Pin bending type tube shell parallel seam welding clamp
By designing a pin-bending type parallel seam welding fixture for the casing, the problem of pin warping caused by substrate displacement is solved, enabling efficient production and stable welding without subsequent shaping, and meeting the hermeticity requirements of high-reliability integrated package circuits.
Patent Information
- Application Number
- CN202511898464.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-16
- Publication Date
- 2026-01-23
AI Technical Summary
Existing fixtures cannot effectively prevent the substrate of the bent-pin tube shell from shifting downwards during parallel seam welding, which leads to pin warping and deformation. This requires subsequent shaping processes, increasing costs and the potential risk of microcracks at the connection interface.
A parallel seam welding fixture for lead-bending tube shells is designed. It adopts a lower fixture support and fixing mechanism and an upper fixture conformal fitting cavity. Through vertical support and horizontal limiting, it directly offsets the base displacement caused by the downward pressure of the electrode wheel, blocks the lead warping conduction path, and adopts a modular detachable design and high-temperature film surface treatment to enhance the wear resistance and stability of the fixture.
No subsequent shaping process is required, avoiding secondary stress accumulation and micro-cracks at the connection interface, improving production efficiency and electrical performance stability, meeting the hermeticity requirements of highly reliable integrated packaging circuits, and reducing operational complexity and equipment costs.
Smart Images
Figure CN121398535A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of tube shell production equipment technology, specifically relating to a pin-bending type tube shell parallel seam welding fixture. Background Technology
[0002] In the field of high-reliability integrated circuit packaging, hermetic packaging is a core technology to ensure long-term stable operation of circuits and resist interference from external environments (such as humidity, corrosive gases, and dust). Parallel seam welding has become one of the mainstream hermetic packaging processes in this field due to its advantages such as good welding sealing, small heat-affected zone, and suitability for mass production.
[0003] Parallel seam welding technology is currently widely used for encapsulating bent-pin housings. These housings consist of a substrate, a cover plate at the top of the substrate, and pins at the bottom of the substrate. The substrate is connected to the cover plate via a sealing ring at the top. Before parallel seam welding, the cover plate and sealing ring are spot-welded to preset points using the electrodes of the welding equipment to prevent relative displacement during subsequent welding. During parallel seam welding, the housing must be placed on a fixture. However, existing fixtures can only provide simple positioning of the edges or pins of the housing. The electrode wheel of the welding equipment applies a certain downward pressure during parallel seam welding to ensure tight contact between the electrode wheel and the cover plate and discharge stability. This downward pressure is transmitted through the cover plate and sealing ring to the substrate and further acts on the entire housing structure. Under the downward pressure of the electrode wheel, the ceramic substrate is prone to downward displacement; and the bent pins of the housing extend outward from the bottom of the substrate. This downward displacement of the substrate is transmitted to the pin ends through the connection between the pins and the substrate, inevitably causing the pin ends to warp upwards.
[0004] To address the aforementioned pin deformation issue, existing technologies typically employ a "post-forming" remedial solution: after parallel seam welding, an additional pin forming process is added, using specialized forming fixtures to apply mechanical force to correct the warped pins. However, this post-forming process requires additional forming equipment and occupies production workstations, extending the overall product production cycle and increasing equipment procurement, maintenance, and labor costs. Furthermore, the mechanical stress applied during forming can create secondary stress accumulation at the connection between the pin and the substrate, potentially leading to microcracks at the interface and, over long-term use, causing pin detachment, circuit breaks, and other malfunctions. Summary of the Invention
[0005] To address the technical problems existing in the prior art, the present invention provides a pin-bending type tube shell parallel seam welding fixture.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: A lead-bent type tubing parallel seam welding fixture is used to clamp lead-bent type tubing during parallel seam welding. The lead-bent type tubing includes a base, a cover plate disposed on the upper end of the base, and leads disposed on the lower end of the base. The leads include two sets of bent lead assemblies arranged at intervals on the lower end of the base and a lead frame integrally connected to the two sets of bent lead assemblies. The space between the two sets of bent lead assemblies is defined as a positioning space. The lead-bent type tubing parallel seam welding fixture includes a lower clamp body that can be detachably connected to parallel seam welding equipment, and a mating connection... The upper clamp body is located at the upper end of the lower clamp body. The upper end of the lower clamp body is provided with a support and fixing mechanism for supporting the base body, which provides vertical support for the base body and restricts the position of the base body. The upper clamp body is provided with a conforming cavity corresponding to the support and fixing mechanism. When the upper clamp body and the lower clamp body are connected, the upper end of the base body and the cover plate as a whole protrude outward from the upper opening of the conforming cavity. The bent pin assembly and the lead frame are located between the upper clamp body and the lower clamp body.
[0007] Furthermore, the support and fixing mechanism includes a support platform connected to the upper end face of the lower clamp body, and a protrusion provided on the upper end face of the support platform. The support platform protrudes towards the upper clamp body, and the protrusion can be adapted to connect with the positioning space.
[0008] Furthermore, a hard oxide film is formed on the upper end surface of the support and the outer surface of the protrusion.
[0009] Furthermore, the length of the bump is longer than the length of the positioning space.
[0010] Furthermore, the conforming cavity includes a conforming recess on the lower end face of the upper clamp body, and a through cavity extending upward from the bottom of the conforming recess to the upper end face of the upper clamp body; the conforming recess is a non-through groove formed by recessing inward from the lower end face of the upper clamp body, and its outline is adapted to the support platform; the inner diameter of the through cavity is not less than the outer diameter of the base, and the conforming recess and the through cavity are coaxially arranged.
[0011] Furthermore, the depth of the contoured recess is adapted to the height of the support. When the upper clamp body and the lower clamp body are engaged, the upper end face of the support and the bottom of the contoured recess form a receiving gap for accommodating the bent pin assembly and the lead frame.
[0012] Furthermore, the bottom surface of the groove of the contoured recess and the periphery of the cavity are both covered with a high-temperature film.
[0013] Furthermore, the lower end face of the upper clamp body is provided with a plurality of connecting posts arranged at intervals, and the upper surface of the lower clamp body is provided with a connecting part corresponding to each of the connecting posts; when the upper clamp body and the lower clamp body are engaged, each of the connecting posts is inserted into the connecting part.
[0014] Furthermore, the lower clamp body is provided with a plurality of mounting holes, which are distributed on both sides of the support and fixing mechanism, and the lower clamp body can be fixed to the worktable of the parallel seam welding equipment through the mounting holes.
[0015] In summary, the beneficial effects of this invention are as follows: 1. By using the lower clamping support and fixing mechanism to provide vertical support and horizontal limitation for the tube shell substrate, combined with the coordinated positioning of the upper clamping conformal cavity, the substrate displacement caused by the downward pressure of the electrode wheel during parallel seam welding is directly offset, completely blocking the transmission path of "substrate displacement → pin warping," eliminating the need for subsequent shaping processes. This avoids the hidden dangers of secondary stress accumulation, micro-cracks at the connection interface, and pin detachment caused by shaping, while ensuring the integrity of the tube shell structure and the stability of electrical performance, meeting the hermetic packaging requirements of high-reliability integrated circuits. 2. The clamp adopts a plug-in connection structure, requiring no complex tools for clamping, making operation convenient and efficient, reducing human error and operational barriers; the modular and detachable design (the support and protrusions can be replaced individually) supports rapid production changeover for multiple tube shell models. III. The through-cavity of the contoured fitting cavity provides ample welding space for the electrode wheel, without interfering with the parallel seam welding process; the accommodating gap formed by the matching of the bearing platform and the contoured recess precisely accommodates the bent pin assembly and lead frame, avoiding squeezing damage, slag spatter, and residual heat during welding; the slight elasticity of the high-temperature film adapts to the dimensional tolerances of the tube shell, further enhancing component protection. IV. The rigid insertion fit between the connecting post and the connecting part enhances the overall deformation resistance of the fixture, enabling it to stably withstand the downward pressure and vibration during the welding process; surface treatment processes such as hard oxide film and high-temperature film improve the fixture's wear resistance and temperature resistance, extending its service life. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the bent tube shell with pins that this fixture is to clamp.
[0017] Figure 2 This is a schematic diagram of the structure of a pin-bending type parallel seam welding fixture for tube shells provided by the present invention.
[0018] Figure 3 yes Figure 2 Exploded view.
[0019] Figure 4 yes Figure 2 A schematic diagram of a structure with a bent tube housing with pins clamped in the middle.
[0020] Figure 5 yes Figure 4 The diagram shows the structure of the lower clamp body with a pin-bent tube shell for positioning.
[0021] Figure 6 yes Figure 4 Vertical sectional view.
[0022] Figure 7 yes Figure 6 A magnified view of part A in the middle.
[0023] Figure 8 yes Figure 6 A schematic diagram of the structure of the bent tube shell without pins.
[0024] Figure 9 This is a schematic diagram of the bottom surface of the upper clamp body in this invention.
[0025] Figure 10 yes Figure 9 Vertical sectional view.
[0026] In the figure, 100-lead-bent tube shell, 110-base, 120-cover plate, 130-lead, 131-bent lead assembly, 132-lead frame, 140-positioning space, 200-lower clamp body, 210-connecting part, 220-mounting hole, 300-upper clamp body, 310-contour fitting cavity, 311-contour recess, 312-through cavity, 320-connecting post, 400-support and fixing mechanism, 410-base plate, 420-protrusion, 500-accommodating gap. Detailed Implementation
[0027] The invention will be further illustrated below with reference to specific figures.
[0028] Please see Figure 1 The present invention provides a pin-bent type tube shell parallel seam welding fixture for clamping a pin-bent type tube shell 100 during parallel seam welding. The pin-bent type tube shell 100 includes a base 110, a cover plate 120 disposed at the upper end of the base 110, and pins 130 disposed at the lower end of the base 110. The pins 130 include two sets of bent pin assemblies 131 arranged at intervals at the lower end of the base 110 and a lead frame 132 integrally connected to the two sets of bent pin assemblies 131. The two sets of bent pin assemblies 131 are symmetrically distributed along the central axis of the lower end surface of the base 110, and the regular space naturally formed between the two sets of assemblies is defined as the positioning space 140 of the tube shell.
[0029] Please see Figure 2 and Figure 3The pin-bending type parallel seam welding fixture includes a lower fixture body 200 detachably connectable to parallel seam welding equipment, and an upper fixture body 300 matingly connected to the upper end of the lower fixture body 200. The upper end of the lower fixture body 200 has a support and fixing mechanism 400 for supporting a base 110, providing vertical support and restricting the position of the base 110. The upper fixture body 300 has a contoured mating cavity 310 corresponding to the support and fixing mechanism 400. When the upper fixture body 300 and the lower fixture body 200 are mated and connected, please refer to... Figure 4 The upper end of the substrate 110 and the cover plate 120 protrude outward from the upper opening of the conformal fitting cavity 310, while the bent pin 130 assembly and the lead frame 132 are located between the upper clamp body 300 and the lower clamp body 200. The support and fixing mechanism 400 of the lower clamp body 200 provides vertical support and position limitation for the tube shell substrate 110, directly counteracting the downward displacement tendency of the substrate 110 caused by the downward pressure of the electrode wheel, blocking the transmission path of displacement to the end of the pin 130, and preventing the pin 130 from warping and deforming from the source of the welding process. This reduces manual shaping operations, simplifies the production process, significantly shortens the overall product production cycle, and improves batch production efficiency.
[0030] The lower clamp body 200 has several mounting holes 220 distributed on both sides of the support and fixing mechanism 400. By installing bolts in the mounting holes 220, the lower clamp body 200 is fixed to the worktable of the parallel seam welding equipment. The lower clamp body 200 is rigidly fixed to the worktable of the parallel seam welding equipment by the bolts in the mounting holes 220, which avoids displacement, shaking or vibration of the clamp during the welding process (electrode wheel rolling, discharge impact, downward pressure). It reduces problems such as contact deviation between the electrode wheel and the cover plate 120 and welding trajectory deviation caused by clamp displacement, ensuring the sealing performance, weld consistency and welding quality stability of the parallel seam welding, and adapting to the precision welding requirements of high-reliability integrated packaged circuits.
[0031] Please see Figure 3 and Figure 5The support and fixing mechanism 400 includes a platform 410 connected to the upper end face of the lower clamp body 200, and a protrusion 420 disposed on the upper end face of the platform 410. The platform 410 protrudes towards the upper clamp body 300. The protrusion 420 can be adapted to the positioning space 140. The protrusion 420 is adapted to the positioning space 140 between the two sets of bent pin assemblies 131 of the tube shell, forming a surface-fitting positioning. At the same time, the platform 410 provides a stable vertical support surface for the tube shell base 110. The protruding structure of the platform 410 increases the contact support area with the base 110. After the protrusion 420 is embedded in the positioning space 140, it forms a mechanical structure of "intermediate support - two-sided limiting", which greatly improves the support stability of the base 110. The support and fixing mechanism 400 ensures the stability of the tube shell positioning and avoids squeezing or scratching damage to the bent pin assembly 131 and lead frame 132. At the same time, it does not obstruct the cover plate 120 and sealing ring at the upper end of the base 110. It is fully compatible with the welding operation space of the electrode wheel of the parallel seam welding equipment and ensures the normal implementation of the welding process.
[0032] A hard oxide film is formed on the upper end surface of the bearing 410 and the outer surface of the protrusion 420. The hard oxide film is preferably an aluminum-based hard anodized film, but a diamond-like coating can also be used. The hard oxide film is used to improve the support and fit between the bearing 410 and the substrate 110, as well as the fit stability between the protrusion 420 and the positioning space 140, and can also enhance the wear resistance of the bearing 410 and the protrusion 420.
[0033] The support 410 can be integrally formed with the lower clamp body 200. This integrated structure avoids potential positional shifts and level deviations of the support 410 during assembly, ensuring the fitting accuracy between the protrusion 420 and the tube housing positioning space 140. In another embodiment, the support 410 is bolted to the lower clamp body 200, allowing for individual replacement, adjustment, or repair, thus providing greater flexibility.
[0034] The protrusion 420 is detachably connected to the bearing 410. The protrusion 420 can be connected to the bearing 410 via bolts or magnetic blocks. As a key component that directly adapts to the positioning space 140 of the tube shell, the protrusion 420 can be individually designed and manufactured according to the size and shape of the positioning space 140 of different tube shell models. The detachable connection enables quick replacement. The protrusion 420 is a core component that directly contacts the tube shell and bears clamping friction and stress. It is prone to wear, deformation, or peeling of the hard oxide film. The detachable design supports individual maintenance or replacement. The length of the protrusion 420 is preferably longer than the length of the positioning space 140. By making the length of the protrusion 420 slightly longer than the length of the tube shell positioning space 140, the two ends of the protrusion 420 form a visible exposed section during assembly, which helps the staff to intuitively judge whether the fitting position of the tube shell and the protrusion 420 is accurate, quickly identify clamping deviations, improve clamping accuracy and efficiency from the operation level, reduce the risk of human operation error, and the longer contact length increases the force contact area between the protrusion 420 and the positioning space 140, avoiding local stress concentration.
[0035] The contour-following cavity 310 includes a contour-following recess 311 located on the lower end face of the upper clamp body 300, and a through cavity 312 extending upward from the bottom of the contour-following recess 311 to the upper end face of the upper clamp body 300. The contour-following recess 311 is a non-through groove formed by recessing inward from the lower end face of the upper clamp body 300, and its contour is adapted to the support 410. The inner diameter of the through cavity 312 is not less than the outer diameter of the base 110, and the contour-following recess 311 and the through cavity 312 are coaxially arranged. During assembly, the contour-following recess 311 and the support 410 form a fitting fit, automatically calibrating the relative positions of the upper and lower clamps, ensuring that the through cavity 312 is coaxial with the lower clamp protrusion 420 and the tube base 110, and avoiding tube clamping skew caused by misalignment of the upper and lower clamps. The through cavity 312 provides ample operating space for the electrode wheel of the parallel seam welding equipment, ensuring that the electrode wheel can freely contact the welding area between the cover plate 120 and the sealing ring without obstructing the weld trajectory, thus ensuring the smooth implementation of the parallel seam welding process.
[0036] The depth of the contoured recess 311 is adapted to the height of the support 410. When the upper clamp body 300 and the lower clamp body 200 are engaged, please refer to [the relevant documentation]. Figure 6 , Figure 7 and Figure 8 The upper end face of the base 410 and the bottom of the contoured recess 311 form a receiving gap 500 for accommodating the bent lead 130 assembly and the lead frame 132. The gap height prevents the bent lead 130 or lead frame 132 from being squeezed or damaged when the upper clamp presses down, and also avoids the lead 130 from shaking during the welding process due to excessive gap. For the bent structure of the bent lead 130, the receiving gap 500 provides sufficient space to avoid interfering with the bending shape of the lead 130, ensuring that the overall structure of the casing is not affected by clamping.
[0037] The bottom surface of the groove of the contoured recess 311 and the periphery of the through cavity 312 are covered with a high-temperature film. The high-temperature film can be a polyimide high-temperature film. The slight elasticity of the high-temperature film can adapt to the small dimensional tolerances of the tube shell substrate 110 and the pin 130, improve the adhesion between the film layer and the tube shell, and avoid scratches caused by hard contact.
[0038] Please see Figure 9 and Figure 10 The upper clamp body 300 has a plurality of connecting posts 320 protruding from its bottom surface at intervals, and the lower clamp body 200 has a connecting part 210 corresponding to each connecting post 320. The connecting part 210 can be a through hole penetrating the lower clamp body 200, or a groove structure recessed from the upper end of the lower clamp body 200 toward the direction away from the upper clamp body 300. When the upper clamp body 300 and the lower clamp body 200 are engaged, each connecting post 320 is inserted into the corresponding connecting part 210. Through the insertion and engagement structure of the connecting posts 320 and the corresponding connecting parts 210, the upper clamp body 300 and the lower clamp body 200 can be quickly positioned and stably connected without repeated manual adjustment and calibration. During the insertion process, the connecting posts 320 can guide the upper clamp body 300 to quickly fall into the correct position. The one-to-one insertion of the connecting posts 320 and the connecting parts 210 forms a multi-point guiding and positioning structure, which automatically calibrates the relative position of the upper and lower clamps.
[0039] The usage process of this parallel seam welding fixture is as follows: The lower fixture body 200 is rigidly fixed to the worktable of the parallel seam welding equipment using bolts through the mounting holes 220 on both sides, completing the precise docking of the fixture and the equipment. The lower end face of the base 110 of the bent tube shell 100 with pins 130 is attached to the upper end face of the support 410 of the lower fixture support and fixing mechanism 400, so that the protrusion 420 on the top of the support 410 is embedded in the positioning space 140 between the two sets of bent pins 130 assemblies of the tube shell (the extra-long design of the protrusion 420 allows for visual confirmation of the degree of engagement through the exposed sections at both ends), achieving horizontal limiting and vertical support for the tube shell. Align the connecting post 320 on the lower end face of the upper clamp body 300 with the corresponding connecting part 210 of the lower clamp body 200, and press the upper clamp body 300 downwards to insert the connecting post 320 into place. At the same time, the contouring recess 311 of the upper clamp and the base 410 of the lower clamp form a fitting fit, automatically calibrating the coaxiality of the upper and lower clamps. After the upper and lower clamps are fitted, the upper end of the base 110 and the cover plate 120 are exposed from the upper end opening of the through cavity 312 of the contouring fitting cavity 310 (without interfering with the welding operation). The bent pin 130 assembly and the lead frame 132 are housed in the receiving gap 500 formed by the upper end face of the base 410 and the bottom of the contouring recess 311 (without squeezing or shaking), completing the entire process of clamping the tube shell, and parallel seam welding can be started.
[0040] This parallel seam welding fixture: 1. The lower clamping support and fixing mechanism 400 provides vertical support and horizontal limitation for the tube housing base 110. Combined with the coordinated positioning of the upper clamping conformal fitting cavity 310, it directly counteracts the displacement of the base 110 caused by the downward pressure of the electrode wheel during parallel seam welding, completely blocking the transmission path of "base 110 displacement → pin 130 warping," eliminating the need for subsequent shaping processes. This avoids the risks of secondary stress accumulation, micro-cracks at the connection interface, and pin 130 detachment caused by shaping, while ensuring the structural integrity and electrical performance stability of the tube housing, meeting the hermetic packaging requirements of high-reliability integrated circuits. 2. The fixture adopts a plug-in connection structure, requiring no complex tools for clamping, making operation convenient and efficient, reducing human error and operational barriers; the modular and detachable design (the support 410 and the bump 420 can be replaced individually) supports rapid production changeover for multiple tube housing models. III. The through-cavity portion 312 of the contoured mating cavity 310 provides ample welding space for the electrode wheel, without interfering with the parallel seam welding process; the accommodating gap 500 formed by the fit between the support 410 and the contoured recess 311 precisely accommodates the bent pin 130 assembly and the lead frame 132, avoiding squeezing damage, slag spatter, and residual heat during welding; the slight elasticity of the high-temperature film adapts to the dimensional tolerances of the tube shell, further enhancing component protection. IV. The rigid insertion fit between the connecting post 320 and the connecting portion 210 enhances the overall deformation resistance of the fixture, enabling it to stably withstand the downward pressure and vibration during the welding process; surface treatment processes such as hard oxide film and high-temperature film improve the wear resistance and temperature resistance of the fixture, extending its service life.
[0041] The above are merely embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structures made using the contents of the present invention specification and drawings, whether directly or indirectly applied to other related technical fields, are similarly within the patent protection scope of the present invention.
Claims
1. A lead-bent type tube shell parallel seam welding fixture for clamping lead-bent type tube shells during parallel seam welding, the lead-bent type tube shell comprising a base, a cover plate disposed at the upper end of the base, and leads disposed at the lower end of the base, the leads comprising two sets of bent lead assemblies arranged at intervals at the lower end of the base and a lead frame integrally connected to the two sets of bent lead assemblies, the space between the two sets of bent lead assemblies being defined as a positioning space, characterized in that: The device includes a lower clamp body that can be detachably connected to a parallel seam welding device, and an upper clamp body that is fitted to the upper end of the lower clamp body. The upper end of the lower clamp body is provided with a support and fixing mechanism for supporting the base body, forming vertical support for the base body and restricting the position of the base body. The upper clamp body is provided with a conformal fitting cavity corresponding to the support and fixing mechanism. When the upper clamp body and the lower clamp body are fitted together, the upper end of the base body and the cover plate as a whole protrude outward from the upper opening of the conformal fitting cavity, while the bent pin assembly and the lead frame are located between the upper clamp body and the lower clamp body.
2. The pin-bending type tube shell parallel seam welding fixture according to claim 1, characterized in that: The support and fixing mechanism includes a support platform connected to the upper end face of the lower clamp body, and a protrusion provided on the upper end face of the support platform. The support platform protrudes towards the upper clamp body, and the protrusion can be adapted to connect with the positioning space.
3. The pin-bending type parallel seam welding fixture for tube shells according to claim 2, characterized in that: A hard oxide film is formed on the upper end surface of the support and the outer surface of the protrusion.
4. The pin-bending type parallel seam welding fixture for tubing shells according to claim 2, characterized in that: The length of the bump is longer than the length of the positioning space.
5. The pin-bending type tube shell parallel seam welding fixture according to claim 2, characterized in that: The conformal fitting cavity includes a conformal recess on the lower end face of the upper clamp body, and a through cavity extending upward from the bottom of the conformal recess to the upper end face of the upper clamp body; the conformal recess is a non-through groove formed by recessing inward from the lower end face of the upper clamp body, and its outline is adapted to the support platform; the inner diameter of the through cavity is not less than the outer diameter of the base, and the conformal recess and the through cavity are coaxially arranged.
6. The pin-bending type parallel seam welding fixture for tubing shells according to claim 5, characterized in that: The depth of the contoured recess is adapted to the height of the support. When the upper clamp body and the lower clamp body are engaged, the upper end face of the support and the bottom of the contoured recess form a receiving gap for accommodating the bent pin assembly and the lead frame.
7. The pin-bending type tube shell parallel seam welding fixture according to claim 5, characterized in that: The bottom surface of the groove of the contoured recess and the periphery of the cavity are both covered with a high-temperature film.
8. The pin-bending type tube shell parallel seam welding fixture according to claim 1, characterized in that: The lower end face of the upper clamp body is provided with a plurality of connecting posts arranged at intervals, and the upper surface of the lower clamp body is provided with a connecting part corresponding to each of the connecting posts; when the upper clamp body and the lower clamp body are engaged, each of the connecting posts is inserted into the connecting part.
9. The pin-bending type parallel seam welding fixture for tube shells according to any one of claims 1-8, wherein the lower fixture body is provided with a plurality of mounting holes, the mounting holes being distributed on both sides of the support and fixing mechanism, and the lower fixture body can be fixed to the worktable of the parallel seam welding equipment through the mounting holes.