JP2021065893A - Welding device and control method for welding device - Google Patents

Abstract

To perform spiral overlay welding on an outer peripheral surface of a heat transfer tube while appropriately satisfying welding specifications such as overlay thickness and overlay surface roughness.SOLUTION: A welding device 200 comprises: a movement mechanism which moves a heat transfer tube T along an axis X; a rotating mechanism which rotates the heat transfer tube T around the axis X; an overlay welding mechanism 20 welds while supplying a weld material onto an outer peripheral surface of the heat transfer tube T of which a position is fixed with respect to an installation surface S on which the welding device 200 is installed, as well as, which passes a prescribed welding position P0; and a control part 90 which controls the movement mechanism, the rotating mechanism, and the overlay welding mechanism 20. The control part 90 controls so that the overlay welding mechanism 20 performs spiral overlay welding on the outer peripheral surface of the heat transfer tube T in the state that the movement mechanism moves the heat transfer tube T along the axis X direction, and the rotating mechanism rotates the heat transfer tube T around the axis X.SELECTED DRAWING: Figure 4

Description

The present disclosure relates to a welding apparatus and a method for controlling the welding apparatus.

Some of the furnace walls used in boilers use heat transfer panels in which long heat transfer tubes through which water and steam flow and plate-shaped fins are alternately connected by welding. Then, in order to ensure the corrosion resistance of the heat transfer tube, it is known that spiral welding is performed on the surface of the heat transfer tube with a corrosion resistant material (see, for example, Patent Document 1 (paragraph 0072, etc.)). Patent Document 1 discloses that by feeding a TIG welding torch while rotating a raw pipe, a corrosion-resistant layer is formed by spiral welding on the entire circumference of the raw pipe.

Japanese Unexamined Patent Publication No. 2018-189282

In the spiral winding welding disclosed in Patent Document 1, since the welding torch moves with respect to the long heat transfer tube, the distance between the welding torch and the heat transfer tube can be determined at each position along the moving direction of the welding torch. Fluctuations are likely to occur. If the distance between the welding torch and the heat transfer tube or the angle between the welding torch fluctuates, it becomes impossible to accurately manage the positional relationship between the welding torch and the heat transfer tube, and at each position in the longitudinal direction of the heat transfer tube. There is a possibility that the welding condition of the torch will fluctuate, and it will not be possible to meet the welding specifications for which the allowable range such as overlay thickness and overlay surface roughness is set.

The present disclosure has been made in view of such circumstances, and spiral overlay welding is performed on the outer peripheral surface of the heat transfer tube while appropriately satisfying welding specifications such as overlay thickness and overlay surface roughness. It is an object of the present invention to provide a welding apparatus capable of being capable of and a method of controlling the welding apparatus.

The welding apparatus according to one aspect of the present disclosure includes a moving mechanism that performs overlay welding on the outer peripheral surface of a cylindrical heat transfer tube arranged along an axis and moves the heat transfer tube along the axis, and the transfer. While supplying the welding material to the outer peripheral surface of the heat transfer tube that is fixed in position with respect to the installation surface on which the welding device is installed and that passes through the predetermined welding position and the rotation mechanism that rotates the heat tube around the axis. A build-up welding mechanism for welding, a moving mechanism, a rotating mechanism, and a control unit for controlling the build-up welding mechanism are provided. In the control unit, the moving mechanism moves the heat transfer tube along the axis. The overlay welding mechanism controls the overlay welding to spirally perform overlay welding on the outer peripheral surface of the heat transfer tube while the rotating mechanism rotates the heat transfer tube around the axis.

The method for controlling the welding device according to one aspect of the present disclosure is a method for controlling a welding device that performs overlay welding on the outer peripheral surface of a cylindrical heat transfer tube arranged along an axis. A moving mechanism that moves the heat transfer tube along the axis, a rotation mechanism that rotates the heat transfer tube around the axis, and a rotation mechanism that rotates the heat transfer tube around the axis are fixed to the installation surface on which the welding device is installed and pass through a predetermined welding position. A build-up welding mechanism for welding while supplying a welding material to the outer peripheral surface of the heat transfer tube is provided, the moving mechanism moves the heat transfer tube along the axis, and the rotating mechanism moves the heat transfer tube. It is provided with a control step of controlling the welding apparatus so that the overlay welding mechanism spirally overlays welds on the outer peripheral surface of the heat transfer tube in a state of being rotated around the axis.

According to the present disclosure, a welding device and a method for controlling a welding device capable of performing spiral overlay welding on the outer peripheral surface of a heat transfer tube by appropriately satisfying welding specifications such as overlay thickness and overlay surface roughness. Can be provided.

It is a vertical sectional view of the gasification furnace provided in the gasification furnace equipment which concerns on one Embodiment of this disclosure. It is a cross-sectional view which shows the schematic structure of the gasification furnace wall shown in FIG. It is an enlarged sectional view which shows the schematic structure of the gasification furnace wall shown in FIG. It is a side view of the welding apparatus which concerns on one Embodiment of this disclosure, and shows the state which started overlay welding on the outer peripheral surface of a heat transfer tube. It is a side view of the welding apparatus which concerns on one Embodiment of this disclosure, and shows the state which overlay welding is performed on the outer peripheral surface of a heat transfer tube. It is a side view of the welding apparatus which concerns on one Embodiment of this disclosure, and shows the state which completed the overlay welding to the outer peripheral surface of a heat transfer tube. It is a partially enlarged view of the welding apparatus shown in FIG. FIG. 7 is a cross-sectional view taken along the line AA of the welding apparatus shown in FIG. 7 and shows a first lower support portion. FIG. 7 is a cross-sectional view taken along the line BB of the welding apparatus shown in FIG. 7, showing a second lower support portion and an upper support mechanism. FIG. 7 is a cross-sectional view taken along the line CC of the welding apparatus shown in FIG. 7, showing a third lower support portion. It is a figure which shows the modification of the upper support mechanism shown in FIG. It is a perspective view which shows the internal structure of the movable carriage shown in FIG. It is a schematic block diagram which shows the cooling mechanism shown in FIG. FIG. 7 is a cross-sectional view taken along the line DD of the overlay welding mechanism shown in FIG. 7, showing a state in which the measuring mechanism measures a heat transfer tube that has not been overlay welded. FIG. 7 is a cross-sectional view taken along the line DD of the overlay welding mechanism shown in FIG. 7, showing a state in which the measuring mechanism measures the overlay-welded heat transfer tube. It is a schematic block diagram which shows the control structure of the welding apparatus shown in FIG. It is a figure which shows the modification of the 2nd lower support part and the upper support mechanism shown in FIG.

Hereinafter, the welding apparatus and the control method of the welding apparatus according to the embodiment of the present disclosure will be described with reference to the drawings. In the welding apparatus of the present embodiment, when performing overlay welding, cooling water (cooling medium) is circulated inside the cylindrical heat transfer tube to cool the heat transfer tube itself and its surroundings, thereby cooling the outer periphery of the heat transfer tube. It is a device for overlay welding a welding material to improve corrosion resistance and heat resistance on the surface.
In the following description, the above and below descriptions such as above and below shall indicate the above and below in the vertical direction.

The heat transfer tube in which the welding material is built-up welded by the welding device 200 of the present embodiment is connected to, for example, a plurality of plate materials by welding to form a heat transfer panel. The heat transfer panel is arranged, for example, inside the furnace of the boiler or inside the gasification furnace. In the following, as an example in which a heat transfer panel using a heat transfer tube in which the welding material is built-up welded is arranged, the gasification furnace will be described with reference to the drawings. FIG. 1 is a vertical sectional view of a gasifier according to an embodiment of the present disclosure.

The gasification furnace 101 shown in FIG. 1 is an apparatus that mainly produces a generated gas containing hydrogen and carbon monoxide in an integrated coal gasification combined cycle (IGCC). As the fuel to be supplied to the gasification furnace 101, for example, a carbon-containing solid fuel such as coal is used, and by pulverizing with a coal mill (not shown) or the like, pulverized coal pulverized into fine particles is supplied. As a combustion method for generating flammable gas (produced gas) from fuel, an air combustion method using an oxidizing agent mainly composed of air is used. The generated gas generated by the gasification furnace 101 is supplied to the combustor of the gas turbine that rotationally drives the generator.

As shown in FIG. 1, the gasification furnace 101 is formed so as to extend in the vertical direction, and pulverized coal and oxygen are supplied to the lower side in the vertical direction, and the generated gas gasified by partial combustion is in the vertical direction. It circulates from the lower side to the upper side. The gasifier 101 has a pressure vessel 110 and a gasifier wall 111 provided inside the pressure vessel 110. As the gasification furnace wall 111, a heat transfer panel including a heat transfer tube T is used.

The gasifier 101 forms an annulus portion 115 in the space between the pressure vessel 110 and the gasifier wall 111. Further, in the space inside the gasifier wall 111, the gasifier 101 has a convertor portion 116, a diffuser portion 117, and a reducer portion 118 in this order from the lower side in the vertical direction (that is, the upstream side in the flow direction of the generated gas). Is forming.

The pressure vessel 110 is formed in a tubular shape having a hollow space inside, and a gas discharge port 121 is formed at the upper end portion, while a slug hopper 122 is formed at the lower end portion (bottom portion). The gasification furnace wall 111 is formed in a tubular shape having a hollow space inside, and the wall surface thereof is provided so as to face the inner surface of the pressure vessel 110. In the present embodiment, the pressure vessel 110 is formed in a cylindrical shape, for example, and the diffuser portion 117 of the gasification furnace wall 111 is also formed in a cylindrical shape, for example. The gasification furnace wall 111 is connected to the inner surface of the pressure vessel 110 by a support member (not shown).

The gasifier wall 111 separates the inside of the pressure vessel 110 into an internal space 154 and an external space 156. The gasification furnace wall 111 has a shape in which the cross-sectional shape changes at the diffuser portion 117 between the convertor portion 116 and the reducer portion 118. The upper end of the gasifier wall 111 on the vertically upper side is connected to the gas discharge port 121 of the pressure vessel 110, and the lower end thereof on the vertically lower side is provided with a gap from the bottom of the pressure vessel 110. ing.

The stored water is stored in the slug hopper 122 formed at the bottom of the pressure vessel 110, and the lower end of the gasification furnace wall 111 is flooded with the stored water to seal the inside and outside of the gasification furnace wall 111. ing. Burner devices 126 and 127 are inserted into the gasification furnace wall 111, and a thin gas cooler 102 is arranged in the internal space 154.

The annular portion 115 is a space formed inside the pressure vessel 110 and outside the gasification furnace wall 111, that is, an external space 156, and nitrogen, which is an inert gas separated by an air separation facility (not shown), is contained in the annulus portion 115. It is supplied through a nitrogen supply line (not shown). Therefore, the annulus portion 115 becomes a space filled with nitrogen. A pressure equalizing pipe (not shown) for equalizing the pressure inside the gasification furnace 101 is provided near the upper portion of the annulus portion 115 in the vertical direction. The pressure equalizing pipe in the furnace is provided so as to communicate the inside and outside of the gasification furnace wall 111, and the pressure between the inside (combustor part 116, diffuser part 117 and reducer part 118) and the outside (annulus part 115) of the gasification furnace wall 111. The pressure is approximately equalized so that the difference is within a predetermined pressure.

The convertor section 116 is a combustion chamber that partially burns pulverized coal and char (unreacted coal and ash) and air, and a plurality of burner devices 126 are formed on the gasification furnace wall 111 of the convertor section 116. A combustion chamber consisting of is arranged. The high-temperature combustion gas obtained by burning the pulverized coal and a part of the char in the converter section 116 passes through the diffuser section 117 and flows into the reducer section 118.

The reducer section 118 is maintained at a high temperature state required for the gasification reaction, supplies pulverized coal to the combustion gas from the convertor section 116 and partially oxidatively burns the pulverized coal to volatile components (carbon monoxide, hydrogen, lower hydrocarbons). Etc.), and the space is gasified to generate the generated gas. A combustion device composed of a plurality of burner devices 127 is arranged on the gasification furnace wall 111 of the reducer unit 118.

Next, the gasification furnace wall 111 will be described with reference to the drawings. FIG. 2 is a cross-sectional view showing a schematic configuration of the gasification furnace wall 111 shown in FIG. FIG. 3 is an enlarged cross-sectional view showing a schematic configuration of the gasification furnace wall 111 shown in FIG.

The horizontal cross-sectional shape of the gasification furnace wall 111 is a polygonal tubular shape or a cylindrical tubular shape, but the form shown in FIG. 3 is an example of a cylindrical shape, and a plurality of tubular wall portions 140 have a tubular shape. A water-cooled wall pipe 142 is provided. That is, a plurality of water-cooled wall pipes 142 are arranged concentrically on a part of the wall portion 140.

The gasifier 101 has a cooling water circulation mechanism (not shown) that circulates a refrigerant (water supply, steam, etc. as cooling water) in the water-cooled wall pipe 142. The plurality of water-cooled wall pipes 142 extend the gasifier 101 along the vertical direction over the entire area, extend vertically in the vertical direction without being partially cut, and are arranged side by side in the circumferential direction. The wall portion 140 of the gasifier 101 is formed.

As shown in FIG. 3, at least a part of the water-cooled wall tube 142 has a heat transfer tube T and a weld bead WB provided on the outer periphery of the heat transfer tube T. The heat transfer tube T is a pipeline through which cooling water flows. The weld beads WB are arranged on the entire circumference of the heat transfer tube T in the circumferential direction and cover the outer peripheral surface of the heat transfer tube T. The welding bead WB is formed by performing overlay welding on the outer peripheral surface of the heat transfer tube T by a welding device 200 described later.

The wall portion 140 is provided with a plate material (fin) 166 between the water-cooled wall pipe 142 and the water-cooled wall pipe 142. The wall portion 140 of the present embodiment has a tubular shape by arranging a plurality of water-cooled wall pipes 142 concentrically and closing the space between the water-cooled wall pipes 142 and the water-cooled wall pipes 142 with a plate material 166. Further, the wall portion 140 has a welded portion 168 that connects the weld bead WB of the water-cooled wall pipe 142 and the plate material 166. The welded portion 168 is formed at an end portion on the inner space 154 side and an end portion on the outer space 156 side of the contact portion between the weld bead WB and the plate material 166. The welded portion 168 is formed by welding and is in close contact with both the weld bead WB and the plate material 166 to connect the weld bead WB of the water-cooled wall pipe 142 and the plate material 166.

In the gasification furnace wall 111, the heat transfer tube T is made of the first material, and the weld bead WB is made of the second material. Further, the plate material 166 and the welded portion 168 may be made of a second material. The first material and the second material are metals. The second material is a material having higher corrosion resistance (corrosion resistance) and higher heat resistance than the first material. The gasification furnace wall 111 can protect the heat transfer tube T by forming the weld bead WB with a material having higher corrosion resistance and heat resistance than the heat transfer tube T.

Specifically, the internal space 154 inside the gasification furnace wall 111 through which the flammable gas flows flows as a gasified product gas obtained by partially burning the oxidant (gas containing oxygen) and the fuel, and has a high temperature. It becomes. By covering the surface of the heat transfer tube T on the internal space 154 side with the weld bead WB, the heat transfer tube T can be protected from corrosion and a high temperature usage environment. Further, slag such as coal adheres to and falls off from the heat transfer tube T, the weld bead WB, and the plate material 166 of the gasification furnace wall 111, so that the temperature of the wall surface of the gasification furnace wall 111 changes, and the heat transfer tube When a temperature distribution occurs in T or the weld bead WB, the influence of the thermal expansion difference due to the difference in the material becomes large, and the local thermal stress may become large. Therefore, the weld bead WB is formed of a material having high heat resistance. There is.

Further, in the internal space 154 of the convertor portion 116, the diffuser portion 117, and the reducer portion 118 of the gasification furnace wall 111, the temperature difference tends to be large due to the high temperature atmosphere exceeding 1500 ° C. Therefore, in the present embodiment, the outer space 156 side and the inner space 154 side of the gasifier wall 111 have the same shape symmetrical with respect to the surface connecting the axis of the heat transfer tube T and the plate thickness center of the plate material 166. Even if a local temperature distribution occurs, it is possible to suppress an increase in heat load due to a difference in thermal expansion, and it is possible to improve the durability of the gasification furnace wall 111.

Next, a welding device 200 that spirally overlays welds the outer peripheral surface of the heat transfer tube T will be described with reference to the drawings. FIG. 4 is a side view of the welding apparatus 200 according to the embodiment of the present disclosure, showing a state in which overlay welding is started on the outer peripheral surface of the heat transfer tube T and the welding bead WB is started to be formed. FIG. 5 is a side view of the welding apparatus 200 according to the embodiment of the present disclosure, showing a state in which a weld bead WB is formed by overlay welding the outer peripheral surface of the heat transfer tube T. FIG. 6 is a side view of the welding apparatus 200 according to the embodiment of the present disclosure, showing a state in which overlay welding to the outer peripheral surface of the heat transfer tube T is completed.

FIG. 7 is a partially enlarged view of the welding apparatus 200 shown in FIG. FIG. 8 is a cross-sectional view taken along the line AA of the welding apparatus 200 shown in FIG. 7, showing the first lower support portion 31. FIG. 9 is a cross-sectional view taken along the line BB of the welding apparatus 200 shown in FIG. 7, showing a second lower support portion 32 and an upper support mechanism 40. FIG. 10 is a cross-sectional view taken along the line CC of the welding apparatus 200 shown in FIG. 7, showing a third lower support portion 33. FIG. 11 is a diagram showing a modified example of the upper support mechanism 40 shown in FIG. FIG. 12 is a perspective view showing the internal structure of the movable carriage 10 shown in FIG.

In the welding apparatus 200 shown in FIGS. 4 to 6, the welding material is spirally overlaid on the outer peripheral surface of the heat transfer tube T with respect to the water-cooled wall tube 142 of the gasification furnace wall 111 to form a welding bead WB. It is a device to weld. As shown in FIGS. 4 to 6, the heat transfer tube T is a cylindrical tube body arranged along the axis X extending in the horizontal direction of the paper surface. As shown in FIGS. 4 to 6, the welding apparatus 200 includes a movable carriage 10, an overlay welding mechanism 20, a lower support mechanism 30, an upper support mechanism 40, a cooling mechanism 50, a measurement mechanism 60, and a main body. A unit 70, an imaging unit 80, a display unit 85, and a control unit 90 are provided.

In the welding device 200, the heat transfer tube T is arranged at a constant height from the installation surface S so as to be parallel to the installation surface S, and is supported by the lower support mechanism 30 and the upper support mechanism 40. The welding device 200 rotates the heat transfer tube T around the axis X at a predetermined rotation speed while moving the heat transfer tube T along the moving direction MD at a predetermined speed by the movable carriage 10. The welding device 200 is built-up welding mechanism 20 installed at a position fixed above the paper surface with respect to the installation surface S with respect to the heat transfer tube T rotating around the axis X while moving along the moving direction MD. Perform build-up welding.

Overlay welding is started on the outer peripheral surface of the heat transfer tube T in the state shown in FIG. 4, the range of the weld bead WB formed in a spiral shape increases as shown in FIG. 5, and the heat transfer tube T is in the state shown in FIG. Overlay welding to the outer peripheral surface of the is completed. By executing the operations of FIGS. 4 to 6, the welding apparatus 200 forms a weld bead WB in which the welding material is spirally overlaid on the outer peripheral surface of the heat transfer tube T.

The movable carriage 10 is an example of a mechanism that rotates the heat transfer tube T at a predetermined speed while moving it along the axis X at a predetermined speed. As shown in FIG. 12, the movable carriage 10 includes a moving mechanism 11 for moving the heat transfer tube T along the axis X, and a rotating mechanism 12 for rotating the heat transfer tube T around the axis X.

As shown in FIG. 12, the moving mechanism 11 drives the moving motor 11a to rotate the first gear 11c connected to the drive shaft 11b in the coaxial direction with the drive shaft 11b, and engages with the first gear 11c. The combined second gear 11d is rotated. The second gear 11d rotates the third gear 11f connected via the connecting shaft 11e. The third gear 11f is engaged with a rack gear 71 provided on the main body 70 fixed to the installation surface S on which the welding device 200 is installed. Therefore, as the third gear 11f rotates, the carriage portion 11g of the moving mechanism 11 moves along the rail 72 of the main body portion 70 in the moving direction MD. Here, the moving direction MD is a direction parallel to the axis X direction of the heat transfer tube T.

The heat transfer tube T is held by the fixing portion 12e on the outer peripheral surface of the heat transfer tube T so as not to move in the axis X direction with respect to the moving mechanism 11 in a state where the movable carriage 10 can rotate around the axis X by the rotating mechanism 12. And fixed. Therefore, when the moving mechanism 11 moves along the axis X, the heat transfer tube T also moves along the axis X accordingly. In this way, the moving mechanism 11 moves the heat transfer tube T along the axis X by rotating the moving motor 11a. The drive of the moving motor 11a is controlled by a control signal transmitted from the control unit 90.

As shown in FIG. 12, the rotation mechanism 12 drives the rotation motor 12a to rotate the first gear 12c connected to the drive shaft 12b, and causes the second gear 12d engaged with the first gear 12c. Rotate. The second gear 12d is connected so as to be integrated with a fixing portion 12e that holds the outer peripheral surface of the heat transfer tube T and is fixed to the second gear 12d so as not to rotate. Therefore, when the second gear 12d rotates, the heat transfer tube T also rotates around the axis X accordingly.

In this way, the rotation mechanism 12 rotates the rotation motor 12a to rotate the heat transfer tube T around the axis X in a fixed direction at a predetermined rotation speed. The drive of the rotary motor 12a is controlled by a control signal transmitted from the control unit 90.

As shown in FIG. 7, the overlay welding mechanism 20 is a device that spirally forms a welding bead WB while supplying a welding material to the outer peripheral surface of a heat transfer tube T passing through a predetermined welding position P0 on the axis X. is there. The overlay welding mechanism 20 is fixed to the installation surface S on which the welding device 200 is installed via the main body 70. The overlay welding mechanism 20 performs TIG (Tungsten Inert Gas) welding by, for example, a welding torch 21 having a tungsten electrode 21a. The overlay welding mechanism 20 applies a voltage to the tungsten electrode 21a by a control signal transmitted from the control unit 90 to supply an electric current, thereby welding between the tip of the tungsten electrode 21a and the outer peripheral surface of the heat transfer tube T. An electric current flows to form an arc and the temperature rises.

A welding wire (welding material) is supplied to the arc formed by the welding torch 21. A predetermined feed amount is supplied to the welding wire by a control signal transmitted from the control unit 90, and the welding wire is heated by Joule heat by passing an electric current through the welding wire. As the welding wire of the present embodiment, for example, a corrosion-resistant material containing a solid solution reinforced nickel-based alloy such as Inconel (registered trademark) or a high chromium-containing alloy can be used.

The overlay welding mechanism 20 is fixed to the main body 70, but the heat transfer tube T moves along the moving direction MD and rotates around the axis X. Therefore, the overlay welding mechanism 20 spirally overlays the corrosion-resistant material on the outer peripheral surface of the heat transfer tube T by welding the heat transfer tube T at a fixed position of the main body 70. .. Further, since the overlay welding mechanism 20 is at a fixed position of the main body 70, the positional relationship between the welding torch 21 and the heat transfer tube T can be managed with high accuracy.

The lower support mechanism 30 is a mechanism that supports the heat transfer tube T from below, and is fixed to the installation surface S. The lower support mechanism 30 includes a first lower support portion 31, a second lower support portion 32, and a third lower support portion 33. Hereinafter, the lower support mechanism 30 will be described with reference to the drawings. FIG. 8 is a cross-sectional view taken along the line AA of the welding apparatus 200 shown in FIG. 7, showing the first lower support portion 31. FIG. 9 is a cross-sectional view taken along the line BB of the welding apparatus 200 shown in FIG. 7, showing a second lower support portion 32 and an upper support mechanism 40. FIG. 10 is a cross-sectional view taken along the line CC of the welding apparatus 200 shown in FIG. 7, showing a third lower support portion 33.

The first lower support portion 31 supports the lower part of the heat transfer tube T at the position closest to the overlay welding mechanism 20, and is fixed to the main body portion 70 to which the overlay welding mechanism 20 is fixed. As shown in FIG. 8, the first lower support portion 31 is a pair of spheres (first spheres) 31a that come into contact with two points in the circumferential direction of the outer peripheral surface on the lower side of the heat transfer tube T, and a pair of spheres 31a, respectively. Has a holding portion (first holding portion) 31b, which rotatably holds the ball in an arbitrary direction. The first lower support portion 31 is supported by a pair of spheres 31a in a state where the lower part of the heat transfer tube T is sandwiched from two different positions in the circumferential direction, thereby supporting the center position of the heat transfer tube T (position of the axis X). ) Can be held in a fixed position.

The second lower support portion 32 is arranged adjacent to the first lower support portion 31, and is arranged on the upstream side (right side of the paper surface) of the moving direction MD of the heat transfer tube T along the axis X from the first lower support portion 31. Has been done. As shown in FIG. 9, the second lower support portion 32 is a pair of spheres (first spheres) 32a that come into contact with two points in the circumferential direction of the outer peripheral surface on the lower side of the heat transfer tube T, and a pair of spheres 32a, respectively. Has a holding portion (first holding portion) 32b, which rotatably holds the ball in an arbitrary direction. The second lower support portion 32 is supported by a pair of spheres 32a while sandwiching the lower part of the heat transfer tube T from two different positions in the circumferential direction, thereby supporting the center position of the heat transfer tube T (position of the axis X). ) Can be held in a fixed position.

The third lower support portion 33 has a plurality of locations on the downstream side (left side of the paper surface) of the heat transfer tube T in the moving direction MD with respect to the first lower support portion 31, and the heat transfer tube T moves with respect to the second lower support portion 32. It is arranged at a plurality of locations on the upstream side (right side of the paper) of the direction MD. As shown in FIG. 10, the third lower support portion 33 is located on the lower outer peripheral surface of the heat transfer tube T or on the lower outer surface of the heat transfer tube T in a state where a weld bead WB is formed (water-cooled wall tube 142). It has a pair of spheres (first spheres) 33a that come into contact with two points in the circumferential direction of the outer peripheral surface, and a holding portion (first holding portion) 33b that rotatably holds each of the pair of spheres 33a in an arbitrary direction. .. The third lower support portion 33 is supported by a pair of spheres 33a in a state of sandwiching the lower part of the heat transfer tube T from two different positions in the circumferential direction, thereby supporting the center position of the heat transfer tube T (position of the axis X). ) Can be held in a fixed position.

The third lower support portion 33 includes a height adjusting mechanism (switching mechanism) 33c capable of adjusting the distance in the direction orthogonal to the installation surface S at the tip position supporting the heat transfer tube T (vertical direction on the paper surface). The height adjusting mechanism 33c has a supported state in which the sphere 33a is held at a position supporting the heat transfer tube T (state shown in FIG. 6) and a retracted state in which the sphere 33a is retracted to a position not supporting the heat transfer tube T (FIG. 4). And the state shown in FIG. 5) is a mechanism that can be switched. The height adjusting mechanism 33c is a mechanism for moving the tip position of the sphere 33a along a direction orthogonal to the installation surface S (vertical direction on the paper surface). The height adjusting mechanism 33c is, for example, a mechanism that expands and contracts vertically in the vertical direction by the pressure of compressed air supplied from a compressed air source (not shown), and manages the tip position of the sphere 33a with a stopper (not shown). ..

Among the third lower support portions 33, those arranged at a plurality of locations on the downstream side of the moving direction MD of the heat transfer tube T with respect to the first lower supporting portion 31 come into contact with each other when the movable carriage 10 moves in the moving direction MD. The height adjusting mechanism 33c moves the tip position of the sphere 33a downward so as to prevent the sphere 33a from being retracted. In the state shown in FIGS. 4 and 5, the third lower support portion 33 arranged on the most downstream side of the moving direction MD of the heat transfer tube T does not pass through the movable carriage 10, so that the third lower support portion 33 does not come into contact with the movable carriage 10. In order to avoid this, the tip position of the sphere 33a is in the retracted state. On the other hand, in the state shown in FIG. 6, since the movable carriage 10 has passed, the tip position of the sphere 33a is in the supporting state.

Among the third lower support portions 33, those arranged at a plurality of locations on the upstream side of the moving direction MD of the heat transfer tube T with respect to the first lower support portion 31 are height adjusting mechanisms so as not to come into contact with the cooling mechanism 50. The tip position of the sphere 33a is moved downward by the 33c so as to be in the retracted state. In the state shown in FIG. 4, the third lower support portion 33 arranged on the most upstream side of the moving direction MD of the heat transfer tube T does not pass through the cooling mechanism 50, so that the tip position of the sphere 33a is in the support state. .. On the other hand, in the states shown in FIGS. 5 and 6, since the cooling mechanism 50 has passed through, the tip position of the sphere 33a is in the retracted state in order to avoid contact with the cooling mechanism 50.

The upper support mechanism 40 is a mechanism that supports the heat transfer tube T from above, and is fixed to the main body 70 to which the overlay welding mechanism 20 is fixed. The upper support mechanism 40 welds the overlay welding mechanism 20 by supporting the heat transfer tube T on the upstream side of the moving direction MD of the heat transfer tube T and closer to the overlay welding mechanism 20 than the overlay welding mechanism 20. It suppresses fluctuations in the positional relationship between the welding torch 21 and the heat transfer tube T, such as the distance from the torch 21 to the heat transfer tube T and the angle with the welding torch 21.

Here, the upper support mechanism 40 is fixed to the main body 70, but other embodiments may be used. For example, the upper support mechanism 40 is not fixed to the main body 70, but is a support mechanism provided directly on the installation surface S (for example, a pair of supports extending upward from the side of the second lower support 32). It may be directly supported with respect to the installation surface S by a gate-shaped mechanism (a gate-shaped mechanism having a column and a beam for horizontally connecting a pair of support columns).

As shown in FIGS. 7 and 9, the upper support mechanism 40 rotatably holds each of the sphere (second sphere) 40a in contact with the outer peripheral surface on the upper side of the heat transfer tube T and the sphere 40a in an arbitrary direction. It has a holding portion (second holding portion) 40b and a height adjusting mechanism 40c. The height adjusting mechanism 40c is a mechanism capable of adjusting the distance in the orthogonal direction (vertical direction on the paper surface) with respect to the installation surface S at the tip position supporting the heat transfer tube T.

The height adjusting mechanism 40c has a support state in which the sphere 40a is held at a position supporting the heat transfer tube T (state shown by a broken line in FIG. 9) and a retracted state in which the sphere 40a is retracted to a position not supporting the heat transfer tube T (a state shown by a broken line in FIG. 9). It is a mechanism that can switch between the state shown by the solid line in FIG. 9). The height adjusting mechanism 40c is a mechanism for moving the tip position of the sphere 33a along a direction orthogonal to the installation surface S (vertical direction on the paper surface). The height adjusting mechanism 40c is, for example, a mechanism that expands and contracts in the vertical direction by the pressure of compressed air supplied from a compressed air source (not shown). After the heat transfer tube T is supported by the lower support mechanism 30, the height adjusting mechanism 40c switches the position of the sphere 40a from the retracted state to the supported state by the control signal transmitted from the control unit 90. Further, when the tip position of the sphere 40a is in the supported state, the pressure of the compressed air supplied from the supported state compressed air source (not shown) may hold the sphere 40a while maintaining elasticity from the upper side to the lower side. ..

Next, with reference to FIG. 7, the positional relationship between the overlay welding mechanism 20, the lower support mechanism 30, and the upper support mechanism 40 will be described. In FIG. 7, the position (welding position) on the axis X where the welding torch 21 of the overlay welding mechanism 20 performs overlay welding on the outer peripheral surface of the heat transfer tube T is defined as P0. Further, the position on the axis X where the sphere 31a of the first lower support portion 31 of the lower support mechanism 30 supports the outer peripheral surface on the lower side of the heat transfer tube T in which overlay welding is not performed is defined as P1.

Further, of the third lower support portion 33 of the lower support mechanism 30, the sphere 33a, which is arranged adjacent to the downstream side of the first lower support portion 31 in the moving direction MD, is the heat transfer tube T to which overlay welding has been performed. Let P2 be the position on the axis X that supports the outer peripheral surface on the lower side of. Further, the position on the axis X where the sphere 32a of the second lower support portion 32 of the lower support mechanism 30 supports the outer peripheral surface on the lower side of the heat transfer tube T in which overlay welding is not performed is defined as P3.

In FIG. 7, the axis Y0 is an axis that passes through P0 and extends in the vertical direction, and the axis Y1 is an axis that passes through P1 and extends in the vertical direction. Further, the axis Y2 is an axis that passes through P2 and extends in the vertical direction, and the axis Y3 is an axis that passes through P3 and extends in the vertical direction.

The distance from P0 to P1 in the axis X direction (first distance) is L1, the distance from P0 to P2 in the axis X direction (second distance) is L2, and the distance from P1 to P3 in the axis X direction. Is L3. Further, the distance between the position on the axis X where the sphere 40a of the upper support mechanism 40 supports the outer peripheral surface on the upper side of the heat transfer tube T not overlaid welded and the axis X direction to P0 is L4. .. Here, L1, L2, L3, and L4 satisfy the relationship of the following equation (1).
L1 <L3 <L4 <L2 (1)

As shown in the formula (1), the distance L1 in the axis X direction from P0 to P1 is shorter than the distance L2 in the axis X direction from P0 to P2. Therefore, the first lower support portion 31 arranged on the upstream side of the moving direction MD of the heat transfer tube T from P0 is a welding position of the third lower supporting portion 33 arranged on the downstream side of the moving direction MD P0. The heat transfer tube T is supported from below at a position P1 close to. Further, the second lower support portion 32 arranged on the upstream side of the moving direction MD of the heat transfer tube T from P0 is at a position P3 slightly separated from P0, which is a welding position, on the upstream side of the first lower support portion 31. The heat transfer tube T is supported from below. On the other hand, the third lower support portion 33 arranged on the downstream side of the moving direction MD of the heat transfer tube T from P0 is transmitted at a position P2 separated from P0, which is a welding position, on the downstream side of the first lower support portion 31. A state in which a weld bead WB is formed on the outer peripheral surface of the heat tube T (water-cooled wall tube 142) is supported from below.

Since the welding bead WB does not exist on the upstream side of the MD in the moving direction from P0, the outer peripheral surface of the heat transfer tube T in which welding is not performed is supported by P1 in the vicinity of the welding position P0 and P3 in the vicinity, and the overlay welding mechanism is used. It is possible to suppress fluctuations in the positional relationship between the welding torch 21 and the outer peripheral surface of the heat transfer tube T, such as the distance from the welding torch 21 of 20 to the heat transfer tube T and the angle with the welding torch 21. Further, on the downstream side of the moving direction MD, overlay welding is performed to form a weld bead WB, and the outer peripheral surface in a state where the surface has an uneven shape is supported at a position P2 away from the welding position P0, and the uneven shape is formed. It is possible to suppress the vibration when passing through the third lower support portion 33 from being transmitted to the overlay welding mechanism 20, and to suppress the influence of a minute positional change of the axis X due to the wall thickness of the weld bead WB.

L1 is set to, for example, 10 mm or more and 100 mm or less. The reason why L1 is set to 10 mm or more is to prevent the high temperature weld bead WB on which overlay welding is performed at P0 from coming into contact with the first lower support portion 31. Further, L1 is set to 100 mm or less because the heat transfer tube T is supported at a position close to P0 so that the distance from the tip of the welding torch 21 at P0 to the outer peripheral surface of the heat transfer tube T and the welding torch 21 This is to suppress the fluctuation of the angle of.

L2 is set to, for example, 1000 mm or more and 2500 mm or less. L2 is set to 1000 mm or more because the vibration when the uneven shape of the weld bead WB formed on the outer peripheral surface of the heat transfer tube T passes through the third lower support portion 33 is transmitted to the build-up welding mechanism 20. This is to suppress this and to suppress the influence of minute positional fluctuations of the axis X due to the wall thickness distribution of the weld bead WB. Further, the reason why L2 is set to 2500 mm or less is that if the distance from P0 to P2 is too long, the heat transfer tube T is partially bent, and the heat transfer tube T cannot be stably supported. Because.

As shown in the formula (1), the distance L3 from P1 to P3 in the axial direction X direction and the distance L4 from P0 to P3 are longer than L1 and shorter than L2, respectively. Since the second lower support portion 32 and the upper support mechanism 40 are arranged on the upstream side of the MD in the moving direction from P0, respectively, there is no uneven shape of the welding bead WB. The effect on the mechanism 20 is small. Further, by supporting the heat transfer tube T at a position closer to the welding position than the third lower support portion 33, the distance from the tip of the welding torch 21 to the outer peripheral surface of the heat transfer tube T and the angle with the welding torch 21 fluctuate. Can be suppressed.

L3 is set to, for example, 100 mm or more and 500 mm or less. It is desirable that L4 is set to, for example, about 300 mm and is set so as to match the sum of L1 and L3. By matching L4 with the sum of L1 and L3, the position on the axis X where the second lower support portion 32 supports the heat transfer tube T and the position on the axis X where the upper support mechanism 40 supports the heat transfer tube T are aligned. Match. By doing so, the heat transfer tube T can be reliably supported from above and below at the same position on the axis X.

The cooling mechanism 50 causes cooling water (cooling medium) to flow into the heat transfer tube T from the upstream end Tu of the heat transfer tube T in the moving direction MD, and cool water from the downstream end Td of the heat transfer tube T in the moving direction MD. Is a mechanism for cooling the heat transfer tube T from the inside by causing the heat transfer tube T to flow out from the inside. As shown in FIG. 13, the cooling mechanism 50 includes an inflow side pipe 51, an outflow side pipe 52, a cooling unit 53, a flow meter 54, an inflow side coupling 55, and an outflow side coupling 56. .. Here, as the cooling medium, in addition to water, a liquid such as a heat medium or mechanical hydraulic oil or a gas such as nitrogen may be used.

The cooling mechanism 50 causes the cooling water cooled by the cooling unit 53 to exchange heat with another cooling medium to flow into the upstream end Tu of the heat transfer tube T via the inflow side pipe 51. The inflow side pipe 51 and the upstream end portion Tu of the heat transfer pipe T are detachably connected by an inflow side coupling 55. The cooling water that has flowed into the heat transfer tube T flows along the moving direction MD of the heat transfer tube T, passes through P0, which is the position to be welded by the overlay welding mechanism 20, and reaches the downstream end Td of the heat transfer tube T. Be guided.

The cooling water whose temperature has risen near P0, which is the welding position, is guided to the downstream end Td of the heat transfer tube T, flows out to the outflow side pipe 52, and is guided to the cooling unit 53. The outflow side pipe 52 and the downstream end portion Td of the heat transfer tube T are detachably connected by an outflow side coupling 56. In this way, after the cooling water is discharged from the cooling unit 53, the cooling water flows in the order of the inflow side pipe 51, the heat transfer pipe T, and the outflow side pipe 52, and then returns to the cooling unit 53 to circulate.

The cooling mechanism 50 circulates cooling water from the upstream end Tu to the downstream end Td along the moving direction MD of the heat transfer tube T. The region from the upstream end Tu to P0 of the heat transfer tube T is a region where the weld bead WB is not formed. Therefore, the cooling water cooled by the cooling unit 53 is supplied to the vicinity of P0, which has the highest temperature in the heat transfer tube T, in a state where the temperature is not raised by being heated, and the heat transfer tube T in the vicinity of P0 is appropriately efficient. Can be cooled. As a result, when the weld bead WB of the heat transfer tube T is formed, it is possible to suppress a change in the amount of penetration due to the heat effect and warpage deformation of the heat transfer tube T due to thermal stress.

The cooling mechanism 50 transmits the flow rate of the cooling water measured by the flow meter 54 to the control unit 90. The control unit 90 transmits a control signal for controlling the cooling unit 53 to the cooling unit 53 so that the flow rate measured by the flow meter 54 is maintained within a predetermined flow rate range. The cooling unit 53 controls the flow rate of the cooling water discharged to the inflow side pipe 51 according to the control signal transmitted from the control unit 90. Further, a thermometer (not shown) may be provided near the cooling water flow meter 54 to control whether the temperature is within a predetermined range in addition to the cooling water flow rate.

When the flow rate of the cooling water measured by the flow meter 54 is less than a predetermined lower limit value, the control unit 90 determines that the heat transfer tube T is not properly cooled by the cooling water, and transfers the heat transfer tube T by the overlay welding mechanism 20. The overlay welding mechanism 20 is controlled so as to suspend the welding of the heat pipe T.

The measurement mechanism 60 is a mechanism that is arranged at the measurement position Pm on the downstream side of the movement direction MD from P0 where the overlay welding mechanism 20 is arranged. The measuring mechanism 60 is a mechanism for measuring the outer diameter Do of the heat transfer tube T passing through the measuring position Pm by using, for example, a non-contact type sensor. As shown in FIGS. 14 and 15, the measuring mechanism 60 includes, for example, an upper light emitting unit 61, an upper light receiving unit 62, a lower light emitting unit 63, and a lower light receiving unit 64.

For example, the upper light emitting unit 61 has a plurality of light emitting elements arranged along the vertical direction parallel to the axis Ym, and each light emitting element irradiates light toward the upper light receiving unit 62 along the horizontal direction. .. The upper light receiving unit 62 has a plurality of light receiving elements arranged along the vertical direction parallel to the axis Ym, and each light receiving element receives light emitted from the plurality of light emitting elements of the upper light emitting unit 61. ..

For example, the lower light emitting unit 63 has a plurality of light emitting elements arranged along the vertical direction parallel to the axis Ym, and each light emitting element irradiates light toward the lower light receiving unit 64 along the horizontal direction. .. The lower light receiving unit 64 has a plurality of light receiving elements arranged along the vertical direction parallel to the axis Ym, and each light receiving element receives light emitted from the plurality of light emitting elements of the lower light emitting unit 63. ..

In the measuring mechanism 60, the position of the light receiving element on the lowermost end side where the upper light receiving unit 62 receives the irradiation light from the upper light emitting unit 61 and the lower light receiving unit 64 receive the irradiation light from the lower light emitting unit 63. The outer diameter Do of the heat transfer tube T is measured in a non-contact state based on the position of the light receiving element on the uppermost end side. The outer diameter Do of the heat transfer tube T measured by the measuring mechanism 60 is transmitted to the control unit 90. The control unit 90 allows the operator to visually recognize the outer diameter Do of the heat transfer tube T measured by the measuring mechanism 60, for example, and monitor the build-up thickness of the weld bead WB of the heat transfer tube T. It may be displayed in.

FIG. 14 is a diagram showing a state in which the measuring mechanism 60 measures the heat transfer tube T that has not been overlaid welded. On the other hand, FIG. 15 is a diagram showing a state in which the welding bead WB measures the heat transfer tube T overlaid-welded by the measuring mechanism 60. As shown in FIG. 14, the outer diameter Do2 of the heat transfer tube T to which the weld bead WB is overlaid is larger than the outer diameter Do1 of the heat transfer tube T to which the weld bead WB is not overlaid welded. The overlay thickness of the weld bead WB is (Do2-Do1) / 2.

The control unit 90 fills the weld bead WB based on the outer diameter Do1 of the heat transfer tube T that has not been overlaid welded and the outer diameter Do2 of the heat transfer tube T that has been overlaid welded, which is transmitted from the measuring mechanism 60. It is possible to judge whether or not the thickness is appropriate. When, for example, the control unit 90 determines that the thickness is out of the target range of the build-up thickness of the weld bead WB and is not an appropriate thickness, for example, information indicating that the build-up thickness is not an appropriate thickness is displayed on the display unit 85. Display it.

Further, the control unit 90 may control the overlay welding mechanism 20 so as to temporarily stop the overlay welding of the heat transfer tube T by the overlay welding mechanism 20. At this time, the control unit 90 displays information on the difference between the various overlay welding conditions of the heat transfer tube T by the overlay welding mechanism 20 and the set value on the display unit 85, and the overlay thickness is an appropriate thickness. It may be possible to make it easier to determine the factors that deviate from the above.

The main body 70 is a housing fixed to the installation surface S on which the welding device 200 is installed. The overlay welding mechanism 20, the first lower support portion 31, and the upper support mechanism 40 are fixed to the main body portion 70. Further, the main body 70 includes the rack gear 71 and the rail 72 shown in FIG. 12, and the movable carriage 10 can reciprocate in the moving direction MD parallel to the axis X direction along the rail 72.

As shown in FIG. 7, for example, the imaging unit 80 is an imaging device that images the vicinity of the welding position including the tip of the tungsten electrode 21a provided at the tip of the welding torch 21 and the outer peripheral surface of the heat transfer tube T. The imaging unit 80 can output an image in the vicinity of the imaged welding position to the display unit 85. The operator who operates the welding apparatus 200 visually confirms whether or not there is any abnormality in the welding bead WB formed on the heat transfer tube T by the overlay welding mechanism 20 by visually observing the image displayed on the display unit 85. Can be done. The image in the vicinity of the welding position may be easily monitored for abnormalities in the formation of the welding bead WB by adjusting the contrast and each output intensity of RGB. When the operator determines that the welding bead WB has an abnormality, the operator suspends the operation of the welding device 200. Further, in determining the presence or absence of abnormality in the welding bead WB, the control unit 90 analyzes the image captured by the imaging unit 80, and if it is determined that there is an abnormality, the welding device 200 automatically receives a signal from the control unit 90. The operation of may be suspended.

As shown in the control configuration diagram of FIG. 16, the control unit 90 is a device that controls each part of the welding device 200 including the moving mechanism 11, the rotating mechanism 12, and the overlay welding mechanism 20. In the control unit 90, the moving mechanism 11 moves the heat transfer tube T along the axis X in the moving direction MD at a predetermined constant moving speed, and the rotating mechanism 12 rotates the heat transfer tube T around the axis X at a predetermined constant speed. The overlay welding mechanism 20 controls the overlay welding to be spirally performed on the outer peripheral surface of the heat transfer tube T in a state of being rotated at a high speed.

The control unit 90 is composed of, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a computer-readable storage medium, and the like. Then, as an example, a series of processes for realizing various functions are stored in a storage medium or the like in the form of a program, and the CPU reads this program into a RAM or the like to execute information processing / arithmetic processing. As a result, various functions are realized.

In this embodiment, the heat transfer tube T is made of, for example, low alloy steel. The outer diameter Do of the unwelded heat transfer tube T is, for example, 30 mm or more and 50 mm or less. The length of the heat transfer tube T along the axis X is, for example, 2000 mm or more and 8000 mm or less. The welding apparatus 200 performs welding by the overlay welding mechanism 20 so that the overlay thickness of the weld bead WB formed on the outer peripheral surface of the heat transfer tube T is, for example, 1 mm or more and 2.5 mm or less. The overlay thickness of the weld bead WB is set so as to be able to protect the heat transfer tube T from, for example, corrosion resistance and heat resistance.

In the control unit 90, a predetermined moving speed of the heat transfer tube T in the axial X direction by the moving mechanism 11 is set by the moving mechanism 11 so that the overlay thickness of the weld bead WB is 1 mm or more and 2.5 mm or less, and the rotation mechanism 12 A predetermined rotation speed of the heat transfer tube T around the axis X is set. Based on the measured value transmitted from the measuring mechanism 60, the heat transfer tube T so that the outer diameter Do2 and / or the build-up thickness of the weld bead WB of the overlaid welded heat transfer tube T is within the target specifications. The moving speed of the heat transfer tube T around the axis X and the rotation speed of the heat transfer tube T around the axis X may be controlled within a predetermined range. The control unit 90 controls the moving mechanism 11 so that the moving speed (feeding speed) of the heat transfer tube T in the axis X direction is, for example, 20 mm / min or more and 50 mm / min or less. Further, the control unit 90 controls the rotation mechanism 12 so that the rotation speed of the heat transfer tube T around the axis X is, for example, 5 rpm or more and 10 rpm or less.

[Other Embodiments]
In the above description, the welding apparatus 200 is provided with a single overlay welding mechanism 20 for spiral overlay welding to a single heat transfer tube T, but other embodiments may be used. For example, the welding apparatus 200 may include a plurality of overlay welding mechanisms 20 for spiral overlay welding to two or more heat transfer tubes T.

In this case, the welding device 200 includes a movable carriage 10, an overlay welding mechanism 20, a lower support mechanism 30, an upper support mechanism 40, a cooling mechanism 50, and a measurement mechanism 60 with respect to a single main body 70. The imaging unit 80 and the display unit 85 are provided adjacent to each other in the horizontal direction orthogonal to the axis X direction so that the axis X direction of the heat transfer tube T is substantially parallel to each other. In this case, a plurality of control units 90 may be provided, or a single control unit 90 may control all of them.

Further, the welding apparatus 200 is provided in a state where the longitudinal directions of the plurality of heat transfer tubes T are matched so that the operator can simultaneously confirm the welding state of the plurality of overlay welding mechanisms 20 between the adjacent heat transfer tubes T. The heat transfer tubes T may be adjacent to each other and the heat transfer tubes T may be arranged symmetrically with respect to the worker. For example, when four heat transfer tubes T are arranged in a state where the longitudinal directions are matched, two heat transfer tubes T are arranged symmetrically with respect to the worker in a direction orthogonal to the axis X direction of the heat transfer tube T. May be good. By doing so, the number of workers can be reduced because the workers can simultaneously check the welded state of the plurality of heat transfer tubes T arranged symmetrically.

Further, when the welding apparatus 200 is provided with a plurality of overlay welding mechanisms 20 for spirally overlay welding to two or more heat transfer tubes T, the welding state by each overlay welding mechanism 20 is imaged. A plurality of display units 85 for displaying the images captured by the unit 80 may be arranged so that one worker can visually recognize them at the same time. By doing so, the number of heat transfer tubes T that can be monitored by each worker increases, so that productivity can be improved.

Further, the second lower support portion 32 and the upper support mechanism 40 shown in FIG. 9 may be modified as shown in FIG. As shown in FIG. 17, the second lower support portion 32 is a pair of spheres (first spheres) 32a that come into contact with two points in the circumferential direction of the outer peripheral surface on the lower side of the heat transfer tube T, and a pair of spheres 32a, respectively. Has a holding portion (first holding portion) 32b, which rotatably holds the ball in an arbitrary direction.

The second lower support portion 32 is supported by a pair of spheres 32a while sandwiching the lower part of the heat transfer tube T from two different positions in the circumferential direction, thereby supporting the center position of the heat transfer tube T (position of the axis X). ) Can be held in a fixed position. Further, the upper support mechanism 40 is a holding portion (second holding portion) that rotatably holds each of the sphere (second sphere) 40a in contact with the outer peripheral surface on the upper side of the heat transfer tube T and the sphere 40a in an arbitrary direction. It has 40b and.

The welding apparatus described in each of the above-described embodiments is grasped as follows, for example.
The welding apparatus (200) according to the present disclosure performs overlay welding on the outer peripheral surface of a cylindrical heat transfer tube (T) arranged along the axis (X), and attaches the heat transfer tube (T) to the axis (X). ), A rotating mechanism (12) that rotates the heat transfer tube (T) around the axis (X), and an installation surface (S) on which the welding device (200) is installed. ), And the overlay welding mechanism (20) that welds while supplying the welding material to the outer peripheral surface of the heat transfer tube (T) that passes through the predetermined welding position (P0), and the moving mechanism. A control unit (90) for controlling (11), the rotation mechanism (12), and the overlay welding mechanism (20) is provided, and the control unit (90) is transmitted by the moving mechanism (11). The build-up welding mechanism (20) in a state where the heat tube (T) is moved along the axis (X) and the rotation mechanism (12) rotates the heat transfer tube (T) around the axis (X). ) Is controlled so that overlay welding is performed spirally on the outer peripheral surface of the heat transfer tube (T).

According to the welding apparatus according to the present disclosure, since the overlay welding mechanism is fixed to the installation surface on which the welding apparatus is installed, a predetermined welding position with respect to the installation surface is fixed. Therefore, fluctuations in the positional relationship between the welding torch and the heat transfer tube T, such as the distance from the welding torch of the overlay welding mechanism to the outer peripheral surface of the heat transfer tube and the angle with the welding torch, are suppressed, and at each position in the longitudinal direction of the heat transfer tube. Fluctuations in the welded state are suppressed. As a result, it becomes possible to appropriately satisfy the welding specifications such as the overlay thickness and the overlay surface roughness, and to perform the spiral overlay welding on the outer peripheral surface of the heat transfer tube.

The welding apparatus according to the present disclosure includes a lower support mechanism that supports the heat transfer tube from the vertically lower side, and the lower support mechanism is a pair of first spheres that come into contact with two points in the circumferential direction of the outer peripheral surface of the heat transfer tube. And a first holding portion that rotatably holds the first sphere in an arbitrary direction.
According to the welding apparatus according to the present disclosure, the lower side of the heat transfer tube can be stably supported at two points in the circumferential direction of the outer peripheral surface by the pair of first spheres provided in the lower support mechanism. Further, since the pair of first spheres can rotate in an arbitrary direction, the heat transfer tube that moves along the axis and rotates around the axis at the same time is smoothly supported below the heat transfer tube without applying an excessive frictional force. be able to.

In the welding apparatus according to the present disclosure, the lower support mechanism has a support state in which the first sphere is held at a position supporting the heat transfer tube and a retracted state in which the first sphere is retracted to a position not supporting the heat transfer tube. It is provided with a first switching mechanism capable of switching between.
According to the welding apparatus according to the present disclosure, the lower support mechanism can switch between the support state and the retracted state. Therefore, for example, when another mechanism is connected to the end of the heat transfer tube, the lower support mechanism and the lower support mechanism The lower support mechanism can be retracted from the heat transfer tube when necessary in order to avoid interference with other mechanisms such as the moving mechanism.

The welding apparatus according to the present disclosure includes an upper support mechanism for supporting the heat transfer tube from above, and the upper support mechanism has a second sphere in contact with the outer peripheral surface of the heat transfer tube and the second sphere in an arbitrary direction. The second holding portion that holds the heat transfer tube rotatably, the support state that holds the second sphere at a position that supports the heat transfer tube, and the retracted state that retracts the second sphere to a position that does not support the heat transfer tube are switched. It is provided with a possible second switching mechanism.
According to the welding apparatus according to the present disclosure, the position of the heat transfer tube can be reliably fixed by further supporting the heat transfer tube whose lower two points are supported by the lower support mechanism from above by the upper support mechanism. Further, since the second sphere can rotate in an arbitrary direction, it is possible to smoothly support the upper part of the heat transfer tube without applying an excessive frictional force to the heat transfer tube that moves along the axis and rotates around the axis at the same time. it can.

Furthermore, since the upper support mechanism can switch between the support state and the retracted state, for example, when another mechanism is connected to the end of the heat transfer tube, the upper support mechanism interferes with the other mechanism. The upper support mechanism can be retracted from the heat transfer tube to avoid it.

In the welding apparatus according to the present disclosure, the first distance along the axis from the welding position to the lower support mechanism arranged on the upstream side in the moving direction of the heat transfer tube is downstream from the welding position in the moving direction. It is shorter than the second distance along the axis to the downward support mechanism arranged on the side.
The lower support mechanism arranged on the upstream side in the moving direction of the heat transfer tube is arranged at a position closer to the welding position than the lower support mechanism arranged on the downstream side.

Therefore, the outer peripheral surface of the heat transfer tube that has not been welded is supported near the welding position, and the distance from the welding torch of the overlay welding mechanism to the outer peripheral surface of the heat transfer tube and the angle with the welding torch, etc., are the welding torch and the heat transfer tube. Fluctuations in the positional relationship of T can be suppressed. Further, the lower support mechanism arranged on the downstream side in the moving direction of the heat transfer tube is arranged at a position farther from the welding position than the lower support mechanism arranged on the upstream side. Therefore, the outer peripheral surface of the heat transfer tube having an uneven shape on the surface after welding is supported at a position away from the welding position, and the vibration when the uneven shape passes through the lower support mechanism is transmitted to the overlay welding mechanism. This can be suppressed, and the influence of minute positional fluctuations of the axial position of the heat transfer tube due to the wall thickness distribution of the weld bead can be suppressed.

The welding apparatus according to the present disclosure causes the cooling medium to flow into the heat transfer tube from one end on the upstream side in the moving direction of the heat transfer tube, and transfers the cooling medium from the other end on the downstream side in the moving direction of the heat transfer tube. A cooling mechanism for cooling the heat transfer tube by flowing it into the heat tube is provided.
According to the welding apparatus according to the present disclosure, the heat transfer tube heated by the build-up welding mechanism is appropriately and effectively cooled by the cooling medium in the vicinity of the welding position, and the change in the amount of penetration and the thermal stress due to the heat effect after welding are obtained. It is possible to appropriately suppress the warp deformation of the heat transfer tube due to the above.

The welding apparatus according to the present disclosure includes a plurality of the moving mechanisms for moving the plurality of the heat transfer tubes, a plurality of rotation mechanisms for rotating the plurality of the heat transfer tubes, and a plurality of welding devices for welding the outer peripheral surfaces of the plurality of the heat transfer tubes. A plurality of the heat transfer tubes are arranged in a state of being adjacent to each other in the horizontal direction orthogonal to the axial direction.
According to the welding apparatus according to the present disclosure, since a plurality of heat transfer pipes are arranged adjacent to each other, one worker can simultaneously monitor the welding state by the plurality of overlay welding mechanisms. The number of workers required for welding can be reduced.

The welding apparatus according to the present disclosure is arranged at a measurement position on the downstream side of the welding position in the moving direction of the heat transfer tube, and measures the outer diameter of the heat transfer tube passing through the measurement position, and / or said. It is equipped with a measuring mechanism that calculates the thickness of overlay welding.
According to the welding apparatus according to the present disclosure, by measuring the outer diameter of the heat transfer tube in which the spiral overlay welding is performed and / or calculating the thickness of the overlay welding, the heat transfer tube has the overlay thickness. It is possible to properly judge whether or not the welding specifications such as overlay surface roughness are properly satisfied, and control the moving mechanism that moves the heat transfer tube and the rotating mechanism that rotates the heat transfer tube so that the welding specifications are appropriate. it can.

The control method of the welding apparatus (200) described in the above-described embodiment is grasped as follows, for example.
The control method of the welding apparatus (200) according to the present disclosure is a control method of a welding apparatus that performs overlay welding on the outer peripheral surface of a cylindrical heat transfer tube arranged along an axis. A moving mechanism that moves the heat transfer tube along the axis, a rotation mechanism that rotates the heat transfer tube around the axis, and a rotation mechanism that rotates the heat transfer tube around the axis are fixed to an installation surface on which the welding device is installed and pass through a predetermined welding position. A build-up welding mechanism for welding while supplying a welding material to the outer peripheral surface of the heat transfer tube is provided, the moving mechanism moves the heat transfer tube along the axis, and the rotating mechanism moves the heat transfer tube. It is provided with a control step of controlling the welding apparatus so that the overlay welding mechanism spirally overlays welds on the outer peripheral surface of the heat transfer tube in a state of being rotated around the axis.

According to the control method of the welding apparatus (200) according to the present disclosure, since the overlay welding mechanism is fixed to the installation surface on which the welding apparatus is installed, a predetermined welding position with respect to the installation surface is fixed. Therefore, fluctuations in the positional relationship between the welding torch and the heat transfer tube, such as the distance from the welding torch of the overlay welding mechanism to the outer peripheral surface of the heat transfer tube and the angle with the welding torch, are suppressed, and welding is performed at each position in the longitudinal direction of the heat transfer tube. Fluctuations in the state are suppressed. As a result, it becomes possible to appropriately satisfy the welding specifications such as the overlay thickness and the overlay surface roughness, and to perform the spiral overlay welding on the outer peripheral surface of the heat transfer tube.

In the method for controlling a welding device according to the present disclosure, the welding device is arranged at a measurement position on the downstream side of the welding position in the moving direction of the heat transfer tube, and the outer diameter of the heat transfer tube passing through the measurement position. The control step comprises a measuring mechanism (60) for measuring and / or calculating the thickness of the overlay weld, and the control step is the outer diameter of the heat transfer tube measured by the measuring mechanism and / or the measuring mechanism. The moving speed at which the moving mechanism moves the heat transfer tube along the axis, and the rotation mechanism moves the heat transfer tube around the axis so that the thickness of the overlay weld measured by The rotation speed to be rotated and the rotation speed are controlled.
According to the control method of the welding apparatus according to the present disclosure, the moving speed and the rotating speed of the heat transfer tube are appropriately controlled so that the thickness of the overlay welding is within a predetermined range according to the measurement result by the measuring mechanism.

10 Movable trolley 11 Moving mechanism 12 Rotating mechanism 20 Overlay welding mechanism 21 Welding torch 21a Tungsten electrode 30 Lower support mechanism 31 First lower support 31a Sphere (first sphere)
32 Second lower support 32a Sphere (1st sphere)
33 Third lower support 33a Sphere (1st sphere)
33c Height adjustment mechanism (switching mechanism)
40 Upper support mechanism 40a sphere (second sphere)
40c Height adjustment mechanism 50 Cooling mechanism 60 Measuring mechanism 70 Main body 80 Imaging unit 85 Display 90 Control unit 200 Welding device MD Moving direction S Installation surface T Heat transfer tube Td Downstream end Tu Upstream end WB Welding bead

Claims (10)

A welding device that performs overlay welding on the outer peripheral surface of a cylindrical heat transfer tube arranged along the axis.
A moving mechanism that moves the heat transfer tube along the axis, and
A rotation mechanism that rotates the heat transfer tube around the axis, and
An overlay welding mechanism that welds while supplying welding material to the outer peripheral surface of the heat transfer tube that is fixed in position with respect to the installation surface on which the welding device is installed and passes through a predetermined welding position.
A control unit for controlling the moving mechanism, the rotating mechanism, and the overlay welding mechanism is provided.
In the control unit, the build-up welding mechanism is the outer periphery of the heat transfer tube in a state where the moving mechanism moves the heat transfer tube along the axis and the rotation mechanism rotates the heat transfer tube around the axis. A welding device that controls the surface to be spirally overlaid. A lower support mechanism for supporting the heat transfer tube from the vertically lower side is provided.
The downward support mechanism
A pair of first spheres that come into contact with two points in the circumferential direction of the outer peripheral surface of the heat transfer tube,
The welding apparatus according to claim 1, further comprising a first holding portion that rotatably holds the first sphere in an arbitrary direction. The lower support mechanism can switch between a support state in which the first sphere is held at a position that supports the heat transfer tube and a retracted state in which the first sphere is retracted to a position that does not support the heat transfer tube. The welding apparatus according to claim 2, further comprising a switching mechanism. It is provided with an upper support mechanism that supports the heat transfer tube from the upper side in the vertical direction.
The upper support mechanism
A second sphere that comes into contact with two points in the circumferential direction of the outer peripheral surface of the heat transfer tube,
A second holding portion that rotatably holds the second sphere in any direction,
A claim having a second switching mechanism capable of switching between a support state in which the second sphere is held at a position supporting the heat transfer tube and a retracted state in which the second sphere is retracted to a position not supporting the heat transfer tube. The welding apparatus according to claim 2 or 3. The first distance along the axis from the welding position to the lower support mechanism arranged on the upstream side in the moving direction of the heat transfer tube is the downward support arranged on the downstream side in the moving direction from the welding position. The welding apparatus according to any one of claims 2 to 4, which is shorter than the second distance along the axis to the mechanism. The cooling medium is allowed to flow into the heat transfer tube from one end on the upstream side in the moving direction of the heat transfer tube, and the cooling medium is discharged from the heat transfer tube from the other end on the downstream side in the moving direction of the heat transfer tube. The welding apparatus according to any one of claims 1 to 5, further comprising a cooling mechanism for cooling the heat transfer tube. A plurality of the moving mechanisms for moving the plurality of heat transfer tubes, and
A plurality of the rotating mechanisms for rotating the plurality of the heat transfer tubes,
A plurality of the overlay welding mechanisms for welding the outer peripheral surfaces of the plurality of heat transfer tubes are provided.
The welding apparatus according to any one of claims 1 to 6, wherein a plurality of the heat transfer tubes are arranged adjacent to each other in a horizontal direction orthogonal to the axial direction. The outer diameter of the heat transfer tube is measured at a measurement position downstream of the welding position in the moving direction of the heat transfer tube and passes through the measurement position, and / or the thickness of the overlay welding is calculated. The welding apparatus according to any one of claims 1 to 7, further comprising a measuring mechanism. It is a control method of a welding device that performs overlay welding on the outer peripheral surface of a cylindrical heat transfer tube arranged along an axis.
The welding device
A moving mechanism that moves the heat transfer tube along the axis, and
A rotation mechanism that rotates the heat transfer tube around the axis, and
It is provided with a build-up welding mechanism that welds while supplying welding material to the outer peripheral surface of the heat transfer tube that is fixed in position with respect to the installation surface on which the welding device is installed and passes through a predetermined welding position.
With the moving mechanism moving the heat transfer tube along the axis and the rotating mechanism rotating the heat transfer tube around the axis, the overlay welding mechanism spirals on the outer peripheral surface of the heat transfer tube. A method for controlling a welding device, which comprises a control process for controlling the welding device so as to perform overlay welding. The welding device is arranged at a measurement position on the downstream side of the welding position in the moving direction of the heat transfer tube, measures the outer diameter of the heat transfer tube passing through the measurement position, and / or overlay welding. Equipped with a measuring mechanism to calculate the thickness of
In the control step, the moving mechanism transmits the heat transfer tube so that the outer diameter of the heat transfer tube measured by the measuring mechanism and / or the thickness of the overlay welding measured by the measuring mechanism falls within a predetermined range. The method for controlling a welding apparatus according to claim 9, wherein the moving speed at which the heat pipe is moved along the axis and the rotation speed at which the rotating mechanism rotates the heat transfer tube around the axis are controlled.

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