KR20030040612A - A welding machine of convector plate for a batch annealing furnace - Google Patents

Abstract

PURPOSE: A welding apparatus of convector plate for batch annealing furnace is provided to suppress welding deformation and easily change welding part or position and automatically perform welding operation by pressing upper and lower plates to be adhered to radial rib using roller. CONSTITUTION: The welding apparatus of convector plate for batch annealing furnace comprises a pressing part(30) for pressing and holding rib of the convector plate along with tack welded upper and lower ventilation plates by a moving block(27) moved side to side along transfer screw(25) on a rotation block(26) rotationally inserted into rotation shaft and a pressing block(28) moved back and forth on the moving block(27); a rotation part for rotating the convector plate fixed to the front end of the rotation block(26) by a fixing nut(29) with the convector plate being penetratingly inserted into the rotation block(26) so that the convector plate is reciprocally rotated; and a welding part(40) for welding contact parts of the convector plate held by the pressing part(30) and upper and lower ventilation plates by transferring a welding torch(38) using a transfer box(34) moved side to side along a rack block(33) attached to the rear side of the rotation block, a back and forth moving rack bar(36) that is back and forth movably installed at one side of a filler metal feeding part(35) attached to the upper side of the transfer box(34), and a lowerable and liftable rack bar(37) inserted into the rack bar(36) in such a way that the lowerable and liftable rack bar(37) is moved up and down.

Description

A welding machine of convector plate for a batch annealing furnace}

The present invention relates to a convector plate welding apparatus, and more particularly, it is possible to suppress welding deformation by pressing the upper and lower plates attached to the radial ribs with a roller, to easily change the welding site or position, and to automatically weld the work. The present invention relates to a welding apparatus for a convector plate for annealing furnaces.

In general, a convector plate for a batch annealing furnace (BAF) is essential for improving the quality of the annealing material and improving the error rate by increasing the heat transfer efficiency of the hot coils that are deposited and annealed in the furnace. It plays a role, and is installed between the coil and the coil that is placed up and down in the inner cover (inner cover) inside the annealing furnace so that the heat transfer occurs quickly on the side of the coil so that the heat transfer of the coil can be performed uniformly. It is a key part of Dunlop.

Therefore, the convector plate is formed with a plurality of ribs 105 protruding radially around the hub 103, as shown by 101 in Figure 1 in order to ensure a smooth convection between the coils are placed up and down, Upper and lower ventilating plates 107 and 109 are attached to the upper and lower surfaces of the 105.

At this time, each of the vent boards 107, 109 is in contact with the upper and lower surfaces of the coil placed up and down, respectively, so that the corresponding contact portion of the coil is less heated than the other portions, and is smooth in the space between the coils. In view of the fact that it is a factor that prevents aeration, it is difficult to uniformly heat the coil as the number of ribs 105 increases. On the contrary, when the number of ribs 105 is reduced, the load on one rib 105 is increased by considering the coil weight when a coil of 20 tons is normally stacked in three to four stages, thereby contacting the ribs 105. Damage to skid marks or the like occurs on the upper and lower surfaces of the coil, that is, the left and right edge portions of the strip.

Therefore, the ribs 105 are designed to have an optimal number of ribs 105, for example, as shown in Fig. 1 in consideration of the opposite factors such as activation of convection and distribution of loads, even though the number of ribs 105 is optimized. Maintaining the flatness of the rib 105 vent plates 107 and 109 in direct contact with the coil is also an important factor to prevent failure of the coil, such as skid marks.

In particular, it is very important to suppress the deformation generated when the upper and lower vent plates 107 and 109 are welded to the upper and lower surfaces of the ribs 105. Until now, the upper and lower plates 107 and 109 are welded onto the upper and lower surfaces of the ribs 105, respectively. 101 is installed on a separate stand 111 as shown in FIG. 1, and then the length is circumferentially as shown in FIG. 2 while the welded ribs 105 and the vent plates 107 and 109 are kept horizontal. Deformation of the vent boards 107 and 109 due to welding has been suppressed by winding the plurality of deformation preventing frames 113 arranged in the direction and then welding them.

That is, after the convector plate 101 is installed on the fixing base 111 as above, the welding machine is operated, the opening and closing valve of the gas cylinder is opened, and then the flow rate is adjusted in the flow controller, and the welding current and the welding voltage value are measured in the welding machine. Set it. In this way, when the welding preparation is completed, the worker wears the protective equipment and takes the torch 115 held with one hand to the first welding part 121 shown in FIG. 2, and then presses the torch 115 switch 116. At this time, the positive pole of the power output from the welder is directly supplied to the welding site 121, the negative pole is supplied to the torch 115 via the controller 117 through a cable. The other power output from the welding machine also drives the controller 117 so that the filler wire 119 supplied from the filler wire reel 118 is supplied with the power of the negative pole while passing through the torch 115, and thus the welding site 121 When the arc is generated, an arc is generated, and at the same time, the shielding gas controlled by the flow controller is supplied through the hose and sprayed from the tip of the torch 115 to perform welding while protecting the welding part 121 from the atmosphere.

After the welding of the first welding part 121 is completed as described above, the next second welding part 122 is welded in the same manner, and after welding the upper and lower pairs of vent plates 107 and 109 to one rib 105. After dismantling each deformation prevention frame 113 and rotating the convector plate 101 in the fixing plate 111 to change the welding site, and then tighten the deformation prevention frame 113 to the corresponding rib 105 and then in the same manner As a result, the ventilation plates 107.109 are welded, and by repeating the welding process in turn, the upper and lower ventilation plates 107 and 109 are welded to the entire ribs 105.

By the way, in the conventional ventilation plate welding method, the operator must move the torch 115 and the deformation prevention frame 113 from time to time, and in particular, the deformation prevention frame 113 has to be repeatedly attached and detached to improve the work efficiency of the operator. In addition to deterioration, there is a need for additional work to bring the deformation between the deformation preventing frame 113 and to correct it, and the operator has to rotate the convector plate 101 several times in the adjacent state during welding. There is a risk of exist, and in particular, there was a problem that can cause various occupational diseases due to the fume (fume) and harmful light generated during welding.

Therefore, the present invention has been proposed to solve the problems of the conventional convector plate welding apparatus for the above-described annealing furnace, the upper and lower cylinders located on the rib in welding the upper and lower vent plates on the rib of the convector plate. By welding while pressing the substrate in the moving state, it is possible to suppress the welding deformation of the vent board, the removal of the pressing means for suppressing the welding deformation when the welding part is changed, the movement of the welding torch can also be made automatically. The purpose is to make it.

1 is a front view of a convector plate for explaining a conventional welding method for welding the upper and lower vent board to the convector plate.

2 is a cross-sectional view taken along the line AA of FIG.

3 is a perspective view of a convector plate welding apparatus according to the present invention.

4 is an exploded perspective view of FIG. 3;

5 is a partially omitted longitudinal cross-sectional view of FIG.

6 is a plan view of FIG.

7 is a partially omitted front view of FIG.

8 is an enlarged longitudinal sectional view of a partially omitted part of FIG.

9 is an enlarged front view of a part omitted main portion of FIG.

* Explanation of Signs of Major Parts of Drawings *

1: convector plate 5: rib

7,9: upper and lower ventilation plate 11: fixing stand

13: rotating shaft 21, 22, 23, 24: welding

25 feed screw 26 rotating block

27: moving block 28: pressure block

30 pressurization part 31 rotation part

33: rack block 34: transfer box

35: Yonggajae supply unit 36: post-war rack bar

37: lifting rack bar 38: welding torch

40 welding part 43 rotation axis

45: guide frame 51: support roller

55: pressure roller 66: filler wire

72: shielding gas hose 73: cable

74: gas cylinder 75: welding machine

Therefore, the present invention, in order to achieve the above object, in the convector plate welding apparatus which is configured to rotatably mount the convector plate by the rotating shaft on the base forming the base, on the rotating block rotatably inserted into the rotating shaft The moving block moving left and right along the feed screw and the pressing block moving back and forth on the moving block allow the relative rotation of the convex plater to the pressing block and the rotating block to press and hold the ribs of the convector plate together with the welded upper and lower vent plates. A rotating part which is inserted through and rotates the convector plate fixed to the tip by a fixing nut, and a transfer box installed to move left and right along the rack block attached to the rear of the rotating block and attached to the upper side of the transfer box. And the forward and backward rack bar installed on one side of the filler metal supply unit which can be moved back and forth Provides a convector plate welding device comprising a welding portion configured to transfer a welding torch by lifting and lowering rack bars inserted into the rack bars to weld the contact portions of the convector plate and the upper and lower vent plates to be gripped by the pressing unit. do.

Hereinafter, a convector plate welding apparatus for annealing furnaces according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Convector plate welding apparatus according to the present invention, as shown in the assembly state in Figure 3, using the fixing rod 11 for welding the vent plates (7, 9) to the convector plate 1, as in the conventional welding apparatus Ventilation plates 7 and 9 are provided on upper and lower surfaces of the plurality of ribs 5 extending radially from the convector plate 1 while rotating the convector plate 1 rotatably mounted on the fixing stand 11. Among the ribs 5 and the convex plate 1 of each of the ribs 5 and the pressurized portion 30 for holding and holding the ribs 5 and the ventilation plates 7 and 9 to be welded to the ribs 5 so as to weld the ribs 5 and 9 together. Rotating part 31 for rotating the convector plate 1 on the holder 11 to select a specific rib (5) for welding work, and welding power supplied from the outside and shielding gas and filler wire 66 Welds 40 directly used to weld ribs 5 and upper and lower vent plates 7, 9 Is installed.

Here, the pressing unit 30 is composed of a combination of blocks such as the rotating block 26, the moving block 27 and the pressing block 28 again as shown in Figures 3 to 9 rotating block 26 Rotation about the movement block 27 to move from side to side on the guide frame 45 of the rotary block 26 along the feed screw 25 and the pressure block mounted on the movement block 27 to slide back and forth ( 28 is pressurized and held between the ribs 5 extending from the hub 3 of the convector plate 1 and the vent plates 7 and 9 to be welded to the ribs 5.

The rotating block 26 is again extended to the left and right from both sides of the square body and the rotating shaft 43 extending to the rear of the body and the body located in front of the holder 11 as shown more clearly in FIG. It consists of a guide frame 45, wherein the rotating shaft 43 is inserted into the mounting hole 42 of the holder 11, as shown in Figure 5 to be rotatable by a pair of front and rear bearings 77 In the mounting hole 42 by the rotational force of the driving gear 80 supported and driven through the driven gear 78 attached to the rear end of the rotary shaft 43 and the driving gear 79 engaged with the gear 78. Rotation, guide frame 45 is to be inserted through the feed screw 25 to move the moving block 27 to the left and right bent at both ends as shown in Figures 3, 4 and 6 at a right angle.

At this time, the feed screw 25 has a left side 46 first, that is, in the direction of the right hand screw, and the right side 47 the left line around the portion inserted through the body portion of the rotary block 26 as shown in FIG. In other words, each thread is machined in the left-hand direction, facing the left and right moving block 27 screwed to the left and right helix 46, 47 on both sides while repeating the forward and reverse rotation by the drive motor 41 connected to one end It is intended to move toward or away from.

As described above, the movable block 27 which moves to the inside and the outside of the rotary block 26 along the guide frame 45 is a pair of upper and lower frame plates bent in a "b" shape and slides penetrated to the left and right of the body. A pair of left and right support rollers 51 are rotatable between the upper and lower support frames 49 which are fitted on the guide frame 45 through the guide holes 81 and are bent in a direction parallel to the guide holes 81. The slide groove 52 is machined in the front and rear directions on the upper and lower bodies.

In addition, the pressing block 28 coupled to the sliding groove 52 of the movable block 27 so as to slide back and forth is also a pair of upper and lower frame plate bent in a "b" shape similar to the movable block 27. The pressure frame 54 is bent in parallel along the guide frame 45 so as to face the support frame 49 of the movable block 27, and a pair of pressure is applied between the upper and lower plates of the pressure frame 54. The roller 55 is attached to the support roller 51 at the position which can be rotated, respectively. In addition, a through hole 82 in which the lead screw 53 is fitted in the idle state is formed in the rear surface of the pressure block 28, in which the lead screw 53 is screwed to the rear surface of the moving block 27. .

As shown in FIG. 5, the rotary part 31, which is configured to rotate the convector plate 1 separately from the pressing part 30, has a rotary shaft 13 on which the convector plate 1 is installed and the rotary shaft 13. And a driving gear (83) engaged with the driven gear (83) attached to the fixing nut (29) and the outer peripheral surface of the rear end of the rotary shaft (13) for fixing the convector plate (1) to the tip of the driven gear (84). It consists of a drive motor 85 for driving the rotary shaft 13 through the rotation, wherein the rotary shaft 13 is a rotary block through a pair of bearings 86 fitted to the front and rear ends of the inner peripheral surface of the rotary block 26 It is rotatably supported relative to (26).

In addition, the contact portion between the rib 5 of the convector plate 1 gripped by the pressing unit 30 and the upper and lower venting plates 7 and 9 while rotating together with the pressing unit 30 by the rotating unit 31 is welded. Welding portion 40 is to be shown, as shown in the drawings, the rack block 33, which serves as a guide rail, the transfer box 34 to move to the left or right from each other along the rack block 33, To the filler metal supply unit 35 for supplying the filler wire to the welding torch 38, the front and rear advancing rack bar 36, which is elastically mounted on the front of the filler metal supply unit 35, and the front of the rack bar 36. Lifting rack bar 37 is inserted and installed, and the flexible torch 38 is inserted and fixed to the fixing ring 71 of the bottom of the lifting rack bar 37.

Here, the rack block 33 is extended in the form of a square rod, as shown in Figures 3 to 6, the rotation axis of the rotary block 26 in a state in which the rack 61 is processed on one side of the extended side (43) It is attached to the rear side and rotates about the rotating shaft 43 together with the press part 30. As shown in FIG. In addition, as shown in FIGS. 3 and 6, the transfer box 34 has a pair of left and right inserts installed on both sides of the rack block 33, and the pinion gear 62 engaged with the rack 61 rotates therein. In this case, the pinion gear 62 meshes with the rack 61 by rotationally driving the worm wheel 88 mounted together on the rotation shaft 87 with the worm 89 connected to the drive motor 63. While moving the transfer box 34 to the left and right on the rack block 33.

The filler metal supply unit 35 attached to the upper surface of the transfer box 34 includes a feed casing 90, a pair of transfer reels 91 mounted inside the casing 90, and the like. A drive motor 64 for rotating the transfer reel pair 91 and a filler wire 65 wound around the filler wire 66 supplied to the welding torch 38 through the transfer reel 91. The gas casing 74 and the shielding gas hose 72 extending from the cable 73 and the cable 73 are connected to the supply casing 90, respectively.

The forward and backward rack bar 36 mounted on the front side to which the torch 38 of the filler material supply casing 90 is connected is a rack bar guide casing attached to the front surface of the supply casing 90 as shown in FIGS. 3 and 6. The guide casing 67 is moved in and out according to the rotation of the pinion gear 68 inserted into the 67 and inserted into the front end of the casing 67. In addition, the elevating rack bar 37 penetrated up and down at the front end of the forward and backward rack bar 36 is moved up and down by rotating the pinion gear 69 inserted into the front end portion of the forward and backward rack bar 36. The welding torch 38 is fixed by the fixing ring 71 mounted at the lower end thereof.

Finally, the welding torch 38 fixed to the lower end of the elevating rack bar 37 is a predetermined position in which the fixing ring 71 is located in accordance with the movement of the transfer box (), the forward and backward rack bar () or the elevating rack bar (). It is made of a flexible material to move smoothly to the point of, and is connected to the shielding gas hose 72 and the cable 73 through the filler material supply 35 as shown in FIG.

Referring to the operation of the convector plate welding apparatus according to the present invention configured as described above are as follows.

First, the convector plates 1 to be welded to the upper and lower vent plates 7 and 9 are inserted into the rotary shaft 13 and then fixed to the front end of the rotary block 26 by the fixing nuts 29. Then, when the driving motor 41 of the pressing unit 30 is operated through a control panel (not shown), the screw 46 of the feed screw 25 rotates while the feed screw 25 is rotated by the rotational force of the motor 41. The left and right moving blocks 27 screwed to the 47 are moved in a direction closer or away from each other according to the rotational direction of the screw 25, that is, in a direction of approaching or spaced apart.

In this way, when the moving block 27 reaches the set welding start point, the motor 41 is stopped and the lead screw 53 is rotated so that the pressure block 28 moves backward along the sliding groove 52 of the moving block 27. Rib 5 of convector plate 1 interposed between supporting roller 51 of moving block 27 and pressing roller 55 of pressing block 28 as shown in FIG. The upper and lower vent plates 7 and 9 are gripped by pressure.

Then, when the pressure holding state of the convector plate 1 and the upper and lower ventilation plates 7 and 9 is confirmed, the welding current, the welding voltage value and the welding speed value are set through the control panel, and the valve 74 of the cylinder 74 is opened. By supplying the shielding gas to the torch 38 through the hose 72 while controlling the discharge flow rate by the flow controller at the same time, the welding machine 75 main switch is turned on.

When the welding preparation is completed as described above, the welding start button of the control panel is pressed so that the positive pole of the power output from the welding machine 75 is directly supplied to the welding part, and the negative pole is the welding torch 38 through the cable 73. To be supplied. At this time, the power supplied from the welding machine 75 and supplied to the filler metal supplying unit 35 drives the motor 64 so that the filler wire 66 wound around the filler metal reel 65 is supplied to the torch 38. It is applied to contact the welding portion, for example, the contact portion 21 to generate an arc. At the same time, the shielding gas supplied from the cylinder 74 is sprayed from the torch 38 through the hose 72 so that welding is performed while protecting the molten part from the atmosphere.

When welding is started, the transfer box 34 driving motor 63 of the welding part 40 and the feed screw 25 driving motor 41 switch of the pressurizing part 30 are simultaneously turned on. Accordingly, when the worm 89 and the worm wheel 88 directly connected to the motor 63 rotate, the pinion gear 62 mounted on the same shaft 87 as the worm wheel 88 rotates. The gear 62 is moved to the left and right on the engaged rack 61, at this time, the transfer box 34 is mounted on the pinion gear 62 also slides on the rack block 33 to the left and right.

At the same time, the welding torch 38 connected to the filler metal supply unit 35 and the supply casing 90 installed above the transfer box 34 is supported with the supporting roller 51 and the pressure roller 55 as shown in FIGS. 8 and 9. The welding proceeds while moving left and right along the contact portion of the rib 5 of the convector plate 1 and the upper and lower vent plates 7 and 9, that is, for example, the welding portion 21, which are pressed and held between them.

At this time, while the drive motor 41 of the pressing unit 30 is driven to rotate, the feed screw 25 connected to the motor 41 is rotated, and thus the moving block 27 screwed to the feed screw 25. ) And the pressure block 28 coupled to the block 27 is moved left and right along the guide frame 45, and thus the support roller 51 and the pressure roller 55 mounted on the respective blocks 27 and 28. Rotation while pressing the welding site 21 to roll on the vent board (7, 9) without frictional resistance so that welding is made while deformation does not occur in the welding site (21).

As the welding progresses and the torch 38 reaches the end point of welding, the welding end button on the control panel and the switches of the driving motors 41 and 63 are turned off, and the rack bar guide casing for welding the next welding portion 22 is performed. The torch 38 is moved over the next welded portion 22 by turning the pinion gear 68 of 67 to advance and retreat the forward and backward rack bar 36 engaged with the gear 68. Then, the welding portion 22 is welded while suppressing welding deformation in the same manner as above.

In this way, when the welding to the upper welding area (21, 22) is finished and the welding torch 38 is located in the initial welding ready position, the welding stop button of the control panel to terminate the welding, and then After the drive motor 41 is also switched off, the rotary block drive motor 80 switch on the control panel is turned on to be welded by the drive gear 79 connected to the motor 80 so as to weld the welding parts 23 and 24 on the lower side. By rotating the driven gear 78 of the rotating shaft 43, the rotary block 26 is rotated in the mounting hole 42 of the fixing table 11. Accordingly, when the rotary block 26 is rotated 180 ° and completely conducted at the initial position, the motor 80 switch on the control panel is turned off, and then the ribs 5 and the up and down are the same as when welding the welding parts 21 and 22 are performed. The welding portions 23 and 24 between the vent plates 7 and 9 are welded without causing welding deformation.

The next rib 5 after welding the upper and lower vent plates 7, 9 on any of the plurality of ribs 5 of the radially extending convector plates 1, which are opposed to each other. Another ventilation plate (7,9) is welded to the same, and for this purpose, first, by removing the lead screw (53) to separate the pressure block (28) from the rib (5) and the ventilation plate (7,9), and then the control panel The drive shaft 85 of the rotary shaft 13 is turned on to drive the driven gear 83 of the rotary shaft 13 through the drive gear 84 connected to the motor 85. Accordingly, as the rotating shaft 13 rotates at an angle within the rotating block 26, the convector plate 1 fixed to the rotating shaft 13 by the fixing nut 29 also rotates by the same angle. . In this way, when the next welding part 21 of the convector plate 1 reaches a horizontal state, the drive motor 85 is switched off, and the next welding parts 21, 22, 23 and 24 are moved as before. Weld sequentially.

In this way, by welding and rotating the convector plate 1 repeatedly, the welding of the vent plates 7, 9 to the entire rib 5 is completed, and then the fixing nut 29 is released to release the fixing nut 29 from the rotating shaft 13. By removing the convector plate 1, the entire welding operation is completed.

As described above, according to the convector plate welding apparatus for the annealing furnace according to the present invention, in the welding of the upper and lower vent boards to each rib of the convector plate, a separate deformation preventing frame for preventing deformation due to welding is provided. The support roller and the pressure roller can be welded while suppressing the welding deformation as much as possible by the support roller and the pressure roller without any hassle, thereby reducing the work fatigue of the worker and greatly improving the work productivity. In addition, since the worker does not weld directly, it is possible to prevent the worker's damage due to the high temperature heat and harmful rays generated during welding.

Claims (3)

In the convector plate welding device, which is configured to rotatably mount the convector plate 1 by the rotation shaft 13 on the base 11. On the rotary block (26) rotatably inserted into the rotary shaft (13) to the moving block 27 to move left and right along the feed screw 25 and to the pressure block (28) moving back and forth on the moving block (27) The press portion 30 for pressing and holding the ribs 5 of the convector plater 1 together with the upper and lower vent plates 7 and 9, and through-insertion to allow relative rotation to the rotary block 26. Left and right along the rotating part 31 and the rack block 33 attached to the rear of the rotating block 26 to rotate the convector plate 1 fixed to the front end by the fixing nut 29. Forward and backward rack bar 36 and the rack bar 36 is installed to be movable back and forth on one side of the transfer box 34 and the filler metal supply portion 35 attached to the upper portion of the transfer box 34 so as to be movable to the The welding torch 38 is conveyed by the elevating rack bar 37 inserted to move upward and downward in the Consisting of the welding portion 40 is configured to weld the contact portion 21, 22, 23, 24 of the convector plate 1 and the upper and lower vent plates 7, 9 held by the pressure portion 30 Convector plate welding device, characterized in that. According to claim 1, The pressing unit 30 is a rotating shaft 43 which is rotatably inserted into the mounting hole 42 of the holder 11 by the motor 41 is attached to the back and the guide frame 45 is extended to the left and right long Rotation block 26 attached to both sides, the guide frame 45 is inserted to the left and right and is conveyed to the left and right by a feed screw 25 having left and first divided spirals 46 and 47, the guide frame Slidingly fitted into the movable block 27 and the sliding groove 52 of the upper and lower surfaces of the movable block 27 is mounted on the support frame 49, which is bent along the 45. The support roller is conveyed back and forth along the slide groove 52 by the lead screw 53 coupled to the rear side, and the support roller on the pressing frame 54 bent along the guide frame 45 to face the support frame 49. The pressure block 28 is equipped with a pair of pressure rollers 55 so as to correspond to the (51). Made convector plate welding equipment, characterized in that. According to claim 1, The welding part 40 is inserted into the rack block 33 attached to the rear of the rotating shaft 43 of the rotary block 26, the left and right sides of the rack block 33 and the rack 61 of the rack block 33 and A pair of transfer box 34 which is adapted to move left and right as the pinion gear 62 built to engage is rotated by the motor 63, and is attached to an upper side of the transfer box 34 to the motor 64. The filler metal supply unit 35 for supplying the filler wire 66 extracted from the filler wire reel 65 to the welding torch 38 and the rack bar guide casing attached to the front of the filler wire supply unit 35 according to the driving of the filler wire ( 67, the forward and backward rack bar 36, which is inserted into the guide casing 67 and moved forward and backward by the pinion gear 68 inserted into the guide casing 67, and is inserted through the front end of the rack bar 36, 69) is to move up and down and the lifting ladder which is torch fixing ring 71 is coupled to the bottom It is connected to the gas cylinder 74 and the welding machine 75 through the kba 37 and the shielding gas hose 72 and the cable 73, and is fixed to the bottom of the rack bar 37 by the fixing ring 71. Convector plate welding device, characterized in that consisting of a flexible torch (38) fitted.