Elbow pipe and elbow assembling device and workstation
Through the symmetric clamping assembly and work station designed with floating jaws, the versatility and flexibility of bent pipes on different diameters and contours is solved, and the efficient, precise butt and automatic loading of bent pipes with straight pipes is achieved, thereby improving assembly quality and efficiency.
Patent Information
- Application Number
- CN202422246279.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-12
- Publication Date
- 2025-08-12
- Estimated Expiration
- 2034-09-12
AI Technical Summary
The existing pipeline assembly devices have poor versatility and flexibility for bent pipes of different diameters and contoured surfaces, resulting in inadequate assembly quality and efficiency, and it is difficult for traditional manual operations to ensure accuracy and consistency.
The clamping assembly and floating clamping jaw design are adopted, combined with the Y-direction clamping drive device and the three-jaw clamping assembly, to achieve efficient and precise docking of the bent pipe and the straight pipe, and to achieve automatic loading through the loading robot arm and special fixture.
It improves the automation and consistency of pipeline assembly, enhances the versatility and flexibility of the device, ensures the stability and accuracy of the bend during the assembly process, and reduces the difficulty and strength of manual operation.
Smart Images
Figure CN223210798U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of pipeline assembly, in particular to a pipe elbow assembly device and a workstation. Background Art
[0002] The docking and assembly of curved and straight pipes is a critical step in the installation and manufacturing of piping systems. Traditional assembly methods rely primarily on manual labor, which is not only inefficient but also susceptible to human factors, making it difficult to ensure assembly accuracy and consistency. Especially in large-scale assembly line operations, traditional manual assembly methods can no longer meet the requirements of efficient and precise production.
[0003] While some pipe assembly devices are currently available on the market, most are designed for specific pipe sizes and shapes, resulting in limited versatility and flexibility. Traditional devices often struggle to achieve stable and precise clamping of curved pipes of varying diameters and contours, compromising assembly quality and efficiency. Furthermore, traditional devices may lack sufficient support during the clamping process, causing the pipe to shift or deform during assembly, further reducing assembly accuracy. Utility Model Content
[0004] The purpose of this utility model is to address the problems existing in the prior art and provide a pipe elbow assembly device and workstation. By adopting a symmetrically arranged clamping assembly and floating jaw design, it can adapt to pipes with different diameters and contours, enhancing the versatility and flexibility of the device, achieving efficient and precise docking of bent and straight pipes, and improving the automation and consistency of pipe assembly.
[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:
[0006] A curved pipe elbow assembly device comprises a base, a fixed base and a movable base, the fixed base being fixedly connected to the base, and the movable base being slidably connected to the base along the X direction; the fixed base being connected to a curved pipe clamping mechanism, and the movable base being connected to a straight pipe clamping mechanism; the curved pipe clamping mechanism comprises a first clamping assembly and a second clamping assembly symmetrically arranged, and a Y-direction clamping drive device; the first clamping assembly comprises a first clamping frame, and a first floating clamping jaw connected to the first clamping frame; the second clamping assembly comprises a second clamping frame, and a second floating clamping jaw connected to the second clamping frame; the first clamping frame and the second clamping frame are respectively slidably connected to one side of the fixed base along the Y direction, and the Y-direction clamping drive device is used to drive the first clamping frame and the second clamping frame to approach and move away from each other to achieve curved pipe clamping; the straight pipe clamping mechanism comprises a three-claw clamping assembly 1 connected to one side of the movable base, which is used to radially clamp the outer wall of the straight pipe.
[0007] The first floating jaw and the second floating jaw each include a clamp housing, one side of the clamp housing extending outwardly and provided with an ejector pin array, the ejector pin array consisting of a plurality of ejector pins evenly spaced apart, the clamp housing provided with an air cavity connected to an external air source, the ejector pins being connected to the clamp housing and to the air cavity via a spring.
[0008] The first clamping frame connects the two first floating jaws, and the second clamping frame connects the two second floating jaws, wherein one pair of the first floating jaws and the second floating jaws are used to clamp the outer wall of the first end of the bent pipe, and the other pair of the first floating jaws and the second floating jaws are used to clamp the outer wall of the second end of the bent pipe, so that the bent pipe is in a sideways posture.
[0009] One side wall of the fixed seat is provided with two Y-axis slide rails, and the first clamping frame and the second clamping frame are respectively slidably connected to the Y-axis slide rails; the Y-axis clamping drive device includes a Y-axis screw rod, a shaft sleeve, a pulley assembly, and a driving motor; the Y-axis screw rod is rotatably connected to the fixed seat through the shaft sleeve, and the Y-axis screw rod is provided with two sections of threads with opposite rotation directions; the first clamping frame and the second clamping frame are respectively provided with threaded holes, and are respectively connected to the two sections of the Y-axis screw rod; one end of the Y-axis screw rod is connected to the pulley assembly, and the driving motor drives the pulley assembly to drive the Y-axis screw rod to rotate, thereby realizing the approach and distance between the first clamping frame and the second clamping frame.
[0010] A bend elbow assembly workstation includes the above-mentioned bend elbow assembly device; it also includes a loading robot arm, and a bend pipe loading clamp or a straight pipe loading clamp connected to the end of the loading robot arm; the bend pipe loading clamp is used to clamp the bend pipe, and under the drive of the loading robot arm, the bend pipe is docked with the bend pipe clamping mechanism; the straight pipe loading clamp is used to clamp the straight pipe, and under the drive of the loading robot arm, the straight pipe is docked with the straight pipe clamping mechanism.
[0011] The bent pipe loading fixture includes a fixture mounting base connected to the end of the loading robot arm, and a three-jaw clamping component 2 and a three-jaw clamping component 3 respectively connected to the fixture mounting base; the three-jaw clamping component 2 is used to clamp the outer wall of the first end of the bent pipe from the radial direction; the three-jaw clamping component 3 includes the first clamping cylinder, the second clamping cylinder and the third clamping cylinder respectively connected to the fixture mounting base, the first clamping cylinder extends into the inner hole of the second end of the bent pipe, and is used to push the inner wall of the inner hole of the second end of the bent pipe, the second clamping cylinder and the third clamping cylinder are symmetrically arranged on both sides of the first clamping cylinder, and are respectively used to push the outer wall of the second end of the bent pipe.
[0012] Compared with the prior art, the beneficial effects of the present invention are:
[0013] 1. This elbow assembly device and workstation achieves efficient and precise docking of elbows and straight pipes through precise mechanical design and automated control, significantly improving assembly accuracy and consistency.
[0014] 2. The floating jaw design in the device can adapt to bends of different diameters and contour surfaces, allowing the device to clamp pipes of various specifications and shapes, enhancing the versatility and flexibility of the device and meeting the assembly needs of different production scenarios;
[0015] 3. The pin array design in the floating clamp can closely contact the outer wall of the elbow, providing not only Y-axis clamping force but also Z-axis support force, which enhances the stability and accuracy of clamping and ensures that the elbow will not deflect or deform during assembly, thus ensuring the quality of assembly.
[0016] 4. By introducing a loading robot arm and a dedicated loading fixture, the automatic loading and docking of curved and straight pipes is realized, which reduces the difficulty and intensity of manual operation and improves the efficiency and accuracy of assembly. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0018] Figure 1 This is a schematic diagram of the overall structure of an assembly device in one embodiment of the present application;
[0019] Figure 2 This is a schematic diagram of the overall structure of an assembly device in one embodiment of the present application;
[0020] Figure 3 This is a schematic diagram of the disassembled structure of an assembly device in one embodiment of the present application;
[0021] Figure 4 This is a schematic diagram of the disassembled structure of the elbow clamping mechanism in one embodiment of the present application;
[0022] Figure 5 This is a schematic diagram of the overall structure of a workstation in one embodiment of the present application;
[0023] Figure 6 This is a schematic structural diagram of a bent pipe loading fixture in one embodiment of the present application;
[0024] Figure 7 This is a schematic diagram of the disassembled structure of the elbow feeding fixture in one embodiment of the present application;
[0025] In the figure: 1. Base; 2. Fixed seat; 3. Movable seat; 4. First clamping frame; 5. First floating clamping jaw; 6. Second clamping frame; 7. Second floating clamping jaw; 8. Three-jaw clamping assembly one; 9. Y-axis screw; 10. Pulley assembly; 11. Drive motor; 12. Loading robot arm; 13. Bend pipe loading fixture; 15. Fixture mounting seat; 16. Three-jaw clamping assembly two; 17. Three-jaw clamping assembly three; 18. First clamping cylinder; 19. Second clamping cylinder; 20. Third clamping cylinder. DETAILED DESCRIPTION
[0026] The following is a clear and complete description of the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.
[0027] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the utility model product is typically placed when in use. These terms are intended solely to facilitate the description of this utility model and simplify the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third," etc., are used solely to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0028] Furthermore, terms such as "horizontal" and "vertical" do not necessarily mean that a component must be absolutely horizontal or overhanging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted.
[0029] It should also be noted that, in the description of this utility model, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.
[0030] The first aspect of this application is Figures 1 to 4As shown, a curved pipe elbow assembly device is provided, including a base 1, a fixed base 2 and a movable base 3, the fixed base 2 is fixedly connected to the base 1, and the movable base 3 is slidably connected to the base 1 along the X direction; the fixed base 2 is connected to the curved pipe clamping mechanism, and the movable base 3 is connected to the straight pipe clamping mechanism; the curved pipe clamping mechanism includes a first clamping component and a second clamping component symmetrically arranged, and a Y-direction clamping drive device; the first clamping component includes a first clamping frame 4, and a first floating clamping jaw 5 connected to the first clamping frame 4; the second clamping assembly includes a second clamping frame 6, and a second floating clamping jaw 7 connected to the second clamping frame 6; the first clamping frame 4 and the second clamping frame 6 are respectively connected to one side of the fixed base 2 along the Y direction, and the Y-direction clamping drive device is used to drive the first clamping frame 4 and the second clamping frame 6 to approach and move away from each other to achieve curved pipe clamping; the straight pipe clamping mechanism includes a three-claw clamping assembly 8 connected to one side of the movable seat, which is used to radially clamp the outer wall of the straight pipe.
[0031] Specifically, the fixed seat 2 is connected to the bent pipe clamping mechanism, and the movable seat 3 is connected to the straight pipe clamping mechanism, and the two clamp the bent pipe and the straight pipe respectively. The bent pipe clamping mechanism adopts a symmetrically arranged first clamping assembly and a second clamping assembly, which are driven by the Y-direction clamping drive device to slide along the Y-direction to achieve stable clamping of the bent pipe. The straight pipe clamping mechanism radially clamps the outer wall of the straight pipe through a three-claw clamping assembly to ensure the stability of the straight pipe during the assembly process. When in use, first place the bent pipe and the straight pipe in the corresponding clamping mechanism and clamp them respectively, then align the axis of the bent pipe with the straight pipe through the preset position, and finally control the movable seat to move along the X-direction to achieve precise docking of the bent pipe and the straight pipe.
[0032] The application of this pipe elbow assembly device realizes the efficient and precise docking of bent pipes and straight pipes, significantly reduces the manual operations in the traditional assembly process, improves the degree of automation of assembly, ensures the consistency of bent pipe assembly, and greatly improves the efficiency of assembly line operations.
[0033] The floating jaw design in the device can adapt to bends with different diameters and contour surfaces, enhancing the versatility and flexibility of the device and ensuring the stability of the bend clamping.
[0034] In some embodiments, as Figure 3 and Figure 4 As shown, the first floating jaw 5 and the second floating jaw 7 both include a fixture housing, one side of which is provided with an ejector pin array extending outward. The ejector pin array is composed of a plurality of ejector pins evenly spaced apart. The fixture housing is provided with an air cavity connected to an external air source. The ejector pins are connected to the fixture housing and to the air cavity via a spring.
[0035] Specifically, the loading robot first places the bent pipe between the two clamping assemblies, and then the Y-axis clamping drive device drives the first clamping frame 4 and the second clamping frame 6 to approach each other. After the ejector array contacts the outer wall of the bent pipe, the ejector retracts into the fixture housing along the surface contour of the contact surface, achieving close contact between the ejector array and the outer wall of the bent pipe. Then, the external air source inflates the air cavity, causing the ejector arrays on both sides of the bent pipe to generate a pushing force respectively to achieve clamping. Since the ejector array is in close contact along the contour of the outer wall of the bent pipe, it not only has a Y-axis clamping force on the bent pipe, but also a Z-axis supporting force, which enhances the stability and accuracy of the clamping. Due to the flexibility and adaptability of the ejector array, the device can clamp bent pipes of different diameters and shapes, improving the versatility of the device. By controlling the clamping and release of the ejector by air pressure, fast and efficient clamping of the bent pipe is achieved.
[0036] Preferably, the first floating jaw 5 and the second floating jaw 7 adopt the pneumatic series pneumatic A-type clamps of Suzhou Chaiqi Industrial Intelligence Co., Ltd.
[0037] In some embodiments, as Figure 4 As shown, the first clamping frame 4 is connected to two first floating jaws 5, and the second clamping frame 6 is connected to two second floating jaws 7, wherein one pair of first floating jaws 5 and second floating jaws 7 are used to clamp the outer wall of the first end of the bent pipe, and the other pair of first floating jaws 5 and second floating jaws 7 are used to clamp the outer wall of the second end of the bent pipe, so that the bent pipe is in a side-standing posture.
[0038] Specifically, by using two pairs of floating clamps to simultaneously clamp the two ends of the bent pipe, it is ensured that the bent pipe is in a sideways posture during the assembly process, which is more convenient for docking with the straight pipe, thereby improving the efficiency and success rate of assembly.
[0039] In some embodiments, as Figure 4 As shown, one side wall of the fixed seat 2 is provided with two Y-direction slide rails, and the first clamping frame 4 and the second clamping frame 6 are respectively slidably connected to the Y-direction slide rails; the Y-direction clamping drive device includes a Y-direction screw rod 9, a shaft sleeve, a pulley assembly 10, and a drive motor 11. The Y-direction screw rod 9 is rotatably connected to the fixed seat 2 through the shaft sleeve, and the Y-direction screw rod 9 is provided with two sections of threads with opposite rotation directions. The first clamping frame 4 and the second clamping frame 6 are respectively provided with threaded holes, and are respectively connected to the two sections of the Y-direction screw rod 9; one end of the Y-direction screw rod 9 is connected to the pulley assembly 10, and the drive motor 11 drives the pulley assembly 10 to drive the Y-direction screw rod 9 to rotate, thereby realizing the approach and distance between the first clamping frame and the second clamping frame.
[0040] Specifically, when the drive motor is activated, it rotates the Y-axis screw via the pulley assembly. Because the Y-axis screw has two sections of threads with opposite rotational directions, as the screw rotates, the first clamping frame 4 and the second clamping frame 6 slide simultaneously but in opposite directions along the Y-axis slide rail, moving closer to or farther from each other, thereby clamping or releasing the bent pipe. The guidance of the Y-axis slide rail ensures the stability and accuracy of the first and second clamping frames during the sliding process. The design of the two sections of threads with opposite rotational directions on the Y-axis screw enables the two clamping frames to move simultaneously but in opposite directions, ensuring that the bent pipe is subjected to uniform and symmetrical clamping force during the clamping process.
[0041] The second aspect of this application is Figures 5 to 7 As shown, a bend elbow assembly workstation is provided, including the above-mentioned bend elbow assembly device; it also includes a loading robot arm 12, and a bend pipe loading fixture 13 or a straight pipe loading fixture connected to the end of the loading robot arm 12; the bend pipe loading fixture 13 is used to clamp the bend pipe, and connect the bend pipe with the bend pipe clamping mechanism under the drive of the loading robot arm 12; the straight pipe loading fixture is used to clamp the straight pipe, and connect the straight pipe with the straight pipe clamping mechanism under the drive of the loading robot arm 12.
[0042] Specifically, during operation, the loading robot arm 12 is used to transport curved and straight pipes from the loading area to the assembly area. When a curved pipe is required, the curved pipe loading fixture grips it and, guided by the loading robot arm, precisely connects it to the curved pipe clamping mechanism. Similarly, when a straight pipe is required, the straight pipe loading fixture grips it and, guided by the loading robot arm, precisely connects it to the straight pipe clamping mechanism, preparing for subsequent assembly and docking.
[0043] The introduction of a loading robot 12 and dedicated loading fixtures enables automated loading and docking of curved and straight pipes, improving assembly efficiency and accuracy while reducing the difficulty and intensity of manual operation. The high precision and flexibility of the loading robot ensures accuracy and consistency during the docking process, improving assembly quality and stability.
[0044] In some embodiments, as Figure 6 and Figure 7As shown, the bent pipe loading fixture 13 includes a fixture mounting base 15 connected to the end of the loading robot arm 12, and a three-jaw clamping component 2 16 and a three-jaw clamping component 3 17 respectively connected to the fixture mounting base 15; the three-jaw clamping component 2 16 is used to clamp the outer wall of the first end of the bent pipe from the radial direction; the three-jaw clamping component 3 17 includes a first clamping cylinder 18, a second clamping cylinder 19 and a third clamping cylinder 20 respectively connected to the fixture mounting base 15, the first clamping cylinder 18 extends into the inner hole of the second end of the bent pipe, and is used to push the inner wall of the inner hole of the second end of the bent pipe, the second clamping cylinder 19 and the third clamping cylinder 20 are symmetrically arranged on both sides of the first clamping cylinder 18, and are respectively used to push the outer wall of the second end of the bent pipe.
[0045] Specifically, through the cooperation of the three-jaw clamping assembly 2 16 and the three-jaw clamping assembly 3 17, all-round clamping of the bent pipe is achieved, ensuring the stability and accuracy of the bent pipe during the loading and docking process.
[0046] When the clamping operation begins, the three clamping cylinders will start at the same time, and the first clamping cylinder 18 will apply force outward, that is, its piston rod will extend to push the inner wall of the inner hole at the second end of the bent pipe to form a first force point. At the same time, the piston rods of the second clamping cylinder 19 and the third clamping cylinder 20 will also extend to push the outer wall of the second end of the bent pipe respectively. Since these two cylinders are symmetrically arranged on both sides of the first clamping cylinder 18, the thrust they generate will be evenly distributed on both sides of the first force point, together forming a three-point clamping of the bent pipe. Under the joint action of these three force points, the side wall of the second end of the bent pipe is firmly clamped, maintaining the stability of the docking.
[0047] It should be noted that the three-jaw clamping assembly 1 8 and the three-jaw clamping assembly 3 17 are existing technologies and are widely used in the field of industrial automation. They are usually composed of three movable jaws evenly distributed on the circumference. When the workpiece needs to be clamped, the three jaws are moved inward at the same time through a driving mechanism (such as air pressure, hydraulic pressure or motor) to achieve clamping.
[0048] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A pipe elbow assembly device, characterized in that: It comprises a base (1), a fixed base (2) and a movable base (3), wherein the fixed base (2) is fixedly connected to the base (1), and the movable base (3) is slidably connected to the base (1) along the X direction; the fixed base (2) is connected to a bent pipe clamping mechanism, and the movable base (3) is connected to a straight pipe clamping mechanism; The bent pipe clamping mechanism includes a first clamping assembly and a second clamping assembly that are symmetrically arranged, and a Y-axis clamping drive device; The first clamping assembly includes a first clamping frame (4) and a first floating clamping claw (5) connected to the first clamping frame (4); the second clamping assembly includes a second clamping frame (6) and a second floating clamping claw (7) connected to the second clamping frame (6); the first clamping frame (4) and the second clamping frame (6) are respectively connected to one side of the fixed seat (2) in a sliding manner along the Y direction, and the Y-direction clamping drive device is used to drive the first clamping frame (4) and the second clamping frame (6) to move closer to and away from each other to achieve bending pipe clamping; The straight tube clamping mechanism comprises a three-claw clamping assembly (8) connected to one side of the movable seat, which is used for radially clamping the outer wall of the straight tube.
2. The elbow assembly device according to claim 1, characterized in that: The first floating clamp (5) and the second floating clamp (7) both comprise a clamp housing, one side of the clamp housing being provided with an ejector pin array extending outward, the ejector pin array being composed of a plurality of ejector pins evenly spaced and distributed, the clamp housing being provided with an air cavity connected to an external air source, the ejector pin being connected to the clamp housing and to the air cavity via a spring.
3. The elbow assembly device according to claim 2, characterized in that: The first clamping frame (4) is connected to the two first floating clamping jaws (5), and the second clamping frame (6) is connected to the two second floating clamping jaws (7), wherein one pair of the first floating clamping jaws (5) and the second floating clamping jaws (7) are used to clamp the outer wall of the first end of the bent pipe, and the other pair of the first floating clamping jaws (5) and the second floating clamping jaws (7) are used to clamp the outer wall of the second end of the bent pipe, so that the bent pipe is in a side-standing posture.
4. The elbow assembly device according to claim 1, characterized in that: One side wall of the fixing seat (2) is provided with two Y-direction slide rails, and the first clamping frame (4) and the second clamping frame (6) are respectively slidably connected to the Y-direction slide rails; The Y-axis clamping drive device comprises a Y-axis screw rod (9), a shaft sleeve, a pulley assembly (10), and a driving motor (11). The Y-axis screw rod (9) is rotatably connected to the fixed seat (2) through the shaft sleeve. The Y-axis screw rod (9) is provided with two sections of threads with opposite rotation directions. The first clamping frame (4) and the second clamping frame (6) are respectively provided with threaded holes and are respectively connected to the two sections of the threads of the Y-axis screw rod (9). One end of the Y-axis screw rod (9) is connected to the pulley assembly (10). The driving motor (11) drives the pulley assembly (10) to drive the Y-axis screw rod (9) to rotate, thereby realizing the approach and separation of the first clamping frame and the second clamping frame.
5. A pipe elbow assembly workstation, characterized in that: The invention comprises the bend elbow assembly device according to any one of claims 1 to 4; and further comprises a feeding robot arm (12), and a bend pipe feeding fixture (13) or a straight pipe feeding fixture connected to the end of the feeding robot arm (12); the bend pipe feeding fixture (13) is used to clamp the bend pipe, and dock the bend pipe with the bend pipe clamping mechanism under the drive of the feeding robot arm (12); the straight pipe feeding fixture is used to clamp the straight pipe, and dock the straight pipe with the straight pipe clamping mechanism under the drive of the feeding robot arm (12).
6. The pipe elbow assembly workstation according to claim 5, characterized in that: The bent pipe feeding fixture (13) includes a fixture mounting seat (15) connected to the end of the feeding robot arm (12), and a three-jaw clamping assembly 2 (16) and a three-jaw clamping assembly 3 (17) respectively connected to the fixture mounting seat (15); The three-claw clamping assembly 2 (16) is used to clamp the outer wall of the first end of the elbow from the radial direction; The three-claw clamping assembly (17) includes a first clamping cylinder (18), a second clamping cylinder (19) and a third clamping cylinder (20) respectively connected to the clamp mounting base (15), the first clamping cylinder (18) extends into the inner hole of the second end of the bent pipe and is used to push the inner wall of the inner hole of the second end of the bent pipe, the second clamping cylinder (19) and the third clamping cylinder (20) are symmetrically arranged on both sides of the first clamping cylinder (18) and are respectively used to push the outer wall of the second end of the bent pipe.