High-pressure movable elbow pipe blank machining positioning tooling and method

Abstract

This invention relates to the field of high-pressure movable elbow processing technology, specifically a positioning fixture and method for processing high-pressure movable elbow tube blanks. The fixture includes a linear motion mechanism for controlling the axial displacement of the tube blank relative to the saw blade on a sawing machine; a rotating mechanism mounted on the linear motion mechanism for controlling the angle between the tube blank and the saw blade; and a positioning mechanism mounted on the rotating mechanism for positioning the thinnest and thickest positions of the tube blank. This fixture enables rapid clamping of tube blanks with eccentric holes, is simple and convenient to operate, and provides a strong and secure clamping. Combined with machine tool processing, it can quickly achieve corner cutting of movable elbow blanks, solving the problems of outer diameter collapse and inner diameter bulging in the elbow, thus improving the processing efficiency and quality of movable elbows.

Description

Technical Field

[0001] This invention relates to the field of high-pressure movable elbow processing technology, specifically a positioning tool and method for processing high-pressure movable elbow tube blanks. Background Technology

[0002] High-pressure flexible elbows are pipe fittings designed to accommodate the bending of pipelines when transporting high-pressure fluids. They are widely used in practical engineering, such as oilfield drilling, cementing, and fracturing operations. Due to their special working environment and requirements, strict dimensional accuracy is required. Most existing high-pressure elbow manufacturing processes use pipe blank bending. During the bending process, the outer wall is subjected to tension and the inner wall to compression, forcing the outer wall thickness of the bend to decrease while the inner wall thickness increases. This necessitates further finishing of the inner hole (straight section), outer wall (straight section), and both ends of the bend, resulting in a large workload. Furthermore, the 90° bend in the pipe blank makes processing extremely difficult, affecting the dimensional accuracy after forming.

[0003] Therefore, existing patents propose an eccentric design scheme for the tube blank, forming a tube blank with a structure that gradually thickens from the inner wall to the outer wall. For example, in the non-uniform wall thickness tube bending forming method published in CN108506588A, to ensure uniform wall thickness, the center hole is eccentrically machined before manufacturing. However, in actual manufacturing, although the center hole is eccentrically machined, the metal does not have uniform flowability during bending, resulting in different flowability in different parts. Simulation experiments show that... Figure 1 Without an additional pushing mechanism, under the action of the bending die mechanism alone, after the tube blank is bent, due to compression at the inner diameter and tension at the outer diameter, the tube wall near the inner diameter is longer than the tube wall near the outer diameter due to metal flow under compression. That is, after bending, the tube length gradually increases from the thick-walled side to the thin-walled side. At the same time, due to tension, the outer wall bends are prone to material shortages and incomplete outer wall filling. Figure 2 Under the combined action of the push mechanism and the bending die mechanism of the pipe bending machine, during the bending process, the inner wall is pushed when bending, and material is easily piled up at the inner wall bend, resulting in excessive wall thickness. The large end of the pipe blank is generally processed into the female end of the bend, and the small end is generally processed into the male end of the bend.

[0004] Therefore, in response to this problem, through continuous simulation experiments and in-plant processing experiments, it was found that before the bending and forming process, the small end of the tube blank can be chamfered first, so that the length of the tube blank from the outer wall to the inner wall gradually decreases. With the addition of the pushing action, the problem of material accumulation and bulging at the inner wall bend and material shortage and collapse at the outer wall bend can be solved after the tube blank is bent. However, since the outer surface of the tube blank is circular, it is very difficult to measure and position the thinnest and thickest parts of the eccentric tube blank, and the chamfering of the end of the eccentric tube is very difficult. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a high-pressure movable elbow tube blank machining positioning tooling and method that can achieve eccentric tube blank positioning and fixing, facilitating corner cutting machining.

[0006] The technical solution adopted by this invention to solve its technical problem is:

[0007] A high-pressure movable elbow tube blank processing positioning fixture includes a linear motion mechanism for controlling the axial displacement of the tube blank relative to the saw blade on the sawing machine; a rotation mechanism, mounted on the linear motion mechanism, for controlling the included angle between the tube blank and the saw blade; and a positioning mechanism, mounted on the rotation mechanism, for positioning the tube blank at its thinnest and thickest positions.

[0008] As a preferred embodiment, a further technical solution of the present invention is:

[0009] Preferably, the positioning mechanism includes a positioning seat and a support seat spaced apart along the linear motion direction. The support seat is machined with a V-shaped groove for supporting the tube blank. The positioning seat is machined with a limiting groove on the side near the support seat that is adapted to the large end of the tube blank. An eccentric shaft adapted to the eccentric hole of the tube blank is provided in the limiting groove.

[0010] Preferably, the eccentric shaft and the limiting groove are eccentrically arranged in the horizontal direction.

[0011] Preferably, the linear motion mechanism includes a horizontally arranged sliding base with a slide rail along its longitudinal direction; a first mounting seat is also provided on the sliding base, and a lead screw is rotatably connected to the first mounting seat; the mechanism also includes a first handle, which is connected to the end of the lead screw via a connecting shaft; it also includes a horizontally arranged slide table, with a rotating mechanism mounted on the slide table; a slider is provided on the lower side of the slide table corresponding to the slide rail, and the slider is slidably connected to the slide rail; a limit block is also provided on the lower side of the slide table, and a guide threaded hole is provided on the limit block, which is threadedly engaged with the lead screw through the guide threaded hole.

[0012] Preferably, the rotating mechanism includes a second mounting base disposed on the slide and a rotating column rotatably disposed on the right side of the slide. A turntable is disposed on the rotating column, and a positioning mechanism is mounted on the turntable. A double-ended screw is rotatably connected to the second mounting base. A second handle is disposed at the left end of the double-ended screw. The central axis of the double-ended screw intersects and is perpendicular to the central axis of the turntable. The left and right threads of the double-ended screw are arranged in opposite directions. A first nut is threaded onto the left thread, and a second nut is threaded onto the right thread. The first nut is fixedly connected to... The device includes a first guide shaft and a second threaded nut with a first limiting hole. The first guide shaft is slidably inserted into the second threaded nut through the first limiting hole. A second guide shaft is fixed to the second threaded nut, and a second limiting hole is opened on the first threaded nut. The second guide shaft is slidably inserted into the first threaded nut through the second limiting hole. The first guide shaft and the second guide shaft are parallel to the double-ended screw and are located on both sides of the double-ended screw. Guide blocks are provided on both the first guide shaft and the second guide shaft. The device also includes a connecting rod, one end of which is hinged to the guide block and the other end of which is hinged to the turntable.

[0013] Preferably, the turntable has scale lines on its side and a pointer pointing to the scale lines is provided on the slide.

[0014] This invention also discloses a method for machining and positioning a high-pressure movable elbow tube blank, comprising: first, installing a high-pressure movable elbow tube blank machining and positioning fixture on a machine tool; then, installing the tube blank on a positioning mechanism, with the positioning mechanism limiting the tube blank; then, adjusting a rotation mechanism to adjust the included angle between the tube blank and the saw blade to a preset angle; and finally, adjusting a linear motion mechanism to slide the tube blank to the underside of the saw blade for corner cutting.

[0015] The present invention, which adopts the above technical solution, has the following prominent features compared with the prior art:

[0016] This fixture enables rapid clamping of tube blanks with eccentric holes. The positioning seat and support seat limit the thinnest and thickest positions of the eccentric tube blank. The linear motion mechanism facilitates adjustment of the distance between the eccentric tube blank and the saw blade, and the rotation mechanism facilitates adjustment of the included angle between the eccentric tube blank and the saw blade. The operation is simple and convenient, and the clamping is firm and secure. When used with a machine tool, it can quickly achieve the corner cutting of the movable bend blank. In addition, the pushing action makes the bent end of the movable bend flatter, and the wall thickness at the bend and the small end more uniform, improving the processing efficiency and quality of the movable bend. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the tube blank after bending under the action of the bending die mechanism in the existing technology;

[0018] Figure 2 This is a schematic diagram of the tube blank after bending under the combined action of the jacking mechanism and the bending die mechanism in the existing technology;

[0019] Figure 3 This is a schematic diagram of the tube blank shape after the tube blank is chamfered before the bending process in an embodiment of the present invention;

[0020] Figure 4 This is a schematic diagram of the structure of the high-pressure movable elbow tube blank processing and positioning tooling in this embodiment of the invention.

[0021] Figure 5 This is a schematic diagram of the high-pressure movable elbow tube blank processing and positioning fixture in an embodiment of the present invention;

[0022] Figure 6 This is a side view of the tube blank mounted on the positioning fixture in an embodiment of the present invention;

[0023] Figure 7 yes Figure 6 A schematic diagram of the cross-sectional structure of AA;

[0024] Figure 8 This is a top view schematic diagram of the tube blank processing positioning fixture in an embodiment of the present invention;

[0025] Figure 9 This is a schematic diagram of the rotating mechanism in an embodiment of the present invention;

[0026] Figure 10 This is a schematic diagram of the tube blank after it has been bent under the combined action of the pushing mechanism and the bending die mechanism in an embodiment of the present invention.

[0027] Explanation of reference numerals in the attached drawings: 1. Positioning seat; 101. Limiting groove; 102. Eccentric shaft; 2. Support seat; 201. V-groove; 3. Sliding base; 4. Slide rail; 5. First mounting seat; 6. Rotating shaft; 7. First handle; 8. Slider; 9. Limiting block; 10. Slide table; 11. Second mounting seat; 12. Rotating column; 13. Turntable; 14. Second handle; 15. Double-ended screw; 1501. Left thread; 1301. Scale line; 1502. Right thread; 16. First guide shaft; 17. Second guide shaft; 18. First nut; 19. Second nut; 20. Guide block; 21. Tube blank; 2101. Thin-walled side; 2102. Thick-walled side; 2103. Small end; 2104. Large end; 22. Connecting rod; 23. Pointer. Detailed Implementation

[0028] The present invention will be further illustrated below with reference to specific embodiments. The purpose of this illustration is solely to provide a better understanding of the invention. Therefore, the examples given do not limit the scope of protection of the present invention.

[0029] like Figure 1This is the shape of the tube blank 21 after bending under the action of the bending die mechanism in the simulation experiment. As can be seen from the figure, the eccentric tube blank 21 without any treatment (the tube blank 21 with eccentric tube processing) will have the problem of the small end 2103 tilting downward and outward from the thick wall side 2102 to the thin wall side 2101 after bending. At the same time, material shortage is prone to occur at the bend corner of the outer wall (thick wall side 2102); for example Figure 2 This is the shape of the tube blank 21 after bending under the combined action of the jacking mechanism and the bending die mechanism in the simulation experiment. The yellow part represents the simulation result, and the gray part represents the standard elbow part model. Figure 2 It is known that material accumulation and excessive wall thickness are prone to occur at the bends of the inner wall (thin-walled side 2101). Therefore, to address this issue, through continuous simulation experiments and in-plant processing experiments, it was found that before the bending and forming process, a chamfering treatment can be performed at the small end 2103 of the tube blank 21, such as... Figure 3 This causes the length of the tube blank 21 from the outer wall to the inner wall to gradually decrease, thus solving the problems of material accumulation at the bend of the thin-walled side 2101 and material shortage at the bend of the thick-walled side 2102 after the tube blank 21 is bent.

[0030] However, since the outer surface of the tube blank 21 is circular and the central hole is eccentric, how to locate the thinnest and thickest parts of the eccentric tube blank 21 and perform corner cutting on the eccentric tube blank 21 has become an urgent problem to be solved by those skilled in the art.

[0031] like Figures 4 to 9 As shown in the figure, this embodiment provides a positioning fixture for processing high-pressure movable elbow tube blanks, including a linear motion mechanism for controlling the axial displacement of the tube blank 21 relative to the saw blade on the sawing machine; a rotation mechanism, mounted on the linear motion mechanism, for controlling the included angle between the tube blank 21 and the saw blade; and a positioning mechanism, mounted on the rotation mechanism, for positioning the tube blank 21 at its thinnest and thickest positions.

[0032] The method for positioning high-pressure movable elbow tube blanks using a high-pressure movable elbow tube blank machining positioning fixture includes: first, installing the high-pressure movable elbow tube blank 21 machining positioning fixture on a machine tool; then, installing the tube blank 21 on a positioning mechanism, whereby the positioning mechanism limits the tube blank 21; then, adjusting the rotation mechanism to adjust the included angle between the tube blank 21 and the saw blade to a preset angle; and finally, adjusting the linear motion mechanism to slide the tube blank 21 to the underside of the saw blade for corner cutting.

[0033] like Figure 4 , Figure 5As shown, the positioning mechanism specifically includes a positioning seat 1 and a support seat 2 spaced apart along the linear motion direction. The support seat 2 is machined with a V-shaped groove 201 for supporting the tube blank 21. The positioning seat 1 is machined with a limiting groove 101 on the side near the support seat 2, which is adapted to the large end 2104 of the tube blank 21. An eccentric shaft 102 adapted to the eccentric hole of the tube blank 21 is provided in the limiting groove 101. The eccentric shaft 102 and the limiting groove 101 are eccentrically arranged in the horizontal direction.

[0034] like Figure 4 , Figure 6 As shown, insert the large end 2104 of the tube blank 21 into the limiting groove 101. At this time, constrained by the eccentric shaft 102, the side with the thickest skin of the tube blank 21 is located on the far left, and the side with the thinnest skin of the tube blank 21 is located on the far right. The side with the thickest skin and the side with the thinnest skin are on the same horizontal line. When sawing at an angle, install this fixture on the machine tool and the saw blade can work vertically downwards. There is no need to adjust the saw blade angle. It is ready to use immediately and is simple and convenient.

[0035] like Figure 4 , Figure 5 As shown, the linear motion mechanism includes a horizontally arranged sliding base 3, which is rectangular in top view. A slide rail 4 is arranged along the length of the sliding base 3, and two slide rails 4 are spaced apart along the width of the sliding base 3. A set of two first mounting seats 5 are also provided on the sliding base 3, located at the left and right ends of the sliding base 3 respectively. A continuous lead screw is rotatably connected to the two first mounting seats 5 through bearings and connecting rods. A first handle 7 is provided on the outer side of the left first mounting seat 5, and the first handle 7 is connected to the lead screw through a connecting shaft. A limit nut is provided on the outer side of the right first mounting seat 5, and the limit nut is connected to the end of the lead screw through a connecting shaft. It also includes a horizontally arranged slide table 10, a rotating mechanism mounted on the slide table 10, and a slider 8 corresponding to the slide rail 4 on the lower side of the slide table 10. The slider 8 is slidably connected to the slide rail 4. A limit block 9 is also provided on the lower side of the slide table 10. The limit block 9 is provided with a guide thread hole and is threaded with the lead screw through the guide thread hole. By manually cranking the first handle 7, the rotating shaft 6 can be driven to rotate forward or reverse, thereby causing the limit block 9 to move along the lead screw and causing the slide table 10 to slide left and right along the slide rail 4. The extension angle of the thread on the lead screw is 30 degrees, that is, a trapezoidal lead screw is used in the prior art, so that the limit block 9 can achieve self-locking when it moves on the lead screw.

[0036] like Figures 7 to 9As shown, the rotating mechanism includes a second mounting base 11 mounted on the slide table 10 and a rotating column 12 rotatably mounted on the right side of the slide table 10. A turntable 13 is mounted on the rotating column 12, and a positioning mechanism is mounted on the turntable 13. There are two second mounting bases 11, and a double-ended screw 15 is rotatably connected to the two second mounting bases 11 through a bearing seat and a rotating shaft 6. A second handle 14 is provided on the outer side of the left second mounting base 11. The second handle 14 is connected to the left end of the double-ended screw 15 through the rotating shaft 6. The central axis of the double-ended screw 15 intersects and is perpendicular to the central axis of the turntable 13. The left thread 1501 and the right thread 1502 of the double-ended screw 15 are arranged in opposite directions. A first nut 18 is threaded onto the left thread 1501, and the right thread 1502 is threaded onto the right thread 1502. A second nut 19 is threaded onto thread 1502. A first guide shaft 16 is fixedly connected to a first nut 18. A first limiting hole is provided on the second nut 19, and the first guide shaft 16 is slidably inserted into the second nut 19 through the first limiting hole. A second guide shaft 17 is fixedly connected to the second nut 19. A second limiting hole is provided on the first nut 18, and the second guide shaft 17 is slidably inserted into the first nut 18 through the second limiting hole. The first guide shaft 16 and the second guide shaft 17 are arranged parallel to the double-ended screw 15 and are located on both sides of the double-ended screw 15. Guide blocks 20 are provided on both the first guide shaft 16 and the second guide shaft 17. A connecting rod 22 is also included, with one end of the connecting rod 22 hinged to the guide block 20 and the other end hinged to the turntable 13.

[0037] When the second handle 14 is cranked, the first nut 18 and the second nut 19 move towards or away from each other. When the second handle 14 is cranked and the first nut 18 and the second nut 19 move towards each other, the first nut 18 drives the first guide shaft 16 to move to the right, and the second nut 19 drives the second guide shaft 17 to move to the left. This, in turn, drives the guide blocks 20 on the first guide shaft 16 and the second guide shaft 17 to move to the right and left respectively, thereby driving the turntable 13 to rotate counterclockwise. When the second handle 14 is cranked and the first nut 18 and the second nut 19 move away from each other, the first nut 18 drives the first guide shaft 16 to move to the left, and the second nut 19 drives the second guide shaft 17 to move to the right. This, in turn, drives the guide blocks 20 on the first guide shaft 16 and the second guide shaft 17 to move to the left and right respectively, thereby driving the turntable 13 to rotate clockwise. This serves to adjust the angle of the tube blank 21 installed on the turntable 13.

[0038] like Figure 6 , Figure 8 The turntable 13 has a scale line 1301 on its side to indicate the rotation angle. The slide table 10 has a pointer 23 pointing to the scale line 1301. The pointer 23 has a Z-shaped structure, including a first vertical part, a second vertical part and a horizontal part. The lower end of the first vertical part is connected to the turntable 13, and the upper end of the second vertical part points to the scale line 1301. A reinforcing rib is provided between the first vertical part and the horizontal part.

[0039] like Figure 1 , Figure 6 As shown, this fixture enables rapid clamping of tube blanks with eccentric holes. The positioning seat 1 and support seat 2 limit the thinnest and thickest positions of the eccentric tube blank 21. The linear motion mechanism facilitates adjustment of the distance between the eccentric tube blank 21 and the saw blade, while the rotation mechanism facilitates adjustment of the angle between them. Operation is simple and convenient, and the clamping is robust and secure. Combined with machine tool processing, it can quickly achieve corner cutting of movable bending tube blanks; for example... Figure 3 This is a schematic diagram of the structure of a flexible bend blank after the chamfering process, as shown below. Figure 10 After the corners are cut, the tube blank 21 is bent by the combined action of the push mechanism and the bending die mechanism, resulting in a flatter end and more uniform wall thickness at the bend, which improves the processing quality and shortens the subsequent finishing processing time.

[0040] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. All equivalent changes made based on the description and drawings of the present invention are included within the scope of the present invention.

Claims

1. A high-pressure active bend tube blank machining positioning tooling, characterized in that: The utility model relates to a pipe blanking sawing machine, including linear motion mechanism for controlling the axial displacement of pipe blank (21) relative to saw blade on sawing bed, rotating mechanism is installed on linear motion mechanism for controlling the included angle between pipe blank (21) and saw blade, positioning mechanism is installed on rotating mechanism for positioning the thinnest position and the thickest position of pipe blank (21) skin thickness, positioning mechanism includes the positioning seat (1) and support seat (2) of interval arrangement along the linear motion direction, support seat (2) is processed with V type groove (201) for supporting pipe blank (21) on, positioning seat (1) is processed with the limit groove (101) of adapting with the big head end (2104) of pipe blank (21) on the side close to support seat (2), limit groove (101) is provided with eccentric shaft (102) adapting with the eccentric hole of pipe blank (21), eccentric shaft (102) and limit groove (101) are eccentric in horizontal direction, Linear motion mechanism includes horizontally arranged sliding bottom support (3), and sliding bottom support (3) is provided with sliding rail (4) along the length direction on, sliding bottom support (3) is also provided with first mounting seat (5), and first mounting seat (5) is rotatably connected with lead screw, and first handle (7) is connected with the end of lead screw through connecting shaft, sliding table (10) is horizontally arranged, and rotating mechanism is installed on sliding table (10), and the lower side of sliding table (10) is provided with sliding block (8) corresponding to sliding rail (4), and sliding block (8) is slidably connected on sliding rail (4), and the lower side of sliding table (10) is also provided with limiting block (9), and the limiting block (9) is provided with guide screw hole, and limiting block (9) is threadedly connected with lead screw through guide screw hole, rotating mechanism includes second mounting seat (11) arranged on sliding table (10) and rotating column (12) rotatably arranged on the right side of sliding table (10), and rotating column (12) is provided with rotating disc (13), and positioning mechanism is installed on rotating disc (13), Second mounting seat (11) is rotatably connected with double-headed screw (15), and the left end of double-headed screw (15) is provided with second handle (14), and the central axis of double-headed screw (15) intersects with the central axis of rotating disc (13) and is perpendicular to each other, and the left thread (1501) and right thread (1502) of double-headed screw (15) are oppositely arranged, The first nut (18) is threadedly connected on the left thread (1501), the second nut (19) is threadedly connected on the right thread (1502), the first guide shaft (16) is fixedly connected on the first nut (18), the first limiting hole is formed in the second nut (19), and the first guide shaft (16) is slidably inserted into the second nut (19) through the first limiting hole, the second guide shaft (17) is fixedly connected on the second nut (19), the second limiting hole is formed in the first nut (18), and the second guide shaft (17) is slidably inserted into the first nut (18) through the second limiting hole, the first guide shaft (16) and the second guide shaft (17) are parallel to the double-headed screw (15) and are located on the two sides of the double-headed screw (15) respectively, and the guide block (20) is arranged on the first guide shaft (16) and the second guide shaft (17). A connecting rod (22) is further included, one end of the connecting rod (22) is hinged with the guide block (20), and the other end is hinged with the rotating disc (13).

2. The high pressure malleable bend tube blank machining positioning tooling of claim 1, wherein: The rotating disc (13) is provided with a scale line (1301) on the side, and the slide table (10) is provided with a pointer (23) pointing to the scale line (1301).

3. A method of positioning a high-pressure malleable elbow tube blank, characterized in that The utility model discloses a high-pressure movable elbow pipe blank positioning device and method, and belongs to the field of pipe machining. First, the high-pressure movable elbow pipe blank (21) is installed on the machine tool, then the pipe blank (21) is installed on the positioning mechanism, the positioning mechanism limits the pipe blank (21), then the rotating mechanism is adjusted, the included angle between the pipe blank (21) and the saw blade is adjusted to the preset angle, finally, the linear motion mechanism is adjusted, the pipe blank (21) is slid to the lower side of the saw blade, and the angle cutting operation can be carried out.

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