Spinning device and spinning forming method for large-size elliptic curve generatrix thin-wall shell

Abstract

According to the spinning device and the spinning forming method for the large-size elliptic curve generatrix thin-wall shell, through the spinning device comprising a tailstock, a tail top, a spinning assembly, a spinning tire, an adapter disc and a main shaft, a powerful double-wheel numerical control spinning machine is used, a spinning blank is clamped at a time, two-pass spinning is conducted on a flat plate round blank, and the large-size elliptic curve generatrix thin-wall shell is obtained. And a spinning forming piece with machining allowance is obtained, turning machining is conducted on the spinning forming piece to remove the allowance, and the elliptic curve generatrix thin-wall shell is obtained. The spinning forming of the large-size stainless steel elliptical curved generatrix thin-wall shell is realized, and the problems that in the prior art, the large-size stainless steel elliptical curved generatrix thin-wall shell is poor in deep drawing forming stability and prone to instability and wrinkling, the clamping difficulty on a turning clamp is large, and the end face is prone to being uneven after turning cutting are solved.

Description

Technical Field

[0001] The present invention relates to a spinning device and a spinning forming method for a large-sized thin-walled shell with an elliptical curved busbar, belonging to the technical field of sheet metal forming. Background Art

[0002] The structure of the thin-walled shell is a rotating body combined with an elliptical curved busbar segment and a straight segment, which is a large-sized thin-walled part, and the ratio of the outer diameter of the straight cylinder segment to the thickness is ≥300. The thin-walled shell is formed by deep drawing. Due to its large diameter and small thickness, the forming stability is poor. During the deep drawing process of the blank, the tangential stress of the unformed flange part is relatively large, and it is easy to cause instability and wrinkling, and then rupture and scrapping. After the thin-walled shell is formed by deep drawing, due to its large diameter and small thickness, it is extremely easy to deform in the free state, and it is difficult to clamp on the turning fixture, which easily leads to uneven end faces after turning. At present, there is still a lack of means to achieve high-precision spinning processing. Summary of the Invention

[0003] The technical problem solved by the present invention is: aiming at the problems of poor forming stability, easy instability and wrinkling, difficult clamping on the turning fixture, and easy uneven end faces after turning of large-sized stainless steel thin-walled shells with elliptical curved busbars in the current existing technology, a spinning device and a spinning forming method for large-sized thin-walled shells with elliptical curved busbars are proposed.

[0004] The present invention solves the above technical problems through the following technical solutions:

[0005] A spinning device for a large-sized thin-walled shell with an elliptical curved busbar includes a tailstock, a tailstock center, a spinning assembly, a spinning mandrel, an adapter plate, and a main shaft. Among them:

[0006] The tailstock is arranged on the top of the spinning mandrel. The spinning blank for preparing the thin-walled shell is flatly placed and clamped on the top of the spinning mandrel through the tailstock center, and the tailstock center is pressurized through the tailstock to clamp the spinning blank. The spinning assembly for the spinning forming of the thin-walled shell is arranged on one side of the tailstock and drives the spinning blank to be spun through a spinning machine. The spinning mandrel is installed above the adapter plate, and the adapter plate is installed on the main shaft. The spinning assembly drives the spinning blank to be spun twice through the spinning machine, and the spinning blank becomes a thin-walled shell after two spins.

[0007] The spinning assembly includes a spinning wheel frame, a spinning wheel, and a spinning wheel seat. Among them:

[0008] The number of spinning wheel frames is two, which are connected to the output shafts at both ends of the spinning machine. A spinning wheel seat is installed on one side of the spinning wheel frame, and the spinning wheel is arranged on the spinning wheel seat. A turning tool holder is arranged on the other side of the spinning wheel frame, and a turning tool is arranged on the turning tool holder for cutting off the end face allowance of the thin-walled shell after spinning forming.

[0009] The thin-walled shell includes a straight cylinder segment and an elliptical curved busbar segment. Among them:

[0010] The straight cylinder section is connected to and integrally formed with the elliptical curved mother line section. The first spinning process is used to prepare the elliptical curved mother line section; the second spinning process is used to prepare the straight line section and obtain the completed thin-walled shell. After the thin-walled shell is formed, a turning tool is used for turning to remove the end face allowance.

[0011] The diameter-to-thickness ratio of the spinning blank is determined according to the forming requirements of the thin-walled shell. The spinning blank is made of stainless steel and is in the shape of a circular plate. The outer surface of the spinning mandrel is consistent with the inner surface specified by the forming requirements of the thin-walled shell. After the spinning blank is fixed by the tailstock, it is centered and aligned at the top of the spinning mandrel before processing.

[0012] During the spinning process, the main shaft is used to drive the assembled adapter plate, spinning mandrel, spinning blank, and tailstock to rotate coaxially. During the rotation, the spinning blank is subjected to two spinning processes.

[0013] A spinning forming method implemented according to a spinning device for a large-size thin-walled shell with an elliptical curved mother line includes:

[0014] Install the spinning mandrel on the adapter plate and install the adapter plate on the main shaft;

[0015] Install the spinning wheel on the spinning wheel seat, install the spinning wheel seat on one side of the spinning wheel frame, and install a turning tool and a turning tool holder on the other side of the spinning wheel frame;

[0016] Install the tailstock on the tailstock seat, prepare a spinning blank according to the preparation requirements of the thin-walled shell, and clamp it on the spinning mandrel through the tailstock;

[0017] Install the spinning blank on the spinning mandrel. After centering and alignment, apply pressure from the tailstock seat to the tailstock to ensure that the tailstock and the spinning mandrel clamp the spinning blank;

[0018] Conduct the first spinning process on the elliptical curved mother line section;

[0019] Conduct the second spinning process on the straight line section;

[0020] After the spinning process is completed, obtain a rough blank of the thin-walled shell with end face allowance. While maintaining the clamping pressure from the tailstock seat to the tailstock, use a turning tool for turning to remove the end face allowance of the thin-walled shell and obtain a thin-walled shell with a thickness that meets the preparation requirements of the thin-walled shell.

[0021] During the first spinning process, the shear spinning method is adopted. The spinning gap for the first 3 / 4 section of the elliptical curved mother line section is determined according to the thickness of the spinning blank, the half-cone angle of the spinning mandrel, and the retraction amount of the spinning machine; the spinning gap for the last 1 / 4 section of the elliptical curved mother line section is determined according to the thickness of the spinning blank and the retraction amount of the spinning machine, without considering the half-cone angle of the spinning mandrel.

[0022] During the first spinning process, when the spinning gap is within the preset range of the spinning bus length, the adjustment of the spinning gap is achieved through a uniform transition change; the preset range of the spinning bus length is determined after calculation according to the preparation requirements of the thin-walled shell.

[0023] During the second spinning process, two passes of spinning are adopted. The spinning gap of the first pass of spinning is determined according to the thickness of the spinning blank and the retraction amount of the spinning machine, and the spinning gap of the second pass of spinning is determined according to the thickness required for the preparation of the thin-walled shell and the retraction amount of the spinning machine.

[0024] After using a turning tool to cut off the end face allowance of the thin-walled shell, the wall thickness of the thin-walled shell is monitored. If the thickness value meets the requirements for the preparation of the thin-walled shell, the preparation is completed, the tailstock is removed, and the thin-walled shell is taken out. Otherwise, the current preparation fails, the tailstock and the thin-walled shell are removed, and the preparation is carried out again.

[0025] The advantages of the present invention compared with the prior art are as follows:

[0026] (1) A spinning device and a spinning forming method for a large-size elliptical curved bus thin-walled shell provided by the present invention use a powerful double-wheel numerical control spinning machine. The spinning blank is only clamped once, and a spinning wheel is installed through a spinning wheel seat and a spinning wheel frame on one side, and two passes of spinning are continuously carried out to obtain a thin-walled shell with machining allowance. Different spinning gaps are adopted in the two passes of spinning, which solves the problems of poor stability in the deep drawing forming of thin-walled shells and easy occurrence of instability and wrinkling. By installing a turning tool holder and a turning tool on the spinning wheel frame on the other side, the thin-walled shell is machined on the spinning mandrel to cut the end face, avoiding the problems of difficult clamping on the turning fixture and easy unevenness of the end face after turning.

[0027] (2) Compared with the deep drawing forming method, the forming method of the thin-walled shell by spinning adopted in the present invention has good surface quality of the thin-walled shell formed by spinning, the surface is smooth without wrinkles. At the same time, after the thin-walled shell is formed by spinning, the allowance is directly removed by turning without secondary clamping, which ensures the turning accuracy, avoids the problem of difficult alignment in secondary clamping, and obtains a thin-walled shell with specified height and diameter dimensions by cutting the allowance of the straight section of the thin-walled shell. Description of the Drawings

[0028] Figure 1 is a schematic structural diagram of the thin-walled shell provided by the present invention;

[0029] Figure 2 is a schematic structural diagram of the spinning blank of the thin-walled shell provided by the present invention;

[0030] Figure 3 is a schematic diagram of the process preparation before the thin-walled shell is formed by spinning provided by the present invention;

[0031] Figure 4It is a schematic diagram of the spinning forming of a thin-walled shell provided by the present invention;

[0032] Figure 5 It is a schematic diagram of the turning machining of a thin-walled shell provided by the present invention. Specific embodiments

[0033] A spinning device and a spinning forming method for a large-sized thin-walled shell with an elliptical curved generatrix. Through a spinning device including a tailstock, a tailstock center, a spinning assembly, a spinning mandrel, an adapter plate, and a main shaft, a powerful double-wheel numerical control spinning machine is used. The spinning blank is clamped once, and the flat circular blank is spun in two passes to obtain a spun formed part with machining allowance. The allowance of the spun formed part is removed by turning machining to obtain a thin-walled shell with an elliptical curved generatrix. It realizes the spinning forming of a large-sized stainless steel thin-walled shell with an elliptical curved generatrix, and solves the problems in the prior art such as poor stability in the drawing forming of a large-sized stainless steel thin-walled shell with an elliptical curved generatrix, easy occurrence of instability and wrinkling, great difficulty in clamping on a turning fixture, and easy unevenness of the end face after turning.

[0034] In the spinning device, the tailstock is arranged on the top of the spinning mandrel. The spinning blank for preparing the thin-walled shell is flatly laid and clamped on the top of the spinning mandrel through the tailstock center, and the tailstock center is pressurized through the tailstock to clamp the spinning blank; the spinning assembly for the spinning forming of the thin-walled shell is arranged on one side of the tailstock and spins the spinning blank through the drive of the spinning machine; the spinning mandrel is installed above the adapter plate, and the adapter plate is installed on the main shaft; the spinning assembly spins the spinning blank twice respectively through the drive of the spinning machine, and the spinning blank becomes a thin-walled shell after two spins.

[0035] The spinning assembly includes a spinning wheel frame, a spinning wheel, and a spinning wheel seat, where:

[0036] The number of spinning wheel frames is two, which are connected to the output shafts at both ends of the spinning machine. A spinning wheel seat is installed on one spinning wheel frame, and the spinning wheel is arranged on the spinning wheel seat; a turning tool holder is arranged on the other spinning wheel frame, and a turning tool is arranged on the turning tool holder for removing the end face allowance of the thin-walled shell after spinning forming.

[0037] The thin-walled shell includes a straight cylinder section and an elliptical curved generatrix section, where:

[0038] The straight cylinder section is connected and integrally formed with the elliptical curved generatrix section. The first spinning forming is used to prepare the elliptical curved generatrix section; the second spinning forming is used to prepare the straight section and obtain the completed thin-walled shell; after the thin-walled shell is formed, it is turned by a turning tool to remove the end face allowance.

[0039] The ratio of the diameter to the thickness of the spinning blank is determined according to the forming requirements of the thin-walled shell. The spinning blank is made of stainless steel and is in a circular plate configuration; the outer shape surface of the spinning mandrel is consistent with the inner shape surface specified by the forming requirements of the thin-walled shell; after the spinning blank is fixed by the tailstock, it is centered and aligned on the top of the spinning mandrel for machining.

[0040] During the spinning process, the main shaft is used to drive the adapter plate, spinning mandrel, spinning blank, and tailstock to rotate coaxially after assembly. During the rotation process, the spinning blank is subjected to two spinning treatments.

[0041] The spinning forming method realized by the spinning device for large-size elliptical curved generatrix thin-walled shells includes:

[0042] Install the spinning mandrel on the adapter plate and install the adapter plate on the main shaft;

[0043] Install the spinning wheel on the spinning wheel seat, install the spinning wheel seat on one side of the spinning wheel frame, and install the turning tool and turning tool holder on the other side of the spinning wheel frame;

[0044] Install the tailstock on the tailstock seat, prepare the spinning blank according to the requirements for preparing the thin-walled shell, and clamp it on the spinning mandrel through the tailstock;

[0045] Install the spinning blank on the spinning mandrel. After centering and alignment, apply pressure to the tailstock to the tailstock to ensure that the tailstock and the spinning mandrel clamp the spinning blank;

[0046] Conduct the first spinning process on the elliptical curved generatrix section;

[0047] Conduct the second spinning process on the straight section;

[0048] After the spinning process is completed, obtain a rough blank of the thin-walled shell with end face allowance. Under the condition of maintaining the clamping pressure of the tailstock to the tailstock, use the turning tool to cut to remove the end face allowance of the thin-walled shell and obtain a thin-walled shell with a thickness that meets the requirements for preparing the thin-walled shell.

[0049] During the first spinning process, the shear spinning method is adopted. The spinning gap for the first 3 / 4 section of the elliptical curved generatrix section is determined according to the thickness of the spinning blank, the semi-cone angle of the spinning mandrel, and the retraction amount of the spinning machine; the spinning gap for the last 1 / 4 section of the elliptical curved generatrix section is determined according to the thickness of the spinning blank and the retraction amount of the spinning machine, without considering the semi-cone angle of the spinning mandrel.

[0050] During the first spinning process, when the spinning gap is within the preset range of the spinning generatrix length, the adjustment of the spinning gap is realized through a uniform transition change; the preset range of the spinning generatrix length is determined after calculation according to the requirements for preparing the thin-walled shell.

[0051] During the second spinning process, two-pass spinning is adopted. The spinning gap for the first pass of spinning is determined according to the thickness of the spinning blank and the retraction amount of the spinning machine, and the spinning gap for the second pass of spinning is determined according to the thickness required for preparing the thin-walled shell and the retraction amount of the spinning machine.

[0052] After using a turning tool to cut the end face allowance of the thin-walled shell and then monitoring the wall thickness of the thin-walled shell, if the thickness value meets the requirements for preparing the thin-walled shell, the preparation is completed, the tailstock is removed, and the thin-walled shell is taken out; otherwise, the current preparation fails, the tailstock and the thin-walled shell are removed, and the preparation is carried out again.

[0053] The following is a further description in conjunction with the accompanying drawings of the specification and preferred embodiments:

[0054] In the current embodiment, a method for spin forming a large-sized stainless steel elliptical curved generatrix thin-walled shell, as Figure 1 shown, the thin-walled shell includes a straight cylinder section and an elliptical curved generatrix section connected to the straight cylinder section, and comprises the following steps:

[0055] (1) Prepare a spin blank, the spin blank is a stainless steel thin-walled circular plate, and is clamped on the spin chuck through a tailstock;

[0056] (2) Adopt a powerful double-wheel CNC spin press, install a spinning wheel through a spinning wheel seat and a spinning wheel frame on one side, start from the bottom of the spin blank, carry out the first pass of spinning, complete the forming of the elliptical curved generatrix section and the preliminary forming of the straight section, obtain a preliminarily formed thin-walled shell, and then start from the intersection of the straight section and the elliptical curved generatrix section of the thin-walled shell, carry out the second pass of spinning, and complete the forming of the straight section to obtain a completely formed thin-walled shell;

[0057] As Figure 3 shown, the powerful double-wheel CNC spin press includes a tailstock 1, a tailstock center 2, a spinning wheel seat 3, a spinning wheel frame 4, a spinning wheel 5, a spin chuck 7, an adapter plate 8, and a main shaft 9. As Figure 4 shown, when the thin-walled shell is spin formed, the spinning wheel 5 moves along the spinning wheel path 10, and the spin blank 6 is deformed by force to become a thin-walled shell 11 with machining allowance.

[0058] (3) Install a tool rest and a turning tool on the spinning wheel frame on the other side of the powerful double-wheel CNC spin press, and cut the allowance of the straight section of the thin-walled shell to obtain a thin-walled shell with specified height and diameter dimensions;

[0059] As Figure 5 shown, the powerful double-wheel CNC spin press has two spinning wheel frames 4, a spinning wheel seat 3 and a spinning wheel 5 are installed on one spinning wheel frame 4, a turning tool 12 and a tool rest 13 are installed on the other spinning wheel frame 4, and the turning tool 12 cuts off the end face allowance of the thin-walled shell 11.

[0060] A spinning forming method for a large-sized stainless steel thin-walled shell with an elliptical curved generatrix provided by the present invention uses a powerful double-wheel numerical control spinning machine. The spinning blank is only clamped once. A spinning wheel is installed through a spinning wheel seat and a spinning wheel frame on one side, and two passes of spinning are continuously carried out to obtain a thin-walled shell with machining allowance. Different spinning clearances are adopted in the two passes of spinning, which solves the problems of poor stability in the drawing forming of the thin-walled shell and easy occurrence of instability and wrinkling. By installing a turning tool holder and a turning tool on the spinning wheel frame on the other side, the end face of the thin-walled shell is turned on the spinning mandrel, avoiding the problems of difficult clamping on the turning fixture and easy unevenness of the end face after turning.

[0061] In an optional embodiment, the thin-walled shell preferably has an outer diameter of 600 mm to 1200 mm and a height of 40 mm to 120 mm for the straight cylinder section, an outer diameter of 200 mm to 400 mm for the small end of the elliptical curved generatrix section, a generatrix length of 350 mm to 700 mm, and a semi-cone angle of 0° to 90°.

[0062] In an optional embodiment, in step (1), the thickness t0 of the spinning blank 6 is t0≥1.5 mm, and the ratio D / t0 of the diameter D to the thickness t0 is D / t0≥300.

[0063] In an optional embodiment, in step (1), the spinning blank 6 is clamped on the spinning mandrel 7 through the tailstock 2.

[0064] In an optional embodiment, in step (2), a powerful double-wheel numerical control spinning machine is used. A spinning wheel 5 is installed through a spinning wheel seat 3 and a spinning wheel frame 4 on one side. Starting from the bottom of the spinning blank 6, the first pass of spinning is carried out to complete the forming of the elliptical curved generatrix section and the preliminary forming of the straight section, obtaining a preliminarily formed thin-walled shell 11. Then, starting from the intersection of the straight section and the elliptical curved generatrix section of the thin-walled shell 11, the second pass of spinning is carried out to complete the forming of the straight section, obtaining a completely formed thin-walled shell 11.

[0065] In an optional embodiment, in step (3), a turning tool holder 13 and a turning tool 12 are installed on the spinning wheel frame 4 on the other side of the powerful double-wheel numerical control spinning machine to turn the allowance of the straight section of the thin-walled shell 11, obtaining a thin-walled shell 11 with a specified height dimension.

[0066] The following are specific embodiments of the present invention:

[0067] Embodiment 1

[0068] This embodiment provides a certain type of thin-walled shell, the material of which is stainless steel 06Cr19Ni10, and the structure is as Figure 1As shown, the thin-walled shell includes a straight cylinder section and an elliptical curved generatrix section connected to the straight cylinder section. The outer diameter Φ2 of the straight cylinder section is 760 mm, the height L1 of the straight cylinder section is 47.5 mm, the outer diameter Φ1 of the small end of the elliptical curved generatrix section is 145.5 mm, the length L2 of the elliptical curved generatrix section is 473 mm, the semi-cone angle α is 0° to 90°, and the thickness t of the thin-walled shell is 1.0 mm - 2.0 mm. Its forming method includes:

[0069] (1) Spin-forging blank 6, the material is stainless steel 06Cr19Ni10, as Figure 2 shown, the structure of the spin-forging blank 6 is a circular plate, the diameter D is 1000 mm, and the thickness t0 is 2 mm.

[0070] (2) Install the spin-forging mandrel 7 on the adapter plate 8, and then install the adapter plate 8 on the main shaft 9. Among them, the outer profile surface of the spin-forging mandrel 7 is consistent with the inner profile surface of the thin-walled shell.

[0071] (3) Install the spinning wheel 5 on the spinning wheel seat 3, and then install the spinning wheel seat 3 on one side of the spinning wheel frame 4. Install the turning tool 12 and the turning tool holder 13 on the other side of the spinning wheel frame 4.

[0072] (4) Install the tailstock center 2 on the tailstock 1.

[0073] (5) Install the spin-forging blank 6 on the spin-forging mandrel 7. After centering and alignment, the tailstock 1 applies a pressure of 100 kN to the tailstock center 2 to make the tailstock center 2 and the spin-forging mandrel 7 clamp the spin-forging blank 6.

[0074] (6) The main shaft 9 rotates, driving the adapter plate 8, the spin-forging mandrel 7, the spin-forging blank 6, and the tailstock center 2 to rotate coaxially together, and the rotation speed is 100 revolutions per minute. The tailstock 1 always maintains a pressure of 100 kN applied to the tailstock center 2.

[0075] (7) The first 3 / 4 section of the elliptical curved generatrix section L2 is carried out in the way of shear spinning. The spinning gap ≈ the thickness t0 of the spin-forging blank × sin(semi-cone angle α) - the machine tool retraction amount. The spinning gap of the last 1 / 4 section of the elliptical curved generatrix section L2 ≈ (0.4 - 0.6) × the thickness t0 of the spin-forging blank - the machine tool retraction amount. At the intersection of the first 3 / 4 section and the 1 / 4 section of the elliptical curved generatrix section L2, the spinning gap gradually changes in the range of about 20 mm - 40 mm of the generatrix length.

[0076] (8) The straight cylinder section L1 is spun in two passes. The spinning gap of the first pass ≈ (0.4 - 0.6) × the thickness t0 of the spin-forging blank - the machine tool retraction amount. The spinning gap of the second pass ≈ the thickness t of the thin-walled shell - the machine tool retraction amount.

[0077] (9) After the spinning of the elliptical curved generatrix section L2 and the straight cylinder section L1 is completed, a thin-walled shell 11 with machining allowance is obtained, and the tailstock 1 maintains a pressure of 100 kN applied to the tailstock center 2.

[0078] (10) The turning tool 12 turns and removes the end face allowance of the thin-walled shell 11, obtaining the thin-walled shell 11 with a height H of 433 mm.

[0079] The thin-walled shell forming method provided in this embodiment, compared with the deep drawing forming method:

[0080] (1) The surface quality of the thin-walled shell by spinning forming is good, with a smooth surface and no wrinkles.

[0081] (2) After the thin-walled shell is formed by spinning, the allowance is directly removed by turning, without secondary clamping, ensuring the turning accuracy and avoiding the problem of difficult alignment in secondary clamping.

[0082] Embodiment 2

[0083] This embodiment provides a certain type of thin-walled shell, with the material being stainless steel 06Cr19Ni10, and the structure is as Figure 1 shown. The thin-walled shell includes a straight cylinder section and an elliptical curved mother line section connected to the straight cylinder section. The outer diameter Φ2 of the straight cylinder section is 1040 mm, the height L1 of the straight cylinder section is 90 mm, the outer diameter Φ1 of the small end of the elliptical curved mother line section is 400 mm, the length L2 of the elliptical curved mother line section is 620 mm, the semi-cone angle α is 0° to 90°, and the thickness t of the thin-walled shell is 1.0 mm - 2.0 mm. Its forming method includes:

[0084] (1) The spinning blank 6, with the material being stainless steel 06Cr19Ni10, is as Figure 2 shown. The structure of the spinning blank 6 is a circular plate, with a diameter D of 1350 mm and a thickness t0 of 2 mm.

[0085] (2) Install the spinning mandrel 7 on the adapter plate 8, and then install the adapter plate 8 on the main shaft 9. Among them, the outer profile surface of the spinning mandrel 7 is consistent with the inner profile surface of the thin-walled shell.

[0086] (3) Install the spinning wheel 5 on the spinning wheel seat 3, and then install the spinning wheel seat 3 on one side of the spinning wheel frame 4. Install the turning tool 12 and the turning tool rest 13 on the other side of the spinning wheel frame 4.

[0087] (4) Install the tailstock center 2 on the tailstock 1.

[0088] (5) Install the spinning blank 6 on the spinning mandrel 7. After centering and alignment, the tailstock 1 applies a pressure of 100 kN to the tailstock center 2, so that the tailstock center 2 and the spinning mandrel 7 clamp the spinning blank 6.

[0089] (6) The main shaft 9 rotates, driving the adapter plate 8, the spinning mandrel 7, the spinning blank 6, and the tailstock center 2 to rotate coaxially together, with a rotation speed of 100 revolutions per minute. The tailstock 1 always maintains a pressure of 100 kN applied to the tailstock center 2.

[0090] (7) The first 3 / 4 of the elliptical curved mother line segment L2 is processed by shear spinning. The spinning gap ≈ the thickness t0 of the spinning blank × sin(half cone angle α) - the retraction amount of the machine tool. The spinning gap of the last 1 / 4 of the elliptical curved mother line segment L2 ≈ (0.4 - 0.6) × the thickness t0 of the spinning blank - the retraction amount of the machine tool. At the intersection of the first 3 / 4 and the last 1 / 4 of the elliptical curved mother line segment L2, the spinning gap gradually changes within the range of about 20 mm - 40 mm of the bus length.

[0091] (8) The straight cylinder segment L1 is spun in two passes. The spinning gap of the first pass of spinning ≈ (0.4 - 0.6) × the thickness t0 of the spinning blank - the retraction amount of the machine tool. The spinning gap of the second pass of spinning ≈ the thickness t of the thin-walled shell - the retraction amount of the machine tool.

[0092] (9) After the spinning of the elliptical curved mother line segment L2 and the straight cylinder segment L1 is completed, a thin-walled shell 11 with machining allowance is obtained, and the tailstock 1 is kept applying a pressure of 100 kN to the tailstock 2.

[0093] (10) The turning tool 12 cuts off the end face allowance of the thin-walled shell 11 to obtain a thin-walled shell 11 with a height H of 600 mm.

[0094] The thin-walled shell forming method provided in this embodiment compared with the deep drawing forming method:

[0095] (1) The surface quality of the thin-walled shell formed by spinning is good, and the surface is smooth without wrinkles.

[0096] (2) After the thin-walled shell is formed by spinning, the allowance is directly cut off by turning without secondary clamping, which ensures the turning accuracy and avoids the problem that it is difficult to align during secondary clamping. Although the present invention has been disclosed above with preferred embodiments, it is not used to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modification, equivalent change and decoration made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention all belong to the protection scope of the technical solution of the present invention.

[0097] The content not described in detail in the specification of the present invention belongs to the well-known technology of those skilled in the art.

Claims

1. A large-size elliptical curved generatrix thin-wall shell spinning device, characterized in that: It includes tailstock, tail top, spinning assembly, spinning tire, adapter plate, spindle, among which: The tailstock is arranged on the top of the spinning tire, and the spun blank for preparing the thin-walled shell is clamped on the top of the spinning tire by the tail top, and the tail top is pressurized by the tailstock to clamp the spun blank; the spinning assembly for spinning the thin-walled shell is arranged on one side of the tailstock, and the spun blank is driven by the spinning machine to be spun; the spinning tire is installed above the adapter plate, and the adapter plate is installed on the main shaft; the spinning assembly is driven by the spinning machine to spin the spun blank twice, and the spun blank becomes a thin-walled shell after two spinning.

2. A large-size elliptical curved generatrix thin-wall shell spinning device according to claim 1, characterized in that: The spinning assembly comprises a spinning wheel frame, a spinning wheel, and a spinning wheel seat, wherein: There are two rotating wheel frames, which are connected to the output shafts at both ends of the spinning machine. A rotating wheel seat is installed on one side of the rotating wheel frame, and a rotating wheel is set on the rotating wheel seat; a turning tool holder is arranged on the other side of the rotating wheel frame, and a turning tool is arranged on the turning tool holder for cutting off the end face excess of the thin-walled shell after spinning.

3. A large-size elliptical curved generatrix thin-wall shell spinning device according to claim 2, characterized in that: The thin-walled shell includes a straight tube segment and an elliptical curved generatrix segment, wherein: The straight tube section is connected to the elliptical curved mother line section and is prepared as a whole. The first spinning forming is used to prepare the elliptical curved mother line section; the second spinning forming is used to prepare the straight section and obtain the completed thin-walled shell; after the thin-walled shell is formed, it is turned by a turning tool to remove the end face excess.

4. The large-size elliptical curved generatrix thin-wall shell spinning device according to claim 1 is characterized in that: The diameter-thickness ratio of the spinning blank is determined according to the thin-wall shell forming requirements. The spinning blank is made of stainless steel and has a circular plate configuration. The outer surface of the spinning tire is consistent with the inner surface specified by the thin-wall shell forming requirements. The spun blank is fixed by the tailstock and then aligned on the top of the spun tire before processing.

5. A large-size elliptical curved generatrix thin-wall shell spinning device according to claim 4, characterized in that: During the spinning process, the main shaft is used to drive the assembled adapter plate, the spinning tire, the spinning blank, and the tail top to rotate coaxially, and the spinning blank is spun twice during the rotation process.

6. A spinning forming method implemented by the spinning device for a large-size elliptical curved generatrix thin-walled shell according to claim 5, characterized in that include: Install the spinning tire on the adapter plate, and install the adapter plate on the main shaft; Install the rotary wheel on the rotary wheel seat, install the rotary wheel seat on one side of the rotary wheel frame, and install the turning tool and the turning tool holder on the other side of the rotary wheel frame; The tail top is installed on the tailstock, and the spinning blank is prepared according to the thin-wall shell preparation requirements, and is clamped on the spinning tire through the tail top; Install the spinning blank on the spinning tire, and after centering and aligning, apply pressure to the tail top through the tailstock to ensure that the tail top and the spinning tire clamp the spinning blank; Perform the first spinning process on the elliptical curved generatrix segment; Perform a second spinning process on the straight line segment; After the spinning process is completed, a rough thin-walled shell with end face allowance is obtained. While maintaining the clamping pressure of the tailstock to the tail top, a turning tool is used to cut to remove the end face allowance of the thin-walled shell to obtain a thin-walled shell with a thickness that meets the thin-walled shell preparation requirements.

7. The spin forming method according to claim 6, characterized in that: During the first spinning process, a shear spinning method is adopted, and the spinning gap of the first 3 / 4 of the elliptical curved main line segment is determined according to the thickness of the spinning blank, the semi-cone angle of the spinning tire, and the allowance of the spinning machine; the spinning gap of the last 1 / 4 of the elliptical curved main line segment is determined according to the thickness of the spinning blank and the allowance of the spinning machine, without considering the semi-cone angle of the spinning tire.

8. The spin forming method according to claim 7, characterized in that: During the first spinning process, when the spinning gap is within the preset range of the spinning generatrix length, the spinning gap is adjusted by uniform transition change; the preset range of the spinning generatrix length is determined after calculation based on the thin-walled shell preparation requirements.

9. The spin forming method according to claim 8, characterized in that: During the second spinning process, two passes of spinning are used. The spinning gap of the first pass is determined according to the thickness of the spinning blank and the allowance of the spinning machine, and the spinning gap of the second pass of spinning is determined according to the thickness required for the preparation of the thin-walled shell and the allowance of the spinning machine.

10. The spin forming method according to claim 9, characterized in that: After using a turning tool to remove the end face excess of the thin-walled shell, the wall thickness of the thin-walled shell is monitored. If the thickness value meets the thin-walled shell preparation requirements, the preparation is completed, the tail top is removed and the thin-walled shell is taken out. Otherwise, the current preparation fails, the tail top and the thin-walled shell are removed and re-prepared.

Images