JPH0957449A - Welding repair method for metallic member and cladding by welding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To repair or correct fine parts by the cladding by welding method with excellent quality by loading a welding material on the part to be repaired of the metallic member, energizing it with large current in the pulse form to form the dot-shaped deposited metal, and achieving the re-melting by the arc. SOLUTION: Appropriate amount of the fine welding powder is loaded on the part to be repaired of a metallic member 1, or a thin-plate shaped welding material is placed thereon. The tip of a primary electrode 8 is pressed against the welding material, the large current of 300-1500A is energized in the pulse- form to form the dot-shaped deposited metal. Cladding by welding is achieved by moving the primary electrode 8 to continue or duplicate the weld metal. Then, the inert atmosphere is realized, and a power supply switch 5 of an arc welding machine is turned on. A primary electrode 10 is brought close to the cladded deposited metal at the part to be repaired of the metallic member 1, and the arc radiation is realized for a short time to re-melt the deposited metal. Alter the cladded by welding part is solidified, the excessive metal is removed and the finish is achieved by the grinding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention repairs relatively minute damages, dimensional errors, etc., which have occurred in metal members represented by molding dies such as rubber products or synthetic resin products by overlay welding. , A correction method and a build-up welding apparatus used for carrying out the method.

[0002]

2. Description of the Related Art Molding dies are routinely damaged, dimensional errors, and the like during the manufacturing stage and the process of use. The need to correct and repair damage and dimensional errors to recycle the mold is enormous, especially in terms of cost. As a conventional correction and repair method, overlaying by argon welding is generally carried out. In this method, a welding rod is continuously melted by an arc in an argon gas atmosphere, a weld pool formed in a repaired portion of a metal member is subjected to build-up welding, and after solidification, surplus thickness is removed and polishing is performed to finish. However, the above-mentioned build-up by argon welding is 6000 ° C to 80 ° C.
Since the arc heat at a high temperature of 00 ° C is continuously generated to melt the welding rod, the metal member has defects such as sink marks, deformation, and discoloration, which have a bad influence on the heat. The actual situation is that it cannot be applied to repair parts.

Other correction and repair methods include (a) silver brazing, (b) plating build-up, (c) tapping,
(D) Applications such as nested embedding are known. Although each of these methods has advantages, it involves various problems and restricts the active implementation of mold correction and repair. For example, the above (a), (b),
The repair method of (c) has poor durability of finish. With the repair methods (b) and (d), the work takes too much time. Further, there is a problem that a skilled technique is required to carry out the repairing method (c). Also, the above-mentioned repair methods (a) to (d) are not suitable for implementation in fine repair points.

Next, JP-A-5-261585 and JP-A-5-261586 (US Pat. No. 5,378,867)
(Specification and Drawing), a secondary electrode is connected to a metal member typified by a synthetic resin molding die for the purpose of comparatively fine crushing, scratching, size correction, etc. Place an appropriate amount of fine-grained powdered welding powder on the repaired part or apply a thin plate-shaped welding material and locally press the primary electrode onto the welding powder or the welding material.
Approximately 1/1000 high current of about 1500 amps
〜4 / 1000 seconds within a short time to energize in a pulse shape to form a spot-shaped weld metal (nugget) on the surface of the metal member, and to form a spot-like or line-like weld metal on the repaired portion. Weld to build up in a shape, cut off unnecessary parts of the build-up welding (excess) after solidification, and polish and finish the marks.
A method for welding and repairing a metal member and an overlay welding apparatus are disclosed. According to the welding repair method and the overlay welding apparatus, the welding force (alloying degree) of the deposited metal is strong, durable, and does not peel off, and it is possible to weld an alloy having durability close to that of the original metal member. .

However, when the above-mentioned build-up weld portion (deposited metal) is enlarged and observed in detail with a micrograph or the like, the degree of deposition (alloying degree) reaches about 95%, but 100%. It turned out that not. Further, the degree of welding varies depending on the skill of the builder. This is because the weld metal (nugget) that can be formed by energizing one pulse with the primary electrode of the overlay welding device.
Has a fine dot-like shape with a diameter of about 0.6 to 1 mm, and since build-up welding is performed by continuously or stacking the dot-like nuggets, feeding (movement) of the primary electrode is performed. This is because the nugget will be in a non-continuous welded state due to a slight deviation in the operation. If the degree of welding is insufficient as described above, the welded portion (welded metal) that has been built up may peel off and the repaired product may be ruined.

[0006]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to finely correct and repair a metal member by applying a build-up welding which can be preferably carried out on a repaired part without giving any adverse thermal effect to the metal member. And a build-up welding apparatus. The ultimate object of the present invention is to obtain a welded portion (deposited metal) having a welded degree of close to 100% and high quality without fear of peeling. Therefore, the durability of the repaired portion is excellent, and the work time required for correction and repair is high. It is an object of the present invention to provide a method for repair and correction which is short and requires no skill, and a build-up welding apparatus used for carrying out the method.

[0007]

As a means for achieving the above object, the welding repair method according to the invention of claim 1 is to mount an appropriate amount of fine powder welding powder on the repaired portion of the metal member. Alternatively, a thin plate-shaped welding material is applied, and the primary electrode of the welding machine is locally pressed against the welding powder or the welding material so that a large current of 300 to 1500 amperes is 1/1.
It is necessary to make a point-like weld metal on a metal member by energizing it in a pulsed manner within a short time of 000 to 4/1000 seconds, and to make it possible to continuously or overlap the weld metal in a necessary range of a repaired portion. Of spot or line or surface build-up welding with various thicknesses, and the build-up weld part formed at the repaired part of the metal member as described above is placed in an inert gas atmosphere and arc-melted. The step of bringing the primary electrode of the machine closer to the build-up weld to radiate an arc for a short time to re-melt the deposited metal, and removing the surplus after the build-up weld has solidified and polishing the traces And a finishing step.

The build-up welding apparatus according to the invention of claim 2 is
It is composed of a combination of a welder for overlay welding a welding material to a metal member and an arc melter for remelting the overlay weld portion with an arc. The welder is electrically connected to the metal member.
Primary electrode with strength and shape that can be locally pressed against the secondary electrode and the welding powder in the form of fine-grained powder placed on the repaired part of the metal member or the thin plate-shaped welding material applied to the repaired part 30 between the electrode and the primary and secondary electrodes
High current of 0-1500 amps 1 / 1000-4 / 1
It consists of a power supply device that energizes in a pulsed manner within a short time of 000 seconds. The arc melting machine is a primary electrode for approaching a build-up weld formed on a metal member, and electrically connects with the metal member. Conductivity is provided between the secondary electrode to be connected and the secondary electrode and the primary electrode that is placed close to the build-up weld portion, and an arc is predetermined from the primary electrode to the build-up weld portion. It is characterized by comprising a power supply device for generating a current value in a range for a short time, and an inert gas supply mechanism for placing the build-up welded portion under an inert gas atmosphere before and after generating an arc. .

In the welding machine according to the second aspect, in the case of overlay welding the repaired portion of the metal member with powdered welding powder, a primary electrode having a built-in permanent magnet is used, and a magnetic fine particle powder is used. It is characterized in that welding powder is attached to the outer peripheral surface of the electrode. The welding machine according to claim 2 and the arc melting machine are characterized by an integrated structure in which respective power supply circuits are combined.

The welding machine and the arc melting machine according to the second aspect are characterized in that they are of a separate type in which respective power supply circuits are independent.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The welding repair method according to the invention of claim 1 is briefly described in Japanese Patent Laid-Open Nos. 5-261585 and 5-261586 (US Pat. No. 5,378,886).
No. 7 specification and drawings), a publicly known build-up welding device (hereinafter referred to as a welding machine) is used to fill a repaired portion of a metal member with a deposited metal to carry out a build-up of a necessary thickness, Then, the excess metal is put in a state of high temperature, and then the newly-developed "arc melting machine" is used to place the weld metal adhered to the repaired part of the metal member in the inert gas atmosphere to shorten the arc. It is carried out by the procedure of radiating for a time and remelting the deposited metal to form a molten pool. As a result, the welded portion was welded to the repaired portion of the metal member by overlay welding, but the weldability was partially insufficient (eg 95%).
The weld metal having a weld degree up to about 100% is completely melted by the arc heat of the arc melting machine to form a molten pool. Nuggets 100% alloyed in this way (filled meat)
After the solidification, the excess portion (extra thickness) is cut off and polished to achieve perfect welding repair.

The overlay welding apparatus according to the invention of claim 2 is
It is carried out by a combination of a "welding machine" for overlay welding the deposited metal to the metal member and an "arc melting machine" for remelting the deposited welded weld metal with arc heat. While the primary electrode of the welding machine forms a weld metal in a spot size of 0.6 to 1.0 mm by energizing for one pulse, the arc melting machine of 1
The arc of discharge is 5 to 10 of the deposited metal, that is,
A diameter of 3 to 5 mm and a thickness of 0.5 to 1 mm are broadly and instantaneously melted. Therefore, by radiating the arc uniformly to the build-up weld, the weld metal is
00% completely melted and alloyed. The nugget remelted and solidified by the arc of the arc melting machine is integrated into a nugget of about 5 to 10 times the size of the nugget formed by the welding machine.

The welding machine locally applies a secondary electrode electrically connected to a metal member, a welding powder in the form of fine particles or a thin plate-like welding material placed on a repaired portion of the metal member. A power source for applying a large current of 300 to 1500 amperes between the primary electrode having a strength and shape capable of being pressed and the primary and secondary electrodes within a short time of 1/1000 to 4/1000 seconds. And equipment. If necessary, a primary electrode having a structure in which a magnet piece is mounted in the electrode so that the welding powder in the form of fine powder is attached only at a suitable position of the primary electrode is used. Such a primary electrode is known from Japanese Utility Model Publication No. 7-19667.

Next, in the arc melting machine, a primary electrode for approaching the deposited metal (buildup welding) of the metal member to blow an arc, a secondary electrode electrically connected to the metal member, and the metal member. Electrical conductivity is imparted between the welded metal (nugget) welded and welded to the primary electrode and the primary electrode placed close to the welded metal.
The power supply device is configured to generate an arc from the primary electrode to the weld metal (nugget) at a current value within a predetermined range for a short time. The current value for generating an arc at the repaired portion of the metal member is 0 to 100 A, and the arc generation time is 0.0
It is about 1 to 1.0 seconds, particularly preferably 0.1 to 0.2 seconds. The primary electrode has a tapered shape. The primary electrode of the arc melting machine is held by a hand through a holder made of an insulating material, for example, a handle made of hard rubber, or is supported by a robot hand. The primary electrode of the arc melting machine is a tungsten electrode or the like that does not melt itself, and has a tapered shape so that directivity can be imparted to the arc. The most effective distance for bringing the primary electrode close to the deposited metal is about 0.5 mm. The current value is 0 to 70 A, especially 0 to 6 A
5A is the most desirable. The arc melting machine is provided with an inert gas supply mechanism for making the deposited metal into an inert gas atmosphere to prevent oxidation and the like.

The welding machine and the arc melting machine are classified into two types, a combined type in which an electric circuit (power circuit) having a power input and a control printed circuit board in common and a separate type in which an electric circuit is independently formed. Be proposed. The metal member to which the welding repair method of the present invention is applied is a metal member such as a synthetic resin molding die, a rubber molding die, a die casting die, and a glass die, and the material thereof is beryllium, copper alloy, aluminum. alloy,
Even steel, stainless steel, etc. can be applied.

Further, the repaired parts to which the present invention is applied include a parting line, wear, sagging, crushing, etc., which has occurred in the metal member, corners and edges of three vertices, and a small radius due to a design change. These are inner corners, secondary sink marks after argon welding, undercuts, pro holes, pits, pin holes, etc. The welding material employed in the practice of the present invention is in the form of powder alloy (welding powder), thin plate material, fine wire material, spherical material, paste, or the like. These are appropriately selected and used according to the size and shape of the repaired portion and other conditions. When a powder alloy (welding powder) is selected as the welding material, repair of corners and edges of the three vertices can be facilitated.

As the inert gas supplied by the above-mentioned inert gas supply mechanism, argon gas, helium gas and the like which have been conventionally used for preventing the oxidation and nitridation of the metal member and the welding material are suitable.

[0018]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a power supply circuit of a build-up welding apparatus in which a welding machine and a melting machine are combined. In the figure, P is the power supply circuit of the welding machine, and Q is the power supply circuit of the arc melting machine. This build-up welding device uses household AC100V as a power source,
It is provided with a control circuit printed circuit board 41 in charge of all control.

First, the welding machine P will be described. The power supply circuit for energizing the tapered primary electrode 8 and the secondary electrode 20 (which is common with the arc melting machine) electrically connected by means such as sticking to a metal member is the power switch 5
Turning on turns on the welding work of the welding material. One energization (one pulse) each time the operator steps on the foot switch 50 once.
Welding is performed. The magnitude of the welding voltage is a single coil with both ends connected to the AC line via the switch 50.
AC 0V-10V by voltage regulator 14 which is a transformer
Adjustments are made within a range of about. Foot switch 50
When is pressed once (switched on), the solid-state relay 15 is turned on by the control circuit 41, and the capacitors C1, C2, C3, C4 are charged. Subsequently, these capacitors are discharged by the thyristor 16 by the trigger operation of the control circuit 41, and the discharge current flows to the primary side of the transformer 17, so that a low voltage, large current (300A to 1500A) is generated on the secondary side of the transformer 17. Flow, which flows instantaneously from the primary electrode 8 to the secondary electrode 20 to perform welding. At this time, the current waveform that instantaneously flows in a pulse shape to the primary electrode 8 is as shown in FIG. 1 together, and the energization time (1/1000 to 4/1000) and the current value (300 A).
~ 1500A) is in an inversely proportional relationship. When the foot switch 50 is continuously depressed, the charging and discharging operations described above are intermittently repeated, and continuous welding can be performed. The cycle of the intermittent operation of charging and discharging is 0.3 seconds to 1 ... by the digital timer 18 which adjusts the relay control interval of the control circuit 41.
It is adjusted in the range of 5 seconds. The power supply circuit of FIG. 1 is manufactured as a lightweight and compact portable device.

When the overlay welding is manually performed on the repaired portion of the metal member, the primary electrode 8 is mounted on the insulating electrode holder 19 as shown in FIG. As shown in FIG. 3, a thin plate-shaped welding material 4 is applied onto the repaired portion 3 of the metal member 1, the electrode holder is grasped by the hand, and the tip of the primary electrode 8 is pressed against the welding material 4 and the welding material 4 shown in FIGS. Moving the thin plate-shaped welding material into the dent of the repaired portion 3 and turning on the foot switch 50 of the power supply device to 300A to 1000A.
A large current of A is applied in a pulsed manner to form a spot-shaped weld metal (nugget) on the repaired portion. A part of the dot shape of the welding material melted by energization is similarly alloyed into a dot-like melted metal member. Furthermore, the primary electrode 5 is advanced by a pitch corresponding to its diameter to make a large number of welded metals continuous or to be overlapped in multiple layers, so that a dot-shaped or linear-shaped or surface-shaped surface having a required thickness is provided over a necessary range of a repaired portion. Shape overlay welding. When mechanizing the welding work, the primary electrode 8 is attached to a robot hand or the like, and the auto switch 51 provided in the power supply unit is used.

9A to 9C show repair points 3 (FIG. 9) caused by abrasion, sagging, and crushing of the three vertexes of the metal member 1.
The process of repairing A) is shown. First, build-up welding 6 in the form of a dumpling having a necessary and sufficient size is performed in a range necessary for repairing the repaired portion 3 (FIG. 9B). It is convenient to use the square rod-shaped (or flat plate-shaped) primary electrode 8 shown in FIG. Thickness 0.2 mm,
A thin plate-shaped welding material 4 having a width of about 5 mm is applied in a direction crossing the repaired portion, the tip corner portion of the primary electrode 8 is pressed, and spot welding is performed to perform positioning of the welding material. Subsequently, the spot-like welding of the welding material 4 is repeated while moving the primary electrode 8 vertically and horizontally, and the build-up welding 6 is performed by making a large number of deposited metals (nuggets) continuous. Overlay welding 6
When the thickness is insufficient, the welding material 4 is folded back and the primary electrode is pressed onto the welding material 4 to continue the welding in such a manner that the nuggets are vertically overlapped. After that, the build-up welded portion 6 is re-melted by an arc melting machine, and after solidification, the surplus is scraped off by using a tool such as a scraper and polished by a grinder or a file to finish the corners of three vertices. 13 is restored to its original state (FIG. 9C).

When the ridgeline of the metal member 1 is to be repaired by welding, a thin plate-like welding material is applied along the ridgeline of the metal member 1 to be repaired, and the welding work is advanced while rolling the primary electrode 8 by a round bar. Is convenient (Fig. 5). 6 and 7 show a case in which a welding powder 4'in the form of fine-grained powder is used as the welding material, a permanent magnet 24 is built in the primary electrode 8, and the powder is attached to the outer peripheral surface of the electrode to perform build-up welding. ing. The primary electrode 8 is provided with a permanent magnet 24 (or an electromagnet) at the portion where welding powder 4'is attached and welding is performed. Of the primary electrode provided with a magnet, the non-magnetic material 25 is used except for the portion where the welding powder 2 is attached and welding is performed. Since the permanent magnet 24 is provided at the site where the welding powder 4'is attached and welding is performed, the magnetic powder acts on the outer peripheral surface of the welding powder 4'by magnetic action only by bringing it close to the magnetic welding powder 4'necessary for welding repair. It is attached. Therefore, the primary electrode 8 can be moved to the welding repair place 3 of the metal member 1 to perform welding. Permanent magnet 24
If the non-magnetic material 25 is formed in the primary electrode 8 provided with the non-magnetic material 25 except the portion where the welding powder 4'is attached, the required amount of welding powder 4'attaches only to the portion of the electrode required for welding. However, since the welding powder does not excessively adhere to the useless portion, the welding work can be performed quickly and surely. As shown in FIG. 7, the primary electrode 8 is moved while rolling to repeat the welding of the welding powder 4 ′, and a large number of dot-like deposited metals (nuggets) are made continuous and overlapped in multiple layers to perform overlay welding. . When the thickness of the overlay welding is insufficient, an appropriate amount of welding powder 4'is added.

Next, the arc melting machine Q will be described.
The primary electrode 10 and the secondary electrode 20 of the arc melting machine are detachably connected to the output terminals of the power supply device of FIG. 1 via cables 12 and 21 (see FIG. 8), respectively. The primary electrode 10 has a tapered pin shape to give directivity to the arc, and is attached to the holder 11 via a collet or the like (FIG. 8).

The weld metal 6 previously deposited on the repaired portion 3 of the metal member 1 by the welder P is supplied to the arc melting machine Q.
In order to prepare for the work for remelting, the secondary electrode 20 is first attached to an appropriate place of the metal member 1 to be electrically connected. After turning on the power switch 5 in FIG. 1 to activate the power circuit, the current value of the arc is set to 0 by the current regulator 42 which is a single winding transformer that receives the AC power voltage.
Adjust to 65A. Next, the primary electrode 10 is attached to the metal member 1
For the weld metal 6 welded to the repaired part 3 of
Bring it close to 0.5 mm and step on the foot switch 52 once. Then, according to a command from the printed circuit board 41, first, the automatic opening / closing valve 31 installed in the inert gas supply pipe 30 is opened,
The argon gas flows out, and the vicinity of the repair place 3 is made into an argon gas atmosphere by the argon gas. The argon gas supply pipe 30 may be implemented in a configuration integrated with the holder 11 of the primary electrode 10. Subsequently, the solid-state relay 43, which is a switching element, is activated, and a current flows through the input side 44 'of the main transformer 44 for a set short time (0.01 to 1.0 second). Next, the current generated on the output side 44 ″ by the electromagnetic induction of the main transformer 44 is converted into a direct current by the rectifier 45, and the capacitor C
It is smoothed at 5 and C6. After that, the high frequency generator 47 generates a high frequency under the control of the controller 41, the high frequency is boosted through the high frequency coupling transformer 48, and is superimposed on the direct current. Therefore, a high frequency (about 0.1 to 2 MHz) is applied between the primary electrode 10 and the metal member 1. That is, about 0.8 seconds after the foot switch 52 is stepped on (turned on), conductivity is imparted between the primary electrode 10 and the welding material 3, and the arc starts no-touch from the primary electrode 10. . Then, for about 2.5 seconds from the end of the arc, the automatic open / close valve 31 is also opened and the argon gas (after gas) flows out, so that the build-up welded portion 6 melted by the arc is placed under an inert gas atmosphere. keep. The controller 41 controls these operations. Reference numeral 49 in FIG. 1 denotes a high frequency bypass by the capacitors C5 and C6.
When the auto switch 51 is kept depressed, the above-mentioned operations are repeated at regular intervals, and remelting by the arc of the build-up welded portion can be continuously performed. The controller 41 receives an AC voltage as a drive voltage via the switch 5, the fuse F, and the transformer T1.

From the nugget 5 welded to the repaired portion 3 of the metal member 1 by the welding machine by the arc radiation once,
Ten pieces are completely melted and then solidified to re-form one raised dumpling-shaped weld overlay 6. FIG. 8 shows three build-up welded portions 6 formed by generating arcs three times. The arcs are overlapped by about 1/3 each to prevent the buildup interruption (occurrence of discontinuity). In this way, the same work is repeated until the build-up welded portion 6 covers the entire repaired portion 3. After that, the excess thickness is removed and the product is polished and finished.

When the power supply circuit of the arc melting machine is made to have a single structure, it becomes as shown in FIG. This is one in which only the portion Q in FIG. 1 is made independent. In the case of FIG. 10, the current detector 46 is inserted between the rectifier 45 and the transformer 48, and the controller 41 monitors the value of the arc current. Therefore, the controller 41 can make a correction when the arc current is not a desired value. Others are the same as those in FIG. 1, and thus the description is omitted.

While the preferred embodiment of the invention has been described above, various modifications can be made without departing from the spirit of the invention.

[0028]

According to the present invention, after the welding material is welded to the repaired portion of the metal member by the welding machine, the primary electrode of the arc melting machine is brought close to the welded welded portion (welded metal),
By operating the power supply device and radiating an arc to the weld metal at a predetermined current value for a short time, the weld metal is instantaneously remelted to form a molten pool and solidify.
% Remelting (alloying) can form a highly stable build-up weld. Overlay welding of deposited metal with a welding machine and radiating work of the arc with an arc melting machine (remelting)
By repeating the above, it is possible to obtain the necessary high-quality and highly stable build-up welded portion over the entire repaired portion. After that, by removing the excess thickness and polishing and finishing, high quality and highly stable repair and correction can be achieved.

The build-up welding of the welding material and the radiation of the arc are carried out within an extremely short time, and there is no thermal adverse effect such as sink mark, distortion, deformation, bending and discoloration on the metal member.
Since overlay welding is performed by alloying with a metal member and integrated, it does not peel off even when polished in units of 1/100 mm, the finished durability is good, and there is no troublesome operation for repair work. Therefore, the work does not take a long time, no skill is required, and the superiority or inferiority of the skill of the operator does not result in a difference in quality and finish. Furthermore, it is safe as it does not generate toxic gas, the amount of surplus material to be removed can be minimized to simplify the finish, and it is easy to recycle metal members such as molding dies, which has been a long-standing desire. It will certainly be achieved.

[Brief description of drawings]

FIG. 1 is a power supply circuit diagram of a build-up welding apparatus in which a welding machine and an arc melting machine are combined.

FIG. 2 is a front view of the primary electrode of the welding machine configured for manual work.

3A, 3B and 3C are elevational views showing a procedure of overlay welding using a thin plate-shaped welding material on the primary electrode.

FIG. 4 is a perspective view showing the procedure of build-up welding of the three vertex corners of the metal member.

FIG. 5 is a perspective view showing a procedure of build-up welding of a ridge line of a metal member.

FIG. 6 is a side view in which a main part of a primary electrode containing a magnet to which welding powder is attached is cut away.

FIG. 7 is a perspective view showing a procedure of overlay welding on a ridgeline of a metal member using the primary electrode.

FIG. 8 is a perspective view showing a procedure for remelting the build-up welded portion with the primary electrode of the arc melting machine.

9A to 9C are perspective views showing steps of a method for welding and repairing three corners of a metal member.

FIG. 10 is a power supply circuit diagram of an arc melting machine configured as a standalone type.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal member 3 Repair place 4 Welding material 4'Welding powder 6 Overlay welding part 8 Primary electrode 10 Primary electrode 20 Secondary electrode 24 Permanent magnet P Welding machine Q Arc melting machine

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location // B23K 9/04 8315-4E B23K 9/04 K

Claims (5)

[Claims] 1. An appropriate amount of fine-powder powder-like welding powder is placed on a repaired portion of a metal member or a thin plate-like welding material is applied, and a primary electrode of a welding machine is locally applied to the welding powder or the welding material. While pressing, a large current of 300 to 1500 amperes is applied in a pulse shape within a short time of 1/1000 to 4/1000 seconds to form a dot-like weld metal on the metal member, and a large number of the weld metals are continuously formed or A step of performing a spot-shaped or linear-shaped or surface-shaped build-up welding having a necessary thickness in a necessary area of the repaired part by overlapping, and the build-up welding formed in the repaired part of the metal member as described above. Part in an inert gas atmosphere, the primary electrode of the arc melter is brought close to the build-up weld to radiate an arc for a short time to re-melt the deposited metal, and after the build-up weld solidifies Remove excess meat and Wherein the finish polishing the marks, weld repair method of the metal member. 2. A combination of a welding machine for overlay welding a welding material to a metal member and an arc fusion machine for remelting the overlay weld portion with an arc, wherein the welding machine is electrically connected to the metal member. Secondary electrode,
A primary electrode having a strength and a shape capable of being locally pressed against a welding powder in the form of fine particles placed on a repaired portion of a metal member or a thin plate-shaped welding material applied to the repaired portion; 300 to 150 between the primary and secondary electrodes
It is composed of a power supply device that applies a large current of 0 ampere in a pulse shape within a short time of 1/1000 to 4/1000 seconds. The arc melting machine approaches a build-up weld formed on a metal member. Conductivity is imparted between the primary electrode, the secondary electrode electrically connected to the metal member, and the secondary electrode and the primary electrode that is brought close to the build-up weld portion.
A power supply device for generating an arc from the next electrode to the build-up weld for a short time at a current value within a predetermined range, and an inert gas supply for placing the build-up weld under an inert gas atmosphere before and after the arc is generated. A build-up welding device characterized by being configured with a mechanism. 3. The welding machine according to claim 2 uses a primary electrode having a built-in permanent magnet, and uses a magnetic fine particle powder in the case of overlay welding the repaired portion of the metal member with powdered welding powder. Build-up welding device, characterized in that the welding powder is attached to the outer peripheral surface of the electrode. 4. A build-up welding apparatus, wherein the welding machine according to claim 2 and the arc melting machine have an integrated structure in which respective power supply circuits are combined. 5. A build-up welding apparatus, wherein the welding machine according to claim 2 and the arc melting machine are of a separate type in which respective power supply circuits are independent.