Manufacturing method of large thin-walled cylinder
By using specialized sleeve tooling and yellow sand support, the deformation problem of large thin-walled cylinders during precision machining of stepped inner holes was solved, achieving high-precision machining and easy operation.
Patent Information
- Application Number
- CN202511898533.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-16
- Publication Date
- 2026-02-10
AI Technical Summary
Large thin-walled cylinders are prone to deformation when precision machining stepped inner holes. Existing clamping methods are cumbersome and cannot guarantee high precision.
By using a special sleeve tooling and yellow sand support, the cutting force is evenly dispersed by the combination of clamping plates, sleeves and pressure plates, and the outer wall of the cylinder is stably supported. The stepped inner hole is then finished on a vertical lathe.
It effectively reduces cylinder deformation, improves the machining accuracy and ease of operation of the stepped inner hole, and ensures the stability of the cylinder shape.
Smart Images
Figure CN121491682A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of cylinder manufacturing technology, and in particular to a method for manufacturing large thin-walled cylinders. Background Technology
[0002] There is a type of large thin-walled cylinder, such as Figure 1 As shown, the outer diameter of the cylinder is 884 mm. The middle part of the cylinder has a stepped inner hole, which consists of a large diameter section and two small diameter sections. The two small diameter sections are located on both sides of the large diameter section. The diameter of the small diameter section is 864 mm and the diameter of the large diameter section is 866 mm. The openings at both ends of the stepped inner hole are chamfered at 45°. There are 12 screw holes evenly opened on each of the two end faces of the cylinder.
[0003] When precision machining the stepped inner hole of this large thin-walled cylinder, the high precision required for the stepped inner hole means that using only a conventional chuck to clamp the outer diameter of the cylinder will cause outward deformation due to the thin wall, failing to meet the high precision requirements. While a custom-made sleeve mold with an inner diameter matching the outer diameter of the cylinder can improve the machining accuracy of the stepped inner hole, ensuring effective support requires a slight interference fit or transition fit between the mold and the outer diameter of the cylinder. Assembly requires a press, which is not only cumbersome but also carries a high risk of bending the cylinder. Furthermore, disassembling the mold after machining is difficult, as it may scratch the outer surface of the cylinder or cause new deformation.
[0004] Therefore, this invention proposes a method for manufacturing large thin-walled cylinders to solve the above-mentioned problems. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to provide a method for manufacturing large thin-walled cylinders, thereby improving the machining accuracy of the cylinders.
[0006] To solve the above-mentioned technical problems, the technical solution of the present invention is: a method for manufacturing a large thin-walled cylinder, the innovation of which lies in: including the following steps: S1. Cylinder body manufacturing: The plates are cut, rolled, and welded longitudinally to form the cylinder body. The welds on the cylinder body are ground smooth. After the welds pass the inspection, the cylinder body is rounded and subjected to overall solution heat treatment. S2. Rough turning: Using a vertical lathe, turn the right end face of the cylinder body, rough turn the inner hole of the cylinder body, turn the left end face of the cylinder body, and turn the outer circle of the cylinder body in sequence. After natural aging until the residual stress is eliminated, perform a second annealing heat treatment. S3, Semi-finish turning: First, use a vertical lathe to finish the right end face of the cylinder, then semi-finish turn the inner hole of the cylinder, and then turn the outer circle of the cylinder to the desired position; S4. Precision turning: Fix the cylinder body inside the special sleeve fixture, and evenly fill the space between the cylinder body and the special sleeve fixture with yellow sand in the circumferential direction. The pressure plate of the special sleeve fixture is fixed on the chuck of the vertical lathe using a threaded rod. With the right end face of the cylinder body facing up, after correcting the inner hole of the cylinder body, turn the stepped inner hole of the cylinder body into place. Chamfer the right end opening and the left end opening of the stepped inner hole of the cylinder body into place respectively. S5. Machining: Remove the cylinder body from the special sleeve tooling, support the inner hole of the cylinder body with a special support tooling, measure and correct the roundness of the cylinder body with a micrometer, drill the inner holes of the screw holes on both sides of the cylinder body and then tap the threads.
[0007] Further, the rough turning process of S2 is as follows: place the cylinder body on the worktable of the vertical lathe with the right end face facing up, clamp the outer circle of the cylinder body with a chuck, and after correction, turn the right end face of the cylinder body to a roughness of Ra6.3; then rough turn the inner hole of the cylinder body, leaving a margin in the inner hole; then turn the cylinder body 180° so that the left end face of the cylinder body faces up, use a clamp to tighten and fix the inner hole of the cylinder body, turn the left end face of the cylinder body, leaving a margin in the axial length of the cylinder body, turn the outer circle of the cylinder body, leaving a margin in the outer circle of the cylinder body; after natural aging for 72 hours, perform a second annealing heat treatment.
[0008] Furthermore, the semi-finish turning process of S3 is as follows: Place the cylinder body on the worktable of the vertical lathe with the right end face facing up. After clamping and correcting the outer circle of the cylinder body using a chuck, the right end face of the cylinder body is finished. After rotating the cylinder body 180°, place it on the chuck level block with the left end face facing up. Use a chuck plate to press the left end face of the cylinder body from the outside and semi-finish turn the inner hole of the cylinder body, leaving a margin in the inner hole. After rotating the cylinder body 180°, place it on the chuck level block with the right end face facing up. Use a chuck plate to press the right end face of the cylinder body from the inside and turn the outer circle of the cylinder body to the desired position.
[0009] Furthermore, the special sleeve tooling includes a clamping plate, a sleeve, and a pressure plate; A stepped hole is opened in the middle of the clamping plate. The stepped hole includes an upper hole section and a lower hole section. The diameter of the upper hole section is larger than the inner diameter of the cylinder, and the diameter of the lower hole section is smaller than the inner diameter of the cylinder. Several countersunk holes penetrating the clamping plate are evenly opened along the circumferential direction on the outer side of the stepped hole on the clamping plate. The sleeve is coaxially fixed to the top surface of the clamping plate. The inner radius of the sleeve is larger than the outer radius of the cylinder, and the difference between the inner radius of the sleeve and the outer radius of the cylinder is at least 4 times the wall thickness of the cylinder. The wall thickness of the sleeve is at least 2 times the wall thickness of the cylinder. The pressure plate is coaxially placed above the sleeve. A through hole is opened in the middle of the pressure plate. The diameter of the through hole is larger than the inner diameter of the cylinder and smaller than the outer diameter of the cylinder. The bottom of the pressure plate has an integrally formed limiting ring protrusion. The inner diameter of the limiting ring protrusion matches the outer diameter of the cylinder. The outer diameter of the limiting ring protrusion is smaller than the inner diameter of the sleeve. Several connecting holes for the threaded rod to pass through are evenly opened along the circumferential direction on the outside of the through hole on the pressure plate.
[0010] Furthermore, the precision turning operation process of S4 is as follows: First, use a special support fixture to support the inner hole of the cylinder body. Use a micrometer to measure and correct the roundness of the cylinder body. Drill some threaded holes on both sides of the cylinder body and then tap them to form threaded holes that correspond one-to-one with each countersunk hole. After tapping, remove the special support fixture. Then, place the special sleeve fixture on the worktable of the vertical lathe. After the position is corrected, put the cylinder body into the sleeve and support it with the top surface of the clamping plate. With the right end face of the cylinder body facing upward, use screws to pass through the countersunk holes from the bottom of the clamping plate and thread them into the corresponding threaded holes on the cylinder body to complete the positioning and fixing of the cylinder body. A circular groove is formed between the cylinder body and the sleeve. Pour yellow sand evenly and slowly into the circular groove along the circumference until the top surface of the yellow sand is flush with the top surface of the sleeve. Then, press the pressure plate on the right end face of the cylinder body. At the same time, make the threaded rods that were previously installed on the worktable of the vertical lathe pass through the corresponding connecting holes of the pressure plate. Install nuts on each threaded rod and tighten them. The stepped inner hole of the cylinder body is in place. The right and left ends of the stepped inner hole of the cylinder body are chamfered in place.
[0011] Furthermore, the special support fixture includes a circular base plate and several correction components evenly distributed along the circular base plate; The correction assembly includes a hexagon socket head cap screw, a nut, a washer, and a nylon shock-absorbing sleeve. The washer is fixedly connected to the top surface of the circular base plate, the nut is fixed to the top surface of the washer, and the hexagon socket head cap screw is threaded into the nut. The central axes of several hexagon socket head cap screws in the correction assembly are on the same plane and all intersect perpendicularly with the central axis of the circular base plate. The nylon shock-absorbing sleeve is located on the side of the nut away from the central axis of the circular base plate. The nylon shock-absorbing sleeve has a threaded groove that matches the hexagon socket head cap screw, and the end of the hexagon socket head cap screw is threaded into the threaded groove.
[0012] The advantages of this invention are: In the manufacturing method of this invention, when finishing the stepped inner hole of the cylinder, yellow sand is poured into the outer side of the cylinder to support the outer wall of the cylinder. The filling of yellow sand can not only evenly disperse the stress generated during finishing, reduce the local deformation caused by cutting force, and maintain the stability of the cylinder shape, but also increase the overall mass and damping of the tooling, effectively absorb vibration, and make the cutting process more stable, thereby ensuring the machining accuracy of the stepped inner hole of the cylinder.
[0013] The special sleeve fixture of this invention optimizes the shape and size of the sleeve, clamping plate, and pressure plate. When the cylinder body is installed inside the fixture, the clamping plate uses countersunk holes and screws to position and fix the bottom of the cylinder body, and reserves space for chamfering at the left end of the inner hole at the bottom of the cylinder body. The pressure plate presses on the top of the cylinder body and uses the protruding limiting ring to position the top of the cylinder body. At the same time, it reserves space for chamfering at the right end of the inner hole at the top of the cylinder body. This allows the stepped inner hole and chamfering at both ends of the cylinder body to be completed in one clamping operation, which is convenient. The size design of the sleeve can effectively ensure the bearing strength and deformation resistance of the sleeve itself, and ensure that the amount of yellow sand poured between the sleeve and the cylinder body has sufficient support and vibration absorption capacity. Attached Figure Description
[0014] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0015] Figure 1 This is a schematic diagram of the structure of the large thin-walled cylindrical body of the present invention.
[0016] Figure 2 This is a cross-sectional view of the large thin-walled cylindrical body of the present invention.
[0017] Figure 3 This is an enlarged view of point A of the large thin-walled cylindrical body of the present invention.
[0018] Figure 4 This is a schematic diagram of the special sleeve tooling of the present invention.
[0019] Figure 5 This is a schematic diagram of the special support tooling of the present invention.
[0020] Figure 6 This is a cross-sectional view of the special support tooling of the present invention. Detailed Implementation
[0021] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.
[0022] Example This embodiment provides a method for manufacturing a large thin-walled cylinder, the structure of which is as follows: Figure 1-3 As shown, the axial length of the cylinder is 338mm, the outer diameter of the cylinder is 884mm, and there is a stepped inner hole in the middle of the cylinder. The stepped inner hole consists of a large diameter section 11 and two small diameter sections 12. The two small diameter sections 12 are located on both sides of the large diameter section 11. The diameter of the small diameter section 12 is 864mm, and the diameter of the large diameter section 11 is 866mm. The openings at both ends of the stepped inner hole are chamfered at 45° 13. There are 12 M5 screw holes 14 evenly opened on each of the two end faces of the cylinder.
[0023] The method for manufacturing the above-mentioned large thin-walled cylinder includes the following steps: S1. Cylinder body manufacturing: The plates are cut, rolled, and welded longitudinally to form the cylinder body. The welds on the cylinder body are ground smooth. After the welds pass the inspection, the cylinder body is rounded back and the cylinder body is subjected to solution heat treatment. At this time, the axial length of the cylinder body is 348mm, the outer diameter of the cylinder body is 894mm, and the inner diameter of the cylinder body is 854mm. S2. Rough turning: Using a vertical lathe, turn the right end face of the cylinder body, rough turn the inner hole of the cylinder body, turn the left end face of the cylinder body, and turn the outer circle of the cylinder body in sequence. After natural aging until the residual stress is eliminated, perform a second annealing heat treatment. The operation process is as follows: Place the cylinder body vertically on the worktable of the vertical lathe with the right end face of the cylinder body facing upward. Use a chuck to clamp the outer diameter of the cylinder body, and after correction, turn the right end face of the cylinder body to a roughness of Ra6.3. Then, rough turn the inner hole of the cylinder body to a diameter of 858mm. Then, turn the cylinder body 180° so that the left end face of the cylinder body faces upward. Use a clamp to tighten and fix the inner hole of the cylinder body, turn the left end face of the cylinder body to make the axial length of the cylinder body 340mm, and turn the outer diameter of the cylinder body to a diameter of 890mm. After natural aging for 72 hours, perform a second annealing heat treatment.
[0024] S3, Semi-finish turning: First, use a vertical lathe to finish the right end face of the cylinder, then semi-finish turn the inner hole of the cylinder, and then turn the outer circle of the cylinder to the desired position; The operation process is as follows: After flipping the cylinder body 180°, place it vertically on the worktable of the vertical lathe with the central axis facing upward. Use the chuck to clamp the outer diameter of the cylinder body, correct it, and then finish machine the right end face of the cylinder body to a diameter of 338mm. After flipping the cylinder body 180°, place it vertically on the chuck level block with the central axis facing upward. Use three clamping plates to press the left end face of the cylinder body from the outside and semi-finish machine the inner hole of the cylinder body to a diameter of 862mm. After flipping the cylinder body 180°, place it vertically on the chuck level block with the central axis facing upward. Use three clamping plates to press the right end face of the cylinder body from the inside and machine the outer diameter of the cylinder body to a diameter of 884mm.
[0025] S4. Precision turning: Fix the cylinder body inside the special sleeve fixture, and evenly fill the space between the cylinder body and the special sleeve fixture with yellow sand in the circumferential direction. The pressure plate of the special sleeve fixture is fixed on the chuck of the vertical lathe using a threaded rod. With the right end face of the cylinder body facing up, after correcting the inner hole of the cylinder body, turn the stepped inner hole of the cylinder body into place. Chamfer the right end opening and the left end opening of the stepped inner hole of the cylinder body into place respectively. like Figure 4 As shown, the special sleeve tooling includes a clamping plate 21, a sleeve 22, and a pressure plate 23.
[0026] A stepped hole is opened in the middle of the clamping plate 21. The stepped hole includes an upper hole section 211 and a lower hole section 212. The diameter of the upper hole section 211 is 867mm and the diameter of the lower hole section 212 is 800mm. Six countersunk holes 213 that penetrate the clamping plate 21 are evenly opened along the circumferential direction on the outer side of the stepped hole of the clamping plate 21.
[0027] The sleeve 22 is coaxially fixed to the top surface of the clamping plate 21, and the bottom of the sleeve 22 is welded to the top surface of the clamping plate 21. The inner radius of the sleeve 22 is larger than the outer radius of the cylinder 1, and the difference between the inner radius of the sleeve 22 and the outer radius of the cylinder 1 is at least 4 times the wall thickness of the cylinder. The wall thickness of the sleeve 22 is at least 2 times the wall thickness of the cylinder 1. In this embodiment, the inner diameter of the sleeve 22 is 964 mm, the wall thickness of the sleeve 22 is 20 mm, and the axial length of the sleeve 22 is 333 mm.
[0028] The pressure plate 23 is coaxially placed above the sleeve 22. A through hole 231 is formed in the middle of the pressure plate 23. The diameter of the through hole 231 is larger than the inner diameter of the cylinder 1 but smaller than the outer diameter of the cylinder 1. In this embodiment, the diameter of the through hole 231 is 872 mm. The bottom of the pressure plate 23 has an integrally formed limiting ring protrusion 232. The inner diameter of the limiting ring protrusion 232 matches the outer diameter of the cylinder 1, and the outer diameter of the limiting ring protrusion 232 is smaller than the inner diameter of the sleeve 22. In this embodiment, the outer diameter of the limiting ring protrusion 232 is 904 mm. Besides limiting the top of the cylinder 1, the limiting ring protrusion 232 can also compact the sand near the cylinder. Six connecting holes 233 are evenly formed along the circumference outside the through hole on the pressure plate 23 for the threaded rod 25 to pass through.
[0029] The operation process is as follows: First, use two special support fixtures to support both sides of the inner hole of the cylinder body. Use a micrometer to measure and correct the roundness of the cylinder body. Drill six threaded holes on both sides of the cylinder body and then tap them to form threaded holes corresponding to each countersunk hole 213. After tapping, remove the special support fixtures. Then, place the special sleeve fixture on the worktable of the vertical lathe. After the position is corrected, put the cylinder body into the sleeve 22 and support it from the top surface of the clamping plate 21, with the right end face of the cylinder body facing upward. Use screws 24 to pass through the countersunk hole 213 from the bottom of the clamping plate and thread them into the corresponding threaded holes of the cylinder body to complete the positioning and fixing of the cylinder body. A ring is formed between the cylinder body and the sleeve 22. A circular groove is formed, and yellow sand 26 is poured evenly and slowly into the circular groove along the circumference. The top surface of the yellow sand 26 is flush with the top surface of the sleeve 22. Then, the pressure plate 23 is pressed onto the right end face of the cylinder body. The limiting ring protrusion 232 at the bottom of the pressure plate 23 surrounds the cylinder body. At the same time, the threaded rod 25, which is pre-installed on the worktable of the vertical lathe, passes through the corresponding connecting hole 233 of the pressure plate 23. Nuts 27 are installed on each threaded rod 25 and tightened. The small diameter section diameter of the stepped inner hole of the cylinder body is 864mm and the large diameter section diameter is 866mm. The right end opening and the left end opening of the stepped inner hole of the cylinder body are chamfered at 45° respectively.
[0030] S5. Machining: Remove the cylinder body from the special sleeve tooling, support the two sides of the inner hole of the cylinder body with two special support tools respectively, measure and correct the roundness of the cylinder body with a micrometer, drill the remaining screw holes on both sides of the cylinder body and then tap the threads.
[0031] like Figure 5-6 As shown, the special support fixture includes a circular base plate 31 and eight correction components evenly distributed along the circular base plate. Each correction component includes a hexagonal head screw 34, a nut 33, a washer 32, and a nylon shock-absorbing sleeve 35. The washer 32 is welded and fixed to the top surface of the circular base plate 31, the nut 33 is fixed to the top surface of the washer 32, and the hexagonal head screw 34 is threaded into the nut. The central axes of the eight hexagonal head screws 34 are on the same plane and all intersect perpendicularly with the central axis of the circular base plate 31. The nylon shock-absorbing sleeve 35 is located on the side of the nut 33 away from the central axis of the circular base plate 31. The nylon shock-absorbing sleeve 35 has a threaded groove matching the hexagonal head screw 34, and the end of the hexagonal head screw 34 is threaded into the threaded groove. When installing the special support fixture, place the circular base plate 31 of the special support fixture horizontally on the ground, then put the cylinder body on the outside of the special support fixture, adjust the position of the cylinder body so that the cylinder body is coaxial with the circular base plate 31, and then rotate each internal hexagonal head screw 34 to push the cylinder body through the nylon shock-absorbing sleeve 35, thereby adjusting the roundness of the cylinder body.
[0032] In the above-mentioned manufacturing method, when finishing the stepped inner hole of the cylinder, yellow sand is poured into the outside of the cylinder to support the outer wall of the cylinder. The filling of yellow sand can not only evenly disperse the stress generated during finishing, reduce the local deformation caused by cutting force, and maintain the stability of the cylinder shape, but also increase the overall mass and damping of the tooling, effectively absorb vibration, and make the cutting process more stable, thereby ensuring the machining accuracy of the stepped inner hole of the cylinder.
[0033] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.
Claims
1. A method for manufacturing a large thin-walled cylindrical body, characterized in that: Includes the following steps: S1. Cylinder body manufacturing: The plates are cut, rolled, and welded longitudinally to form the cylinder body. The welds on the cylinder body are ground smooth. After the welds pass the inspection, the cylinder body is rounded and subjected to overall solution heat treatment. S2. Rough turning: Using a vertical lathe, turn the right end face of the cylinder body, rough turn the inner hole of the cylinder body, turn the left end face of the cylinder body, and turn the outer circle of the cylinder body in sequence. After natural aging until the residual stress is eliminated, perform a second annealing heat treatment. S3, Semi-finish turning: First, use a vertical lathe to finish the right end face of the cylinder, then semi-finish turn the inner hole of the cylinder, and then turn the outer circle of the cylinder to the desired position; S4. Precision turning: Fix the cylinder body inside the special sleeve fixture, and evenly fill the space between the cylinder body and the special sleeve fixture with yellow sand in the circumferential direction. The pressure plate of the special sleeve fixture is fixed on the chuck of the vertical lathe using a threaded rod. With the right end face of the cylinder body facing up, after correcting the inner hole of the cylinder body, turn the stepped inner hole of the cylinder body into place. Chamfer the right end opening and the left end opening of the stepped inner hole of the cylinder body into place respectively. S5. Machining: Remove the cylinder body from the special sleeve tooling, support the inner hole of the cylinder body with a special support tooling, measure and correct the roundness of the cylinder body with a micrometer, drill the inner holes of the screw holes on both sides of the cylinder body and then tap the threads.
2. The method for manufacturing a large thin-walled cylinder according to claim 1, characterized in that: The rough turning process of S2 is as follows: Place the cylinder body on the worktable of the vertical lathe with the right end face facing up. Use a chuck to clamp the outer diameter of the cylinder body and correct it. Then turn the right end face of the cylinder body to a roughness of Ra6.
3. Then rough turn the inner hole of the cylinder body, leaving a margin. Then turn the cylinder body 180° so that the left end face of the cylinder body faces up. Use a clamp to tighten and fix the inner hole of the cylinder body. Turn the left end face of the cylinder body, leaving a margin in the axial length of the cylinder body. Turn the outer diameter of the cylinder body, leaving a margin in the outer diameter of the cylinder body. After natural aging for 72 hours, perform a second annealing heat treatment.
3. The method for manufacturing a large thin-walled cylinder according to claim 1, characterized in that: The semi-finish turning process of S3 is as follows: Place the cylinder body on the worktable of the vertical lathe with the right end face facing up. Use a chuck to clamp the outer circle of the cylinder body and correct it. Then, finish machine the right end face of the cylinder body. Rotate the cylinder body 180° and place it on the chuck level block with the left end face facing up. Use a chuck plate to press the left end face of the cylinder body from the outside. Semi-finish turn the inner hole of the cylinder body, leaving a margin in the inner hole. Rotate the cylinder body 180° and place it on the chuck level block with the right end face facing up. Use a chuck plate to press the right end face of the cylinder body from the inside. Turn the outer circle of the cylinder body to the correct position.
4. The method for manufacturing a large thin-walled cylinder according to claim 1, characterized in that: The special sleeve tooling includes a clamping plate, a sleeve, and a pressure plate; A stepped hole is opened in the middle of the clamping plate. The stepped hole includes an upper hole section and a lower hole section. The diameter of the upper hole section is larger than the inner diameter of the cylinder, and the diameter of the lower hole section is smaller than the inner diameter of the cylinder. Several countersunk holes penetrating the clamping plate are evenly opened along the circumferential direction on the outer side of the stepped hole on the clamping plate. The sleeve is coaxially fixed to the top surface of the clamping plate. The inner radius of the sleeve is larger than the outer radius of the cylinder, and the difference between the inner radius of the sleeve and the outer radius of the cylinder is at least 4 times the wall thickness of the cylinder. The wall thickness of the sleeve is at least 2 times the wall thickness of the cylinder. The pressure plate is coaxially placed above the sleeve. A through hole is opened in the middle of the pressure plate. The diameter of the through hole is larger than the inner diameter of the cylinder and smaller than the outer diameter of the cylinder. The bottom of the pressure plate has an integrally formed limiting ring protrusion. The inner diameter of the limiting ring protrusion matches the outer diameter of the cylinder. The outer diameter of the limiting ring protrusion is smaller than the inner diameter of the sleeve. Several connecting holes for the threaded rod to pass through are evenly opened along the circumferential direction on the outside of the through hole on the pressure plate.
5. The method for manufacturing a large thin-walled cylinder according to claim 4, characterized in that: The precision turning operation process of S4 is as follows: First, use a special support fixture to support the inner hole of the cylinder body. Use a micrometer to measure and correct the roundness of the cylinder body. Drill some threaded holes on both sides of the cylinder body and then tap them to form threaded holes that correspond one-to-one with each countersunk hole. After tapping, remove the special support fixture. Then, place the special sleeve fixture on the worktable of the vertical lathe. After the position is corrected, put the cylinder body into the sleeve and support it with the top surface of the clamping plate. With the right end face of the cylinder body facing upward, use screws to pass through the countersunk holes from the bottom of the clamping plate and thread them into the corresponding threaded holes on the cylinder body to complete the positioning and fixing of the cylinder body. A circular groove is formed between the cylinder body and the sleeve. Pour yellow sand evenly and slowly into the circular groove along the circumference until the top surface of the yellow sand is flush with the top surface of the sleeve. Then, press the pressure plate on the right end face of the cylinder body. At the same time, make the threaded rods that were previously installed on the worktable of the vertical lathe pass through the corresponding connecting holes of the pressure plate. Install nuts on each threaded rod and tighten them. The stepped inner hole of the cylinder body is in place. The right and left ends of the stepped inner hole of the cylinder body are chamfered in place.
6. The method for manufacturing a large thin-walled cylinder according to claim 1, characterized in that: The special support fixture includes a circular base plate and several correction components evenly distributed along the circular base plate. The correction assembly includes a hexagon socket head cap screw, a nut, a washer, and a nylon shock-absorbing sleeve. The washer is fixedly connected to the top surface of the circular base plate, the nut is fixed to the top surface of the washer, and the hexagon socket head cap screw is threaded into the nut. The central axes of several hexagon socket head cap screws in the correction assembly are on the same plane and all intersect perpendicularly with the central axis of the circular base plate. The nylon shock-absorbing sleeve is located on the side of the nut away from the central axis of the circular base plate. The nylon shock-absorbing sleeve has a threaded groove that matches the hexagon socket head cap screw, and the end of the hexagon socket head cap screw is threaded into the threaded groove.