A positioning tool for welding a shell leg

Abstract

The application relates to the technical field of container tank processing, in particular to a positioning tool for welding of a support leg of a head, which comprises a fixing disc, a center positioning pipe and a side positioning pipe arranged on the fixing disc, the center positioning pipe is used for connecting a first discharge pipe on the head, the side positioning pipe is used for connecting a second discharge pipe on the head, positioning barrels for inserting the support leg are arranged on the fixing disc, the positioning barrels are arranged in multiple, and the multiple positioning barrels are uniformly arranged on the circumferential side of the center positioning pipe. The center positioning pipe and the side positioning pipe are matched to realize the positioning of the head, the support leg is positioned through the positioning barrels, the support leg is quickly positioned on the head, and the convenience of subsequent welding is improved under the premise of ensuring the installation position of the support leg.

Description

Technical Field

[0001] This application relates to the field of container and storage tank processing technology, and in particular to a positioning fixture for welding head and support legs. Background Technology

[0002] End caps are components used to seal the ends of containers to achieve media isolation. Also known as end covers, they are mainly used for the upper and lower bottoms of pressure vessels. Based on their geometric shapes, they can be divided into several types, including spherical, elliptical, dished, spherical crown, conical, and flat caps. End caps are widely used in storage tanks, reactors, and gas cylinders in industries such as petrochemicals, nuclear power, food, and pharmaceuticals. For the lower bottom end caps in vertical storage tanks, during use, it is necessary to weld support legs, connecting pipes, and other components onto the end cap.

[0003] In the existing technology, when welding the support leg to the head, it is necessary to first weld a first discharge pipe at the center position of the bottom side of the head, and then weld a second discharge pipe to the side of the first discharge pipe, while ensuring that the length of the second discharge pipe is less than the length of the first discharge pipe. Then, the support leg positioning line is marked on the periphery of the first discharge pipe on the head. The support leg is then moved to the marked position and fixed manually or with the help of tools. Finally, the support leg is welded to the head using a welding gun.

[0004] However, in practical applications, multiple legs (commonly four) are usually welded to the bottom of the end cap, and it is necessary to ensure that the installation positions of the four legs are equidistant from the central axis of the end cap. The aforementioned manual marking method is cumbersome, and the marking position is difficult to guarantee. This can easily lead to differences in the distance between the welded legs and the central axis of the end cap, causing the center of gravity of the end cap to deviate after the legs are installed, resulting in instability and affecting the normal use of the end cap. Moreover, when a large number of end caps of the same specification are produced, the direction of manual marking needs to be repeated multiple times, making the overall process inconvenient and unfavorable for use. Utility Model Content

[0005] In order to improve the convenience of outrigger positioning while ensuring accurate welding position of the outrigger, this application provides a positioning fixture for welding head outriggers.

[0006] This application provides a positioning fixture for welding head support legs, which adopts the following technical solution: A positioning fixture for welding end cap legs includes a fixed plate, a central positioning tube and a side positioning tube disposed on the fixed plate. The central positioning tube is used to connect to a first discharge pipe on the end cap, and the side positioning tubes are used to connect to a second discharge pipe on the end cap. The fixed plate is provided with positioning cylinders for inserting the legs. Multiple positioning cylinders are provided, and the multiple positioning cylinders are evenly spaced around the central positioning tube.

[0007] By adopting the above technical solution, during use, the support legs are placed into the positioning cylinder, and then the end cap is placed on the support legs. The center positioning tube is coaxially connected with the first discharge tube to ensure the center positioning of the end cap. This ensures that the distance between multiple support legs and the center axis of the end cap is the same. In addition, the side positioning tube is connected to the second discharge tube to achieve the circumferential positioning of the end cap. Thus, the support legs and end cap can be quickly positioned, and the distance between multiple support legs and the center axis of the end cap is the same, which facilitates subsequent welding and makes the overall use more convenient.

[0008] Preferably, the fixing plate includes a base plate, horizontal bars and vertical bars disposed on the base plate, and sector blocks disposed on the base plate. The horizontal bars and vertical bars are arranged perpendicular to each other, and the horizontal bars and vertical bars divide the base plate into four placement areas. A sector block can be detachably connected to any of the placement areas. Several positioning cylinders are disposed on each sector block, and a snap-fit ​​assembly is disposed between two adjacent sector blocks.

[0009] By adopting the above technical solution, during use, the detachable connection of the sector blocks, combined with the positioning of the sector blocks in the placement area, allows workers to easily replace sector blocks of different sizes according to the different sizes of the end caps being processed. This changes the distance between the positioning cylinder and the central positioning column, thus adapting to end caps of different sizes. After multiple sector blocks are installed, they are snapped together into a whole by the snap-fit ​​assembly to prevent one sector block from sliding and affecting the positioning accuracy of the positioning cylinder, which is more conducive to use.

[0010] Preferably, the snap-fit ​​assembly includes a rotating plate that rotates on a sector block, a rotating shaft that rotates on another sector block, and a limiting block fixed on the rotating shaft. The rotating plate has a clearance hole, and the limiting block passes through the clearance hole and rotates to press the rotating plate onto the sector block.

[0011] By adopting the above technical solution, when the sector block is placed on the base plate, simply move the rotating plate to allow the limit block to pass through the clearance hole, and then rotate the limit block to press the rotating plate onto the sector block. This achieves the goal of locking two adjacent sector blocks into a whole. By adjusting all the locking components in sequence, four sector blocks can be locked into a whole, thereby preventing the position of any sector block from changing.

[0012] Preferably, the sector block has a groove, the positioning cylinder has a mounting plate fixed on it, the mounting plate is fitted into the groove, and the mounting plate is also provided with a positioning bolt, one end of which passes through the mounting plate and is threaded to the bottom wall of the groove.

[0013] By adopting the above technical solution, the positioning cylinder is positioned by the groove and then fixed by the positioning bolt, thereby realizing the detachable replacement of the positioning cylinder, which is more conducive to actual use.

[0014] Preferably, the groove is provided in two sets, and the two sets of grooves are respectively provided on opposite sides of the sector block, and the distance between the two sets of grooves and the central positioning tube is different.

[0015] By adopting the above technical solution, users can choose to install the sector block on the front or back side as needed, adapting to different installation requirements, through the setting of two types of slots.

[0016] Preferably, an outer sleeve is coaxially fixed to the central positioning tube, and there is a gap between the end of the outer sleeve away from the fixed plate and the end of the central positioning tube away from the fixed plate.

[0017] By adopting the above technical solution, when in use, the outer sleeve is set to form a stepped surface at the end of the central positioning tube, thereby adapting to the connection of first discharge tubes of different sizes.

[0018] Preferably, the side positioning tube includes a fixed tube fixed on a fixed plate, a sliding tube slidably disposed on the fixed tube, and an abutment bolt threaded on the fixed tube for positioning the sliding tube. The sliding tube is coaxially disposed with the fixed tube and slides along its own axial direction. One end of the abutment bolt passes through the fixed tube and abuts against the side wall of the sliding tube. A joint is provided at the end of the sliding tube away from the fixed tube, and a positioning groove for embedding the second discharge tube is provided at the end of the joint.

[0019] By adopting the above technical solution, when in use, the sliding tube drives the connector to move synchronously. After the positioning groove is fitted onto the second discharge tube, the sliding tube is tightened by screwing the abutment bolt, thereby achieving the positioning of the sliding tube. The overall use is simple and convenient, and it is more conducive to the connection between the second discharge tube and the connector.

[0020] Preferably, the connector is detachably connected to the sliding tube.

[0021] By adopting the above technical solution, the applicability of the device can be improved by disassembling and replacing different types of connectors during use.

[0022] Preferably, the sector block has a weight-reducing groove.

[0023] By adopting the above technical solution, the weight of the sector block is reduced by the weight-reducing groove, making it easier for staff to move and replace the sector block.

[0024] In summary, this application includes at least one of the following beneficial technical effects: 1. Place the support legs into the positioning cylinder, then place the end cap on the support legs, and ensure the center positioning of the end cap by coaxially connecting the central positioning tube with the first discharge tube. This ensures that the distance between the multiple support legs and the central axis of the end cap is the same. Then, connect the side positioning tube to the second discharge tube to achieve circumferential positioning of the end cap. This enables rapid positioning of the support legs and the end cap, and also ensures that the distance between the multiple support legs and the central axis of the end cap is the same, which facilitates subsequent welding and makes the overall use more convenient. 2. By using the combination of sector blocks, horizontal bars, vertical bars and snap-fit ​​components, workers can replace the corresponding sector blocks according to the different sizes of end caps and legs to ensure that the installation position of the legs meets the requirements, thus improving overall practicality; 3. By using the outer sleeve, fixed sleeve, sliding sleeve and connector, the device can be connected to first and second discharge pipes of different sizes, further improving its adaptability. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the end cap installation state, which is the main feature of Embodiment 1 of this application; Figure 2 This is an isometric schematic diagram of the main tooling structure in Embodiment 1 of this application; Figure 3 This is an isometric schematic diagram of the main tooling structure in Embodiment 2 of this application; Figure 4 This is an exploded view of the overall structure of the tooling in Embodiment 2 of this application; Figure 5 yes Figure 3 The image mainly shows a magnified view of part A of the structure. Figure 6 This is an isometric schematic diagram of the side positioning tube structure, which is the main feature of Embodiment 2 of this application.

[0026] Reference numerals: 1. Fixed plate; 11. Base plate; 12. Horizontal bar; 13. Vertical bar; 14. Sector block; 15. Embedded groove; 16. Weight reduction groove; 2. Center positioning tube; 3. Side positioning tube; 31. Fixed tube; 32. Sliding tube; 33. Abutment bolt; 34. Joint; 4. Positioning cylinder; 5. Snap-fit ​​assembly; 51. Rotating plate; 52. Rotating shaft; 53. Limiting block; 54. Clearance hole; 6. Mounting plate; 7. Positioning bolt; 8. Outer sleeve; 9. End cap; 91. First discharge pipe; 92. Second discharge pipe; 93. Support leg. Detailed Implementation

[0027] The following is in conjunction with the appendix Figure 1 -Appendix Figure 6 This application will be described in further detail.

[0028] This application discloses a positioning fixture for welding head and leg supports.

[0029] Example 1: Reference Figure 1 and Figure 2 A positioning fixture for welding the support legs of a head includes a fixed plate 1, a central positioning tube 2, and side positioning tubes 3. The fixed plate 1 has a disc-shaped structure. The central positioning tubes 2 and the fixed plate 1 are coaxially arranged, and the bottom end of the central positioning tubes 2 is welded and fixed to the fixed plate 1. The top end of the central positioning tubes 2 is vertically upward. The side positioning tubes 3 are spaced apart on one side of the central positioning tubes 2, and the bottom end of the side positioning tubes 3 is welded and fixed to the fixed plate 1. The top end of the side positioning tubes 3 is vertically upward. In this embodiment, the diameter of the central positioning tube 2 is larger than the diameter of the first discharge tube 91 on the head 9, that is, the central positioning tube 2 is used for the insertion of the first discharge tube 91. The diameter of the side positioning tubes 3 is larger than the diameter of the second discharge tube 92 on the head 9, that is, the side positioning tubes 3 are used for the insertion of the second discharge tube 92.

[0030] Reference Figure 1 and Figure 2 A positioning cylinder 4 is also welded and fixed on the fixed plate 1. The positioning cylinder 4 is used to insert the support leg 93. Multiple positioning cylinders 4 are provided, and the multiple positioning cylinders 4 are evenly distributed around the periphery of the central positioning tube 2. Since there are usually four support legs 93 welded on the end cap 9, and the included angle between two adjacent support legs 93 is ninety degrees, the number of positioning cylinders 4 in this application should be a multiple of four. In this embodiment, eight positioning cylinders 4 are provided. The eight positioning cylinders 4 are divided into two groups with different cylinder diameters, and the two groups of positioning cylinders 4 are distributed alternately around the periphery of the central positioning tube 2. That is, when in use, the operator can select to use different positioning cylinders 4 according to the different thicknesses of the support legs 93 welded to the end cap 9.

[0031] Reference Figure 1 and Figure 2 In use, after the first discharge pipe 91 and the second discharge pipe 92 are fixed to the end cap 9 by spot welding, the four legs 93 of the same size are placed in the corresponding positioning cylinders 4. Then, the end cap 9 is moved so that the first discharge pipe 91 is inserted into the central positioning tube 2, thereby achieving coaxial positioning of the end cap 9 and the directional positioning tube. Then, the end cap 9 is rotated so that the second discharge pipe 92 is aligned with the side positioning tube 3. The end cap 9 is then moved downward until the second discharge pipe 92 is inserted into the side positioning tube 3 and the end cap 9 is placed stably. At this time, the top of the leg 93 abuts against the bottom wall of the end cap 9, and the positioning of the leg 93 and the end cap 9 is completed. Subsequently, the workers can weld the leg 93 and the end cap 9 one by one to fix them. After the welding is completed, the end cap 9 can be removed as a whole.

[0032] Reference Figure 2An outer sleeve 8 is coaxially fixed to the central positioning tube 2. The outer sleeve 8 has multiple layers, and the multiple layers of outer sleeve 8 are arranged concentrically. The top surface of the innermost outer sleeve 8 is lower than the top surface of the central positioning tube 2, and the height of the top surface of the outer sleeve 8 between two adjacent layers of outer sleeve 8 is lower than the height of the top surface of the inner outer sleeve 8. That is, a stepped structure is formed between the multiple outer sleeves 8 and the central positioning tube 2. In this embodiment, the outer sleeve 8 is set to two layers. Through the cooperation of the two layers of outer sleeve 8 and the central positioning tube 2, the connection and positioning of the first discharge tube 91 with different diameters are realized, which improves the overall practicality of the device.

[0033] Reference Figure 1 and Figure 2 In actual use, since the finished product requires the length of the second discharge pipe 92 on the end cap 9 to be less than the length of the first discharge pipe 91, and the length of the side positioning pipe 3 in this device is less than the length of the center positioning pipe 2, in order to ensure that the second discharge pipe 92 can be inserted into the side positioning pipe 3 after the first discharge pipe 91 is inserted into the center positioning pipe 2, it is necessary to ensure that the length of the second discharge pipe 92 is sufficient to connect to the second discharge pipe 92 when processing the second discharge pipe 92. After the support leg 93 is welded, the excess section on the second discharge pipe 92 is removed by cutting, thereby realizing the processing of the end cap 9.

[0034] Example 2: Reference Figure 3 and Figure 4 The difference between this embodiment and Embodiment 1 is that, in this embodiment, the fixing plate 1 includes a base plate 11, a horizontal bar 12, a vertical bar 13, and a sector-shaped block 14. The base plate 11 is a circular plate structure. The horizontal bar 12 and the vertical bar 13 are welded and fixed to the base plate 11, and the horizontal bar 12 and the vertical bar 13 are perpendicular to each other, forming a cross-shaped frame structure. The corresponding horizontal bar 12 and vertical bar 13 cooperate to evenly divide the area above the base plate 11 into four sector-shaped placement areas. The sector-shaped block 14 is designed... There are four fan-shaped blocks 14, and the four fan-shaped blocks 14 are placed in four installation areas respectively. When in use, after placing the fan-shaped block 14 in the installation area, move the fan-shaped block 14 so that the two right-angled sides of the fan-shaped block 14 fit against the side walls of the horizontal bar 12 and the vertical bar 13, and the installation of one fan-shaped block 14 is completed. At the same time, in order to ensure that the four fan-shaped blocks 14 form a whole, that is, to prevent one or more fan-shaped blocks 14 from being misaligned, a set of snap-fit ​​components 5 is provided between each pair of adjacent fan-shaped blocks 14.

[0035] Reference Figure 3 and Figure 5The snap-fit ​​assembly 5 includes a rotating plate 51, a rotating shaft 52, and a limiting block 53. One end of the rotating plate 51 is rotatably connected to a sector block 14, and the other end of the rotating plate 51 has an clearance hole 54. In this embodiment, the clearance hole 54 is a rectangular hole. The rotating shaft 52 is rotatably connected to another rotating plate 51 located adjacent to the rotating plate 51, and the diameter of the rotating shaft 52 is smaller than the width of the clearance hole 54. The limiting block 53 is integrally formed on the top end of the rotating shaft 52, and the limiting block 53 is also a rectangular block structure. The width of the limiting block 53 is smaller than the width of the clearance hole 54, the length of the limiting block 53 is greater than the width of the clearance hole 54, and the length of the limiting block 53 is less than the length of the clearance hole 54.

[0036] Reference Figure 3 and Figure 5 In use, by rotating the limiting block 53 so that its length direction is parallel to the length direction of the clearance hole 54, the rotating plate 51 can be moved until the limiting block 53 passes through the clearance hole 54. When the rotating plate 51 rotates to abut against the sector block 14, the limiting block 53 is rotated until its length direction is perpendicular to the length direction of the clearance hole 54. The limiting block 53 can then press the rotating plate 51 onto the sector block 14. Thus, the cooperation between the limiting block 53 and the rotating plate 51 enables two adjacent sector blocks 14 to be snapped together. By performing the above steps one by one on several sets of snapping components 5, four sector blocks 14 can be connected into a whole.

[0037] Reference Figure 3 and Figure 4 Meanwhile, the positioning cylinder 4 is detachably connected to the sector block 14, and each sector block 14 is provided with several positioning cylinders 4. In this embodiment, the positioning cylinder 4 is preferably set to two. Specifically, a groove 15 is opened on the sector block 14, and a circular mounting plate 6 is integrally formed at the bottom end of the positioning cylinder 4. The mounting plate 6 and the groove 15 form an embedded fit. Several positioning bolts 7 are also passed through the mounting plate 6. The several positioning bolts 7 are evenly spaced around the periphery of the positioning cylinder 4. Several internal threaded holes are correspondingly opened on the bottom wall of the groove 15. In use, the positioning cylinder 4 can be quickly installed and positioned through the groove 15. Then, the positioning bolts 7 are screwed so that their bottom ends pass through the mounting plate 6 and are threaded into the internal threaded holes, thereby fixing the positioning cylinder 4. By detachably connecting the positioning cylinder 4, the positioning cylinder 4 of the corresponding size can be replaced according to the different sizes of the support legs 93 to meet different needs.

[0038] Reference Figure 3 and Figure 4Furthermore, to further improve the applicability of the sector block 14, in this embodiment, a set of grooves 15 is provided on both the front and back sides of the sector block 14, and the distance between the two sets of grooves 15 and the central positioning tube 2 is different; that is, during use, the operator can adjust the orientation of the sector block 14 according to the distance between the welded support leg 93 and the central axis of the end cap 9, thereby adapting to the installation needs of support legs 93 with different spacings; in order to realize the use of both sides of the sector block 14, the sector... The structure of block 14 must be the same. Taking the front side as an example, the sector block 14 is provided with a clearance groove for storing the rotating plate 51. This ensures that the bottom surface of the sector block 14 is flush when it is flipped to the reverse side. In order to facilitate the workers to remove the rotating plate 51 from the clearance groove, a snap-fit ​​groove is also provided on the sector block 14, which is connected to the clearance groove. At the same time, a weight-reducing groove 16 is also provided on the sector block 14 to facilitate the workers to flip the sector block 14 or disassemble and replace it.

[0039] Reference Figure 3 and Figure 6 In this embodiment, the side positioning tube 3 is composed of a fixed tube 31, a sliding tube 32, and an abutment bolt 33. The bottom end of the fixed tube 31 is welded and fixed to the crossbar 12, and the top end of the fixed tube 31 is vertically upward. The sliding tube 32 is coaxially arranged with the fixed tube 31 and slides within the fixed tube 31 along its own axial direction. The top end of the sliding tube 32 extends out of the fixed tube 31. The abutment bolt 33 is threadedly connected to the fixed tube 31, and one end of the abutment bolt 33 passes through the fixed tube 31 and abuts against the outer wall of the sliding tube 32. The abutment bolt 33 is used to position the sliding tube 32 after sliding. That is, by using the sliding tube 32, the fixed tube 31, and the abutment bolt 33 together, the overall height of the side positioning tube 3 can be adjusted.

[0040] Reference Figure 3 and Figure 6 A connector 34 is welded to the top of the sliding tube 32. A circular positioning groove is opened on the top surface of the connector 34. The opening diameter of the positioning groove is larger than the outer diameter of the second discharge tube 92. That is, by moving the sliding tube 32 upward, the connector 34 can be moved upward until the second discharge tube 92 is embedded in the positioning groove. Then, the sliding tube 32 is tightened by screwing the abutment bolt 33, thereby realizing the connection between the second discharge tube 92 and the side positioning tube 3. Compared with the method in Embodiment 1, which requires pre-extending the length of the second discharge tube 92 and then removing the excess part after the support leg 93 is welded, the processing is simpler.

[0041] Reference Figure 3 and Figure 6To further improve the ease of use of this device, the connector 34 can be screwed onto the top of the sliding tube 32 via a threaded connection, so that the operator can replace the connector 34 with different specifications depending on the model of the second discharge tube 92 installed on the end cap 9.

[0042] The implementation principle of this application embodiment is as follows: In use, the first discharge pipe 91 and the second discharge pipe 92 are first fixed to the end cap 9 by spot welding. Then, the four support legs 93 are respectively inserted into a positioning cylinder 4 to complete the positioning of the support legs 93. Then, the end cap 9 is moved to the top of the tooling. After the first discharge pipe 91 is aligned with the center positioning tube 2, the end cap 9 is moved downward so that the first discharge pipe 91 is inserted into the center positioning tube 2, thus completing the center positioning of the end cap 9. At this time, the positioning of the support legs 93 is also completed. Then, the placement angle of the end cap 9 is adjusted and the sliding tube 32 is moved so that the connector 34 gradually approaches the second discharge pipe 92. When the bottom end of the second discharge pipe 92 is embedded in the positioning groove, the end cap 9 can be fixed. Finally, the support legs 93 are welded to the end cap 9 one by one, thus completing the connection between the support legs 93 and the end cap 9. The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A positioning fixture for welding head support legs, characterized in that: It includes a fixed plate (1), a central positioning tube (2) and a side positioning tube (3) disposed on the fixed plate (1). The central positioning tube (2) is used to connect to the first discharge tube (91) on the end cap (9). The side positioning tube (3) is used to connect to the second discharge tube (92) on the end cap (9). The fixed plate (1) is provided with a positioning cylinder (4) for inserting the support leg (93). Multiple positioning cylinders (4) are provided, and the multiple positioning cylinders (4) are evenly spaced around the central positioning tube (2).

2. The positioning fixture for welding head support legs according to claim 1, characterized in that: The fixed plate (1) includes a base plate (11), a horizontal bar (12) and a vertical bar (13) disposed on the base plate (11), and a sector block (14) disposed on the base plate (11). The horizontal bar (12) and the vertical bar (13) are arranged perpendicular to each other, and the horizontal bar (12) and the vertical bar (13) divide the base plate (11) into four placement areas. A sector block (14) can be detachably connected in any of the placement areas. Several positioning cylinders (4) are disposed on each sector block (14), and a snap-fit ​​assembly (5) is disposed between two adjacent sector blocks (14).

3. The positioning fixture for welding head support legs according to claim 2, characterized in that: The snap-fit ​​assembly (5) includes a rotating plate (51) rotating on a sector block (14), a rotating shaft (52) rotating on another sector block (14), and a limiting block (53) fixed on the rotating shaft (52). The rotating plate (51) has a clearance hole (54). The limiting block (53) passes through the clearance hole (54) and rotates to press the rotating plate (51) onto the sector block (14).

4. The positioning fixture for welding head support legs according to claim 2, characterized in that: The sector block (14) has a groove (15) and a mounting plate (6) is fixed on the positioning cylinder (4). The mounting plate (6) is fitted into the groove (15) and a positioning bolt (7) is also provided on the mounting plate (6). One end of the positioning bolt (7) passes through the mounting plate (6) and is threaded to the bottom wall of the groove (15).

5. The positioning fixture for welding head support legs according to claim 4, characterized in that: The groove (15) is provided in two sets, and the two sets of grooves (15) are respectively provided on the opposite sides of the fan-shaped block (14), and the distance between the two sets of grooves (15) and the central positioning tube (2) is different.

6. The positioning fixture for welding head support legs according to claim 1, characterized in that: An outer sleeve (8) is coaxially fixed on the central positioning tube (2), and there is a gap between the end of the outer sleeve (8) away from the fixed plate (1) and the end of the central positioning tube (2) away from the fixed plate (1).

7. The positioning fixture for welding head support legs according to claim 1, characterized in that: The side positioning tube (3) includes a fixed tube (31) fixed on a fixed plate (1), a sliding tube (32) slidably disposed on the fixed tube (31), and an abutment bolt (33) threaded on the fixed tube (31) for positioning the sliding tube (32). The sliding tube (32) is coaxially disposed with the fixed tube (31) and slides along its own axial direction. One end of the abutment bolt (33) passes through the fixed tube (31) and abuts against the side wall of the sliding tube (32). A connector (34) is provided at the end of the sliding tube (32) away from the fixed tube (31). A positioning groove for embedding the second discharge tube (92) is provided at the end of the connector (34).

8. A positioning fixture for welding head support legs according to claim 7, characterized in that: The connector (34) is detachably connected to the sliding tube (32).

9. A positioning fixture for welding head support legs according to claim 2, characterized in that: The sector block (14) is provided with a weight reduction groove (16).

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