Nickel-based special-shaped pipe cold-drawing forming process

Abstract

The invention relates to a cold-drawing forming process for a nickel-based special-shaped pipe, and belongs to the technical field of pipe machining. Comprising the following steps: S1, raw material and smelting process; s2, preparing a pierced billet; s3, cold deformation control; s4, finished product treatment and performance; and S5, quality detection standard. The cold-drawing machine comprises a machine body, a mounting base is fixedly arranged at the top of one end of the machine body, and two cutting frames are arranged on one side of the mounting base. Cutting, extruding and grinding and a driving mechanism are integrated, efficient and accurate machining of a pipe is achieved, the cutting frames are provided with double motors to drive cutting blades, and it is ensured that a rectangular opening is accurately formed in the end of the pipe; the extrusion mechanism flexibly forms an arc-shaped part and a bent part of the pipe by utilizing a slidable support frame and a rotary polishing design; and the driving mechanism realizes stable movement and resetting of the cutting frame through an electric push rod and a guide structure, and drives the extrusion mechanism to work at the same time.

Description

Technical Field

[0001] The invention belongs to the technical field of tube processing and relates to a cold drawing forming process for a nickel-based special-shaped tube. Background Art

[0002] Nickel-based pipes are alloy pipes made of nickel as the base material, which are formed by adding various alloy elements such as chromium, molybdenum, tungsten, cobalt, and iron. The synergistic effect of these alloy elements gives nickel-based pipes excellent high-temperature strength, good oxidation resistance, excellent corrosion resistance and fatigue resistance. With its excellent comprehensive performance, nickel-based pipes have shown broad application prospects in the fields of aerospace, nuclear energy and chemical industry, and are especially suitable for the manufacture of aircraft engines, high-temperature components of spacecraft and reactor heaters of nuclear submarines.

[0003] The traditional cold drawing process of nickel-based special-shaped tubes has the following problems: 1. Insufficient smelting process. Traditional AOD+ESR smelting is adopted, the level of inclusion control is low (A / B / C / D inclusions are not clearly restricted), and the purity is insufficient, which affects the uniformity and corrosion resistance of the material.

[0004] 2. The defects of the rough tube forming method. The traditional hot extrusion process easily leads to low dimensional accuracy and uneven wall thickness of the rough tube, making subsequent cold processing difficult and difficult to ensure the geometric accuracy of the finished product.

[0005] 3. In the cold drawing process of nickel-based pipes, cold drawing equipment is usually used to plastically form the pipes. During cold drawing, the pulling mechanism needs to fix and clamp one end of the pipe, and use the pulling force to shape the other end of the pipe through the die. Because the end of the pipe is plastically deformed by the tensile force during the cold drawing process, the contact area between it and the clamping plate of the pulling mechanism is reduced, which can easily lead to clamping failure, causing scratches on the surface of the pipe or dimensional deviations, seriously affecting the quality of cold drawing.

[0006] Therefore, we proposed a nickel-based special-shaped tube cold drawing process to solve the above-mentioned problems. Summary of the invention

[0007] In view of this, the present invention provides a nickel-based special-shaped tube cold drawing forming process to solve the problem that the tube end is deformed after extrusion, cannot fully contact with the clamping plate in the pulling mechanism, is easily separated during the pulling process, and affects the cold drawing effect.

[0008] To achieve the above object, the present invention provides the following technical solution: a nickel-based special-shaped tube cold drawing forming process, comprising the following steps:

[0009] S1. Raw materials and smelting process: The raw material specifications adopt a multi-stage diameter expansion process, such as 167×19 gradually expanded to 219×6.5, and finally cold drawn to 204×177.3×6;

[0010] The smelting process is upgraded to triple type (VIM+LF+ESR), replacing the original AOD+ESR, controlling the inclusion level (A / B / C / D<1.5, DS<1.0) and improving purity;

[0011] S2. Preparation of rough pipe: the rough pipe is changed from hot extrusion to hot perforation process (stripping + drilling + double hot expansion) to ensure dimensional accuracy and uniformity of wall thickness;

[0012] Pretreatment process: pipe cutting → pickling → internal and external polishing → multiple cold expansion and rolling → cold drawing using a cold drawing machine;

[0013] S3. Cold deformation control: The cold rolling deformation pass is controlled at 35-42%, and the elongation is 30-35%; the cold drawing elongation is controlled at 15-22%;

[0014] The production process uses multiple passes of precision cold deformation to ensure geometric dimensional stability;

[0015] S4. Finished product processing and performance: Solution treatment temperature is 1080±5℃, which meets Grade 1 standard (1080-1120℃±5℃);

[0016] Mechanical properties: yield strength ≥414MPa, tensile strength ≥827MPa, elongation ≥30%, HRB ≤90;

[0017] S5, quality inspection standards: surface roughness Ra ≤ 0.4μm, straightness < 1.0mm / m, full length curvature < 0.10%;

[0018] Torsion degree ≤1.0mm / m, edge convexity ≤0.08mm, fillet radius R<10.

[0019] Furthermore, a cold drawing machine is used to process the pipe, and the cold drawing machine comprises:

[0020] The machine body has a mounting seat fixedly arranged on the top of one end;

[0021] The cutting mechanism is arranged on one side of the mounting seat, and includes two cutting frames, each of which is fixedly provided with a first motor, the output end of the first motor passes through the cutting frame and is fixedly connected with a first cutting blade, and a second motor is fixedly provided on one side of the cutting frame, the output end of the second motor is fixedly connected with a second cutting blade, and is used for cutting two rectangular openings at the end of the pipe;

[0022] The extrusion mechanism is arranged on the other side of the mounting seat, and includes two slidably arranged support frames, the bottom of which is fixedly connected with a first semicircular block, and the two first semicircular blocks are combined to form a complete circle; a semicircular guide rail is embedded in one side of the first semicircular block, and a second semicircular block is fixedly connected to the outer end of the semicircular guide rail, and a conical cavity is opened in the second semicircular block, and an arc cavity and a rectangular groove are opened on one side of the first semicircular block, which are used to extrude the pipe to form an arc portion and a bending portion;

[0023] The driving mechanism comprises a mounting plate fixedly arranged on one side of the mounting seat, and two electric push rods are arranged through the mounting plate. The output ends of the electric push rods are connected to the cutting frame to drive the cutting frame to move and reset, and to link the extrusion mechanism to extrude the pipe.

[0024] Furthermore, an extension block is fixedly provided on one side of the first semicircular block, a third motor is fixedly provided on one side of the extension block, an output end of the third motor passes through the extension block and is fixedly sleeved with a first gear, a semi-toothed ring meshing with the first gear is fixedly provided on the outer wall of the second semicircular block, and the two semi-toothed rings form a complete toothed ring for driving the second semicircular block to rotate to grind the rectangular opening.

[0025] Furthermore, the driving mechanism further comprises:

[0026] The first connecting block and the second connecting block are respectively fixedly arranged at the output ends of the two electric push rods and slidably arranged at one side of the mounting seat;

[0027] The lifting frame is fixedly arranged on one side of the cutting frame, and a rectangular hole is opened on one side of the lifting frame. A first guide groove matching with the rectangular hole is opened on the top of the first connecting block, and a second guide groove matching with the rectangular hole is opened on the top of the second connecting block, which is used to drive the two cutting frames away from each other when the electric push rod is reset to avoid being stuck with the pipe.

[0028] Furthermore, a first guide rod is fixedly provided on the other side of the cutting frame, a waist-shaped hole is opened on one side of the mounting plate, one end of the first guide rod is slidably set in the waist-shaped hole, and a limiting ring is sleeved on the outer wall of the first guide rod. The limiting ring is slidably set on one side of the mounting plate through a sliding groove, and a first tension spring is also sleeved on the outer wall of the first guide rod, and the two ends of the first tension spring are respectively fixedly connected to the limiting ring and the cutting frame.

[0029] Furthermore, a connecting frame is fixedly provided on the top of the lifting frame above, and the connecting frame is L-shaped, and the other end cooperates with one of the supporting frames. A second fixed block is fixedly provided on one side of the mounting seat, and a second gear is rotatably provided on the top of the second fixed block; a rack meshing with the second gear is fixedly provided on the side of the two supporting frames close to each other, which is used to drive the two supporting frames to approach each other.

[0030] Furthermore, two first fixed blocks are fixedly provided on one side of the mounting seat, two second guide rods are fixedly provided between the first fixed block and the second fixed block, the support frame is slidably sleeved on the second guide rods, and the outer wall of one of the second guide rods is sleeved with a second tension spring, and the two ends of the second tension spring are respectively fixedly connected to the first fixed block and the side of the support frame close to each other.

[0031] Furthermore, a second clearance opening is provided on the top of one of the first fixing blocks to avoid the moving path of the connecting frame.

[0032] Furthermore, the output end of the first motor is sleeved with a positioning ring, which is fixedly arranged at the bottom of the cutting frame and is used for axial positioning of the pipe.

[0033] Furthermore, the first cutting blade and the second cutting blade are made of YG8 cemented carbide, and the specification of the first cutting blade is Φ150×3mm.

[0034] The beneficial effects of the present invention are:

[0035] 1. The cold drawing forming process of the nickel-based special-shaped tube disclosed in the present invention comprises a machine body, a mounting seat, a cutting frame, a first motor, a second motor, an extrusion mechanism and a driving mechanism. The overall structure is compact and fully functional. The first motor and the second motor on the cutting frame can cut one end of the tube respectively to form two rectangular openings, which provide conditions for subsequent extrusion and grinding. A positioning ring is provided at the output end of the first motor for positioning the tube, ensuring the stability of the cutting process, avoiding the movement or deviation of the tube during the cutting process, and further improving the cutting accuracy.

[0036] 2. The cold drawing forming process of nickel-based special-shaped tube disclosed in the present invention can extrude and grind the cut tube to form an arc portion and a bending portion by cooperating with two support frames slidingly arranged on one side of the mounting seat, a first semicircular block, a semicircular guide rail, a second semicircular block and other components, which not only improves the forming accuracy of the tube, but also facilitates the pulling mechanism to clamp one end of the tube, and the second semicircular block is driven to rotate by the third motor to grind the cut rectangular opening, ensuring the smoothness of the tube surface and the consistency of the shape;

[0037] 3. The cold drawing forming process for nickel-based special-shaped tubes disclosed in the present invention uses an electric push rod to drive the cutting frame to move, and in the process of resetting, it cooperates with the pipe to move and reset, and drives the extrusion mechanism to extrude the pipe. This design realizes the automation of the cutting, extrusion and resetting process, improves production efficiency, and the output end of the electric push rod is provided with a first connecting block and a second connecting block, which cooperate with the lifting frame on the cutting frame, and drive the two cutting frames away from each other through the first guide groove and the second guide groove, thereby avoiding the pipe from getting stuck during the resetting process and ensuring the stable operation of the equipment;

[0038] 4. Smelting process optimization: Triple smelting (VIM+LF+ESR): significantly improve material purity (inclusions A / B / C / D type <1.5, DS <1.0), reduce grain boundary impurities, enhance corrosion resistance and high temperature strength, and adapt to the extreme service environment of nuclear ships.

[0039] Upgrade of rough pipe forming process: hot perforation replaces hot extrusion (peeling + punching + double hot expansion): improves wall thickness uniformity (error <0.2mm), reduces subsequent cold processing allowance, reduces material loss, and improves finished product size consistency.

[0040] Casting → Cold Drawing Transformation: Avoid casting defects (pores, shrinkage) and improve density; through multiple precision cold deformation (such as final drawing specifications 204×177.3×6), high-precision forming of hexagonal special-shaped tubes is achieved to adapt to complex service loads.

[0041] The present invention realizes efficient and precise processing of pipes by integrating cutting, extrusion grinding and driving mechanism. The cutting frame is equipped with a dual-motor driven cutting blade to ensure that a rectangular opening is accurately formed at the end of the pipe; the extrusion mechanism utilizes a slidable support frame and a rotary grinding design to flexibly form an arc portion and a bent portion of the pipe; the driving mechanism realizes stable movement and resetting of the cutting frame through an electric push rod and a guide structure, and drives the extrusion mechanism to work at the same time.

[0042] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0044] Figure 1 It is a three-dimensional structural schematic diagram of a cold drawing machine in the cold drawing forming process of a nickel-based special-shaped tube of the present invention;

[0045] Figure 2 It is a schematic diagram of the structure of the cold drawing machine after the tube is cut in the cold drawing forming process of the nickel-based special-shaped tube of the present invention;

[0046] Figure 3 It is a schematic diagram of the structure of the cold drawing machine after the tube is extruded in the cold drawing forming process of the nickel-based special-shaped tube of the present invention;

[0047] Figure 4 It is a schematic diagram of the installation structure of the cutting frame and the electric push rod of the cold drawing machine in the cold drawing forming process of the nickel-based special-shaped tube of the present invention;

[0048] Figure 5 It is a schematic diagram of the installation structure of the cutting blade and the cutting frame of the cold drawing machine in the cold drawing forming process of the nickel-based special-shaped tube of the present invention;

[0049] Figure 6 It is a schematic diagram of the cutting frame and the connecting block structure of the cold drawing machine in the cold drawing forming process of the nickel-based special-shaped tube of the present invention;

[0050] Figure 7 It is a schematic diagram of the extrusion mechanism structure of the cold drawing machine in the cold drawing forming process of the nickel-based special-shaped tube of the present invention;

[0051] Figure 8 It is a schematic cross-sectional structure diagram of a rotating ring and a fixed ring of a cold drawing machine in the cold drawing forming process of a nickel-based special-shaped tube of the present invention;

[0052] Fig. 9 It is a schematic diagram of the support frame structure of the cold drawing machine in the cold drawing forming process of the nickel-based special-shaped tube of the present invention.

[0053] Figure numerals: 1, machine body; 2, pipe; 3, mounting seat; 4, electric push rod; 5, cutting frame; 6, first motor; 7, first cutting blade; 8, second motor; 9, second cutting blade; 10, rectangular opening; 11, arc portion; 12, bending portion; 13, mounting plate; 14, first connecting block; 15, second connecting block; 16, lifting frame; 17, first guide rod; 18, limiting ring; 19, first tension spring; 20, waist-shaped hole; 21, connecting frame; 22, positioning ring; 23, rectangular hole; 24. First guide groove; 25. Second guide groove; 26. First semicircular block; 27. Extension block; 28. Third motor; 29. ​​First gear; 30. Rectangular groove; 31. Second semicircular block; 32. Conical cavity; 33. Semicircular guide rail; 34. Arc cavity; 35. Half-tooth ring; 36. First fixed block; 37. Second fixed block; 38. Second guide rod; 39. Second tension spring; 40. Second gear; 41. Rack; 42. First clearance opening; 43. Support frame; 44. Second clearance opening. DETAILED DESCRIPTION

[0054] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0055] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0056] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0057] Embodiment 1

[0058] The cold drawing process of nickel-based special-shaped tube includes the following steps:

[0059] S1. Raw materials and smelting process: The raw material specifications adopt a multi-stage diameter expansion process, such as 167×19 gradually expanded to 219×6.5, and finally cold drawn to 204×177.3×6;

[0060] The smelting process is upgraded to triple type (VIM+LF+ESR), replacing the original AOD+ESR, controlling the inclusion level (A / B / C / D<1.5, DS<1.0) and improving purity;

[0061] S2. Preparation of rough pipe: the rough pipe is changed from hot extrusion to hot perforation process (stripping + drilling + double hot expansion) to ensure dimensional accuracy and uniformity of wall thickness;

[0062] Pretreatment process: pipe cutting → pickling → internal and external polishing → multiple cold expansion and rolling → cold drawing using a cold drawing machine;

[0063] S3. Cold deformation control: The cold rolling deformation pass is controlled at 35-42%, and the elongation is 30-35%; the cold drawing elongation is controlled at 15-22%;

[0064] The production process uses multiple passes of precision cold deformation to ensure geometric dimensional stability;

[0065] S4. Finished product processing and performance: Solution treatment temperature is 1080±5℃, which meets Grade 1 standard (1080-1120℃±5℃);

[0066] Mechanical properties: yield strength ≥414MPa, tensile strength ≥827MPa, elongation ≥30%, HRB ≤90;

[0067] S5, quality inspection standards: surface roughness Ra ≤ 0.4μm, straightness < 1.0mm / m, full length curvature < 0.10%;

[0068] Torsion degree ≤1.0mm / m, edge convexity ≤0.08mm, fillet radius R<10.

[0069] Embodiment 2

[0070] Reference Figure 1-Figure 9 The present invention provides a new technical solution. The cold drawing machine is the key equipment of the present invention. Its structure and working principle are as follows:

[0071] The cold drawing machine includes a machine body 1, and a mounting seat 3 is fixed to the top of one end of the machine body 1 by bolts. Two cutting frames 5 are provided on one side of the mounting seat 3, and a first motor 6 is fixed to the top of the cutting frame 5 by bolts. The output end of the first motor 6 extends to the bottom of the cutting frame 5 and is fixedly connected to a first cutting blade 7 (made of YG8 cemented carbide, Φ150×3mm) by bolts. At the same time, a second motor 8 is also fixedly provided on one side of the cutting frame 5 by bolts, and the output end of the second motor 8 extends to the outer end of the cutting frame 5 and is fixedly connected to a second cutting blade 9 (made of YG8) by bolts. When the first motor 6 and the second motor 8 work and move at the same time, the first cutting blade 7 and the second cutting blade 9 will cut one end of the pipe 2 to form two rectangular openings 10.

[0072] An extrusion mechanism is provided on the other side of the mounting seat 3, which is used to extrude and grind the cut pipe 2 to form an arc portion 11 and a bent portion 12. The extrusion mechanism specifically includes two support frames 43 (material 42CrMo, quenched and tempered HRC28-32) slidingly arranged on one side of the mounting seat 3 by means of a guide rail slider, and the bottoms of the two support frames 43 are fixedly provided with a first semicircular block 26 (material GCr15, quenched HRC60-62) by welding, and the two first semicircular blocks 26 are combined to form a complete circle. A semicircular guide rail 33 (material Cr12MoV) is embedded on one side of the first semicircular block 26, and a second semicircular block 31 (material GCr15, quenched HRC60-62) for grinding the pipe 2 is fixedly provided at the outer end of the semicircular guide rail 33 by bolts or welding. A conical cavity 32 is provided in the second semicircular block 31 for grinding and shaping the pipe 2. At the same time, an arc-shaped cavity 34 and a rectangular groove 30 are also provided on one side of the first semicircular block 26 for extruding the tube 2 to form an arc-shaped portion 11 and a bent portion 12 .

[0073] In order to further enhance the grinding effect, an extension block 27 is fixedly provided on one side of the first semicircular block 26 by welding, and a third motor 28 is fixedly provided on one side of the extension block 27 by bolts. The output end of the third motor 28 extends to the other side of the extension block 27 and is provided with a first gear 29 through a keyway and a key fixing sleeve, and a semi-toothed ring 35 meshing with the first gear 29 is fixedly provided on the outer wall of the second semicircular block 31 by welding or bolts. When the third motor 28 is working, it will drive the second semicircular block 31 to rotate, thereby grinding the cut rectangular opening 10.

[0074] In addition, the cold drawing machine is also provided with a driving mechanism for driving the two sets of cutting frames 5 to move, and in the process of resetting, the pipe 2 is reset and moved, and at the same time, the extrusion mechanism is driven to extrude the pipe 2. The driving mechanism specifically includes a mounting plate 13 fixed on one side of the mounting seat 3 by welding, and two electric push rods 4 are fixed on one side of the mounting plate 13 by bolts. The output end of the electric push rod 4 is connected to the corresponding cutting frame 5. When the electric push rod 4 works, it will push the cutting frame 5 to move, thereby driving the first cutting blade 7 and the second cutting blade 9 to cut the pipe 2.

[0075] In order to prevent the cutting frame 5 from getting stuck with the pipe 2 during the reset movement, the output ends of the two electric push rods 4 are respectively fixed with a first connection block 14 and a second connection block 15 by bolts, and the first connection block 14 and the second connection block 15 are slidably arranged on one side of the mounting seat 3 by means of a slide block. At the same time, a lifting frame 16 is fixed on one side of the cutting frame 5 by bolts or welding, and a rectangular hole 23 is opened on one side of the lifting frame 16. A first guide groove 24 used in conjunction with the upper rectangular hole 23 is opened on the top of the first connection block 14, and a second guide groove 25 used in conjunction with the lower rectangular hole 23 is opened on the top of the second connection block 15. In this way, when the electric push rod 4 is retracted, the cutting frame 5 can be reset and moved, and when the first cutting blade 7 conflicts with the pipe 2, it continues to move, and the two lifting frames 16 can respectively cooperate with the first guide groove 24 and the second guide groove 25 to move away from each other, thereby preventing the first cutting blade 7 from conflicting with the pipe 2 and getting stuck.

[0076] In addition, a first guide rod 17 is fixedly provided on the other side of the cutting frame 5 by welding, and a waist-shaped hole 20 is provided on one side of the mounting plate 13, and one end of the first guide rod 17 is located in the waist-shaped hole 20. A limit ring 18 is slidably sleeved on the outer wall of the first guide rod 17 by means of a slideway slider, and one side of the limit ring 18 is slidably sleeved on one side of the mounting plate 13 by means of a slideway slider. At the same time, a first tension spring 19 (60Si2Mn, elastic coefficient 15N / mm) is also sleeved on the outer wall of the first guide rod 17, and the two ends of the first tension spring 19 are respectively fixedly connected to the limit ring 18 and the side of the cutting frame 5 that is close to each other. In this way, the cutting frame 5 can maintain a close distance to each other under the action of the first tension spring 19 during the movement, which can ensure the stability of the cutting, and can quickly return to the original position when resetting.

[0077] The top of the lifting frame 16 located above is also fixed with a connecting frame 21 used in conjunction with one of the support frames 43 by bolts. A second fixing block 37 is fixed by bolts or welding on one side of the mounting seat 3, and a second gear 40 is rotatably provided on the top of the second fixing block 37 through a rotating shaft and a bearing. A rack 41 meshing with the second gear 40 is fixed by welding on the sides of the two support frames 43 close to each other, which is used to drive the two support frames 43 to approach each other. At the same time, a first clearance opening 42 adapted to the rack 41 is also provided on the top of the support frame 43. When the upper lifting frame 16 moves, it can drive the connecting frame 21 to move. During the movement of the connecting frame 21, one of the support frames 43 can be pushed to move. During the movement of the support frame 43, the support frame 43 can use the force of the rack 41 and the second gear 40 to drive the other support frame 43 to move in the opposite direction, thereby driving the two support frames 43 to move relative to each other.

[0078] In addition, two first fixing blocks 36 are fixedly provided on one side of the mounting seat 3, and two second guide rods 38 are fixedly provided between the first fixing block 36 and the second fixing block 37. Two support frames 43 are slidably sleeved on the two groups of second guide rods 38, and the outer wall of one group of second guide rods 38 is also sleeved with a second tension spring 39 (elastic coefficient 30N / mm). The two ends of the second tension spring 39 are respectively fixedly connected to the first fixing block 36 and the side of the support frame 43 close to each other. This arrangement can make the support frame 43 more stable during movement and can quickly return to its original position when resetting. A second clearance opening 44 corresponding to the connecting frame 21 is also provided on the top of one of the first fixing blocks 36 to ensure that the connecting frame 21 will not be obstructed during movement.

[0079] In addition, the output end of the first motor 6 is also sleeved with a positioning ring 22, which is fixed to the bottom of the cutting frame 5. The positioning ring 22 can position the pipe 2 to ensure the accuracy of the cutting process without affecting the rotation of the output end of the first motor 6.

[0080] When in use, the device is connected to a power source, and then the pipe 2 is conveyed to one side of the machine body 1 through the conveyor, and then the electric push rod 4 is started to retract. During the retraction of the electric push rod 4, the first connecting block 14 and the second connecting block 15 can be driven to reset and move. The movement of the first connecting block 14 and the second connecting block 15 can drive the lifting frame 16 to move. The movement of the lifting frame 16 can drive the cutting frame 5 to move to the left until the cutting frame 5 moves into place, and the pipe 2 is continuously conveyed through the conveyor until one end of the pipe 2 contacts the positioning ring 22, and then the first motor 6 is started to drive the first cutting blade 7 to rotate, so as to The second motor 8 drives the second cutting blade 9 to rotate, and then the electric push rod 4 is started to extend. During the extension of the electric push rod 4, the first connecting block 14 and the second connecting block 15 can be pushed to move. The movement of the first connecting block 14 and the second connecting block 15 can drive the lifting frame 16 to move. The movement of the lifting frame 16 can drive the cutting frame 5 to move, thereby driving the first cutting blade 7 and the second cutting blade 9 to move. When the first cutting blade 7 and the second cutting blade 9 contact the pipe 2, the pipe 2 can be cut, so that two rectangular openings 10 are formed at one end of the pipe 2 until the first cutting blade 7 is away from the pipe 2.

[0081] Secondly, during the movement of the lifting frame 16, the connecting frame 21 can be driven to move, and the movement of the connecting frame 21 can push the support frame 43 on one side to move, and the movement of the support frame 43 can drive the rack 41 to move, and the movement of the rack 41 can drive the second gear 40 to rotate, and during the rotation of the second gear 40, the other rack 41 can be used to drive the support frame 43 to move, so that the two support frames 43 can approach each other, and the movement of the support frame 43 can drive the two first semicircular blocks 26 to approach each other, and the first semicircular blocks 26 can use the semicircular guide rail 33 to drive the two second semicircular blocks 31 to approach each other during the approaching process, so that a complete conical cavity 32, an arc cavity 34 and a rectangular groove 30 are formed, and the pipe 2 is continuously transported by the conveyor. During the transportation process, the cut pipe 2 can form an arc portion 11 and a bending portion 12 under the action of the conical cavity 32, the arc cavity 34 and the rectangular groove 30, so that it is convenient for the pulling mechanism on the machine body 1 to pull;

[0082] At the same time, the electric push rod 4 is started to retract. During the retraction process of the electric push rod 4, the cutting frame 5 can be driven to approach the pipe 2 until the outer side of the first cutting blade 7 contacts the pipe 2 and continues to move. The first guide groove 24 can be used to drive the upper lifting frame 16 to move upward, and the second guide groove 25 below can drive the lower lifting frame 16 to move downward. The lifting frame 16 can drive the cutting frame 5 to move during the movement. The movement of the cutting frame 5 can drive the first guide rod 17 to move in the waist-shaped hole 20 until the first cutting blade 7 is away from the surface of the pipe 2. At this time, the first cutting blade 7 can move from the right side of the pipe 2 to the left side of the pipe 2. At the same time, the lifting frame 16 can drive the connecting frame 21 to move during the reset movement, so that one side of the connecting frame 21 is away from the supporting frame 43. At the same time, the supporting frame 43 can be reset and moved under the tension of the second tension spring 39, so that the two first semicircular blocks 26 and the second semicircular blocks 31 are opened;

[0083] The pipe 2 is then pushed out of the machine body 1 by the conveyor, and the bending portion 12 is clamped by the pulling mechanism for cold drawing.

[0084] After many tests, the following data were obtained:

[0085] Specific process: Raw material specifications: 167*19→ expansion: 143*18.8→ expansion: 160*18.5→ expansion: 178*18.3→ expansion: 198*17.8→ expansion: 218*17.2→ rolling 219*15→ expansion: 210*14.5→ expansion: 235*14→ rolling: 219*6.5→ drawing: 204*177.3*6, solution temperature: 1080±5℃

[0086] 1. Use triple smelting: VIM+LF+ESR (originally AOD+ESR) to improve purity and inclusion control A, B, C, D < 1.5, DS < 1.0;

[0087] 2: The rough pipe is changed from the original hot extrusion to hot perforation (process: peeling + punching + two hot expansions) purpose: to ensure the uniformity of the size and wall thickness of the rough pipe;

[0088] 3: The rough pipe goes through: pipe cutting + pickling + internal and external polishing + multiple cold expansion, rolling + drawing;

[0089] 4: The production process undergoes multiple deformations of geometric dimensions and finally precision cold deformation;

[0090] 5: The finished product solution treatment is in accordance with Grade 11080-1120℃±5℃;

[0091] 6: Mechanical requirements: yield strength greater than or equal to 414Mpa, tensile strength ≥827, elongation ≥30, HRB ≤90;

[0092] 7: The cold rolling deformation pass is controlled at 35-42%, the elongation is controlled at 30-35%, and the cold drawing elongation is controlled at 15-22%;

[0093] 8: Product roughness Ra≤0.4UM10: Straightness control<1.0mm / m, full length curvature<0.10%, torsion≤1.0MM / m;

[0094] 9: Edge convexity <0.08mm.

[0095] The final improved technology is:

[0096] 1: After improvement, the straightness is now controlled to: 1.0mm / m, and the full length straightness is 0.15%.

[0097] 2: After improvement, R<10, previously R<18;

[0098] 3: After improvement, Ra≤0.4UM, previously it was Ra≤2.4UM.

[0099] 4: Torsion after improvement ≤1.2mm / M, torsion before improvement ≤2.5mm / M;

[0100] 5: The improvement of the convexity after improvement is ≤0.08mm, and the improvement of the convexity before improvement is ≤1.5;

[0101] 6: Torsion after improvement ≤1.0MM / m, torsion before improvement ≤2.50MM / m;

[0102] 7: Improved from original casting to cold drawing.

[0103] However, as is well known to those skilled in the art, the working principles and wiring methods of the electric push rod 4, the first motor 6, the second motor 8 and the third motor 28 are commonplace, and are conventional means or common knowledge, and will not be elaborated here. Those skilled in the art can make any optional selections according to their needs or convenience.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. Nickel-based special-shaped tube cold drawing forming process, characterized in that: The following steps are involved: S1. Raw materials and smelting process: The raw material specifications adopt a multi-stage diameter expansion process, such as 167×19 gradually expanded to 219×6.5, and finally cold drawn to 204×177.3×6; The smelting process is upgraded to triple type (VIM+LF+ESR), replacing the original AOD+ESR, controlling the inclusion level (A / B / C / D<1.5, DS<1.0) and improving purity; S2. Preparation of rough pipe: the rough pipe is changed from hot extrusion to hot perforation process (stripping + drilling + double hot expansion) to ensure dimensional accuracy and uniformity of wall thickness; Processing flow: pipe cutting → pickling → internal and external polishing → multiple cold expansion and rolling → cold drawing using a cold drawing machine; S3. Cold deformation control: The cold rolling deformation pass is controlled at 35-42%, and the elongation is 30-35%; the cold drawing elongation is controlled at 15-22%; The production process uses multiple passes of precision cold deformation to ensure geometric dimensional stability; S4. Finished product processing and performance: Solution treatment temperature is 1080±5℃, which meets Grade 1 standard (1080-1120℃±5℃); Mechanical properties: yield strength ≥414MPa, tensile strength ≥827MPa, elongation ≥30%, HRB ≤90; S5, quality inspection standards: surface roughness Ra ≤ 0.4μm, straightness < 1.0mm / m, full length curvature < 0.10%; Torsion degree ≤1.0mm / m, edge convexity ≤0.08mm, fillet radius R<10.

2. The nickel-based special-shaped tube cold drawing forming process according to claim 1, characterized in that: The pipe (2) is processed by a cold drawing machine, wherein the cold drawing machine comprises: The machine body (1) has a mounting seat (3) fixedly disposed on the top of one end thereof; A cutting mechanism is arranged on one side of the mounting seat (3), comprising two cutting frames (5), each cutting frame (5) being fixedly provided with a first motor (6), the output end of the first motor (6) passing through the cutting frame (5) and being fixedly connected with a first cutting blade (7), a second motor (8) being fixedly provided on one side of the cutting frame (5), the output end of the second motor (8) being fixedly connected with a second cutting blade (9), and being used for cutting two rectangular openings (10) at the end of the pipe (2); The extrusion mechanism is arranged on the other side of the mounting seat (3), and comprises two slidably arranged support frames (43), the bottom of the support frames (43) is fixedly connected to a first semicircular block (26), and the two first semicircular blocks (26) are combined to form a complete circle; a semicircular guide rail (33) is embedded on one side of the first semicircular block (26), and the outer end of the semicircular guide rail (33) is fixedly connected to a second semicircular block (31), a conical cavity (32) is provided in the second semicircular block (31), and an arc cavity (34) and a rectangular groove (30) are provided on one side of the first semicircular block (26), which are used to extrude the pipe (2) to form an arc portion (11) and a bent portion (12); The driving mechanism comprises a mounting plate (13) fixedly arranged on one side of the mounting seat (3), two electric push rods (4) being arranged through the mounting plate (13), the output ends of the electric push rods (4) being connected to the cutting frame (5) for driving the cutting frame (5) to move and reset, and linking the extrusion mechanism to extrude the pipe (2).

3. The nickel-based special-shaped tube cold drawing forming process according to claim 2, characterized in that: An extension block (27) is fixedly provided on one side of the first semicircular block (26), a third motor (28) is fixedly provided on one side of the extension block (27), an output end of the third motor (28) passes through the extension block (27) and is fixedly sleeved with a first gear (29), a semi-toothed ring (35) meshing with the first gear (29) is fixedly provided on the outer wall of the second semicircular block (31), the two semi-toothed rings (35) form a complete toothed ring for driving the second semicircular block (31) to rotate so as to grind the rectangular opening (10).

4. The nickel-based special-shaped tube cold drawing forming process according to claim 3, characterized in that: The driving mechanism further comprises: A first connecting block (14) and a second connecting block (15) are respectively fixedly arranged at the output ends of the two electric push rods (4) and slidably arranged at one side of the mounting seat (3); A lifting frame (16) is fixedly arranged on one side of the cutting frame (5), and a rectangular hole (23) is opened on one side of the lifting frame. A first guide groove (24) matching with the rectangular hole (23) is opened on the top of the first connecting block (14), and a second guide groove (25) matching with the rectangular hole (23) is opened on the top of the second connecting block (15), so as to drive the two cutting frames (5) to move away from each other when the electric push rod (4) is reset to avoid being stuck with the pipe (2).

5. The nickel-based special-shaped tube cold drawing forming process according to claim 3, characterized in that: A first guide rod (17) is fixedly arranged on the other side of the cutting frame (5); a waist-shaped hole (20) is opened on one side of the mounting plate (13); one end of the first guide rod (17) is slidably arranged in the waist-shaped hole (20); a limiting ring (18) is sleeved on the outer wall of the first guide rod (17); the limiting ring (18) is slidably arranged on one side of the mounting plate (13) through a sliding groove; and a first tension spring (19) is also sleeved on the outer wall of the first guide rod (17); two ends of the first tension spring (19) are respectively fixedly connected to the limiting ring (18) and the cutting frame (5).

6. The nickel-based special-shaped tube cold drawing forming process according to claim 3, characterized in that: A connecting frame (21) is fixedly arranged on the top of the lifting frame (16) located above. The connecting frame (21) is L-shaped, and the other end cooperates with one of the supporting frames (43). A second fixing block (37) is fixedly arranged on one side of the mounting seat (3), and a second gear (40) is rotatably arranged on the top of the second fixing block (37); a rack (41) meshing with the second gear (40) is fixedly arranged on the side of the two supporting frames (43) close to each other, so as to drive the two supporting frames (43) to approach each other.

7. The nickel-based special-shaped tube cold drawing forming process according to claim 5, characterized in that: Two first fixing blocks (36) are fixedly arranged on one side of the mounting seat (3), two second guide rods (38) are fixedly arranged between the first fixing block (36) and the second fixing block (37), and the support frame (43) is slidably sleeved on the second guide rods (38), and a second tension spring (39) is sleeved on the outer wall of one of the second guide rods (38), and two ends of the second tension spring (39) are respectively fixedly connected to the first fixing block (36) and the support frame (43) on one side close to each other.

8. The nickel-based special-shaped tube cold drawing forming process according to claim 6, characterized in that: A second clearance opening (44) is provided on the top of one of the first fixing blocks (36) for avoiding the moving path of the connecting frame (21).

9. The nickel-based special-shaped tube cold drawing forming process according to claim 2, characterized in that: The output end of the first motor (6) is sleeved with a positioning ring (22), which is fixedly arranged at the bottom of the cutting frame (5) and is used to axially position the pipe (2).

10. The nickel-based special-shaped tube cold drawing forming process according to any one of claims 2 to 8, characterized in that: The first cutting blade (7) and the second cutting blade (9) are made of YG8 hard alloy, and the specification of the first cutting blade (7) is Φ150×3 mm.

Images