Supporting spinning device for gas cylinder for corrosive medium, processing method and gas cylinder

Abstract

This invention relates to the field of gas cylinder manufacturing, providing a supporting spinning device, processing method, and gas cylinder for corrosive media gas cylinders. The supporting spinning device is used to narrow the opening of a thin-walled cylinder to form a shoulder, thus creating the upper half of the gas cylinder. The supporting spinning device includes an outer mold, an inner core mold, and a spinning section. The outer mold is a hollow cylindrical shape with side baffles inside. The inner core mold includes a first cylindrical portion, a hemispherical portion, and a second cylindrical portion. The outer mold is fitted around the outer periphery of the inner core mold, with a gap between them. The thin-walled cylinder extends into the gap, with its bottom ring end abutting against the side baffles. The hemispherical portion and the second cylindrical portion extend out of the opening of the outer mold. When the thin-walled cylinder is spun using the spinning section, the first cylindrical portion and the outer mold provide support for the cylinder body, the side baffles provide support for the bottom ring end, and the hemispherical portion provides support for the shoulder. The supporting spinning device provides support from all parts of the upper half of the cylinder, preventing deformation caused by lack of support in certain areas during spinning, and improving the yield of the gas cylinder.

Description

Technical Field

[0001] This invention relates to the field of gas cylinder manufacturing, and more specifically, to a support and spinning device, processing method, and gas cylinder for corrosive media. Background Technology

[0002] With the rapid development of the global electronics, chemical, pharmaceutical, and aerospace industries, the demand for electronic-grade high-purity and highly corrosive gases (hereinafter referred to as specialty gases) is constantly increasing. Many gases are corrosive, flammable, or toxic, such as HCl, SiH4, H2, and NF3. Once the sealing structure is damaged and leakage occurs, the degree of harm is extremely high. Therefore, the sealing requirements for gas cylinders used to contain specialty gases are very strict. As packaging materials for specialty gases, in addition to internal cleanliness, the sealing structure of the cylinder mouth becomes crucial for the sealing and cleanliness of specialty gas cylinders.

[0003] The demand for seamless aluminum alloy gas cylinders is increasing, as they can be used to store various standard gases, standard gas mixtures, and ultrapure gases to meet the needs of industrial development, especially the electronics industry. The necking process is a crucial step in the production of aluminum alloy gas cylinders. After the cylinder is formed, it should be smoothly necked to the required size to accommodate the necessary valves or stoppers. Lunfer Aluminum Cylinders, the world's largest aluminum cylinder manufacturer, uses a necking process where the open end of the cylinder is heated and then pressed into a mold similar to the neck, achieving a diameter (m=1 / d>0.32). However, this process has drawbacks: increased wrinkles on the inner surface after necking, even overlapping, difficulty in temperature control, and operational challenges, thus requiring high-end equipment and increasing manufacturing costs.

[0004] The CN102000746B seamless gas cylinder forward spinning hot sealing method includes the following steps: (1) heating the steel pipe sealing section to 1050~1100°C; (2) performing 6~7 passes of semi-ellipsoidal forward sealing spinning on the steel pipe sealing section to obtain a semi-ellipsoidal end cap; (3) performing 3~4 passes of bottom thickening spinning on the obtained semi-ellipsoidal end cap; (4) forming spinning of the bottle mouth; (5) finally performing smooth spinning on the surface of the end cap to complete the hot spinning sealing of the seamless gas cylinder. Although it can avoid the waste of unstable products under pressure to a certain extent, the sealing section lacks support, resulting in wrinkles and orange peel on the surface when subjected to compression. Summary of the Invention

[0005] In view of this, the present invention aims to provide a support and spinning device, processing method and cylinder for a gas cylinder for corrosive media, so as to solve the problems of wrinkles and orange peel on the surface of the gas cylinder after the neck is closed in the prior art, which lead to unqualified gas cylinder quality, poor sealing of the cylinder neck and easy failure due to cracking caused by cylinder strain.

[0006] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0007] On one hand, this application proposes a support spinning device for a corrosive medium gas cylinder, used to process a thin-walled cylinder into a shoulder to form the upper half of the gas cylinder. The upper half of the cylinder includes a cylinder body and a shoulder that is smoothly transitioned with an inwardly tapered outer diameter at the cylinder body. The side of the shoulder away from the cylinder body forms the cylinder mouth, and the end of the cylinder body away from the shoulder is the bottom ring end. The support spinning device includes an outer mold, an inner core mold, and a spinning part. The outer mold is a hollow column with a side baffle inside. The inner core mold includes a first cylindrical part, a hemispherical part, and a second cylindrical part in sequence. The outer mold is fitted around the outer periphery of the inner core mold, and there is a gap between the two. The thin-walled cylinder extends into the gap, and the bottom ring end of the cylinder abuts against the side baffle. The hemispherical part and the second cylindrical part extend out of the opening of the outer mold. When spinning a thin-walled cylinder into an upper half bottle using a spinning section, the first cylindrical part is located inside the outer mold throughout the entire processing, providing support for the bottle body along with the outer mold. The side baffle provides support for the bottom ring end of the cylinder, and the hemispherical part provides support for the bottle shoulder. As the bottle shoulder gradually takes shape, the second cylindrical part and the annular hole at the inner end of the bottle mouth fit together and extend out of the bottle mouth. The bottle mouth, as an open area, is easily subjected to inward spinning action. The second cylindrical part, used to support the annular hole, can prevent the bottle mouth from warping or deforming in the radial direction, and the hemispherical part can prevent the bottle mouth and bottle shoulder from warping or deforming in the radial and axial directions. Therefore, the supporting spinning device of this application can provide good support for the upper half bottle from all parts, avoiding deformation caused by lack of support in local areas during spinning, and improving the yield of gas cylinders.

[0008] Furthermore, the spinning section includes a first spinning roller and a second spinning roller. The compression area of ​​the first spinning roller covers a first region of the bottle shoulder away from the bottle mouth, and the compression area of ​​the second spinning roller covers a second region of the bottle shoulder facing the bottle mouth. The projections of the first and second regions onto the cylinder axis cover the projection of the bottle shoulder onto the cylinder axis. This arrangement ensures that, under the combined action of the first and second spinning rollers, the narrowed section of the upper half of the bottle is processed into a bottle shoulder, and that all parts of the bottle shoulder are processed.

[0009] Furthermore, along the direction from the bottle body to the bottle mouth, the outer edge of the first spinning roller sequentially includes an inlet angle, a cylindrical extrusion generatrix, an inflection point, and a section of hemispherical extrusion generatrix. The cylindrical extrusion generatrix is ​​straight, and the degree of curvature of the section of hemispherical extrusion generatrix corresponds to the degree of curvature of the bottle shoulder portion it contacts. The section of hemispherical extrusion generatrix can spin-press the deformed area to process it into a curved bottle shoulder portion, while the cylindrical extrusion generatrix can process the undeformed area into a straight state, preventing the deformed area from bending the undeformed area during spinning, ensuring that a bottle body that meets the requirements and has an inwardly tapered bottle shoulder is obtained.

[0010] Furthermore, the outer edge of the second spinning wheel includes two hemispherical extrusion lines, the curvature of which is adapted to the curvature of the bottle shoulder portion in contact with it.

[0011] On the other hand, this application also proposes a processing method for a gas cylinder for corrosive media, wherein the processing method employs the aforementioned support spinning device, and the processing method includes the following steps:

[0012] Step S1: Narrow the opening of the thin-walled tube to obtain the upper half of the bottle with a shoulder;

[0013] Step S2: Extrude the cake material into a bottom half-bottle;

[0014] Step S3: Seamlessly inertial friction weld the upper half of the bottle and the bottom half of the bottle to obtain the gas cylinder.

[0015] Furthermore, in step S2, the blister pack is extruded into a bottom half-bottle using a reverse extrusion die device. The reverse extrusion die device includes a sleeve, a push rod, and an extrusion rod. The inner wall of the sleeve has the same diameter as the outer diameter of the bottom half-bottle. The push rod and the extrusion rod are capable of servo lifting and lowering movements to extrude the blister pack.

[0016] Furthermore, the head of the top rod has the same shape as the outer side of the bottom half of the bottle, and the bottom of the squeezing rod has the same shape as the inner side of the bottom half of the bottle.

[0017] Furthermore, in step S3, welding is performed using a seamless inertial friction welding device, which includes a stationary fixture, an inertial rotating side fixture, and a flywheel. The inertial rotating side fixture can rotate under the action of a drive mechanism, and the drive mechanism is connected to the flywheel. The stationary fixture can move axially under the action of an axial feed mechanism.

[0018] Furthermore, step S3 is specifically performed as follows:

[0019] S31. Sandblasting, degreasing, and pickling of the inner sides of the upper and bottom half of the bottle;

[0020] S32. The outer wall of the upper half of the bottle is clamped by a stationary clamp, and the outer wall of the bottom half of the bottle is clamped by an inertial rotating side clamp, wherein the inertial rotating side clamp is connected to a flywheel;

[0021] S33. A support rod and an inner plate are provided inside the upper half bottle and the bottom half bottle for support. One end of the support rod extends into the inside of the bottom half bottle and the other end extends into the inside of the upper half bottle and extends out of the bottle mouth. The inner plate is connected to the support rod, and the two ends of the inner plate are respectively fitted with the gaps in the upper half bottle and the bottom half bottle. An outer ring is provided on the outside of the gap. An inner concave ring is provided on the side of the outer ring facing the gap. The inner concave ring is connected to the gap.

[0022] S34. The drive mechanism drives the inertial rotating side clamp and flywheel to rotate. After the flywheel stores enough kinetic energy, the flywheel and drive mechanism are disconnected. Under the action of inertia, the flywheel drives the bottom half bottle to continue to rotate. The axial feed mechanism drives the stationary clamp to feed axially.

[0023] S35. When the flywheel speed drops to the preset value, the axial feeding mechanism applies axial upsetting pressure to the upper half bottle, and the thermoplastic metal at the interface between the upper half bottle and the bottom half bottle is extruded.

[0024] S36. Remove the outer ring, support rod and inner disc to obtain a seamless gas cylinder with the upper half and bottom half welded together.

[0025] On the other hand, this application also proposes a gas cylinder, which is manufactured using the above-mentioned support spinning device or the above-mentioned processing method.

[0026] Compared with the prior art, the support spinning device, processing method, and gas cylinder for corrosive media described in this invention have the following advantages:

[0027] (1) The spinning support device provides good support for all parts of the upper half of the bottle, and there are no wrinkles or orange peel on the inner surface of the bottle shoulder at the bottle neck, ensuring the yield of the gas cylinder and avoiding the failure of the coating due to the strain of the gas cylinder, thereby improving the safety of use.

[0028] (2) The reverse extrusion die device of this application and the method of extruding the cake into a bottom half bottle by using the reverse extrusion die device can simultaneously extrude the inner and outer sides of the bottom half bottle by using the push rod and the extrusion rod to avoid bottom protrusion. Therefore, no additional process is needed to eliminate bottom protrusion, which greatly simplifies the processing process.

[0029] (3) The upper half and the bottom half are made of seamless inertial friction welding. The presence of the concave ring prevents the gas cylinder from producing flash. Therefore, there is no need to perform post-weld processing on the gas cylinder, which solves the problem of difficult processing inside the gas cylinder and ensures that the surface roughness of the internal sandblasting is not damaged. This solves the problem of limited working space inside the gas cylinder and difficulty in sandblasting. Attached Figure Description

[0030] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0031] Figure 1 This is a schematic diagram of the structure of the upper half bottle, the first spinning wheel, and the second spinning wheel of the present invention;

[0032] Figure 2 for Figure 1A magnified view of the area at point I;

[0033] Figure 3 for Figure 2 A sectional view;

[0034] Figure 4 for Figure 3 A magnified view of a portion at point A;

[0035] Figure 5 for Figure 3 A magnified view of the area at point B;

[0036] Figure 6 for Figure 3 A magnified view of point C;

[0037] Figure 7 A schematic diagram of extruding and processing biscuit material using a reverse extrusion die device;

[0038] Figure 8 for Figure 7 A magnified view of the area at point D;

[0039] Figure 9 A schematic diagram of seamless inertial friction welding of the upper half and the bottom half of the bottle;

[0040] Figure 10 for Figure 9 A magnified view of the area at point E;

[0041] Figure 11 This is a schematic diagram of the assembly of the gas cylinder and the gas cylinder valve body.

[0042] Figure 12 for Figure 11 A magnified view of a section at point F.

[0043] Explanation of reference numerals in the attached figures:

[0044] 1. Upper half of the bottle; 102. Bottle body; 103. Annular hole; 104. Bottom ring end of the cylinder; 106. Bottle mouth; 107. Gas cylinder valve body; 108. Valve core; 109. Ring platform; 110. First seal; 111. First threaded pair; 112. Second seal; 113. Second threaded pair; 114. Top cover; 115. Handwheel; 116. Third thread; 117. Lower flange; 118. Elastic corrugated section; 119. Upper flange; 120. Third seal; 2. Bottom half of the bottle; 3. Inertial rotation side clamp; 4. Static 5. Stop clamp; 6. Outer ring; 7. Inner concave ring; 801. Support rod; 9. Inner disc; 10. Outer mold; 11. Inner core mold; 12. First cylindrical part; 13. Hemispherical part; 14. Second cylindrical part; 15. First spinning roller; 16. Second spinning roller; 17. Guide angle; 18. Cylindrical extrusion line; 19. Inflection point; 20. First hemispherical extrusion line; 21. Second hemispherical extrusion line; 32. Sleeve; 43. Push rod; 54. Extrusion rod; 65. Material cake. Detailed Implementation

[0045] The present invention will be further described below with reference to specific embodiments. First, it should be noted that the data in the following experimental examples were obtained by the inventors through numerous experiments. Due to space limitations, only a portion of these data is shown in the specification, and those skilled in the art can understand and implement the present invention based on this data. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the contents of this invention, those skilled in the art can make various modifications or alterations to the invention, and these modifications or alterations also fall within the scope of protection of this application.

[0046] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0047] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0048] like Figures 1-6 As shown, a supporting spinning device for a corrosive medium gas cylinder according to the present invention is used to process a thin-walled cylinder into a shoulder to form the upper half 1 of the gas cylinder. Typically, the thin-walled cylinder is a cylindrical tube, which facilitates its processing into the shape of a gas cylinder. The side of the gas cylinder near the mouth 106 is the upper half 1, which includes a body 102 and a shoulder that tapers inward at the body 102 and transitions smoothly. The side of the shoulder away from the body 102 forms the mouth 106, and the end of the body 102 away from the shoulder is the bottom ring end 104.

[0049] The supporting spinning device includes an outer mold 801, an inner core mold 802, and a spinning part. The outer mold 801 is a hollow column with a side baffle inside. The inner core mold 802 includes a first cylindrical part 8021, a hemispherical part 8022, and a second cylindrical part 8023 in sequence. The outer mold 801 is sleeved on the outer periphery of the inner core mold 802, and there is a gap between the two. The thin-walled cylinder extends into the gap, and the bottom ring end 104 of the cylinder abuts against the side baffle. The hemispherical part 8022 and the second cylindrical part 8023 extend out of the opening of the outer mold 801.

[0050] It should be noted that, considering the need to process the thin-walled cylinder while it is rotating, the gap between the outer mold 801 and the inner core mold 802 should not be too large. The inner core mold 802 and the thin-walled cylinder can be connected by thermal expansion and contraction or other means, so that when the inner core mold 802 rotates, the thin-walled cylinder can also rotate, and the rotation is along the axis of the thin-walled cylinder.

[0051] When the thin-walled cylinder is spun and processed into the upper half of the bottle 1 using a spinning section, the first cylindrical portion 8021 is located inside the outer mold 801 throughout the entire processing. Together with the outer mold 801, they provide support for the bottle body 102. The side baffle provides support for the bottom ring end 104, and the hemispherical portion 8022 provides support for the bottle shoulder. As the bottle shoulder gradually takes shape, the second cylindrical portion 8023 and the annular hole 103 at the inner end of the bottle mouth 106 come into contact and extend out of the bottle mouth 106. The bottle mouth 106, being an open area, is easily subjected to inward spinning action. The second cylindrical portion 8023 supports the annular hole 103, preventing the bottle mouth 106 from warping or deforming in the radial direction. The hemispherical portion 8022 prevents the bottle mouth 106 and the bottle shoulder from warping or deforming in both the radial and axial directions. Therefore, the support spinning device of this application can provide good support for the upper half of the bottle 1 from all parts, avoiding deformation caused by lack of support in local areas during spinning, and improving the yield of the gas cylinder. In particular, the bottle shoulder at the neck can reduce instability and wrinkles during spinning, avoiding excessive defective products and poor sealing of the bottle mouth 106 due to processing quality problems.

[0052] Considering that gas cylinders are typically cylindrical, to better match the upper half of cylinder 1, the outer mold 801, inner core mold 802, and second cylindrical portion 8023 are all cylindrical. The hemispherical portion 8022 is hemispherical and matches the cylinder shoulder, providing all-around support for the cylinder shoulder. The second cylindrical portion 8023 matches the cylinder mouth 106, also providing support at the cylinder mouth 106. Furthermore, the thin-walled cylinder is made of rust-resistant aluminum alloy LF3. After processing into a gas cylinder, the inner diameter Φ of the cylinder body 102 is 200mm, and the wall thickness t is 3mm; the inner diameter S of the cylinder shoulder is 100mm, and the wall thickness t is 3mm.

[0053] As a preferred example of this application, the inner core mold 802 can heat the thin-walled cylinder to the spinning temperature to facilitate the processing of the bottle shoulder. The spinning temperature is 400~480℃. The inner core mold 802 is axially movable. The outer mold 801 can servo-push the bottom ring end 104 of the cylinder for axial servo feed.

[0054] The spinning section includes a first spinning roller 803 and a second spinning roller 804. The squeezing area of ​​the first spinning roller 803 covers a first region of the bottle shoulder away from the bottle mouth 106, and the squeezing area of ​​the second spinning roller 804 covers a second region of the bottle shoulder facing the bottle mouth 106. The projections of the first and second regions onto the cylinder axis can cover the projection of the bottle shoulder onto the cylinder axis. In this application, the first spinning roller 803 and the second spinning roller 804 do not work sequentially, but work simultaneously to process different regions of the upper half of the bottle 1.

[0055] This configuration ensures that the upper half of the bottle 1, from its neck to its shoulder, is machined under the combined action of the first spinning roller 803 and the second spinning roller 804, and that all areas of the shoulder are machined. Existing technologies typically use only one spinning roller. To ensure a shoulder meets precision requirements, the design and dimensional accuracy of the spinning roller are critical, and a single spinning roller usually requires significant space to machine all areas of the shoulder. This application utilizes two spinning rollers, with the rotation center of the spinning rollers equidistant from the center of the bottle shoulder. Compared to the single spinning roller in existing technologies, this optimizes the volume of the spinning rollers by approximately 25%, saving on the workload of multi-axis CNC machining. Simultaneously, it optimizes the surface machining workload by approximately 30%, saving on the workload of multi-axis CNC machining of curved surfaces.

[0056] The projection of the first and second regions on the cylinder axis as described here can cover the projection of the cylinder shoulder on the cylinder axis means that the projections of the first and second regions on the cylinder axis overlap, or the projections of the first and second regions just touch, ensuring that they can cover the projection of the cylinder shoulder on the cylinder axis, so that the spinning part can be processed to all parts of the cylinder shoulder.

[0057] The first spinning wheel 803 and the second spinning wheel 804 each have two degrees of freedom, namely, they can move left and right and rotate along their own axis.

[0058] As a preferred example of this application, the outer mold 801 and the inner core mold 802 are respectively driven by motors, causing the thin-walled cylinder to move towards the two spinning rollers. The inner core mold 802 rotates under the drive of the motor, causing the thin-walled cylinder to rotate synchronously and coaxially. The outer mold 801 can perform axial servo feed operation under the drive of the motor. The first spinning roller 803 and the second spinning roller 804 do not require motor drive. When the thin-walled cylinder moves to contact the two spinning rollers under the action of the inner and outer molds, the rotation of the thin-walled cylinder will drive the two spinning rollers to move, thereby utilizing the two spinning rollers to perform corresponding processing on the thin-walled cylinder. This design saves motors and is beneficial for resource conservation.

[0059] like Figure 4 As shown, the outer edge of the first spinning roller 803, along the direction from the bottle body 102 to the bottle mouth 106, sequentially includes an inlet angle 805, a cylindrical extrusion generatrix 806, an inflection point 807, and a section of hemispherical extrusion generatrix 808. The cylindrical extrusion generatrix 806 is straight, and the degree of curvature of the section of hemispherical extrusion generatrix 808 is adapted to the bottle shoulder portion it contacts. That is, the straight cylindrical extrusion generatrix 806 bends at the inflection point 807 to form an arc-shaped section of hemispherical extrusion generatrix 808. The cylindrical extrusion generatrix 806 and the section of hemispherical extrusion generatrix 808 respectively cover the undeformed area and the deformed area of ​​the bottle shoulder. The undeformed area is close to the bottle body 102 and is the critical point between the bottle body 102 and the bottle shoulder. When the first spinning wheel 803 spins the thin-walled cylinder, the hemispherical extrusion line 808 spins the deformed area, shaping it into a curved bottle shoulder. The cylindrical extrusion line 806 straightens the undeformed area, preventing the deformed area from bending the undeformed area during spinning. This ensures that the desired shape is achieved, with the bottle body 102 being straight and the bottle shoulder having an inwardly tapered upper half. The guide angle 805 acts as a guide, allowing the thin-walled cylinder to feed smoothly.

[0060] like Figure 6 As shown, the outer edge of the second spinning roller 804 includes two hemispherical extrusion lines 809, the curvature of which is adapted to the curvature of the bottle shoulder portion in contact with it.

[0061] Correspondingly, the extrusion areas of the first hemispherical extrusion busbar 808 and the second hemispherical extrusion busbar 809 overlap, or their extrusion areas are adjacent, thereby better processing the upper half of the bottle 1 into a bottle shoulder, and ensuring that all parts of the bottle shoulder can be processed. Preferably, the extrusion areas of the first hemispherical extrusion busbar 808 and the second hemispherical extrusion busbar 809 overlap to avoid gaps between their extrusion areas, which could result in some areas of the necking section not being spun.

[0062] Since the first spinning roller 803 has a cylindrical extrusion generatrix 806, it needs to spin the undeformed area. Therefore, the rotation axis of the first spinning roller 803 is parallel to the axis of the bottle body 102, while the rotation axis of the second spinning roller 804 is not parallel to the axis of the bottle body 102.

[0063] The processing method of the corrosive medium gas cylinder of the present invention includes the following steps:

[0064] Step S1: Narrow the opening of the thin-walled tube to obtain the upper half of the bottle 1 with a shoulder;

[0065] Step S2: Extrude the cake 10 into a bottom half-bottle 2;

[0066] Step S3: Seamlessly inertial friction weld the upper half bottle 1 and the bottom half bottle 2 to obtain the gas cylinder.

[0067] In step S1, the bottle shoulder is processed using a support spinning device.

[0068] The specific operation of step S1 is as follows:

[0069] S11. Insert the thin-walled cylinder into the gap between the outer mold 801 and the inner core mold 802 until the bottom ring end 104 of the cylinder abuts against the side baffle of the outer mold 801, and ensure that the end of the thin-walled cylinder away from the bottom ring end 104 extends out of the opening of the outer mold 801, but does not exceed the second cylindrical part 8023 of the inner core mold 802.

[0070] S12. The thin-walled cylinder and the inner core mold 802 rotate synchronously and coaxially. Adjust the rotation speed of the thin-walled cylinder and heat the constriction section of the thin-walled cylinder to 400~480℃.

[0071] S13. Determine the shape of the first spinning wheel 803 and the second spinning wheel 804, bring their working surfaces close to the outer wall of the closing section, and perform multiple passes of hemispherical positive closing spinning.

[0072] In step S12, the rotational speed of the thin-walled cylinder determines the thickness and length of the bottle shoulder. The rotational speed of the thin-walled cylinder is determined according to the shoulder size requirements of different gas cylinders. As a specific example of this application, the rotational speed of the thin-walled cylinder is 400~600 rpm.

[0073] In step S13, the number of passes for processing the necking section of the thin-walled cylinder is determined based on the shoulder size requirements of different gas cylinders and the operator's experience. As a specific example of this application, the necking section is subjected to 10 to 20 passes of hemispherical forward necking spinning. Since the spinning operation using a spinning section is prior art, it will not be described in detail here.

[0074] In step S2, as Figures 7-8As shown, a reverse extrusion die device is used to extrude the cake 10 into a bottom half-bottle 2. The reverse extrusion die device includes a sleeve 901, a push rod 902, and an extrusion rod 903. The inner wall of the sleeve 901 has the same diameter as the outer diameter of the bottom half-bottle 2. The push rod 902 and the extrusion rod 903 are capable of servo lifting and lowering movements to extrude the cake 10. The head of the push rod 902 has the same shape as the outer side of the bottom half-bottle 2, and the bottom of the extrusion rod 903 has the same shape as the inner side of the bottom half-bottle 2.

[0075] As a preferred example of this application, the head of the top rod 902 protrudes in the direction of its head, and the bottom of the squeezing rod 903 is recessed in the direction away from its bottom. The protrusion of the top rod 902 and the recess of the squeezing rod 903 better adapt to the shape of the bottom half-bottle 2 inside and out.

[0076] The specific operation of step S2 is as follows:

[0077] The cake 10 is placed into the sleeve 901, the push rod 902 is pushed to move upward in the sleeve 901, and the extrusion rod 903 is pushed to move downward in the sleeve 901. The push rod 902 and the extrusion rod 903 work together to extrude the cake 10 into a bottom half bottle 2.

[0078] The material of the gas cylinder 10 is selected based on the characteristics of the gas cylinder itself. Typically, the material used for the gas cylinder 10 is the same as that used for the thin-walled cylinder, and rust-resistant aluminum alloy LF3 can be selected for both. A step-by-step extrusion method can be used during the extrusion process to ensure that the gas cylinder 10 has a uniform wall thickness and high forming accuracy after extrusion.

[0079] In industrial production, many cups require extrusion die processing. Currently, seamless aluminum alloy gas cylinders commonly employ a reverse extrusion and deep drawing process. Cups processed using conventional reverse extrusion dies exhibit a bulge at the center of the bottom during deep drawing, with the bulge exceeding the original base surface by 5-8 mm, severely affecting the cup's upright position. To eliminate this bulge, a bottom pressing method is typically used, flattening the protruding center on a hydraulic press, followed by direct machining. However, because the machining position is far from the clamping point, tool vibration is prone to occur, affecting processing speed and compromising accuracy. This current processing method also adds an extra processing step, inevitably increasing equipment and human resource requirements and manufacturing costs.

[0080] By using the reverse extrusion die device of this application and the method of extruding the cake 10 into the bottom half bottle 2 using the reverse extrusion die device, the inner and outer sides of the bottom half bottle 2 are simultaneously extruded by the push rod 902 and the extrusion rod 903, avoiding bottom protrusion. Therefore, there is no need to add an extra process to eliminate the bottom protrusion, which greatly simplifies the processing process.

[0081] In step S3, as Figures 9-10As shown, welding is performed using a seamless inertial friction welding device, which includes a stationary fixture 4, an inertial rotating side fixture 3, and a flywheel. The inertial rotating side fixture 3 can rotate under the action of a drive mechanism, and the drive mechanism is connected to the flywheel (not shown in the figure). The flywheel is used to store the huge rotational kinetic energy required for welding. The stationary fixture 4 can move axially under the action of an axial feed mechanism.

[0082] The specific operation of step S3 is as follows:

[0083] S31. The inner sides of the upper half bottle 1 and the bottom half bottle 2 are sandblasted, degreased, and pickled.

[0084] S32. The outer wall of the upper half bottle 1 is clamped by the stationary clamp 4, and the outer wall of the bottom half bottle 2 is clamped by the inertial rotating side clamp 3, wherein the inertial rotating side clamp 3 is connected to the flywheel;

[0085] S33. A support rod 6 and an inner plate 7 are provided inside the upper half bottle 1 and the bottom half bottle 2 for support. One end of the support rod 6 extends into the interior of the bottom half bottle 2, and the other end extends into the interior of the upper half bottle 1 and extends out of the bottle mouth 106. The inner plate 7 is connected to the support rod 6, and the two ends of the inner plate 7 are respectively fitted with the gaps in the upper half bottle 1 and the bottom half bottle 2. An outer ring 5 is provided on the outside of the gap. An inner concave ring 501 is provided on the side of the outer ring 5 facing the gap. The inner concave ring 501 is connected to the gap.

[0086] S34. The drive mechanism drives the inertial rotating side clamp 3 and the flywheel to rotate. After the flywheel stores enough kinetic energy, the flywheel and the drive mechanism are disconnected. Under the action of inertia, the flywheel drives the bottom half bottle 2 to continue to rotate. The axial feed mechanism drives the stationary clamp 4 to feed axially.

[0087] S35. When the flywheel speed drops to the preset value, the axial feeding mechanism applies axial forging pressure to the upper half bottle 1, and the thermoplastic metal at the interface between the upper half bottle 1 and the bottom half bottle 2 is extruded.

[0088] S36. Remove the outer ring 5, support rod 6 and inner disc 7 to obtain a seamless gas cylinder with the upper half bottle 1 and the bottom half bottle 2 welded together.

[0089] In step S31, the inner sides of the upper half bottle 1 and the bottom half bottle 2 are sandblasted with a mesh size of 800-900.

[0090] In step S33, before the upper half bottle 1 and the bottom half bottle 2 are connected, there is a gap when they are pre-assembled together. The inner plate 7 is located inside the two, and both ends of the inner plate 7 are located at the gap. That is, the inner plate 7 is set inside the gap, and the outer ring 5 is set outside the gap.

[0091] In step S34, frictional resistance is generated after the upper half of the bottle 1 and the bottom half of the bottle 2 come into contact, causing the flywheel speed to gradually decrease. The resulting frictional heat raises the contact surface between the upper half of the bottle 1 and the bottom half of the bottle 2 to a plastic state, and the kinetic energy of the flywheel is continuously converted into thermal energy. Using inertial friction welding, the core temperature can reach 400~490℃.

[0092] In step S35, due to the presence of the concave ring 501, the thermoplastic metal material can flow into the concave ring 501 at high temperature without entering the inside of the gas cylinder. Simultaneously, due to the obstruction of the inner disc 7, it will not affect the interior of the gas cylinder. That is, the extruded thermoplastic metal will not produce flash on the inside of the gas cylinder, only on the outside, where flash of a controllable shape will be produced. The flash on the outside of the gas cylinder can be removed simply by grinding, while the inner surface retains the sandblasting effect.

[0093] As a preferred example of this application, the inner disc 7 and the outer ring 5 are made of quartz. The main component of quartz is high-purity silicon dioxide, which has a maximum temperature resistance of 1650℃. This not only prevents damage from high temperatures during inertial friction welding but also provides resistance to vibration and breakage. After welding, the disc is broken and poured out. Further, the inner disc 7 and the outer ring 5 are broken by contact with an ultrasonic steel rod. Since the inner disc 7 is connected to the support rod 6, the support rod 6 can be easily removed after the inner disc 7 is broken and poured out.

[0094] After welding, an electroplated Teflon liner is applied to the inner wall of the bottle. As a specific example of this application, a composite intermediate coating of nickel-iron and PTFE particles is electroplated to improve the adhesion of the Teflon, with a thickness of 20±7 μm. The Teflon is then cured by ultrasonic electrostatic spraying of a PTFE dispersion, followed by low-temperature drying to evaporate the base solution, and high-temperature sintering. The low-temperature drying conditions are: temperature 80±5℃, time 25~35 min. The high-temperature sintering conditions are: temperature 370±5℃, time 13~14 min.

[0095] This application also proposes a seamless gas cylinder, which is prepared using the above-described processing method. A spinning support device provides good support for all parts of the upper half of the cylinder 1, eliminating wrinkles and orange peel texture on the inner surface of the cylinder shoulder at the cylinder neck, ensuring a high yield rate, and preventing plating failure due to cylinder strain, thereby improving safety. The upper half of the cylinder 1 and the bottom half of the cylinder 2 are seamlessly inertial friction welded. The presence of the concave ring 501 prevents flash from forming inside the cylinder, eliminating the need for post-weld processing of the cylinder interior. This solves the problem of difficult internal cylinder processing, ensures that the surface roughness of the internal sandblasting is not damaged, and thus solves the problem of limited working space and difficulty in sandblasting inside the cylinder.

[0096] like Figures 10-11As shown, the cylinder opening 106 is connected to the cylinder valve body 107 via a first threaded pair 111. The cylinder opening 106 and the cylinder valve body 107 are sealed by a first sealing element 110 to prevent corrosive media from corroding the threads of the first threaded pair 111.

[0097] The gas cylinder valve body 107 has a receiving space, and the receiving space is provided with a gas outlet. The gas outlet has a second threaded pair 113, and a second sealing element 112 is provided on the outside of the gas outlet to prevent corrosive media from corroding the threads of the second threaded pair 113.

[0098] As a preferred example of this application, a dovetail groove is provided on the outside of the air outlet, and the second seal 112 is disposed in the dovetail groove to prevent the second seal 112 from falling off.

[0099] The upper end of the gas cylinder valve body 107 is connected to the bellows upper flange 119. The gas cylinder valve body 107 and the bellows upper flange 119 are sealed by a third sealing element 120 to prevent corrosive media from corroding the thread pair of the adjusting third thread 116.

[0100] The first seal 110, the second seal 112, and the third seal 120 are elastic seals. As a specific example of this application, the first seal 110, the second seal 112, and the third seal 120 are made of polytetrafluoroethylene (PTFE).

[0101] The bellows includes an upper flange 119, an elastic corrugated section 118, and a lower flange 117. The upper flange 119 is in the shape of a circular hole, and the lower flange 117 is a disc with a blind hole in the middle. The bellows is disposed inside the receiving space.

[0102] The gas cylinder valve body 107 and the bellows are connected by a valve core 108. The gas cylinder valve body 107 has a mounting hole facing the cylinder opening 106, and the mounting hole gradually decreases in size from the cylinder opening 106. One end of the valve core 108 is cylindrical, and the other end is a frustum-shaped annular 109. The cylindrical end is press-fitted into the blind hole of the lower flange 117, and the frustum-shaped annular 109 and the mounting hole form a frustum seal. This frustum seal, as a type of surface seal, improves the sealing effect and reduces leakage.

[0103] When there is no pressure difference between the inside and outside of the gas cylinder, the elastic corrugated section 118 of the bellows is in a relaxed state, so that the valve core 108 and the gas cylinder valve body 107 form a frustum seal. When the bellows is subjected to external force, causing the elastic corrugated section 118 to be in a compressed state, it presses against the valve core 108 and moves it toward the cylinder opening 106, so that the valve core 108 extends out of the mounting hole to realize the function of venting to the outside.

[0104] As a preferred example of this application, the side of the gas cylinder valve body 107 away from the bellows is connected to the top cover 114, the top cover 114 and the handwheel 115 are connected by a third thread 116, and the bottom of the handwheel 115 passes through the top cover 114 and abuts against the cylindrical end of the valve core 108.

[0105] The elastic state of the elastic corrugated section 118 is changed by turning the handwheel 115. Different degrees of turning of the handwheel 115 result in different degrees of compression of the elastic corrugated section 118, and different lengths of the valve core 108 extending out of the mounting hole. This application can achieve flow control of corrosive media by turning the handwheel 115.

[0106] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A support spinning device for a corrosive medium gas cylinder, used to process a thin-walled cylinder into a shoulder to form the upper half (1) of the gas cylinder, the upper half (1) comprising a cylinder body (102) and a shoulder with a smooth transition and an inwardly tapered outer diameter at the cylinder body (102), the side of the shoulder facing away from the cylinder body (102) forming a cylinder mouth (106), and the end of the cylinder body (102) facing away from the shoulder being a cylinder bottom ring end (104), characterized in that, The supporting spinning device includes an outer mold (801), an inner core mold (802), and a spinning part. The outer mold (801) is a hollow column with a side baffle inside. The inner core mold (802) includes a first cylindrical part (8021), a hemispherical part (8022), and a second cylindrical part (8023) in sequence. The outer mold (801) is fitted around the outer periphery of the inner core mold (802), and there is a gap between the two. The thin-walled cylinder extends into the gap, and the bottom ring end (104) of the cylinder abuts against the side baffle. The hemispherical part (8022) and the second cylindrical part (8023) extend out of the opening of the outer mold (801).

2. The supporting spinning device according to claim 1, characterized in that, The spinning section includes a first spinning wheel (803) and a second spinning wheel (804). The squeezing area of ​​the first spinning wheel (803) covers a first area of ​​the bottle shoulder away from the bottle mouth (106), and the squeezing area of ​​the second spinning wheel (804) covers a second area of ​​the bottle shoulder facing the bottle mouth (106). The projections of the first area and the second area on the cylinder axis can cover the projection of the bottle shoulder on the cylinder axis.

3. The supporting spinning device according to claim 2, characterized in that, The outer edge of the first spinning roller (803) along the direction from the bottle body (102) to the bottle mouth (106) includes, in sequence, an inlet angle (805), a cylindrical extrusion generatrix (806), an inflection point (807), and a section of hemispherical extrusion generatrix (808). The cylindrical extrusion generatrix (806) is straight, and the curvature of the section of hemispherical extrusion generatrix (808) and the bottle shoulder portion in contact with it is adapted to each other.

4. The supporting spinning device according to claim 2, characterized in that, The outer edge of the second spinning roller (804) includes two hemispherical extrusion lines (809), the curvature of which is adapted to the curvature of the bottle shoulder portion in contact with it.

5. A method for processing a gas cylinder for corrosive media, characterized in that, The processing method employs the support spinning device according to any one of claims 1 to 4, and the processing method includes the following steps: Step S1: Close the opening of the thin-walled tube to obtain the upper half of the bottle with a shoulder (1). Step S2: Extrude the cake (10) into a bottom half bottle (2); Step S3: Seamlessly inertial friction weld the upper half bottle (1) and the bottom half bottle (2) to obtain the gas cylinder.

6. The processing method according to claim 5, characterized in that, In step S2, the cake (10) is extruded into a bottom half bottle (2) using a reverse extrusion die device. The reverse extrusion die device includes a sleeve (901), a push rod (902), and an extrusion rod (903). The inner wall of the sleeve (901) has the same outer diameter as the bottom half bottle (2). The push rod (902) and the extrusion rod (903) are capable of servo lifting and lowering movements to extrude the cake (10).

7. The processing method according to claim 6, characterized in that, The top of the top rod (902) has the same shape as the outer side of the bottom half-bottle (2), and the bottom of the squeezing rod (903) has the same shape as the inner side of the bottom half-bottle (2).

8. The processing method according to claim 5, characterized in that, In step S3, welding is performed using a seamless inertial friction welding device, which includes a stationary fixture (4), an inertial rotation side fixture (3), and a flywheel. The inertial rotation side fixture (3) can rotate under the action of a drive mechanism, and the drive mechanism is connected to the flywheel. The stationary fixture (4) can move axially under the action of an axial feed mechanism.

9. The processing method according to claim 5, characterized in that, The specific operation of step S3 is as follows: S31. The inner sides of the upper half bottle (1) and the bottom half bottle (2) are sandblasted, degreased, and pickled; S32. The outer wall of the upper half bottle (1) is clamped by a stationary clamp (4), and the outer wall of the bottom half bottle (2) is clamped by an inertial rotating side clamp (3), wherein the inertial rotating side clamp (3) is connected to a flywheel; S33. A support rod (6) and an inner plate (7) are provided inside the upper half bottle (1) and the bottom half bottle (2) for support. One end of the support rod (6) extends into the interior of the bottom half bottle (2), and the other end extends into the interior of the upper half bottle (1) and extends out of the bottle mouth (106). The inner plate (7) is connected to the support rod (6), and the two ends of the inner plate (7) are respectively fitted with the gaps in the upper half bottle (1) and the bottom half bottle (2). An outer ring (5) is provided on the outside of the gap. The outer ring (5) has an inner concave ring (501) on the side facing the gap. The inner concave ring (501) is connected to the gap. S34. The drive mechanism drives the inertial rotating side clamp (3) and the flywheel to rotate. After the flywheel stores enough kinetic energy, the flywheel and the drive mechanism are disconnected. Under the action of inertia, the flywheel drives the bottom half bottle (2) to continue to rotate. The axial feed mechanism drives the stationary clamp (4) to feed axially. S35. When the flywheel speed drops to the preset value, the axial feeding mechanism applies axial upsetting pressure to the upper half bottle (1), and the thermoplastic metal at the interface between the upper half bottle (1) and the bottom half bottle (2) is extruded. S36. Remove the outer ring (5), support rod (6) and inner disc (7) to obtain a seamless gas cylinder with the upper half (1) and the bottom half (2) welded together.

10. A gas cylinder, characterized in that, The gas cylinder is manufactured using the support spinning device described in any one of claims 1 to 4, or using the processing method described in any one of claims 5 to 9.

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