between the inner cylinder 1 and the outer cylinder 2 and a plurality of (N) heat transfer copper fins 3 includes the spent fuel. A substance (resin) that shields radiation emitted from the aggregate in a normal line is filled in a resin filling step that is performed separately. For this reason, as shown in FIGS. 4 to 7 and FIG. 9, when the angle θ1 of the fillet joint portion 5 is larger than 135 degrees, radiation can be effectively shielded by the resin filling described above. Since the plate width of each heat transfer copper fin 3 to be welded between the outer surface of the inner cylinder 1 and the inner surface of the outer cylinder 2 needs to be made large in advance at the time of welding construction, the production cost of the heat transfer copper fin 3 is increased. At the same time, at the time of welding the heat transfer copper fins 3 adjacent to each other, a part of the welding torch comes into contact with the adjacent heat transfer copper fins 3 and it is highly possible that the welding work cannot be performed.

  On the other hand, if the angle θ1 of the fillet joint portion 5 is smaller than 105 degrees, the plate width of the heat transfer copper fins 3 can be reduced and welding can be easily performed, but the radiation emitted from the assembly of spent fuel. A part of the amount is expected to be transmitted between the resins (the heat transfer copper fins 3 and the gaps), and it is not preferable because the radiation shielding ability may be reduced due to the leakage of the radiation amount.

  Therefore, by arranging the angle θ1 of the fillet joint portion 5 at a wide-angle inclination in the range of 105 ≦ θ1 ≦ 135 degrees, it is possible to perform welding work and secure the radiation shielding ability.

  Further, the inclination angle θ2 on the inner cylinder 1 side or the outer cylinder 2 side is an angle for disposing the MIG welding torch 26 (the same applies to the TIG-MIG welding torch 11) in a substantially vertical downward posture. For example, when the angle θ1 of the fillet joint 5 is to be reduced, the other inner cylinder 1 side or the outer cylinder 2 side may be changed. When the inclination angle θ2 is changed in the increasing direction, and the angle θ1 of the fillet joint portion 5 is increased, it is preferable to change the inclination angle θ2 in the decreasing direction.

  The integrated TIG-MIG welding torch 11 and the MIG welding torch 26 dedicated to MIG welding shown in FIGS. 18, 19 and 20 are long and movable by a drive device 311 as shown in FIG. Attached to the tip of the arm 31 (or the wrist of a multi-joint movable welding robot) in a substantially downward position via a fixture, or attached to the tip of the long arm 31 and 2 It is mounted in a substantially downward posture via an axis drive table and is disposed in the weld line direction.

  Moreover, from the welding start position of the weld line of the fillet joint part to be welded for each pass to the copper plate of the heat transfer copper fin 3 and the steel material of the inner cylinder 1 or the outer cylinder 2 and the fillet joint part, to the end position, The traveling operation and welding operation of the integrally structured TIG-MIG welding torch 11 or MIG welding torch 26 are executed in accordance with the traveling command of the long arm 31 by the welding control device 201 and the output commands to the TIG welding power source 15 and the MIG welding power source 20. While performing the composite welding of the preceding TIG and the subsequent MIG or MIG welding, welding is performed from the start position to the end position of the weld line of the fillet joint.

  In this manner, by placing the MIG welding torch 26 or the TIG-MIG welding torch 11 downward on the weld line 6-1 of the fillet joint portion of the joint slope, welding is performed, thereby starting from the start position of the weld line. While being able to weld stably to an end position, it becomes possible to obtain a favorable weld bead and a weld cross section.

  21 and 22 show an example of the shape of both end surfaces of the heat transfer copper fin 3 and the joint arrangement and torch arrangement in the MIT welding or the combined welding of the preceding TIG and the subsequent MIG according to the present embodiment.

  The shape of both end surfaces of the heat transfer copper fin 3 (length direction shortening) shown in FIG. 21 is inclined within a range of 30 ° ± 15 ° with respect to the surface of the heat transfer copper fin 3 (end surface inclination angle: 15 ≦ β1). It is an inclined surface shape 38 that is ≦ 45 degrees, and is processed in advance into an inclined surface substantially parallel to the surface of the inner cylinder 1 (or the surface of the outer cylinder 2). This is an example in which the MIG welding torch 26 is arranged on the weld line of the fillet joint portion including the heat transfer copper fin 3 having the inclined surface shape 38.

  On the other hand, the shape of both end surface portions of the heat transfer copper fin 3 shown in FIG. 22 is a flat surface shape 39 of an end surface (corresponding to β1 = 0) having no inclined surface. This is an example in which the TIG-MIG welding torch 11 is disposed on the weld line of another fillet joint portion provided with the heat transfer copper fin 3 having the flat surface shape 39. In this example, the non-consumable electrode 13 on the preceding TIG side is mainly illustrated, and the consumable wire 18 on the subsequent MIG side is omitted. When both end surface portions of the heat transfer copper fin 3 have the flat surface shape 39, the processing cost can be reduced as compared with the case of the inclined surface shape 38.

  Note that the MIG welding torch 26 shown in FIG. 21 and the TIG-MIG welding torch 11 shown in FIG. 22 can be interchanged and arranged on the weld line of the fillet joint portion to be welded.

  On the other hand, with respect to the joint angle θ1 of the fillet joint 5 between the inner cylinder 1 side (or outer cylinder 2 side) and one end face of the heat transfer copper fin 3, both end faces of the heat transfer copper fin 3 are inclined surface shape 38. The same applies to the case of the flat surface shape 39.

  As described above, the joint angle θ1 of the fillet joint 5 between the inner cylinder 1 side (or the outer cylinder 2 side) and the one end surface portion of the heat transfer copper fin 3 is θ1 = 120 degrees ± 15 degrees (105 ≦ θ1 ≦ 135 degrees) is formed at a wide angle inclination. The inclination angle θ2 on the other inner cylinder 1 side (the same applies to the outer cylinder 2) is arranged in a range of θ2 = 30 degrees ± 15 degrees (15 ≦ θ2 ≦ 45 degrees) with respect to the horizontal line. In addition, since there is no gap G on the bottom surface of the fillet joint portion 5, the position of the MIG welding torch 26 (or TIG-MIG welding torch 11) is shifted to the heat transfer copper fin 3 side. Since the first distance S1 (or the second distance S2) may change, the gap G, the first distance S1, and the second distance S2 are shown in FIG.

  The first distance S1 is the tip of the consumable wire 18 (or the extension line of the non-consumable electrode 13 and the heat transfer copper fin) from the end surface corner b point of the heat transfer copper fin 3 to the position corresponding to the weld line 6. It is the length (distance) obtained by shifting the position of the intersecting point with the three surfaces. The other second distance S2 is the weld line at the upper part where the extension line of the surface of the heat transfer copper fin 3 crosses the surface of the inner cylinder 1 (or the surface of the outer cylinder 2) from the point a to the point b. This is the length (distance) obtained by shifting the consumable wire 18 (or the non-consumable electrode 13) to the position.

  Further, there is a correlation between the first distance S1 and the second distance S2, which is expressed by an equation of S2 = S1 + T1 / tan (180−θ1) −T1 × tanβ1 + G / sin (180−θ1). When the value of β1 is 30 ° ± 15 ° as described above, the heat transfer copper fin 3 has the inclined surface shape 38, and S2 when β1 = θ1−90 ° is S2 = S1 + G / sin (180− It can be simplified to the equation of θ1). When the value of β1 is 0 degree, the heat transfer copper fin 3 has a flat surface shape 39, and S2 at that time is S2 = S1 + T1 / tan (180−θ1) + G / sin (180−θ1). The formula can be simplified.

  The TIG-MIG welding torch 11 or the MIG welding torch 26 is set to a substantially downward posture on the weld line at the first distance S1 range position or the second distance S2 range position, and the preceding TIG and the subsequent MIG By welding from the start position to the end position of the fillet joint portion by composite welding or MIG welding, stable welding can be performed from the start position to the end position of the weld line, and a good weld bead and A weld cross section can be obtained.

  23 and 24 show a welding apparatus employed in the first embodiment as the third embodiment of the present invention, and shows an example in which a TIG-MIG welding torch and a guide roller are arranged at the distal end portion of the long arm. is there.

  As shown in the figure, the TIG-MIG welding torch 11 having an integral structure for performing composite welding of the preceding TIG and the succeeding MIG has a long length via mounting jigs 34 and 35 and a biaxial drive table 36 that can move left and right and up and down. It is disposed (attached) at the tip of the arm 31. The biaxial drive table 36 can be driven in the horizontal direction and the vertical direction with respect to the welding line direction, and the biaxial drive table 36 automatically moves the horizontal and vertical positions of the TIG-MIG welding torch 11. be able to.

  Further, the rotationally movable guide roller 32 is located at the right position ahead of the TIG-MIG welding torch 11, is disposed below the long arm 31, and is a heat transfer away from the welding line by a short distance. It is arranged so as to rotate in contact with both surfaces of the surface portion of the copper fin 3 and the surface portion on the inner tube 1 side (or the surface portion on the outer tube 2 side). By the contact rotational movement of the guide roller 32, the TIG-MIG welding torch 11 can be easily traveled and guided in the weld line direction of the fillet joint portion.

  Further, if the welding of the fillet joint portion is small, such as bending of the weld line and deformation due to welding, and accurate positioning in advance, the guide roller 32 can be used without using a measuring device such as a slit light cutting sensor. While the TIG-MIG welding torch 11 travels and guides in the direction of the weld line of the fillet joint by contact rotation, composite welding of the preceding TIG and the subsequent MIG is performed from the start position to the end position of the fillet joint. It is possible to obtain a good weld bead and weld cross section.

  In addition, in the Example shown in FIG.23 and FIG.24, although the example of arrangement | positioning of the TIG-MIG welding torch 11 of integral structure is described, it is also possible to replace with the MIG welding torch 26 and perform MIG welding. it can. Further, the TIG-MIG welding torch 11 is arranged at the tip of the long arm 31 via the mounting jigs 34 and 35 and the biaxial drive table 36, but without the biaxial drive table 36 being mounted, -The MIG welding torch 11 can also be arranged at the tip of the long arm 31. Further, it is described that the long arm 31 is moved in the right direction and the welding operation is performed while the TIG-MIG welding torch 11 is moved in the right direction, but the long arm 31 is opposite to the right direction. When moving in the left direction, the guide roller 32 is replaced at the leading position, the TIG-MIG welding torch 11 is replaced at the subsequent position, and rotated 180 degrees so as to become the preceding TIG-following MIG, thereby moving the left direction The welding operation can be normally performed while moving to.

  Moreover, in the Example shown in FIG.23 and FIG.24, although the TIG-MIG welding torch 11 is arrange | positioned at the elongate arm 31, the articulated movable welding robot is used instead of the elongate arm 31, The TIG-MIG welding torch 11 (or MIG welding torch 26) is placed (attached) on the wrist of the welding robot, and the combined welding (or MIG welding) of the preceding TIG and the succeeding MIG is performed while moving the torch. Welding may be performed from the start position to the end position of the weld line of the joint portion.

  Next, the welding test method and results actually conducted by the present inventors will be described.

  First, there is a high possibility that the first and second distances S1 and S2 for shifting the gap G, the torch position, or the wire position of the dissimilar fillet joint portion 5 of copper and steel will change, and therefore the influence on the welding quality. In order to confirm the welding condition tolerance, a welding test for changing the gap G and the first distance S2 was performed, and the welding quality and the like were evaluated. Further, the relationship between the wire feed speed Wf, the wire weld cross-sectional area Aw, and the throat thickness L was also investigated. Furthermore, in order to investigate the relationship between the penetration depth c on the steel side, the dilution rate (melting ratio), cracks, etc., a test was also conducted in which a CuSi wire was directly welded to the steel plate surface.

  In the MIG welding test, a fillet joint of a copper plate (C1020P) having a thickness of 5 mm and a carbon steel plate (SM400A) having a thickness of 16 mm is used. In the TIG-MIG combined welding test, a copper plate (C1020P) having a thickness of 5 mm is used. A fillet joint with a carbon steel plate (SM400A) having a thickness of 50 mm was used. The welding wire used was a 1.2 mm diameter CuSi wire (MG960), and the shielding gas used was a mixed gas of Ar gas and He gas (50 to 70%).

  FIG. 25 shows the relationship between the wire feed speed Wf, the wire weld cross-sectional area Aw, and the throat thickness L according to the present invention, and the logical throat thickness L0 when the cross-sectional area of the wire weld portion is assumed to be an isosceles triangle. (Calculated value without penetration), throat thickness L (measured value with penetration) of the MIG welded part and TIG-MIG composite welded part actually welded, and an example of a photograph of the weld cross section are also shown.

  In the MIG welding test, a pulse current waveform was used, the welding speed was suppressed (204 mm / min), and the wire feed speed Wf was changed from 6 to 9 m / min (welding current 165 to 260 A) for welding. In the TIG-MIG combined welding test, the welding speed is increased to 350 mm / min, and the wire feed speed Wf is increased and increased by 10 to 12 m / min (MIG current 300 to 360 A, TIG current 300 to 360 A). Welded. FIG. 25 shows the result of the worst case.

  As can be seen from the figure, the weld cross-section of the copper plate and the steel plate is a convex shape (curved shape) on the bead surface, as shown in the weld cross-section photograph in the figure, and also has a penetration on the copper plate side, The throat thickness L of the weld cross section indicated by □ and ■ in the figure is larger than the logical throat thickness L0 indicated by ▲ in the figure, and is larger than the thickness (T1 = 5 mm) of the copper plate corresponding to the heat transfer copper fin. Is formed. Furthermore, in the case of TIG-MIG composite welding, since it is heated and melted by TIG arc and MIG arc, compared with the case of MIG welding, the amount of heat input Q is larger and the melting on the copper side becomes deeper. Even if Aw (indicated by ◯ in the figure) is small, the throat thickness L can be formed larger than the thickness of the copper plate (T1 = 5 mm).

From such test results, if the welding is set to a range of wire welding sectional area Aw of about ^{30~55mm 2 (30 ≦ Aw ≦ 55mm} 2), throat thickness L is equal to 5mm or more and the plate thickness T1 (L ≧ T1 = 5 mm) was determined. Moreover, as a result of estimating the heat input Q (kJ / cm) from the welding current, voltage and welding speed, it was found that the range of about Q = 12 to 35 kJ / cm (12 ≦ Q ≦ 35 kJ / cm) is sufficient. That is, if the wire welding cross-sectional area Aw is too small (30 mm ² or less), it is liable to be insufficient due to insufficient heat input and insufficient melting, or insufficient throat thickness L. Moreover, when there are too many wire welding cross-sectional areas Aw (55 mm < ² > or more), dripping of a molten metal, an undercut, etc. will occur easily.

  FIG. 26 shows the relationship between the shift amount S2 of the torch position and the throat thickness L and bead width W of the welded portion in MIG welding of the end face flat joint and end face inclined joint of the copper plate. In addition, the x mark in the figure indicates welding that is broken from the boundary between the bottom of the molten metal (bottom of the weld metal) and the surface of the steel base material during the cutting of the weld cross section due to insufficient joining and insufficient strength with the steel side. It is data.

  FIG. 27 shows typical weld bead appearances and welds of end face flat face joints and end face inclined face joints when MIG welding is performed by changing the shift amount S2 (second distance S2) of the torch position (wire position). It is one Example which shows a partial cross section photograph.

  As shown in FIG. 26, the bead width W of the MIG welded portion tends to decrease as the shift amount S2 increases, but the throat thickness L increases to the same extent or slightly, both of which are copper plates. It is formed to be larger than the plate thickness (T1 = 5 mm). In the case of a flat end face joint, since there is an opening at the bottom of the joint (size corresponding to the gap: 2.9 mm), a part of the molten metal flows into the opening during welding. Compared to the case of the inclined surface joint, the throat thickness L is about 0.5 to 1 mm smaller, and the other bead width W is about 1 to 1.4 mm larger. Further, even when the end face inclined surface joint has a gap (G = 0 to 2 mm), the throat thickness L is formed larger than the thickness of the copper plate (T1 = 5 mm).

  The maximum penetration depth c on the steel side is not described in FIG. 26, but as shown in the weld cross-section photograph in FIG. 27, a weld cross-section having a shallow penetration depth c is not obtained in MIG welding. can get. For example, in the case of a flat end face joint, when the shift amount S2 (second distance S2) of the torch position is 0.9 mm ((2) in FIG. 27), it is about 0.37 mm and 4.9 mm ( In FIG. 27 (2)), it was about 0.12 mm. When the shift amount S2 was large 6.9 mm, it broke during cutting and could not be measured, but it was determined that the penetration depth c was almost 0 mm.

  On the other hand, the maximum penetration depth c in the case of the end face inclined surface joint is approximately 0.15 mm and 3 mm when the shift amount S2 is 0 mm ((3) in FIG. 27) ((4) in FIG. 27). Since it was about 0.10 mm and fractured during cutting when S2 was 5 mm, the penetration depth c was determined to be almost 0 mm, as in the case of the end face flat surface joint.

  From the above results, the appropriate range of shift amount S2 (second distance S2) that can be formed when the throat thickness L of the weld is equal to or greater than the thickness T1 of the copper plate (L ≧ T1 = 5 mm) is the case of the end face flat joint. The range is about S2 = 0.9 to 6 mm, and when converted to the distance S1 (first distance) from the corner portion of the copper end face, the range is S1≈−1.9 to 3.1 mm. In the case of the end face inclined face joint, the range is about S2 = 0 to 4 mm. When converted to the distance S1 (first distance) from the corner of the copper end face, even when the gap G is 0 to 2 mm, S1≈0 to 0. The range is 4 mm. The penetration depth c of these welds is about 0.05 to 0.37 mm, and the lower limit value of the penetration depth c that can be joined is 0.05 mm or more. Note that the test data that was broken (×) during cutting was excluded because of insufficient strength.

  FIG. 28 shows the relationship between the penetration depth when the CuSi wire is directly welded to the carbon steel surface and the dilution ratio on the steel side. Both the MIG single welding result and the TIG-MIG composite welding result are shown together. Yes.

  The dilution rate α (%) shown in the figure was calculated by the equation: α = b / (a + b) × 100, where b is the cross-sectional area of the steel side and a + b is the cross-sectional area of the entire weld. The melt cross-sectional area of each weld is drawn from the weld cross-section photograph magnified about 10 times, and the melt cross-sections a and b inside the contour are calculated by the area calculation software, and then the dilution rate α is set. Each was calculated.

  As a result, when the wire feed speed Wf is increased (the MIG current is also increased), the penetration depth c and the dilution rate α tend to increase, and the welding speed is higher. In the case of TIG-MIG composite welding, the wire feed speed Wf was increased to 12.2 m / min for welding, but no cracks occurred.

  On the other hand, in the case of MIG single welding, the penetration depth c and the dilution rate α are larger than in the case of TIG-MIG composite welding, the penetration depth c is about 7 mm or more, and the dilution rate α is about When it was 50% or more, cracks opened on the surface of the weld bead occurred. For this reason, in TIG-MIG combined welding, if the wire feed speed Wf is further increased, the penetration depth c and the dilution rate α are estimated to increase, which is considered to cause cracking.

  From these results, the cracking boundary is estimated to be difficult to crack in the region where the steel side dilution rate α is 50% or more and the penetration depth c is about 6 mm or more, and is smaller than these values.

  In the case of MIG welding, since the arc having a pulse waveform that repeats a high peak current and a low base current is generated in the downward direction and welding is performed, the penetration depth increases with increasing arc force and directivity. It is conceivable that c increases.

  On the other hand, in the case of TIG-MIG composite welding, the non-consumable electrode of the preceding TIG and the wire electrode of the subsequent MIG are inclined in the welding direction, and the TIG arc and the MIG arc are deflected in a repulsive direction. Since it is generated and welded in this state, it is considered that the arc force and directivity are suppressed and increase in penetration depth is suppressed as compared with the case of MIG welding.

  In addition, when MIG welding is performed on the carbon steel surface using Cu wire instead of CuSi wire, since the cracking sensitivity is increased, for example, the wire feed speed Wf is about 10 m / min or more on the surface of the weld bead. It has been confirmed that an open crack occurs. On the other hand, in dissimilar joint welding of copper and steel, the input heat energy is dispersed to wire melting and copper and steel melting, so that a deep weld penetration is formed without deep penetration. It is considered that cracks are unlikely to occur because it is easy.

  Also, by welding using CuSi wire containing silicon, even when dissimilar joint welding of copper and steel, copper, steel and Si are mixed properly in a state where they can be dissolved, and there is no crack Good weld beads and weld cross sections can be obtained. If the penetration depth c on the steel side is about 6 mm or less (c ≦ 6 mm), the problem of cracking can be solved. Therefore, the allowable range of the penetration depth c is preferably 0.05 ≦ c ≦ 6 mm.

  However, since it is expected that the thermal conductivity of the welded portion is reduced by increasing the dilution rate α, the upper limit value of the penetration depth c is limited to 4 mm or less (c ≦ 4 mm) from the viewpoint of suppressing this. It was to be.

  Table 1 shows the welding conditions when the TIG-MIG composite welding test was performed by changing the gap of the fillet joint between the copper plate of the end face flat surface and the carbon steel and the shift amount of the torch position.

  In this welding test, in order to confirm the influence on the welding quality and the welding condition tolerance, the gap G of the fillet joint is changed (G = 0 to 3 mm) and the torch position shift amount S2 (second distance) S2) was changed (S2 = 3 to 9 mm), and a welding test of the preceding TIG and the subsequent MIG was performed in a downward posture. This is a fillet joint of a copper plate (C1020P) with a thickness of 5 mm and a carbon steel plate (SM400A) with a thickness of 50 mm. The welding wire is a 1.2 mm diameter CuSi wire, the shielding gas is a mixed gas of Ar gas and He gas. Each was used (refer to FIGS. 18 to 22 for the joint and torch arrangement).

  Table 2 shows the shape, tensile test and evaluation results of the TIG-MIG composite weld when the welding test is performed under the welding conditions shown in Table 1.

  In Table 2, each value and average value of the throat thickness L, bead vertical height H, penetration depth c, etc. of each welded cross-section sampled from the first half side and the second half side of each weld specimen are shown. In addition, the tensile load and tensile strength of each tensile test piece (welded joint with a width of 40 mm) taken from the central part of the same weld test piece are described, and whether or not the quality standard is satisfied The determination results are shown respectively.

For example, the throat thickness L is less than 5 mm (No. 9 and No. 13), the penetration depth c exceeds 4 mm (0), and the undercut at the bead toe is 1 mm. Exceeding one (No. 12 No. 12), and having a tensile load Wt of less than 20 kN (100 N / mm ² ) (No. 3 breaks during cutting) are rejected. The test pieces with other numbers satisfy each standard value, and therefore pass. Although not shown in Tables 1 and 2, a welding test is also performed on a joint with a shift amount S2 = 1 mm and a gap G = 0 mm.

  FIG. 29 shows the quality evaluation result and appropriate condition region of the welded part when the TIG-MIG combined welding test is performed by changing the gap of the fillet joint and the shift amount of the torch position. In FIG. 29, the abscissa indicates the distance S1 from the corner portion of the copper end surface, and the ordinate indicates the gap G. In the drawing, the appropriate condition region and the inappropriate region are described from the pass / fail of the welding quality evaluation. As described above, the relationship between the distance S1 (first distance S1) from the corner portion of the copper end face and the shift amount S2 (second distance S2) of the torch position is S1 in the case of the end face flat joint. = S2- {T1 / tan (180- [theta] 1) + G / sin (180- [theta] 1)}.

  As shown in the figure, the proper condition area (○ mark) that satisfies the quality standards is the area where the throat is insufficient (left mark ◆), the strength is insufficient (right mark ■), and the undercut excessive area (▲ mark). It is in the center part except and. In the region where the gap G is 3 mm or more, since there is only one test data, it is unknown, but it is thought that there is a possibility of leading to poor welding such as sagging or insufficient throat thickness.

  In addition, there is data that satisfies the quality standard (◯ mark) even in the area of insufficient strength (marked on the right side) and excessively undercut (marked with ▲), but it was excluded from the appropriate condition area. Furthermore, there is data (S1 = -1.9, G = 0 mm) that satisfies the quality standards in the throat thickness deficient area (marked with ♦) on the left side, but was excluded from the proper condition area.

  Therefore, the tolerance for the gap G is about G = 0 to 2 mm or about G = 0 to 3 mm, and the tolerance for the distance S1 from the corner portion of the copper end surface is about S1 = −0.5 to 4 mm. It was judged that. Or it can also be limited to about S1 = 0-4 mm. Further, when replaced with the second distance S2, S2 is approximately 2.5 to 7 mm (or S2 is approximately 3 to 7 mm).

  By performing welding in an appropriate region within such tolerance, it is possible to obtain a good weld bead and weld cross section that satisfy the quality standards.

  FIG. 30 is an example of a typical weld cross-section photograph of a welded portion where TIG-MIG composite welding is performed. FIG. 30 (1) shows a case where the gap G = 0 mm and the shift amount S2 = 5 mm. Is the case where the gap G = 2 mm and the shift amount S2 = 5 mm.

  As can be seen from (1) of FIG. 30, when the gap G is 0 mm, the bead surface has a convex shape (curved shape) and tends to be a welded cross-section having a shape melted to the vicinity of the back side of the copper plate. On the other hand, as can be seen from (2) of FIG. 30, when the gap is about 1 mm or 2 mm, the penetration of the shape penetrating the copper back side due to the acceleration of the melting of the copper plate and the inflow of the molten metal into the gap. At the same time, the penetration depth on the steel side also increases, and the bead surface tends to be a flat weld cross section. In both cases, the weld cross section satisfies the quality standard.

  In addition, in the case of TIG-MIG composite welding, the welding current (TIG current / MIG current) is higher and the welding speed is higher than in the case of MIG single welding, and the fillet joint between copper and steel is used. Since it is heated and melted by two arcs, the penetration on the copper side tends to be a deep weld cross section. In addition, about the crack, it was not recognized from any welding test piece.

  FIG. 31 shows the relationship between the throat thickness and the bead vertical height of the welded portion, and the corresponding values are extracted from the test data shown in Table 2 and graphed.

  As can be seen from the figure, there is a correlation between the bead vertical height H and the throat thickness L. Although there is variation, the relationship between the bead vertical height H and the throat thickness L can be expressed by the approximate experimental formula (first experimental formula) shown in the following formula (1). However, the constant b1 is 1.

Throat thickness: L≈b1 × H (1)
The values (dimensions) such as the throat thickness L and the penetration depth c inside the weld must be inspected (destructive inspection) by cutting the welded member, but the value of the bead vertical height H is the bead of the welded member. It can be measured from the surface. For this reason, the bead vertical height H is measured from the bead surface without performing a destructive inspection, and the value of the measured bead vertical height H is substituted into the first empirical formula (1). By calculating, the value of the throat thickness L inside the weld can be easily estimated.

  Moreover, when the calculated value of the throat thickness L calculated from the first empirical formula (1) is equal to or greater than the plate thickness T1 of the copper plate (corresponding to the heat transfer copper fin 3) (L ≧ T1), it is acceptable. When the thickness is smaller than the plate thickness T1 (L <T1), it can be determined that the throat is insufficient or the heat transfer area is insufficient. In addition, as described above, when the measured value of the throat thickness L measured from the weld cross-section obtained by the welding test in advance is smaller than the plate thickness T1 of the copper plate (L <T1), the throat thickness is insufficient or transmitted. It can also be determined that the thermal area is insufficient.

  When repairing an unacceptable welded part due to insufficient throat thickness or the like and the vicinity thereof, for example, as shown in FIG. 32, an unacceptable welded part 50 and the upper part in the vicinity (bead surface part near the copper plate or bead stop). By repairing 1-pass overlay in the vicinity of the end portion and forming the overlay repair portion 30, the throat thickness L can be restored to a copper plate thickness T1 or more (L ≧ T1 = 5 mm). The lack of heat area can be resolved.

  For example, in repair welding to be built up in one pass, as shown in FIGS. 3, 4 and 9, the welding conditions in which the welding current, the heat input, etc. are reduced compared to the welding conditions when the fillet joint is fully welded. Is used in repair welding processes 109, 116, 119, and 122, so that it is possible to easily build up and repair the lack of throat thickness and heat transfer area as described above. .

  FIG. 33 shows the relationship between the weld bead vertical height and the penetration depth.

  As can be seen from the figure, a correlation is recognized between the bead vertical height H and the penetration depth c. Although there is variation, the relationship between the bead vertical height H and the penetration depth c can be expressed by a polynomial approximation empirical formula (second experimental formula) shown in the following formula (2). However, the constant b2 is -0.0067, b3 is 0.22, b4 is -2.62, and b5 is 10.3.

Penetration depth: c = b2 × H ³ + b3 × H ² + b4 × H + b5 (2)
As described above, the bead vertical height H is measured from the surface of the bead without performing a destructive inspection, and the value of the measured bead vertical height H is substituted into the second empirical formula (2). By calculating the penetration depth c, it is possible to easily estimate the penetration depth c inside the weld. Moreover, when the calculated value of the penetration depth c calculated from the second empirical formula (2) is less than 0.05 mm (c <0.05 mm), the welded portion on the steel side is insufficient in joining or insufficient in strength. If it is determined that there is a calculated value of the penetration depth c exceeding 4 mm (c> 4 mm), it can be determined that the penetration is excessive.

  FIG. 34 shows the relationship between the throat thickness of the weld and the penetration depth. Similar to the cases of FIGS. 31 and 33, each corresponding value is extracted from the test data shown in Table 2. It is a graph.

  As can be seen from the figure, there is a correlation between the throat thickness L and the penetration depth c. Although there is a variation, the relationship between the throat thickness L and the penetration depth c can be expressed by a polynomial approximation empirical formula (third empirical formula) shown in the following formula (3). However, the constant b6 is -0.000067, b7 is 0.24, b8 is -2.87, and b9 is 11.4.

Penetration depth: c = b6 × L ³ + b7 × L ² + b8 × L + b9 (3)
Depth of penetration by substituting the calculated value of the throat thickness L calculated from the first empirical formula (1) showing the relationship between the bead vertical height H and the throat thickness L into the third empirical formula (3). By calculating the value of c, the penetration depth c inside the weld can be easily estimated without performing a destructive inspection. Moreover, when the calculated value of the penetration depth c is in the range of 0.05 ≦ c ≦ 4 mm, it is determined to be acceptable, and the calculated value of the penetration depth c is less than 0.05 mm (c <0.05 mm). ), It is determined that the weld portion on the steel side is insufficiently bonded or insufficient in strength, and if the calculated value of the penetration depth c exceeds 4 mm (c> 4 mm), the penetration is excessive. It can be determined that there is.

  In addition, as described above, when the measured value of the penetration depth c measured from the weld cross section taken in advance by the welding test is less than 0.05 mm or exceeds 4 mm, the steel side welding is performed. It can also be determined that the portion is insufficiently bonded and insufficient in strength, or excessively penetrated.

  As described above, since the inspection test for the weld cross section is a destructive inspection for cutting the welded member, it is desirable to change the non-destructive inspection if possible.

  According to the present embodiment, the bead vertical height H is measured from the surface of the weld bead, and the measured value of the bead vertical height H is expressed by the first and second experimental expressions (1) and (2), respectively. By substituting and calculating the throat thickness L and penetration depth c, the throat thickness L and penetration depth c inside the weld can be easily estimated without performing a destructive inspection. Also, the penetration depth c can be calculated by substituting the calculated value of the throat thickness L calculated by the experimental formula (1) into the experimental formula (3).

FIG. 35 shows the relationship between the penetration depth and the tensile load of the welded joint. In the figure, the tensile load Wt is 20 kN (σ = 100 N / mm ² ) or more as acceptable. Note that the tensile strength σ of the welded portion was calculated from the maximum tensile load Wt and the cross-sectional area of the copper plate portion (plate thickness 5 mm × width 40 mm) because the weld cross-sectional area for each tensile test piece was changed and could not be specified. .

  Since the actual metal cask is a long member having a length of 4000 to 5000 mm, assuming that the weld line length per one heat transfer copper fin is a minimum of 4 m, the tensile load of the welded portion of one copper plate ( 20 × 4000/40 / 9.8), it is possible to lift heavy objects of 200 tons or more.

When the penetration depth c was approximately 0 mm, it was set to 0 because it was broken during cutting of specimen collection due to insufficient joining. When the penetration depth c is 0.05 mm or more, there is a variation, but it has a value of 20 kN (σ = 100 N / mm ² ) or more, and when the penetration depth c increases, the throat Since the thickness L decreases, the tensile load (maximum tensile load) Wt tends to decrease, but all satisfy the reference value of 20 kN (σ = 100 N / mm ² ) or more.

  From such a tensile test result, if the penetration depth c is 0.05 mm or more, the tensile load Wt and the tensile strength σ satisfying the reference value can be ensured.

  Since the tensile test described above is a destructive inspection for cutting a welded member, it is desirable to change the tensile test if possible.

  According to the present embodiment, as described above, the bead vertical height H is measured from the weld bead surface side, and the penetration depth c is calculated using the first to third empirical formulas (1) to (3). By calculating, it is possible to easily estimate whether or not the tensile load Wt or the tensile strength σ of the welded portion 7 satisfies (passes) the reference value without performing a destructive inspection. When the calculated value of the penetration depth c is 0.05 mm or more, it can be determined as acceptable, and when it is less than 0.05 mm, it can be determined that the strength is insufficient.

  The results of the welding test and the tensile test described above describe the test results assuming welding of a fillet joint between a copper plate having a heat transfer copper fin thickness of T1 of 5 mm and carbon steel of a thick plate. Even when the plate thickness T1 is smaller or larger than 5 mm, it is possible to weld the joint portion or inspect the welded portion based on the above-described concept.

  On the other hand, when welding a joint part of a long member, the torch position (wire position / electrode position) with respect to the weld line to be welded due to factors such as joint fitting and assembly errors, bending of the weld line, deformation due to welding, etc. Misalignment) is likely to occur, resulting in poor welding. For this reason, since it is necessary to correct | amend the position shift of a torch position during welding, the sensor which detects a position shift is needed. It is considered that the positional deviation of the torch position can be corrected and controlled based on the positional deviation detection information detected by the sensor, so that the positional deviation can be prevented and a good weld without defect can be obtained.

  FIG. 36 shows an example using a slit light cutting type sensor for detecting the position of the weld line of the fillet joint portion to be welded and its positional deviation as Example 4 of the present invention. FIGS. 37 and 38 show examples of alignment of the torch position (wire position) and alignment of the origin position coordinates on the sensor side and display examples on the image monitor performed in Example 4 before welding. . In the drawing, an example of the MIG welding torch 26 for performing MIG welding is described, but the same applies to the case of the TIG-MIG welding torch 11 for performing combined welding of the preceding TIG and the subsequent MIG, and is omitted. .

  As shown in FIG. 36, the slit light cutting type sensor 41 is a TIG-MIG welding torch (not shown) that is a front position of the MIG welding torch 26 that performs MIG welding or an integrated structure that performs combined welding of the preceding TIG and the subsequent MIG. And the upper position of the weld line 6 of the fillet joint portion 5. Although not shown, the slit light cutting sensor 41 includes a slit light irradiator that irradiates the slit light beam 42, a camera that captures an image, a water-cooled water channel, and the like.

  Then, the slit light beam 42 is irradiated from the slit light irradiator in the direction of cutting the weld line 6 of the fillet joint portion 5, and the linear line image 45-representing the shape of the fillet joint portion 5 by the irradiated slit light beam 42. 1 and 45-2 are taken by the camera inside the slit light cutting sensor 41 and taken into the image processing device 43, and line images 45-1 and 45-2 are displayed on the image monitor 44.

  The line images 45-1 and 45-2 displayed on the image monitor 44 are aa points connecting the surface line of the heat transfer copper fin 3 and the surface line of the steel side (corresponding to the inner cylinder 1 or the outer cylinder 2). It is a line image of -P point-b point-bb point. Point b is an end face corner of the heat transfer copper fin 3. The image processing device 43 has a built-in welding program for detecting misalignment between the weld line position and the torch position of the fillet joint portion 5 to be welded. As will be described later, in addition to the welding program, an inspection program is built in the image processing apparatus 43, so that it can be used for inspecting the weld bead surface after welding.

  The linear line images 45-1 and 45-2 representing the shape of the fillet joint portion 5 are appropriately subjected to image processing by the image processing device 43. For example, during welding, the position b of the corner of the end face of the heat transfer copper fin 3 is extracted (detected) at substantially constant time intervals or at substantially constant distances, and from the point b to the surface side of the heat transfer copper fin 3 The P point position shifted by the predetermined distance S1 is detected. The detected P point position is the position of the weld line 6 of the fillet joint portion 5 to be welded, and becomes the position coordinate Pn (Yn, Zn) of the MIG welding torch 26 performing the welding operation behind the sensor. Since the amount of positional deviation (ΔYn, ΔZn) in the left and right and up and down directions of the torch position, it is written in the image monitor 44. Since the slit light cutting type sensor 41 is disposed at the front position of the MIG welding torch 26, the detection operation by the slit light cutting type sensor 41 is always performed at the position of the welding line that precedes the welding operation by the rear welding torch. become.

  On the other hand, as shown in FIGS. 37 and 38, the MIG welding torch 26 is moved to the welding start position (X0) on the weld line before welding to align the torch position (wire position). A position P0 obtained by shifting the wire tip position to the surface side of the heat transfer copper fin 3 by a predetermined distance S1 is a welding start position (X0). After this alignment, the slit light cutting type sensor 41 is moved to the welding start position (X0) (the welding torch is moved to avoid it) and the detection operation is performed. At the same position P0 as the alignment of the MIG welding torch 26, the sensor The origin origin coordinate P0 (Y0 = 0, Z0 = 0) may be set to 0.

  After starting the welding operation at the welding start position (X0), detection data Pn (Yn, Zn) detected by the slit light cutting sensor 41 and the image processing device 43 at an arbitrary welding line position (Xn) during welding progress And the deviation (Yn−Y0, Zn−Z0) from the origin position coordinate P0 (Y0 = 0, Z0 = 0) in the origin position alignment set before welding, the horizontal position deviation ΔYn and the vertical position Each deviation ΔZn is calculated. Further, the value of the positional deviation (ΔYn, Zn) in the left and right and up and down directions can be converted into a value obtained by averaging (smoothing) a plurality of pieces of data detected and calculated successively before use. .

  36, FIG. 37, and FIG. 38, for the fillet joint portion 5 in which the end surface portion of the heat transfer copper fin 3 has a flat surface shape, the b point position of the end surface corner portion and the heat transfer copper fin 3 Although the example which detects the P point position shifted to the surface side is illustrated, even in the case of the fillet joint portion 5 in which the end surface portion of the heat transfer copper fin 3 has an inclined surface shape, it is the same as the case of the flat surface shape In addition, it is possible to detect the b point position of the end face corner and the P point position shifted to the surface side of the heat transfer copper fin 3.

  Since the MIG welding torch 26 or the TIG-MIG welding torch 11 performs a welding operation at a position behind the slit light cutting sensor 41, the detection position detected in advance by the slit light cutting sensor 41 and the image processing device 43. Torch position (wire position or electrode position) in a direction to eliminate the left and right and vertical position shifts (ΔYn, Zn) at or near the position where the subsequent MIG welding torch 26 or TIG-MIG welding torch 11 reached (Xn). Correction control is performed. It should be noted that the torch position can be corrected and controlled in such a direction as to eliminate either the left-right position shift ΔYn or the vertical position shift Zn.

  By correcting and controlling the torch position in this way, it is possible to eliminate misalignment (ΔYn, Zn) between the welding line position and the torch position in both the left and right directions, and good welding with no defective bead on the welding line. A bead can be obtained.

  FIG. 39 shows slit light for detecting the position of a weld line or the like when a temporary welded portion is intermittently formed at the fillet joint portion 5 of the heat transfer copper fin 3 and the inner cylinder 1 (or outer cylinder 2). An example using the cutting sensor 41 is shown.

  For example, when the fillet joint 5 is provisionally assembled by abutting the heat transfer copper fins 3 against the outer surface of the inner cylinder 1 or the inner surface of the outer cylinder 2, intermittent tack welding is performed on the fillet joint 5 in advance. May do. For this reason, it is the fillet joint part 5 in which the part with a plurality of tack welding parts 56-1, 56-2, ... 56-n and the part without it are mixed.

  (2) in FIG. 39 is line images 45-1 and 45-2 taken from the fillet joint portion without the temporary welded portion by the slit light cutting type sensor 41 and the image processing device 43. 39 (3) has a line image 46 of the curved portion corresponding to the surface of the temporary bead in addition to the line images 45-1 and 45-2 taken from the fillet joint portion 5 having the temporary welded portion, Both line images have greatly different shapes.

  In the line image taken from the fillet joint with the tack welded portions 56-1, 56-2, ... 56-n, there is no b point position corresponding to the end face corner of the heat transfer copper fin 3, Since there is a line image 46 of the a point position corresponding to the tack bead toe and the curved portion corresponding to the surface of the tack bead, the tack welded portions 56-1, 56-2, ... 56-n. It is good to make it recognize that it is a recognition or an abnormal part, and treat the detection data of this temporary attachment part as non-adoption, and to maintain the torch position as it is.

  The line image taken from the fillet joint portion 5 without the other tack welded portion has no point a corresponding to the tack bead toe and the curve of the tack bead surface, and the heat transfer copper fin 3 Since there is a b point position corresponding to the end face corner portion, the b point position of this end face corner portion is detected, and the P point is shifted from the b point position to the surface side of the heat transfer copper fin 3 by a predetermined distance S1. The position coordinates Pn (Yn, Zn) of the. Detected data obtained by calculating the positional deviation (ΔYn, ΔZn) from the deviation between the detected position coordinate Pn (Yn, Zn) of the P point and the origin position coordinate P0 (Y0 = 0, Z0 = 0) described above. Good.

  Thus, based on the detection data detected and adopted from the fillet joint portion 5 without the tack welded portion, at the point where the subsequent welding torch has reached the position Xn in the welding line direction detected in advance or in the vicinity thereof. Temporary welding is performed by correcting the torch position in a direction that eliminates the positional deviations (ΔYn, ΔZn) in the horizontal and vertical directions, or by correcting the torch position in a direction that eliminates the positional deviation ΔYn in the horizontal direction. An abnormal correction operation or malfunction due to the influence of the presence or absence of a part can be prevented, and a good weld bead can be formed.

  FIG. 40 shows an example in which a TIG-MIG welding torch and a slit light cutting type sensor are arranged at the distal end portion of the long arm as the fifth embodiment of the present invention.

  As shown in the figure, the TIG-MIG welding torch 11 having an integral structure for performing composite welding of the preceding TIG and the succeeding MIG has a long length via mounting jigs 34 and 35 and a biaxial drive table 36 that can move left and right and up and down. Arranged at the tip of the arm 31. The biaxial drive table 36 can be driven in the horizontal direction and the vertical direction with respect to the welding line direction, and the biaxial drive table 36 automatically moves the horizontal and vertical positions of the TIG-MIG welding torch 11. be able to.

  Further, as described above, the slit light cutting sensor 41 is disposed at the front side of the TIG-MIG welding torch 11 and below the long arm 31 that is the upper position of the welding line, and is to be welded. The position shift (ΔY, ΔZ) of the weld line of the meat joint portion is detected, and the torch position is corrected based on the position shift detection data.

  By correcting the torch position in this way, it is possible to eliminate the positional deviation between the weld line and the torch position, and to obtain a good weld bead and weld cross section.

  Further, the rotationally movable guide roller 32 is located at the right position preceding the TIG-MIG welding torch 11 and the slit light cutting sensor 41, and is provided below the long arm 31, and from the welding line. The heat transfer copper fin 3 and the surface portion on the inner tube 1 side (or the surface portion on the outer tube 2 side) separated from each other by a short distance are arranged to rotate in contact with each other. By the contact rotational movement of the guide roller 32, the TIG-MIG welding torch 11 and the slit light cutting sensor 41 can be easily traveled and guided in the weld line direction of the fillet joint portion.

  In addition, if the welding of the fillet joint portion is small, such as bending of the weld line and deformation due to welding, and prior positioning is also accurate, it is possible to use the slit light without using the detection data from the slit light cutting sensor 41. The cutting type sensor 41 can be eliminated, and the welding operation can be performed while only guiding and rotating the guide roller 32 in the welding line direction of the fillet joint, and a good weld bead and weld cross section can be obtained. It is also possible to obtain.

  On the other hand, if bending of the weld line or deformation due to welding is likely to occur, the slit light cutting type sensor 41 can be provided to detect the displacement (ΔY, ΔZ) of the weld line, and based on the detected data Thus, the welding operation can be performed while correcting the torch position, and a good weld bead and weld cross section can be obtained.

  Reference numeral 37 denotes a shielding plate that shields radiant heat and scattered matter, and includes a TIG-MIG welding torch 11 (or MIG welding torch 26) that performs welding in the welding line direction, and a slit light cutting type sensor that detects misalignment and the like. 41 and at the upper position in the direction substantially perpendicular to the weld line, it is disposed below the distal end of the long arm 31. By providing the shielding plate 37, it is possible to shield radiant heat generated during welding by the TIG-MIG welding torch 11 (or MIG welding torch 26), and scattered matter such as spatter and fume. In addition, it is possible to protect devices such as the slit light cutting sensor 41 and the like at the same time.

  In the embodiment shown in FIG. 40, the slit light cutting sensor 41 is provided (attached) to the distal end portion of the long arm 31 via the attachment jig 34, but it is a biaxial drive that can move left and right and up and down. It can also be arranged at the tip of the long arm 31 via the table 36 so as to detect the positional deviation. Moreover, although the example of arrangement | positioning of the TIG-MIG welding torch 11 of integral structure is described, even if it replaces | exchanges for the MIG welding torch which performs MIG welding, the same function can be exhibited. In addition, the TIG-MIG welding torch 11 is disposed at the distal end of the long arm 31 via the mounting jigs 34 and 35 and the biaxial drive table 36, but the biaxial drive table 36 is not disposed. The TIG-MIG welding torch 11 can be disposed (attached) to the distal end portion of the long arm 31 via the jig 35.

  In the embodiment shown in FIG. 40, the long arm 31 is moved to the right and the TIG-MIG welding torch 11 and the slit light cutting sensor 41 are moved to the right while the welding operation and the detection operation are performed. It is described to do. When the long arm 31 is moved in the left direction opposite to the right direction, the guide roller 32 is replaced at the head position, the slit light cutting sensor 41 is positioned at the intermediate position, and the TIG-MIG welding torch 11 is replaced at the subsequent position. At the same time, by rotating 180 degrees so as to be the preceding TIG-following MIG, the welding operation and the detecting operation can be normally performed while moving in the left direction. If the welding progress direction is reversed while maintaining the configuration shown in FIG. 40, it is reversed to the preceding MIG-following TIG, and the detection operation is in the rear position with respect to the welding operation. Since it becomes impossible to weld, it is not preferable.

  FIG. 41 is an example using a distance sensor that measures the distance to the member surface and a change in the distance, and FIG. 42 is an example in which a TIG-MIG welding torch and a distance sensor are provided at the distal end of the long arm. is there.

  That is, in this embodiment, a distance sensor 51 capable of measuring the distance and the distance change is used instead of the slit light cutting sensor 41 described above. This distance sensor 51 is an integral TIG-MIG welding torch 11 (or MIG welding torch 26) disposed in a substantially downward position at the distal end of a long arm 31 that can move and move in the weld line direction of the fillet joint. Or the front position of the inner cylinder 1 at a position behind the TIG-MIG welding torch 11 and at a position behind the rotationally movable guide roller 32 that is separated from the welding line by a short distance. Alternatively, one is disposed at each of an upper position in a direction substantially perpendicular to the surface on the outer cylinder 2 side, and an upper position in a direction substantially perpendicular to the surface on the heat transfer copper fin 3 side that is a short distance away from the welding line.

  Then, the distance measuring light 52 is irradiated from the tip of the distance sensor 51 to the surface on the inner cylinder 1 side or the surface on the outer cylinder 2 side and the surface on the heat transfer copper fin 3 side, and the reflected light is received to the surface. The distances Hs and Hc are measured, and the deviations ΔHs and ΔHc from the initially set reference distance are displayed on the distance measurement monitor 55 via the distance sensor controller 54.

  In addition, the distance measurement monitor 55 also indicates values obtained by distributing the distance deviations ΔHs and ΔHc into a position deviation component (ΔYs + ΔYc) in the horizontal direction and a position deviation component (ΔZs + ΔZc) in the vertical direction of the weld line. Based on this measurement data, the position deviation between the weld line and the torch position is corrected by correcting the torch position in a direction that eliminates the position deviation component (ΔYs + ΔYc) in the horizontal direction and the position deviation component (ΔZs + ΔZc) in the vertical direction. Thus, a good weld bead and weld cross section can be obtained.

  In the embodiment shown in FIGS. 41 and 42, two distance sensors 51 are provided one at the upper position on the inner cylinder 1 side and the upper position on the heat transfer copper fin 3 side. 1 is arranged at the upper position on the heat transfer copper fin 3 side, and the distance change (Hc, ΔHc) on the heat transfer copper fin 3 side of a thin plate that is much easier to deform than the thickness of the inner cylinder 1 is measured. Anyway. Since the inner cylinder 1 has a large plate thickness, the amount of deformation on the inner cylinder 1 side that accompanies welding is small and can be ignored. One distance sensor 51 provided at the upper position on the heat transfer copper fin 3 side. Thus, it is possible to measure the distance change accompanying the deformation or bending on the heat transfer copper fin 3 side and correct the torch position so as to eliminate the positional deviation between the weld line and the torch position based on this measurement data. .

  The distance sensor 51 is provided with a mounting jig 34 at the tip of the long arm 31 as in the case of the slit light cutting type sensor 41, but via a biaxial drive table 36 that can move left and right and up and down. It may be arranged at the distal end of the long arm 31 to measure the distance to the member surface and the change in the distance.

  Further, in the embodiment shown in FIGS. 41 and 42, the distance measurement light 52 is irradiated from the tip of the distance sensor 51 to the surface of the inner cylinder 1 and the heat transfer copper fin 3, and the reflected light is received to reach the surface. A non-contact type distance sensor 51 having a structure for measuring the distances Hs and Hc is used, but the distance is measured by bringing a measuring needle 49 movable in the vertical direction into contact with the surface of the inner cylinder 1 and the heat transfer copper fin 3. It is also possible to replace the contact type distance sensor having the structure described above.

  As described above, during the execution of the traveling operation and the welding operation of the TIG-MIG welding torch 11 or the MIG welding torch 26, based on the measurement data such as the distance change measured by the distance sensor 51, the welding line direction measured in advance is measured. By correcting the torch position in a direction that eliminates the lateral and vertical displacement caused by bending or deformation of the fillet joint at the point where the subsequent welding torch reaches or near the position Xn. The positional deviation between the weld line and the torch position can be eliminated, and a good weld bead and weld cross section can be obtained.

  In addition, as described above, the guide roller 32 disposed so as to rotate in contact with both the surface portion of the heat transfer copper fin 3 and the surface portion on the inner cylinder 1 side (or the surface portion on the outer cylinder 2 side). By the contact rotation, the TIG-MIG welding torch 11 or the MIG welding torch 26 and the distance sensor 51 can be easily traveled and guided in the welding line direction.

  Further, if the welding of the joint of the fillet joint is small, such as bending of the weld line and deformation due to welding, and accurate positioning in advance, the measurement data from the distance sensor 51 is not used or the distance sensor 51 is eliminated. Thus, it is possible to perform a welding operation while traveling and guiding in the direction of the weld line of the fillet joint portion only by the contact rotational movement of the guide roller 32, and it is possible to obtain a good weld bead and weld cross section. .

  Further, the shielding plate 37 disposed between the TIG-MIG welding torch 11 or the MIG welding torch 26 and the distance sensor 51 prevents radiant heat and scattered matter generated during welding by the TIG-MIG welding torch 11 or the MIG welding torch 26. Can be shielded. Further, it is possible to protect the devices such as the distance sensor 51 at the same time.

  40 and 41, the TIG-MIG welding torch 11 (or MIG welding torch 26) for performing welding, the slit light cutting sensor 41 or the distance sensor 51 for detecting or measuring positional deviation, and the like. However, instead of the long arm 31, an articulated movable welding robot is used, and the TIG-MIG welding torch 11 is attached to the wrist of the welding robot. Alternatively, a MIG welding torch 26, a sensor, or the like can be provided to perform a welding operation, a detection operation, or the like.

  For example, as shown in FIGS. 5 and 6, the weld lines 6-1, 6-6 of fillet joint portions 5-1 and 5-2 between the outer surface of the inner cylinder 1 and one end surface portion of the heat transfer copper fin 3. In the welding construction for No. 2, since the outer cylinder 2 is not present, the space for the fillet joints 5-1 and 5-2 is wide, so that it is possible to perform welding operation and detection operation using a welding robot. It is thought that.

  On the other hand, as shown in FIG.7 and FIG.8, after completion | finish of the fillet joint part 5-1 and 5-2 by the side of the inner cylinder 1 (welding part 6-1 and 6-2 formation), a heat-transfer copper fin In the welding construction to the weld lines 9-1 and 9-2 of the fillet joint portions 8-1 and 8-2 between the inner surface of the outer cylinder 2 arranged in the outer peripheral longitudinal direction of 3 and the other end surface portion of the heat transfer copper fin 3 Since the space space becomes narrow, it becomes difficult to insert the wrist of the welding robot. Therefore, it is necessary to change to the long arm 31 that can be inserted and traveled in a narrow space space to perform the welding operation. Conceivable.

  FIG. 43 shows the relationship between the shift amount of the torch position, the TIG current / voltage, and the MIG current / voltage in the composite welding of the preceding TIG and the subsequent MIG.

  As can be seen from the figure, for example, when the shift amount S2 (second distance S2) of the torch position is increased, the TIG current It has a small increase / decrease change, but the TIG voltage Et tends to increase. The other MIG current Im tends to decrease, but the MIG voltage Em has a small increase / decrease change.

  From these results, it is recognized that there is a correlation between the shift amount S2 of the torch position and the TIG voltage Et. For this reason, it is possible to perform control for automatically correcting the vertical torch position Z (electrode height) using the TIG voltage Et.

  For example, instead of the vertical position shift ΔZn of the detection data detected by the slit light cutting sensor 41 described above or the vertical position shift (ΔZs + ΔZc) of the measurement data measured by the distance sensor 51, the preceding TIG side The value of the TIG arc voltage signal (averaged TIG voltage signal) is used.

  In addition, the first reference voltage value V1 that is set by measuring in advance the arc voltage required to maintain the desired TIG arc length and the TIG arc voltage signal on the preceding TIG side during the welding process are detected in real time by the voltage detection means. Then, a voltage deviation (ΔV1 = Vn−V1) with respect to the value Vn of the TIG arc voltage detection signal subjected to the averaging process (smoothing process) is detected, and the position of the TIG-MIG welding torch 11 is moved up and down so as to eliminate the deviation voltage ΔV1. Perform correction control to correct in the direction.

  By performing voltage detection and position correction control in this way, it is possible to eliminate positional deviation in the vertical direction of the torch due to arc length change.

  In addition, one molten pool 24 is formed by the TIG arc 22 on the preceding TIG side generated at the welding start position P0 and the MIG arc 23 on the subsequent MIG side generated in the vicinity of the rear of the TIG arc. Immediately after moving one molten pool 24 in the welding line direction or after a predetermined time has elapsed, the TIG arc voltage signal on the preceding TIG side is detected only for a predetermined time (for example, about 1 to 3 seconds), and the average value obtained by averaging is calculated. The value Vn of the TIG arc voltage detection signal which is set to the second reference voltage value V2 and is detected and averaged (smoothed) in real time by the voltage detection means for the TIG arc voltage signal on the preceding TIG side during welding. The deviation voltage (ΔV2 = Vn−V2) from the second reference voltage value V2 is detected, and the position of the TIG-MIG welding torch 11 is adjusted so as to eliminate the deviation voltage ΔV2. Correction control for correcting in the vertical direction can also be performed.

  By performing voltage detection and position correction control in this way, it is possible to immediately respond to a setting change of torch alignment before welding and to form one molten pool by generating two arcs at the welding start position. It is possible to avoid voltage detection of an unstable arc that is likely to occur in the process, and it is possible to eliminate a positional shift in the vertical direction of the torch accompanying a change in arc length.

  FIG. 44 is an example showing detection of the weld bead and the bead vertical height H of the weld cross section 7 by the slit light cutting sensor 41 as the sixth embodiment of the present invention.

  For example, as shown in FIGS. 4 and 9, the slit light cutting type is performed in the inspection process 107 on the inner cylinder 1 side and the inspection process 114 on the outer cylinder 2 side for inspecting and confirming the quality of the weld bead and the weld cross section 7. A sensor 41 may be used. Further, every time the welding is completed on the fillet joint (welded part) on one end face of the heat transfer copper fin 3 of about 1 to 5 sheets, the weld bead after welding and the weld cross section 7 are slit light. As inspected by the cutting sensor 41, both the welding and inspection operations can be repeated.

  The means for automatically measuring the bead vertical height H from the bead surface portion of the weld bead and its weld cross section 7 is, for example, a slit light cutting sensor 41 for detecting the position of the weld line and its displacement as shown in FIG. This is a slit light cutting type sensor having a similar configuration. The slit light cutting type sensor incorporates a slit light irradiator for irradiating slit light, a camera for taking an image, a water channel for water cooling, and the like. The slit light cutting type sensor 41 is arranged at the upper position of the bead surface of the weld bead and its weld cross section 7, and the slit light beam 42 is emitted from the slit light irradiator in the direction of cutting the weld bead and its weld cross section 7. Irradiate. The linear line images 45-1 and 45-2 representing the shape of the welded part and the vicinity thereof by the irradiated slit light beam 42 are photographed by the camera inside the slit light cutting sensor 41 and taken into the image processing device 43. The images 45-1 and 45-2 are displayed on the image monitor 44. In addition, in FIG. 44, although the weld bead and the inner cylinder 1 side of the welding cross-section part 7 are shown horizontally, it can also test | inspect with the attitude | position similar to the attitude | position at the time of welding.

  The above-described image processing apparatus 43 has a built-in inspection program for detecting and measuring the weld bead, the bead toe portion of the weld cross section 7, the bead vertical height, the depth of the undercut, and the like after the end of welding. Has been. Further, as described above, a welding program for detecting a positional deviation between the position of the weld line to be welded and the torch position can be incorporated. By incorporating both the welding program and the inspection program in the image processing device 43, the slit light cutting sensor 41 can be used as a welding and inspection combined sensor having both functions for welding and inspection. You can also. Moreover, it can also be used as an inspection dedicated sensor different from the welding dedicated sensor.

  Further, the slit light cutting type sensor 41 is attached to, for example, a distal end portion of a long arm 31 that can be moved and moved on a welding line via an attachment jig, or is attached to the distal end portion of the long arm 31 and can be moved left and right and up and down. It may be attached via a possible two-axis drive table 36. When the slit light cutting sensor 41 is used as a welding / inspection sensor having both functions for welding and inspection, as described above, the front of the MIG welding torch 26 for performing MIG welding, or It is good to attach to the front of the TIG-MIG welding torch 11 having an integral structure for performing composite welding of the preceding TIG and the succeeding MIG. Then, after the end of welding, the inspection operation is performed by switching to the operation of inspecting the surface of the weld bead while maintaining the posture arranged at the upper position of the weld line 6. Further, it is only necessary to switch from the welding program to the detection program.

  After the end of welding, the slit light cutting sensor 41 and the image processing device 43 can perform detection operations by moving backward on the welding line from the welding end direction to the welding start side direction. Alternatively, after finishing the welding, the slit light cutting type sensor 41 is returned to the welding start side, and then, the slit light cutting is performed by moving on the welding line from the welding bead surface position on the welding start side to the surface position of the welding bead on the welding end side. It is also possible to cause the type sensor 41 and the image processing device 43 to perform a detection operation. A linear line image representing the shape of the surface portion of the weld bead and the vicinity thereof is taken into the image processing device 43 from the slit light cutting sensor 41 at substantially constant time intervals or at substantially constant distances, and image processing is appropriately performed. Yes.

  For example, an extended straight line (bb point-b point-c point) obtained by extending the straight line portion of the surface portion of the inner cylinder 1 in the direction of the bead toe end portion (b point) is drawn. The intersection position of the other bead toe that intersects with the straight line portion of the surface portion of the other heat transfer copper fin 3 is determined as a point, and with respect to the extended straight line (bb point−b point−c point), A position where a straight line (a point-d point-e point) drawn in a direction perpendicular to the point a and an extended straight line intersect at a right angle is determined as a point d. Then, the distance between the points a and d (a point-d point) is measured, and the measured distance (a point-d point) is determined as the value of the bead vertical height H, whereby the bead vertical height is determined. H can be measured. Also, the value of the measured bead vertical height H is substituted into the first and second empirical formulas (1) and (2), respectively, to calculate the value of the throat thickness L and the penetration depth c. By doing so, the throat thickness L and the penetration depth c inside the weld can be easily estimated without performing a destructive inspection.

  Thus, by automatically measuring the bead vertical height H from the bead surface using the slit light cutting sensor 41 and the image processing device 43, the weld quality can be inspected and the inspection time can be shortened. It becomes possible to do. Further, as described above, when the calculated value of the throat thickness L calculated from the formula (1) of the first empirical formula is equal to or greater than the plate thickness T1 of the heat transfer copper fin 3 (L ≧ T1), it is acceptable. If it is determined that there is less than the plate thickness T1 (L <T1), it can be determined that the throat is insufficient or the heat transfer area is insufficient. On the other hand, when the calculated value of the penetration depth c calculated from the expression (2) of the other second empirical formula is in the range of 0.05 ≦ c ≦ 4 mm, it is determined that it is acceptable.

  Further, when the calculated value of the penetration depth c is less than 0.05 mm (c <0.05 mm), it is determined that the weld portion on the steel side is insufficiently bonded or insufficient in strength, and further, the penetration depth is determined. When the calculated value of c exceeds 4 mm (c> 4 mm), it can be determined that the penetration is excessive.

  FIG. 45 is an example of an image diagram showing detection of the size (depth) of the undercut 40 by the slit light cutting type sensor 41.

  When the torch position shift amount (first and second distances S1 and S2) is increased and welding is performed, the throat thickness L of the welded portion increases, but near the bead toe portion of the heat transfer copper fin 3 (at the point a). Undercut 40 (dent) may occur on the top. Therefore, in addition to the bead vertical height H, in order to inspect the presence and depth R of the undercut 40, the slit light cutting sensor 41 and the image processing device 43 are used to check the undercut above the point a of the line image 46. The presence / absence of 40 and the depth R are detected.

  That is, the inflection portion between the surface line aa point-a point of the heat transfer copper fin 3 is determined as the f point, and the concave portion between the a point and the f point is recognized as the undercut 40, and the depth R is determined. measure. For example, when the measured depth R of the undercut 40 is less than 0.5 mm (R <0.5 mm), it is judged as none or normal, and the depth R is in the range of 0.5 to 1 mm (0.5 ≦ R ≦ 1 mm), and when the depth R exceeds 1 mm (R> 1 mm), it is determined that it is excessive. When the depth R of the undercut 40 is too large, the welding quality is deteriorated and the heat conduction cross-sectional area necessary for heat removal is reduced.

  As described above, using the slit light cutting sensor 41 and the image processing device 43, the bead vertical height H of the weld surface portion is measured, and the throat thickness L is calculated from the measured bead vertical height H. By detecting and determining the presence / absence of the undercut 40 and the depth R, the welding quality can be managed.

  In addition, when the depth R of the undercut 40 exceeds 1 mm (R> 1 mm), as shown in FIG. The undercut 40 can be eliminated by performing a repair that builds up one pass on the welded portion determined to be excessive and the upper portion in the vicinity (bead surface near the copper plate or near the bead toe). In addition, when the depth R of the undercut 40 is R ≧ 0.5 mm or more (R ≧ 0.5 mm), the welded portion determined to have the undercut 40 and the upper portion in the vicinity (bead surface near the copper plate or bead stop) By performing repair that builds up one pass in the vicinity of the edge), it is possible to eliminate undercuts of a size (R ≧ 0.5 mm) including those with a depth R of the undercut 40 being shallow. Even better.

  For example, in repair welding to be built up in one pass, as shown in FIGS. 3, 4 and 9, the welding conditions in which the welding current, the heat input, etc. are reduced compared to the welding conditions when the fillet joint is fully welded. Is repaired by repair welding processes 109, 116, 119, and 122, so that the overlay repair can be easily performed, and the undercut can be eliminated as described above.

  FIG. 46 shows an example of detection of the bead vertical height of the welded portion by the manually operated size measuring instrument as the seventh embodiment of the present invention.

  As shown in the figure, a dimension measuring device 48 is arranged on the surface of the base material of the inner cylinder 1, and a measuring needle 49 that can be moved up and down or up and down and back and forth by manual operation is attached to the bead toe 47 of the heat transfer copper fin 3. It is made to contact and the bead vertical height H of a weld bead part is measured for every specific interval, and is displayed on a display part.

  Thus, by using the manually operated dimension measuring device 48, the bead vertical height H can be easily measured, and each value of the measured bead vertical height H is measured in the first and second experiments. By substituting into the equations (1) and (2), respectively, and calculating the values of the throat thickness L and the penetration depth c, the penetration depth inside the weld without destructive inspection. c can be easily estimated. In addition, if the bead toe 47 has the undercut 40, the depth R of the undercut 40 can also be measured, and quality can be determined from the depth R.

  As described above, when the calculated value of the throat thickness L calculated from the formula (1) of the first empirical formula is equal to or greater than the plate thickness T1 of the heat transfer copper fin 3 (L ≧ T1), it is acceptable. If the thickness is smaller than the plate thickness T1 of the heat transfer copper fin 3 (L <T1), it can be determined that the heat transfer copper fin 3 is unacceptable due to insufficient throat thickness or insufficient heat transfer area.

  When the calculated value of the penetration depth c calculated from the expression (2) of the other second empirical formula is in the range of 0.05 ≦ c ≦ 4 mm, it is determined to be acceptable, and the penetration depth When the calculated value of c is less than 0.05 mm (c <0.05 mm), it is determined that the welded portion on the inner cylinder 1 and / or outer cylinder 2 side is insufficiently bonded or insufficient in strength, and the penetration depth When the calculated value of c exceeds 4 mm (c> 4 mm), it can be determined that the penetration is excessive.

  As described above, according to the present embodiment, the weldability of the dissimilar joint between copper and steel is excellent, the throat thickness L having a sufficient size and a heat conduction cross-sectional area effective for heat removal can be secured, and It is possible to obtain a weld bead and a weld cross section having good quality free from defects such as cracks, and to contribute to an improvement in heat removal performance and a reduction in manufacturing cost.

  In addition, according to the present embodiment, by performing correction control of the torch position based on the positional deviation detection data, the horizontal and vertical misalignments (ΔYn, Zn) between the weld line position and the torch position are eliminated. It is possible to obtain a good weld bead having no defective bead that is out of the weld line. In addition, by measuring the bead vertical height H from the surface of the weld bead and substituting the measured bead vertical height H into the approximate empirical formula, the throat thickness L, the penetration depth c, and the like are calculated. Without inspecting, it is possible to easily estimate the throat thickness L, the penetration depth c, and the like inside the weld, and to determine whether the welding quality is acceptable.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Inner cylinder, 2 ... Outer cylinder, 2-2 ... Outer cylinder board, 3 ... Heat-transfer copper fin, 4 ... Space, 5-1, 5-2 ... 5-N, 8, 8-1 , 8-2... 8-N ... fillet joint, 6, 6-1, 6-2 ... 6-N, 9-1, 9-2 ... 9-N ... weld line, 7 ... inner weld, 7-1, 7-2 ... 7-N, 10-1, 10-2 ... 10-N ... weld bead and weld cross section, 10 ... outer weld, 11 ... TIG -MIG welding torch, 12 ... TIG unit, 13 ... non-consumable electrode, 14 ... first shield gas, 15 ... TIG welding power source, 17 ... MIG unit, 18 ... consumable wire, 19 ... second shield gas, 20, 28 ... MIG welding power source, 16-1, 16-2, 21-1, 21-2, 29-1, 29-2 ... feeder cable, 22 ... TIG arc, 23 ... MIG arc, 24 Melting pool, 25 ... welding direction, 26 ... MIG welding torch, 27 ... MIG shielding gas, 30 ... overlay repair part, 31 ... long arm, 32 ... guide roller, 33, 34, 35 ... mounting jig, 36 ... 2-axis drive table, 37 ... shielding plate, 38 ... inclined surface shape, 39 ... flat surface shape, 40 ... undercut, 41 ... slit light cutting sensor, 42 ... slit light beam, 43 ... image processing device, 44 ... image Monitor, 45-1, 45-2, 46 ... line image, 47 ... bead toe, 48 ... dimension measuring instrument, 49 ... measuring needle, 51 ... distance sensor, 52 ... distance measuring light, 53 ... sensor container, 54 ... Distance sensor controller, 55 ... Distance measurement monitor, 56-1, 56-2 ... 56-N ... Temporary welded part, 99 ... Welding procedure of heat transfer copper fin (1), 100 ... Heat transfer Copper Fin Welding Procedure (Part 2 101 ... Welding procedure of heat transfer copper fin (No. 3), 102 ... Wire welding cross-sectional area determining step, 103 ... First welding step on the inner cylinder side, 105 ... Repetitive welding step of welding N points on the inner cylinder side , 106... Repeated welding process of welding and inspection in a small number unit on the inner cylinder side, 107, 117... Inspection process on the inner cylinder side, 109, 116, 119, 122 ... Repair welding process, 110 ... Second on the outer cylinder side 112 ... Repeat welding process of welding of N places on the outer cylinder side, 113 ... Repeat welding process of welding and inspection in the minor unit on the outer cylinder side, 114, 120 ... Inspection process on the outer cylinder side, 123 ... Outer cylinder welding finishing process, 201 ... welding control device, 311 ... drive device.

Claims (23)

Inclined at substantially equal intervals in the circumferential direction between a steel inner cylinder that houses a collection of spent fuel containing radioactive material and a steel outer cylinder that is coaxially disposed outside the inner cylinder When welding a plurality of heat transfer copper fins made of copper, each end face portion of the predetermined number of heat transfer copper fins is abutted at substantially equal intervals in the longitudinal direction of the outer surface of the inner cylinder made of steel, respectively. Each outer joint formed by abutting each other end face portion of the heat transfer copper fins at a substantially equal interval in the longitudinal direction of the inner cylindrical inner surface or each of the fillet joint portions having a wide-angle inclination on the inner cylinder side. Welding is performed on each fillet joint portion having a wide-angle inclination on the cylinder side, or on each fillet joint portion formed on both surfaces of the inner cylinder and the outer cylinder by composite welding of the preceding TIG and the succeeding MIG or MIG welding. A method for welding a heat transfer copper fin for a metal cask,
Wire feed speed or wire feed speed so that the throat thickness is not less than a predetermined size when the minimum distance from the molten bottom on the heat transfer copper fin side to the weld bead surface is the throat thickness of the weld The wire welding cross-sectional area is determined from the wire diameter and a predetermined welding speed, and a CuSi wire is used for the welding line for each path to be welded from the welding start position to the end position of each fillet joint, A welding method for heat transfer copper fins for metal casks, wherein welding is performed one pass at a time by composite welding of the preceding TIG and the subsequent MIG or the MIG welding. In the welding method of the heat-transfer copper fin for metal casks of Claim 1,
At the welded portion of each fillet joint that has been welded, at least the throat thickness L is formed to be equal to or greater than the plate thickness T1 of the heat transfer copper fin, and the inner tube side or the outer tube side made of steel or The welding depth c on both sides of the inner cylinder and the outer cylinder is formed in a range of 0.05 ≦ c ≦ 6 mm. Inclined at substantially equal intervals in the circumferential direction between a steel inner cylinder that houses a collection of spent fuel containing radioactive material and a steel outer cylinder that is coaxially disposed outside the inner cylinder When welding a plurality of heat transfer copper fins made of copper, each end face portion of the predetermined number of heat transfer copper fins is abutted at substantially equal intervals in the longitudinal direction of the outer surface of the inner cylinder made of steel, respectively. Each outer joint formed by abutting each other end face portion of the heat transfer copper fins at a substantially equal interval in the longitudinal direction of the inner cylindrical inner surface or each of the fillet joint portions having a wide-angle inclination on the inner cylinder side. Welding is performed on each fillet joint portion having a wide-angle inclination on the cylinder side, or on each fillet joint portion formed on both surfaces of the inner cylinder and the outer cylinder by composite welding of the preceding TIG and the succeeding MIG or MIG welding. A method for welding a heat transfer copper fin for a metal cask,
Wire feed speed or wire feed speed so that the throat thickness is not less than a predetermined size when the minimum distance from the molten bottom on the heat transfer copper fin side to the weld bead surface is the throat thickness of the weld A wire welding amount determining step for determining a wire welding cross-sectional area from the wire diameter and a predetermined welding speed, and butting one end surface portion of the predetermined number of heat transfer copper fins at substantially equal intervals in the longitudinal direction of the outer surface of the inner cylinder. After N fillet joint portions having a wide angle are formed, CuSi wires are used to weld one pass to each fillet joint portion on the inner cylinder side by composite welding of the preceding TIG and the following MIG or the MIG welding. After the first welding step on the inner cylinder side and the end of welding on the inner cylinder side or the end of welding on the inner cylinder side and the inspection of the welded portion, the outer cylinder is placed on the outer peripheral side of the heat transfer copper fin. Arrange the inner surface of the outer cylinder After joining the other end face portions of the heat transfer copper fins of the predetermined number of sheets in the longitudinal direction to form wide-angle inclined fillet joint portions, composite welding of the preceding TIG and the subsequent MIG using the CuSi wire Or a second welding step on the outer cylinder side for welding one pass at a time to each fillet joint on the outer cylinder side by the MIG welding. Method. In the welding method of the heat transfer copper fin for metal casks of Claim 3,
In the first welding step and the second welding step, at least the throat thickness L is formed to be equal to or greater than the plate thickness T1 of the heat transfer copper fin at the welded portion of each fillet joint, and the steel is made of steel. The metal cask heat transfer is characterized in that a penetration depth c on the inner cylinder side or the outer cylinder side or both sides of the inner cylinder and the outer cylinder is formed in a range of 0.05 ≦ c ≦ 6 mm. Copper fin welding method. Inclined at substantially equal intervals in the circumferential direction between a steel inner cylinder that houses a collection of spent fuel containing radioactive material and a steel outer cylinder that is coaxially disposed outside the inner cylinder When welding a plurality of heat transfer copper fins made of copper, each end face portion of the predetermined number of heat transfer copper fins is abutted at substantially equal intervals in the longitudinal direction of the outer surface of the inner cylinder made of steel, respectively. Each outer joint formed by abutting each other end face portion of the heat transfer copper fins at a substantially equal interval in the longitudinal direction of the inner cylindrical inner surface or each of the fillet joint portions having a wide-angle inclination on the inner cylinder side. Metal to be welded to each fillet joint portion with a wide-angle inclination on the cylinder side, or to each fillet joint portion formed on both surfaces of the inner cylinder and the outer cylinder, by composite welding of preceding TIG and subsequent MIG or MIG welding A welding method for heat transfer copper fins for cask,
Wire feed speed or wire feed speed so that the throat thickness is not less than a predetermined size when the minimum distance from the molten bottom on the heat transfer copper fin side to the weld bead surface is the throat thickness of the weld Wire welding amount determination step for determining the wire welding cross-sectional area from the wire diameter and a predetermined welding speed;
After a predetermined number of heat transfer copper fins on one end surface of the inner cylinder outer surface are abutted at substantially equal intervals to form N wide fillet joints, CuSi wire is used to form the preceding TIG A step of welding one pass at a time to each fillet joint on the inner cylinder side by composite welding of the MIG and the subsequent MIG or the MIG welding, or a predetermined number of the heat transfer copper fins in the longitudinal direction of the outer surface of the inner cylinder After the N-side end face part is abutted at substantially equal intervals to form the wide-angle-inclined fillet joint part at N places, the N fillet joint parts are preliminarily divided into units of 1 to 5 places, and the divided 1 A process of repeating welding and inspection of the fillet joint part so as to inspect the welded part, and welding a predetermined number of the heat transfer copper fins while performing welding on the fillet joint part in units of 5 units. Divide in advance, and the divided unit After forming the fillet joint part by butting one end face part of the heat transfer copper fin to the outer surface of the inner cylinder, forming the welded joint part and inspecting the welded part, welding and inspection And a first welding step on the inner cylinder side that performs any of the steps of repeating
After completion of welding on the inner cylinder side or after completion of welding on the inner cylinder side and completion of inspection of the welded portion, the outer cylinder is arranged on the outer peripheral side of the heat transfer copper fin, and predetermined in the longitudinal direction of the inner surface of the outer cylinder After joining the other end face portions of the number of the heat transfer copper fins to form N portions of wide-angle inclined fillet joint portions, the CuSi wire is used during welding, and combined welding of the preceding TIG and the subsequent MIG or the A step of welding one pass at a time to each fillet joint on the outer tube side by MIG welding, or a wide angle by abutting each other end surface portion of the predetermined number of heat transfer copper fins in the longitudinal direction of the inner surface of the outer tube After forming N fillet joints with an inclination, the N fillet joints are divided in advance and welded to the fillet joints of the divided units, and the welds are inspected. Repeatedly weld and inspect the fillet joint. Or in place of the outer cylinder, a plate-like outer cylinder plate that has been divided into a plurality of sheets is used, and the other of the heat transfer copper fins corresponding to the longitudinal direction of the inner surface of the plate-like outer cylinder plate is used. After the end face part is abutted to form a wide-angle inclined fillet joint part, welding is performed on the fillet joint part, and the formation, welding, and inspection of the fillet joint part are repeated so as to inspect the welded part. And a second welding step on the outer cylinder side for performing any one of the steps. A welding method for heat transfer copper fins for metal casks. In the welding method of the heat-transfer copper fin for metal casks of Claim 5,
When using the plate-shaped outer cylinder plate divided into a plurality of pieces in advance, the plurality of outer cylinders are formed after the step of repeating the formation, welding, and inspection of the fillet joint portion divided into a small number of units. A metal cask transmission characterized by further comprising an outer cylinder welding finishing step of welding each connecting portion of both sides of the plate in the width direction to finish the outer cylinder structure in an integral cylindrical or polygonal cylinder shape. Hot copper fin welding method. In the welding method of the heat transfer copper fin for metal casks of Claim 5 or 6,
In the first welding step and the second welding step, at least the throat thickness L is formed to be equal to or greater than the plate thickness T1 of the heat transfer copper fin at the welded portion of each fillet joint portion, and the steel is made of steel. The heat transfer copper for a metal cask, wherein a penetration depth c on the inner cylinder side or the outer cylinder side or both sides of the inner cylinder and the outer cylinder is formed in a range of 0.05 ≦ c ≦ 4 mm. Fin welding method. In the welding method of the heat transfer copper fin for metal casks of any one of Claims 1 thru | or 7,
When the heat transfer Netsudo thickness T1 of the fins is 5mm, the CuSi wire wire welding sectional area Aw is 30 mm ² or more 55 mm ² or less ^{(30 ≦ Aw ≦ 55mm 2)} , the welding heat input Q is 12 kJ / cm or more While using the condition of 35 kJ / cm or less (12 ≦ Q ≦ 35 kJ / cm), the position where the position of the CuSi wire or the torch position is shifted to the surface side of the heat transfer copper fin by a predetermined distance should be welded For a metal cask characterized in that it is determined to be a weld line of a fillet joint part, and then welded to the weld line of the fillet joint part by composite welding of the preceding TIG and subsequent MIG or the MIG welding Welding method for heat transfer copper fins. In the welding method of the heat transfer copper fin for metal casks of any one of Claims 1 thru | or 8,
Instead of the throat thickness L, the following first empirical formula (1) showing the relationship between the bead vertical height H and the throat thickness L is used, from the steel side surface near the weld bead to the copper side. The bead vertical height H up to the weld bead toe is measured by the measuring means, and the value of the bead vertical height H measured by the measuring means is substituted into the first empirical formula (1) to determine the inside of the weld. The value of the throat thickness L is calculated, and it is determined whether or not the calculated value of the throat thickness L satisfies the L ≧ T1. Welding method.
First empirical formula: L≈b1 × H (1)
However, b1 is a constant of 1. In the welding method of the heat transfer copper fin for metal casks of Claim 9,
When the calculated value of the throat thickness L calculated by the first empirical formula (1) is smaller than the plate thickness T1 of the heat transfer copper fin (L <T1), or the throat thickness L measured from the weld cross section. A welding method for heat transfer copper fins for metal casks, wherein when the measured value of L <T1, the throat thickness is insufficient or the heat transfer area is insufficient. In the welding method of the heat transfer copper fin for metal casks of Claim 10,
When the throat thickness L is smaller than the plate thickness T1 of the heat transfer copper fin (L <T1), in the repair welding process for repairing the defective part, the corresponding welded part with insufficient throat thickness or insufficient heat transfer area and its A method of welding a heat transfer copper fin for a metal cask characterized by repairing by building up one pass on the upper part of the vicinity. In the welding method of the heat transfer copper fin for metal casks of any one of Claims 1 thru | or 8,
In place of the penetration depth c, the bead vertical height H is measured using the following second empirical formula (2) showing the relationship between the bead vertical height H and the penetration depth c. And the value of the bead vertical height H measured by the measuring means is substituted into the second empirical formula (2) to calculate the value of the penetration depth c inside the weld. It is determined whether or not the value of the penetration depth c satisfies the predetermined 0.05 ≦ c ≦ 6 mm, or the relationship between the previously prepared throat thickness L and the penetration depth c is shown below. 3 and the following first experimental formula (1) showing the relationship between the bead vertical height H and the throat thickness L, the measured value of the bead vertical height H is The value of the throat thickness L inside the weld is calculated by substituting it into the first empirical formula (1), and the calculated value of the throat thickness L is substituted into the third empirical formula (3). A metal characterized by calculating a value of a penetration depth c inside the contact and determining whether or not the calculated value of the penetration depth c satisfies a predetermined 0.05 ≦ c ≦ 6 mm Welding method for heat transfer copper fin for cask.
First empirical formula: L≈b1 × H (1)
Second empirical formula: C = b2 × H ³ + b3 × H ² + b4 × H + b5 (2)
Third empirical formula: C = b6 × L ³ + b7 × L ² + b8 × L + b9 (3)
However, b1 is a constant, b2 is a constant of -0.0067, b3 is a constant of 0.22, b4 is a constant of -2.62, b5 is a constant of 10.3, and b6 is a constant of -0.0067. B7 is a constant of 0.24, b8 is a constant of -2.87, and b9 is a constant of 11.4. In the welding method of the heat transfer copper fin for metal casks of Claim 12,
When the calculated value of the penetration depth c calculated by the second empirical formula (2) or the third empirical formula (3) is less than 0.05 mm, or the deepest on the steel side measured from the weld cross section When the measured value of the penetration depth c of the portion is less than 0.05 mm, it is determined that the welded portion on the steel side is insufficiently bonded or insufficiently strong. Welding method. In the welding method of the heat transfer copper fin for metal casks of any one of Claim 9 thru | or 13,
The means for automatically measuring the bead vertical height H is a slit light cutting type sensor, and the slit light cutting type sensor is disposed at an upper position on the surface of the weld bead after the end of welding, and the welding bead on the welding start side is arranged. The slit light cutting type is moved on the welding line from the surface position to the welding bead surface position on the welding end side, or moved backward on the welding line in the direction of the welding start side from the direction on the welding end side. Let the sensor perform a detection action,
A line image representing the shape of the weld bead surface portion and the vicinity thereof from the slit light cutting type sensor is taken into an image processing apparatus at substantially constant time intervals or at substantially constant distances, and subjected to image processing. Draw an extended straight line by extending the straight part of the surface part in the direction of the bead toe part, and determine the point of intersection of the other bead toe part intersecting with the straight part of the other copper side base metal surface part as a point , A position where a straight line drawn in a direction perpendicular to the point a and the extended line intersects the extension line at a right angle is determined as a point d, and a distance between the points a and d (a point−d Point), the measured distance (point a-point d) is specified as the value of the bead vertical height H, and the value of the bead vertical height H is determined as the first empirical formula (1). A method for welding a heat transfer copper fin for a metal cask, wherein the value of the throat thickness L inside the weld is calculated by substituting In the welding method of the heat-transfer copper fin for metal casks of Claim 14,
The slit light cutting sensor and the image processing apparatus detect the presence or absence of the undercut and the depth R in the vicinity of the point a, determine the inflection portion of the surface line of the copper side base material as the point f, Recognize the undercuts at points a and f as undercuts, measure the depth R of the undercut, and determine that there is no undercut or normal when the measured depth R is less than 0.5 mm, When the depth R is 0.5 to 1 mm, it is determined that there is an undercut, and when the depth R exceeds 1 mm, it is determined that the undercut is excessive. Method. In the welding method of the heat transfer copper fin for metal casks of Claim 15,
When the depth R of the undercut exceeds 1 mm (R> 1 mm), in the repair welding process for repairing the defective part, one pass is built up and repaired at the upper part of the welded part where the undercut is excessive. A method for welding a heat transfer copper fin for a metal cask. In the welding method of the heat transfer copper fin for metal casks of any one of Claims 1 thru | or 8,
A slit light is formed at a position in front of the integrated TIG-MIG welding torch for performing composite welding of the preceding TIG and the subsequent MIG or the MIG welding torch for performing the MIG welding, and above the weld line of the fillet joint. In the case where a cutting type sensor is provided to detect the displacement of the welding line, a linear line image representing the shape of the fillet joint portion during the progress of welding is substantially omitted from the slit light cutting type sensor to the image processing apparatus. Image capturing is performed at regular time intervals or at substantially constant distances, and the b point position corresponding to the end face corner of the heat transfer copper fin is detected, and the surface side of the heat transfer copper fin from the b point position is detected. P point position shifted by a predetermined distance S1 is detected,
From the position coordinates Pn (Yn, Zn) of the detected P point and the b point position of the end face corner portion of the heat transfer copper fin at the welding start position X0 detected in advance before welding, the surface of the heat transfer copper fin From the deviation (Pn (Yn, Zn) -P0 (Y0, Z0)) from the origin position coordinate P0 (Y0 = 0, Z0 = 0), where the P0 point position shifted by the predetermined distance S1 is set as the zero origin. The horizontal position deviation ΔYn and the vertical position deviation Zn are calculated, and detected in advance by the slit light cutting sensor and the image processing device based on the detection data of the calculated positional deviations (ΔYn, ΔZn). At the point where the subsequent TIG-MIG welding torch or the MIG welding torch arrives at or near the position Xn in the weld line direction, the TIG in the direction to eliminate the horizontal / vertical displacement (ΔYn, ΔZn), respectively. -MI Welding torch or the welding method of the metal cask Den Netsudo fins and performs control to correct the position of the MIG welding torch. In the welding method of the heat transfer copper fin for metal casks of Claim 17,
The correction of the lateral displacement ΔYn is based on the detection data of the lateral displacement detected by the slit light cutting sensor and the image processing device, and the TIG-MIG welding torch in the direction to eliminate the displacement ΔYn. Control to correct the position of
On the other hand, the other vertical misalignment correction uses a TIG arc voltage signal on the preceding TIG side in place of the vertical misalignment ΔZn of the detection data, and previously calculates a TIG arc voltage necessary for maintaining a desired arc length. The first reference voltage value V1 determined by measurement and the TIG arc voltage signal on the preceding TIG side during welding progress are detected and averaged in real time by the voltage detection means, and the averaged TIG arc voltage detection is performed. A deviation voltage ΔV1 (Vn−V1) with respect to the signal value Vn is detected, and control is performed to correct the position of the TIG-MIG welding torch vertically so as to eliminate the deviation voltage ΔV1.
Alternatively, one molten pool is formed by the TIG arc on the preceding TIG side generated at the welding start position and the MIG arc on the subsequent MIG side generated near the rear of the TIG arc, and the one molten pool in the weldable state is formed. Immediately after moving in the welding line direction or after a predetermined time has elapsed, the average value obtained by detecting the TIG arc voltage signal on the preceding TIG side for a predetermined time is determined as the second reference voltage value V2 and detected in real time while welding is in progress Further, a deviation voltage ΔV2 (Vn−V2) between the value Vn of the TIG voltage detection signal to be averaged and the second reference voltage value V2 is detected, and the TIG-MIG welding is performed so as to eliminate the deviation voltage ΔV2. A method for welding a heat transfer copper fin for a metal cask, wherein control is performed to correct the position of the torch in the vertical direction. In the welding method of the heat transfer copper fin for metal casks of Claim 17 or 18,
When a plurality of tack welds are intermittently formed on the fillet joint, the slit light cutting sensor and the image processing device remove the fillet weld from the fillet joint where the tack weld is located. The embedded line image does not have the b point position corresponding to the end face corner of the heat transfer copper fin, and has a temporary bead toe portion and a temporary bead surface curve. Recognize it as a recognized or abnormal part, treat the detection data of this tack welded part as non-adopted and keep the torch position as it is,
On the other hand, since the line image taken from the fillet joint portion having no other tack welded portion has the b point position corresponding to the end face corner of the heat transfer copper fin, the b point position is detected. At the same time, the position coordinate Pn (Yn, Zn) of the P point shifted from the position b by the predetermined distance S1 to the surface side of the heat transfer copper fin is detected, and the position coordinate Pn of the P point and the origin position coordinate P0 are detected. The position deviation (ΔYn, ΔZn) is calculated from the deviation from (Y0 = 0, Z0 = 0) and adopted, and based on the detection data of this positional deviation (ΔYn, ΔZn), the position in the weld line direction detected in advance is used. At the point where the subsequent welding torch arrives at or near Xn, correct the torch position in the direction to eliminate the horizontal / vertical displacement (ΔYn, ΔZn), or eliminate the horizontal displacement ΔYn. Characterized by correcting the torch position Welding method Netsudo fin Den metal cask. In the welding method of the heat transfer copper fin for metal casks of any one of Claims 17 thru | or 19,
Instead of the slit light cutting type sensor, a distance sensor capable of measuring a distance is used, and an integrated structure arranged in a substantially downward posture at the distal end of a long arm that can move and move in the weld line direction of the fillet joint The TIG-MIG welding torch or the inner cylinder located at a front position of the MIG welding torch or a position behind the rotationally movable guide roller disposed at a position preceding the welding torch and separated from the welding line by a short distance One of the distance sensors is disposed at an upper position in a direction substantially perpendicular to the surface on the side or the surface on the outer cylinder side, or an upper position in a direction substantially perpendicular to the surface on the inner cylinder side or the surface on the outer cylinder side, The distance sensors are arranged one by one on the surface on the side of the heat transfer copper fin that is separated from the weld line by a short distance and at an upper position in a substantially right angle direction,
During the running operation and welding operation of the TIG-MIG welding torch or MIG welding torch, based on the distance measured by the distance sensor and the measurement data of the change in the distance, it follows the position Xn in the welding line direction measured in advance. At the point where the welding torch reaches or near the point, the torch position is corrected in a direction that eliminates the positional deviation in the horizontal direction and the vertical direction due to bending or deformation in the weld line direction of the fillet joint portion. Welding method of heat transfer copper fin for metal cask. In the welding method of the heat transfer copper fin for metal casks of any one of Claims 17 thru | or 20,
At least a shielding plate capable of shielding radiant heat and scattered matter is used, and the shielding plate is an integral TIG-MIG welding torch or MIG welding torch for welding in the weld line direction of the fillet joint portion, and the TIG-MIG It is located between the welding torch or the slit light cutting sensor that detects displacement at a position ahead of the MIG welding torch or the distance sensor that measures the distance change, and is long at the upper position substantially perpendicular to the tangent line. A method for welding a heat transfer copper fin for a metal cask, characterized in that it is disposed under the tip of a shank arm. A steel inner cylinder that houses an assembly of spent fuel having a radioactive substance, a steel outer cylinder that is coaxially disposed outside the inner cylinder, and between the inner cylinder and the outer cylinder With a plurality of copper heat transfer copper fins inclined and arranged at substantially equal intervals in the circumferential direction,
Each fillet joint portion having a wide-angle inclination on the inner cylinder side formed by abutting one end face portions of the heat transfer copper fins at substantially equal intervals in the longitudinal direction of the outer surface of the inner cylinder made of steel, or Each outer joint side wide-angle inclined fillet joint portion formed by abutting the other end face portions of the predetermined number of heat transfer copper fins at substantially equal intervals in the longitudinal direction of the inner cylinder inner surface, or the inner cylinder And a metal cask with heat transfer copper fins formed by welding each fillet joint formed on both surfaces of the outer cylinder, one pass at a time by composite welding of the preceding TIG and the subsequent MIG or MIG welding. And
A plate having a heat transfer copper fin having a throat thickness L of at least the throat thickness L at a welded portion of each fillet joint portion welded by one pass by a composite welding of the preceding TIG and the subsequent MIG or the MIG welding using a CuSi wire. It is formed in thickness T1 or more, and the penetration depth c of the steel inner cylinder side or the outer cylinder side or both sides of the inner cylinder and the outer cylinder is formed in a range of 0.05 ≦ c ≦ 4 mm. A metal cask with heat transfer copper fins. A metal cask with a heat transfer copper fin according to claim 22,
When the plate thickness T1 of the heat transfer copper fin is about 5 mm, the wire welding cross-sectional area Aw of the CuSi wire is 30 mm ^{2 to} 55 mm ² (30 ≦ Aw ≦ 55 mm ² ), and the welding heat input Q is 12 kJ / cm. More than 35 kJ / cm or less (12 ≦ Q ≦ 35 kJ / cm) is used, and the fillet joint is welded and formed by composite welding of the preceding TIG and subsequent MIG or MIG welding. A metal cask with heat transfer copper fins.

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