A large-capacity thin-wall steel liner closing forming method

Abstract

The application discloses a large-volume thin-wall steel inner container closing forming method, and solves the technical problems of low qualified rate and high manufacturing cost of the existing large-volume thin-wall steel inner container closing forming. The 30CrMo steel plate is subjected to multiple deep drawing and annealing processes to form a thin-wall cup-shaped body with a wall thickness of 3.5 mm, and the thin-wall cup-shaped body is subjected to closing forming through hot spinning after length alignment and mouth alignment. The application has the advantages of simple structure, scientific and reasonable design, and convenient use. The 30CrMo steel plate is subjected to multiple deep drawing and annealing processes to form a thin-wall cup-shaped body with a wall thickness of 3.5 mm, and the thin-wall cup-shaped body is subjected to closing forming through hot spinning after length alignment and mouth alignment. The whole spinning closing forming process realizes the closing forming of the large-volume thin-wall steel inner container through temperature control and spinning pass optimization.

Description

Technical Field

[0001] This invention belongs to the field of pressure vessel manufacturing technology, specifically relating to a method for forming a large-volume thin-walled steel inner liner. Background Technology

[0002] Natural gas is a clean and efficient energy source with advantages such as being environmentally friendly, economical, and safe. Using natural gas as vehicle fuel offers advantages such as high calorific value, low exhaust pollution, reliable supply, and low price, making it a global trend in clean fuel development for vehicles. Gas cylinders, as storage containers for natural gas, need to be pressure-resistant, well-sealed, and lightweight.

[0003] Therefore, to meet the above requirements for natural gas storage cylinders, the inner liner of natural gas storage cylinders is generally made of steel. There are typically two processing methods for the steel inner liner of natural gas storage cylinders. One method is tubular forming, where the main pipe is cut to a certain length, and a single- or double-ended inner liner is formed by tapering the bottom and opening. The cylinder is then formed by winding fibers. This type of steel inner liner cylinder has a thicker wall, requires more steel tubing during manufacturing, and results in a heavier overall cylinder weight. Furthermore, the single-ended inner liner with tapered bottoms carries the risk of bottom leakage, which reduces product quality. The other processing method is deep drawing of steel plates to prepare the steel inner liner. Steel plates are cut into round plates and formed into a cup shape through multiple deep drawing processes or strong spinning processes. This method produces a high-quality cup shape without the risk of bottom leakage. By controlling the thinning during deep drawing, the wall thickness of the steel inner liner cylinder can be significantly reduced, decreasing the amount of steel used and the overall weight of the cylinder. However, the traditional deep drawing method for preparing steel inner liners has drawbacks such as high manufacturing costs and small cylinder volume.

[0004] Therefore, a method for forming a large-volume thin-walled steel inner liner is designed to solve the technical problems of low inner liner qualification rate and high manufacturing cost in the existing large-volume thin-walled steel inner liner forming process. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for forming a large-volume thin-walled steel inner liner, thereby solving the technical problems of low inner liner qualification rate and high manufacturing cost in the existing large-volume thin-walled steel inner liner forming process.

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

[0007] A method for forming a large-volume thin-walled steel inner liner involves using 30CrMo steel plate to form a thin-walled cup-shaped body with a wall thickness of 3.5mm after multiple deep drawing and annealing processes. The thin-walled cup-shaped body is then formed by hot spinning after being aligned to a fixed length.

[0008] Furthermore, it includes the following steps:

[0009] Step 1: The 30CrMo steel plate is drawn into a rough billet through multiple deep drawing processes;

[0010] Step 2: After the rough blank is cut with a saw, it is formed into a thin cup shape;

[0011] Step 3: Place the thin cup-shaped body into an induction furnace for heating;

[0012] Step 4: After heating is complete, transfer the thin cup-shaped body into a spinning machine for spinning and shaping.

[0013] Furthermore, the wall thickness of the thin cup-shaped body is 3.5 mm.

[0014] Furthermore, in step 3, when the thin cup-shaped body is heated by an induction furnace, the opening of the thin cup-shaped body is inserted into the induction furnace for heating, with an insertion length of 500 mm.

[0015] Preferably, the heating temperature is 1140-1180℃;

[0016] Preferably, the rotational speed of the thin cup-shaped body in the medium-frequency furnace is 6 rad / min.

[0017] Furthermore, in step 4, when the thin cup-shaped body is transferred into the spinning machine, after the temperature of the thin cup-shaped body in the medium-frequency furnace reaches the set temperature, the heating is stopped, and then a robotic arm is used to clamp and transfer the thin cup-shaped body and clamp it on the spinning machine.

[0018] Furthermore, in step 4, before the thin cup-shaped body is spun and shaped in the spinning machine, the thin cup-shaped body is first gripped by the spinning machine's jaws, and three heat guns are fixed on the spinning machine's rotating wheel and ignited to heat the thin cup-shaped body. Then, the spinning machine's rotating wheel is pressed down to begin sizing the thin cup-shaped body.

[0019] Furthermore, during the process of closing the thin cup-shaped body, in addition to using three heat guns fixed on the spinning machine wheel to heat the thin cup-shaped body throughout the process, it is also necessary to manually hold one heat gun for manual heating, and remove the manual heating when the bottle is exiting the nozzle.

[0020] Furthermore, in step 4, when spinning and sealing the thin cup-shaped body, 15 necking processes, 15 thickening processes, 4 nozzle-extrusion processes, and 1 shaping process are required to complete the sealing process.

[0021] Furthermore, in step 4, during the spinning and sealing process of the thin cup-shaped body, multiple small spinning passes, material quantity, and stable heat replenishment measures are adopted to reduce the risk of edge turning and wrinkling during the spinning process of the thin cup-shaped body.

[0022] Furthermore, the spinning machine includes a spinning machine base, a main shaft mounted on the spinning machine base and connected to a rotary drive device, a chuck mounted on the main shaft for gripping the thin cup-shaped body fitted on the main shaft so that the thin cup-shaped body rotates synchronously with the main shaft, a slide rail mounted on the spinning machine base, a spinning carriage slidably mounted on the slide rail, a spinning wheel shaft rotatably mounted on the spinning carriage and connected to the rotary drive device, and a spinning wheel mounted on the spinning wheel shaft for cooperating with the main shaft to spin the thin cup-shaped body; three heat guns A are mounted side by side on the spinning wheel, and a heat gun B for manual heat replenishment is also placed next to the spinning machine base.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] This invention features a simple structure, a scientifically sound design, and ease of use. It utilizes 30CrMo steel plate, which undergoes multiple deep drawing and annealing processes to create a thin-walled cup-shaped body with a wall thickness of 3.5mm. After the cup-shaped body is cut to a fixed length and aligned at the rim, it is then shaped by hot spinning. The entire spinning and sizing process is optimized through temperature control and spinning passes to achieve the sizing of a large-volume thin-walled steel inner liner. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the process for forming the large-volume thin-walled steel inner liner according to the present invention.

[0026] Figure 2 This is a diagram showing the state of the 30CrMo steel plate of the present invention after being deep drawn into a thin-walled cup shape.

[0027] Figure 3 This is a diagram showing the heating state of the thin-walled cup-shaped body of the present invention inside an intermediate frequency furnace.

[0028] Figure 4 This is a schematic diagram of the spinning machine structure of the present invention.

[0029] The names corresponding to the reference numerals in the attached figures are as follows:

[0030] 1-Spinning machine base, 2-Main shaft, 3-Claw, 4-Thin cup-shaped body, 5-Slide rail, 6-Spinning carriage, 7-Spinning wheel shaft, 8-Spinning wheel, 9-Heating gun A, 10-Heating gun B. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0032] Example 1, as Figure 1-4 As shown, the present invention provides a method for forming a large-volume thin-walled steel inner liner by using 30CrMo steel plate through multiple deep drawing and annealing processes to form a thin-walled cup-shaped body with a wall thickness of 3.5mm. After the thin-walled cup-shaped body is shaped to a fixed length and with the opening aligned, it is formed by hot spinning.

[0033] This invention features a simple structure, a scientifically sound design, and ease of use. It utilizes 30CrMo steel plate, which undergoes multiple deep drawing and annealing processes to create a thin-walled cup-shaped body with a wall thickness of 3.5mm. After the cup-shaped body is cut to a fixed length and aligned at the rim, it is then shaped by hot spinning. The entire spinning and sizing process is optimized through temperature control and spinning passes to achieve the sizing of a large-volume thin-walled steel inner liner.

[0034] Example 2, as Figure 1-4 As shown, this invention provides a method for forming a large-volume thin-walled steel inner liner with a tapered opening. The method involves using 30CrMo steel plate, which undergoes multiple deep drawing and annealing processes to create a 3.5mm thick thin-walled cup-shaped body. After the thin-walled cup-shaped body is cut to a fixed length and aligned at the opening, it is then formed by hot spinning. The method includes the following steps:

[0035] Step 1: The 30CrMo steel plate is drawn into a rough billet through multiple deep drawing processes;

[0036] Step 2: After the rough blank is cut with a saw, it is formed into a thin cup shape;

[0037] Step 3: Place the thin cup-shaped body into an induction furnace for heating;

[0038] Step 4: After heating is complete, transfer the thin cup-shaped body into a spinning machine for spinning and shaping.

[0039] This embodiment 2, based on embodiment 1, provides specific steps for the forming method of a large-volume thin-walled steel inner liner. These specific steps are as follows:

[0040] Step 1: The 30CrMo steel plate is drawn into a rough billet through multiple deep drawing processes;

[0041] Step 2: After the rough blank is cut with a saw, it is formed into a thin cup shape;

[0042] Step 3: Place the thin cup-shaped body into an induction furnace for heating;

[0043] Step 4: After heating is complete, transfer the thin cup-shaped body into a spinning machine for spinning and shaping.

[0044] This invention, through the above steps, uses 30CrMo steel plate to produce a thin-walled cup-shaped body with a wall thickness of 3.5mm after multiple deep drawing and annealing processes. The thin-walled cup-shaped body is then shaped to a fixed length and with a flush opening, and then hot-spinned to achieve the desired opening. The entire hot-spinning and closing process is optimized through temperature control and spinning passes to achieve the closing of a large-volume thin-walled steel inner liner.

[0045] Example 3, as Figure 1-4 As shown, this invention provides a method for forming a large-volume thin-walled steel inner liner with a tapered opening. The method involves using 30CrMo steel plate, which undergoes multiple deep drawing and annealing processes to create a 3.5mm thick thin-walled cup-shaped body. After the thin-walled cup-shaped body is cut to a fixed length and aligned at the opening, it is then formed by hot spinning. The method includes the following steps:

[0046] Step 1: The 30CrMo steel plate is drawn into a rough billet through multiple deep drawing processes;

[0047] Step 2: After the rough blank is cut with a saw, it is formed into a thin cup shape;

[0048] Step 3: Place the thin cup-shaped body into an induction furnace for heating;

[0049] Step 4: After heating is complete, transfer the thin cup-shaped body into a spinning machine for spinning and shaping.

[0050] The wall thickness of the thin cup-shaped body is 3.5 mm.

[0051] Based on Example 2, this embodiment 3 provides a more preferred structure for the thin cup-shaped body, specifically: the wall thickness of the thin cup-shaped body is 3.5 mm. The thinner wall thickness of the thin cup-shaped body can reduce the overall weight of the steel inner liner and increase its volume.

[0052] Example 4, as Figure 1-4 As shown, this invention provides a method for forming a large-volume thin-walled steel inner liner with a tapered opening. The method involves using 30CrMo steel plate, which undergoes multiple deep drawing and annealing processes to create a 3.5mm thick thin-walled cup-shaped body. After the thin-walled cup-shaped body is cut to a fixed length and aligned at the opening, it is then formed by hot spinning. The method includes the following steps:

[0053] Step 1: The 30CrMo steel plate is drawn into a rough billet through multiple deep drawing processes;

[0054] Step 2: After the rough blank is cut with a saw, it is formed into a thin cup shape;

[0055] Step 3: Place the thin cup-shaped body into an induction furnace for heating;

[0056] Step 4: After heating is complete, transfer the thin cup-shaped body into a spinning machine for spinning and shaping.

[0057] In step 3, when the thin cup-shaped body is heated by an induction furnace, the opening of the thin cup-shaped body is inserted into the induction furnace for heating, with an insertion length of 500 mm.

[0058] Preferably, the heating temperature is 1140-1180℃;

[0059] Preferably, the rotational speed of the thin cup-shaped body in the medium-frequency furnace is 6 rad / min.

[0060] Based on Example 2, this Example 4 provides more preferred heating conditions for heating the thin cup-shaped body. Specifically, in step 3, when the thin cup-shaped body is heated by an induction furnace, the mouth of the thin cup-shaped body is inserted into the induction furnace for heating, with an insertion length of 500mm.

[0061] Preferably, the heating temperature is 1140-1180℃;

[0062] Preferably, the rotational speed of the thin cup-shaped body in the medium-frequency furnace is 6 rad / min. This design allows the thin cup-shaped body to be better spun and formed.

[0063] Example 5, as Figure 1-4 As shown, this invention provides a method for forming a large-volume thin-walled steel inner liner with a tapered opening. The method involves using 30CrMo steel plate, which undergoes multiple deep drawing and annealing processes to create a 3.5mm thick thin-walled cup-shaped body. After the thin-walled cup-shaped body is cut to a fixed length and aligned at the opening, it is then formed by hot spinning. The method includes the following steps:

[0064] Step 1: The 30CrMo steel plate is drawn into a rough billet through multiple deep drawing processes;

[0065] Step 2: After the rough blank is cut with a saw, it is formed into a thin cup shape;

[0066] Step 3: Place the thin cup-shaped body into an induction furnace for heating;

[0067] Step 4: After heating is complete, transfer the thin cup-shaped body into a spinning machine for spinning and shaping.

[0068] In step 4, when the thin cup-shaped body is transferred into the spinning machine, after the temperature of the thin cup-shaped body in the medium frequency furnace reaches the set temperature, the heating is stopped, and then the thin cup-shaped body is clamped and transferred by a robotic arm and mounted on the spinning machine.

[0069] Based on Example 2, Example 5 provides a more preferred method for transferring the thin cup-shaped body into the spinning machine. Specifically, in step 4, when transferring the thin cup-shaped body into the spinning machine, after the body reaches the set temperature in the medium-frequency furnace, the heating is stopped, and then a robotic arm is used to clamp and transfer the thin cup-shaped body onto the spinning machine. This design makes the transfer more efficient and safer.

[0070] Example 6, as Figure 1-4 As shown, this invention provides a method for forming a large-volume thin-walled steel inner liner with a tapered opening. The method involves using 30CrMo steel plate, which undergoes multiple deep drawing and annealing processes to create a 3.5mm thick thin-walled cup-shaped body. After the thin-walled cup-shaped body is cut to a fixed length and aligned at the opening, it is then formed by hot spinning. The method includes the following steps:

[0071] Step 1: The 30CrMo steel plate is drawn into a rough billet through multiple deep drawing processes;

[0072] Step 2: After the rough blank is cut with a saw, it is formed into a thin cup shape;

[0073] Step 3: Place the thin cup-shaped body into an induction furnace for heating;

[0074] Step 4: After heating is complete, transfer the thin cup-shaped body into a spinning machine for spinning and shaping.

[0075] In step 4, before the thin cup-shaped body is spun and shaped in the spinning machine, the thin cup-shaped body is first gripped by the spinning machine's jaws, and three heat guns are fixed on the spinning machine's rotating wheel and ignited to heat the thin cup-shaped body. Then the spinning machine's rotating wheel is pressed down to begin spun and shaped the thin cup-shaped body.

[0076] Based on Example 2, this embodiment 6 provides a more preferred preparation method for the spinning and sealing of a thin cup-shaped body. Specifically, in step 4, before the thin cup-shaped body is spun and sealed in the spinning machine, the thin cup-shaped body is first gripped by the spinning machine's jaws. Three heat guns are fixed on the spinning machine's rotating wheel and ignited to heat the thin cup-shaped body. Only then is the spinning machine's rotating wheel pressed down to begin sealing the thin cup-shaped body. This design improves the efficiency and quality of the spinning and sealing process.

[0077] Example 7, as Figure 1-4 As shown, this invention provides a method for forming a large-volume thin-walled steel inner liner with a tapered opening. The method involves using 30CrMo steel plate, which undergoes multiple deep drawing and annealing processes to create a 3.5mm thick thin-walled cup-shaped body. After the thin-walled cup-shaped body is cut to a fixed length and aligned at the opening, it is then formed by hot spinning. The method includes the following steps:

[0078] Step 1: The 30CrMo steel plate is drawn into a rough billet through multiple deep drawing processes;

[0079] Step 2: After the rough blank is cut with a saw, it is formed into a thin cup shape;

[0080] Step 3: Place the thin cup-shaped body into an induction furnace for heating;

[0081] Step 4: After heating is complete, transfer the thin cup-shaped body into a spinning machine for spinning and shaping.

[0082] In step 4, before the thin cup-shaped body is spun and shaped in the spinning machine, the thin cup-shaped body is first gripped by the spinning machine's jaws, and three heat guns are fixed on the spinning machine's rotating wheel and ignited to heat the thin cup-shaped body. Then the spinning machine's rotating wheel is pressed down to begin spun and shaped the thin cup-shaped body.

[0083] During the process of closing the thin cup-shaped body, in addition to using three heat guns fixed on the spinning machine wheel to heat the thin cup-shaped body throughout the process, it is also necessary to manually hold one heat gun for manual heating, and remove the manual heating when the bottle mouth is exited.

[0084] Based on Example 6, Example 7 provides a more preferred method for spinning and sealing the cup shape. Specifically, during the sealing process of the thin cup shape, in addition to using three heat guns fixed on the spinning machine's rollers to provide continuous heating, a manual heat gun is also required, which is removed when the cup exits the nozzle. This design improves the efficiency and quality of spinning and sealing.

[0085] Example 8, as Figure 1-4 As shown, this invention provides a method for forming a large-volume thin-walled steel inner liner with a tapered opening. The method involves using 30CrMo steel plate, which undergoes multiple deep drawing and annealing processes to create a 3.5mm thick thin-walled cup-shaped body. After the thin-walled cup-shaped body is cut to a fixed length and aligned at the opening, it is then formed by hot spinning. The method includes the following steps:

[0086] Step 1: The 30CrMo steel plate is drawn into a rough billet through multiple deep drawing processes;

[0087] Step 2: After the rough blank is cut with a saw, it is formed into a thin cup shape;

[0088] Step 3: Place the thin cup-shaped body into an induction furnace for heating;

[0089] Step 4: After heating is complete, transfer the thin cup-shaped body into a spinning machine for spinning and shaping.

[0090] In step 4, when spinning and sealing the thin cup-shaped body, 15 necking processes, 15 thickening processes, 4 nozzle-extrusion processes, and 1 shaping process are required to complete the sealing process.

[0091] Based on Example 2, this embodiment 8 provides a more preferred spinning and necking method for thin cup-shaped bodies. Specifically, in step 4, when spinning and necking the thin cup-shaped body, 15 necking processes, 15 thickening processes, 4 spouting processes, and 1 shaping process are required to complete the necking process. With this design, the entire spinning and necking process, through temperature control and optimization of spinning processes, achieves the necking of large-volume thin-walled steel inner liners.

[0092] Example 9, as Figure 1-4As shown, this invention provides a method for forming a large-volume thin-walled steel inner liner with a tapered opening. The method involves using 30CrMo steel plate, which undergoes multiple deep drawing and annealing processes to create a 3.5mm thick thin-walled cup-shaped body. After the thin-walled cup-shaped body is cut to a fixed length and aligned at the opening, it is then formed by hot spinning. The method includes the following steps:

[0093] Step 1: The 30CrMo steel plate is drawn into a rough billet through multiple deep drawing processes;

[0094] Step 2: After the rough blank is cut with a saw, it is formed into a thin cup shape;

[0095] Step 3: Place the thin cup-shaped body into an induction furnace for heating;

[0096] Step 4: After heating is complete, transfer the thin cup-shaped body into a spinning machine for spinning and shaping.

[0097] In step 4, during the spinning and sealing process of the thin cup-shaped body, multiple small spinning passes, material quantity, and stable heat replenishment measures are adopted to reduce the risk of edge turning and wrinkling during the spinning process of the thin cup-shaped body.

[0098] Based on Example 2, this embodiment 9 provides a more preferred spinning and sealing method for thin cup-shaped bodies. Specifically, in step 4, during the spinning and sealing process of the thin cup-shaped body, multiple small spinning passes, low material volume, and stable heat replenishment measures are used to reduce the risk of edge turning and wrinkling during the spinning process. This design improves the efficiency and quality of spinning and sealing.

[0099] Example 10, as Figure 1-4 As shown, this invention provides a method for forming a large-volume thin-walled steel inner liner with a tapered opening. The method involves using 30CrMo steel plate, which undergoes multiple deep drawing and annealing processes to create a 3.5mm thick thin-walled cup-shaped body. After the thin-walled cup-shaped body is cut to a fixed length and aligned at the opening, it is then formed by hot spinning. The method includes the following steps:

[0100] Step 1: The 30CrMo steel plate is drawn into a rough billet through multiple deep drawing processes;

[0101] Step 2: After the rough blank is cut with a saw, it is formed into a thin cup shape;

[0102] Step 3: Place the thin cup-shaped body into an induction furnace for heating;

[0103] Step 4: After heating is complete, transfer the thin cup-shaped body into a spinning machine for spinning and shaping.

[0104] The spinning machine includes a spinning machine base 1, a main shaft 2 mounted on the spinning machine base 1 and connected to a rotary drive device, a chuck 3 mounted on the main shaft 2 for gripping a thin cup-shaped body 4 fitted on the main shaft 2 so that the thin cup-shaped body 4 rotates synchronously with the main shaft 2, a slide rail 5 mounted on the spinning machine base 1, a spinning carriage 6 slidably mounted on the slide rail 5, a spinning wheel shaft 7 rotatably mounted on the spinning carriage 6 and connected to the rotary drive device, and a spinning wheel 8 mounted on the spinning wheel shaft 7 for cooperating with the main shaft 2 to spin the thin cup-shaped body 4; three heat guns A9 are mounted side by side on the spinning wheel 8, and a heat gun B10 for manual heat replenishment is also placed next to the spinning machine base 1.

[0105] Based on Embodiment 2, this embodiment 10 provides a more preferred structure for the spinning machine, specifically: the spinning machine includes a spinning machine base 1, a main shaft 2 mounted on the spinning machine base 1 and connected to a rotary drive device, a chuck 3 mounted on the main shaft 2 for gripping a thin cup-shaped body 4 fitted onto the main shaft 2 so that the thin cup-shaped body 4 rotates synchronously with the main shaft 2, a slide rail 5 mounted on the spinning machine base 1, a spinning carriage 6 slidably mounted on the slide rail 5, a spinning wheel shaft 7 rotatably mounted on the spinning carriage 6 and connected to the rotary drive device, and a spinning wheel 8 mounted on the spinning wheel shaft 7 for working with the main shaft 2 to spin the thin cup-shaped body 4; three heat guns A9 are mounted side by side on the spinning wheel 8, and a heat gun B10 for manual heat replenishment is also placed next to the spinning machine base 1. This design can improve the spinning finishing efficiency and quality.

[0106] This invention provides a method for forming a large-capacity thin-walled steel inner liner. The main process involves using 30CrMo steel sheet, which is subjected to multiple deep drawing and annealing processes to create a 3.5mm thick thin-walled cup-shaped body. After the cup-shaped body is cut to a fixed length and then trimmed, it is formed by hot spinning. The entire spinning and trimming process is optimized through temperature control and spinning passes to achieve the desired forming of the large-capacity thin-walled steel inner liner. The method mainly involves: drawing the original sheet multiple times, then trimming it with a saw to create a 3.5mm thick thin-walled cup-shaped body; heating the cup-shaped body in a medium-frequency furnace at a length of 500mm and a temperature of 1140-1180℃, with a rotation speed of 6 rad / min; after reaching the desired temperature, the heating is stopped, and a robotic arm grips and transfers the cup-shaped body onto a spinning machine; the spinning machine's jaws are tightened, and three clamps fixed to the spinning wheel... The heat exchanger is ignited for heat exchange, and the spinning wheel presses down to begin the necking process. The spinning wheel program completes the necking with 15 passes of necking, 15 passes of thickening, 4 passes of nozzle exit, and 1 pass of shaping. During the necking process, in addition to the three heat exchangers on the spinning wheel providing continuous heat exchange, a manual heat exchanger is used for manual heat exchange. The manual heat exchanger is removed when the bottle nozzle exits. The spinning process employs multiple small spinning passes, a small amount of material, and a stable heat exchanger mechanism to reduce the risk of edge flipping and wrinkling during the spinning of thin-walled inner liners. The spinning device includes at least a medium-frequency heating device, a robotic arm, a spinning necking device, an automatic heat exchanger mechanism, and a manual heat exchanger.

[0107] This invention fills a gap in the domestic technology for forming and closing of large-capacity thin-walled steel inner liner; the thin-walled inner liner has a high success rate in closing, which can effectively reduce the amount of steel plate used and reduce the cost of the product; it promotes the development of lightweight products, which is conducive to reducing vehicle weight and thus reducing vehicle pollution emissions.

[0108] Finally, it should be noted that the above embodiments are merely preferred embodiments of the present invention used to illustrate the technical solutions of the present invention, and are not intended to limit the invention, nor are they intended to limit the patent scope of the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention. That is to say, any changes or refinements made to the main design concept and spirit of the present invention that are not of substantial significance, but whose technical problems are still consistent with the present invention, should be included within the protection scope of the present invention. In addition, the direct or indirect application of the technical solutions of the present invention to other related technical fields are similarly included within the patent protection scope of the present invention.

Claims

1. A method for forming a large-volume thin-walled steel inner liner, characterized in that, A thin-walled cup-shaped body with a wall thickness of 3.5 mm is made from 30CrMo steel sheet through multiple deep drawing and annealing processes. After the thin-walled cup-shaped body is cut to a fixed length and then shaped by hot spinning, the opening is closed. The method includes the following steps: Step 1: The 30CrMo steel plate is formed into a rough billet through multiple deep drawing and annealing processes; Step 2: After the rough blank is cut with a saw, it is formed into a thin cup-shaped body with a wall thickness of 3.5mm; Step 3: Place the thin cup-shaped body into the medium frequency furnace for heating. The length of the opening of the thin cup-shaped body extending into the medium frequency furnace is 500 mm. The heating temperature is 1140-1180℃. The rotation speed of the thin cup-shaped body in the medium frequency furnace is 6 rad / min. Step 4: After heating is complete, a robotic arm is used to transfer the thin cup shape into and clamp it onto the spinning machine. The spinning machine's jaws first grip the thin cup shape, and three heat guns are fixed on the spinning machine's rotating wheel and ignited to heat the thin cup shape. Then, the spinning machine's rotating wheel is pressed down to begin closing the thin cup shape. The spinning closing process includes 15 necking processes, 15 thickening processes, 4 spouting processes, and 1 shaping process. During the closing process of the thin cup shape, in addition to using the three heat guns fixed on the spinning machine's rotating wheel to heat the thin cup shape throughout the process, a manual heat gun is also required for manual heating. The manual heating is removed when the bottle spout is exited. The method employs multiple small-batch spinning passes, material volume, and stable heat replenishment measures to reduce the risk of edge flipping and wrinkling during the spinning process of thin cup-shaped bodies.

2. The method for forming a large-volume thin-walled steel inner liner according to claim 1, characterized in that, The spinning machine includes a spinning machine base (1), a main shaft (2) mounted on the spinning machine base (1) and connected to a rotary drive device, a chuck (3) mounted on the main shaft (2) for gripping the thin cup-shaped body (4) fitted on the main shaft (2) so that the thin cup-shaped body (4) rotates synchronously with the main shaft (2), a slide rail (5) mounted on the spinning machine base (1), a spinning carriage (6) slidably mounted on the slide rail (5), a spinning wheel shaft (7) rotatably mounted on the spinning carriage (6) and connected to the rotary drive device, and a spinning wheel (8) mounted on the spinning wheel shaft (7) for working with the main shaft (2) to spin the thin cup-shaped body (4); three heat guns A (9) are mounted side by side on the spinning wheel (8), and a heat gun B (10) for manual heat replenishment is also placed next to the spinning machine base (1).

Images