Liquid receiver
By optimizing the connection between the end cap and the cylinder of the liquid reservoir through laser welding and stepped structure, the problems of high welding cost and insufficient strength were solved, achieving the effects of cost saving and strong welding.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- ZHEJIANG DUNAN ARTIFICIAL ENVIRONMENT CO LTD
- Filing Date
- 2025-10-20
- Publication Date
- 2026-06-04
AI Technical Summary
In existing liquid storage devices, the welding cost between the end cap and the cylinder is high and the welding is not strong. In particular, when brazing or laser welding is used, it is difficult to ensure sufficient penetration and welding strength.
Laser welding is used to connect the cylinder and the end cap. By setting a stepped structure and flange holes between the end cap and the cylinder, the overlapping area is reduced, the penetration depth is ensured and the weld strength is improved. At the same time, stainless steel or carbon steel materials are used to reduce costs.
It significantly reduces material costs, improves the welding strength and reliability of the end cap and cylinder, and ensures the stability and economy of the liquid reservoir.
Smart Images
Figure CN2025128623_04062026_PF_FP_ABST
Abstract
Description
reservoir
[0001] Related applications
[0002] This application claims priority to Chinese patent application No. 202422943218.2, filed on November 29, 2024, entitled "Liquid Container", the entire contents of which are incorporated herein by reference. Technical Field
[0003] This application relates to the field of liquid storage devices for refrigeration systems, and in particular to a liquid storage device. Background Technology
[0004] In a refrigeration system, a liquid receiver is used to store the liquid refrigerant of the refrigeration system. The liquid receiver includes a cylinder and an end cap. The end cap is used to form a cavity between itself and the cylinder, and the cavity is used to store the liquid refrigerant.
[0005] The end cap and cylinder are typically fixed together by brazing. This requires an overlap of 8mm to 10mm between the end cap and cylinder to accommodate the molten solder, but this results in higher costs for both the end cap and cylinder. Alternatively, the end cap and cylinder can be fixed together by laser welding. Laser welding is a self-fusion welding process, which allows for a shorter overlap and thus saves costs. However, the relevant reservoir cannot guarantee sufficient weld depth or a strong weld between the end cap and cylinder. Summary of the Invention
[0006] According to an embodiment of this application, a liquid reservoir is provided.
[0007] A liquid reservoir includes a cylinder and a second end cap. The cylinder has a first opening, and the second end cap has a second port. The second port is inserted into the cylinder through the first opening and fixed to the cylinder by laser welding. The extension length of the overlapping area between the second port and the cylinder is L1, where 2mm≤L1≤3mm.
[0008] In one embodiment, the outer diameter of the second end cap decreases at the second port, so that the second end cap forms a first step structure at a transition position near the second port, the first step structure being oriented toward the cylinder; when the second port is inserted into the cylinder through the first opening, the first step structure engages with the edge stop of the first opening.
[0009] In one embodiment, the reservoir further includes a first end cap, and the cylinder has a second opening opposite to the first opening. The first end cap is configured to have a connecting flare, which is fitted onto the outer periphery of the cylinder at the second opening and fixed to the cylinder by laser welding. The extension length of the overlapping area between the connecting flare and the cylinder is L. 21 And 2mm≤L21 ≤4mm.
[0010] In one embodiment, the reservoir further includes a filter screen, and the inner diameter of the first end cap increases at the connecting flare so that the first end cap forms a second step structure at the transition position near the connecting flare. The second step structure is disposed towards the cylinder, and the filter screen is fixed to the second step structure. When the connecting flare is sleeved on the outer periphery of the cylinder, the cylinder abuts against the filter screen.
[0011] In one embodiment, the reservoir further includes a first end cap, the cylinder has a second opening opposite to the first opening, the first end cap has a first port, the first port is inserted into the cylinder through the second opening and fixed to the cylinder by laser welding, wherein the length of the overlapping area between the first port and the cylinder is L. 22 2mm≤L 22 ≤3mm; The outer diameter of the first end cap decreases at the first port so that the first end cap forms a third step structure at the transition position near the first port. The third step structure is set towards the cylinder. When the first port is inserted into the cylinder through the second opening, the third step structure cooperates with the edge stop of the second opening.
[0012] In one embodiment, the reservoir further includes a filter screen, and both the first end cap and the second end cap are configured to have a second port. The inner wall of the cylinder near the first end cap is provided with an assembly groove, and the filter screen is snapped into the assembly groove.
[0013] In one embodiment, the liquid reservoir further includes an inlet pipe and an outlet pipe, and the cylinder, the first end cap and the second end cap surround to form a cavity; the first end cap has a first mounting hole, the inlet pipe is installed in the first mounting hole and communicates with the cavity, the second end cap has a second mounting hole, and the outlet pipe is installed in the second mounting hole and communicates with the cavity.
[0014] In one embodiment, the first mounting hole is configured as a flanged hole, with the flange of the first mounting hole protruding from the surface of the first end cap; and / or, the second mounting hole is configured as a flanged hole, with the flange of the second mounting hole protruding from the surface of the second end cap.
[0015] In one embodiment, the intake pipe has an installation section, at least a portion of which is inserted into a first mounting hole and fixed to the hole wall of the first mounting hole by laser welding; wherein the depth of the installation section inserted into the first mounting hole is L3, 2mm≤L3≤4mm; and the length of the installation section outside the first mounting hole is L4, 1mm≤L4.
[0016] In one embodiment, the vent pipe includes a straight section and a curved section. The curved section is located outside the cavity. One end of the straight section is connected to the curved section, and the other end extends into the cavity through a second mounting hole. The straight section is fixed to the wall of the second mounting hole by laser welding. The overlap length between the straight section and the wall of the second mounting hole is L5, where 2mm ≤ L5 ≤ 4mm. The end of the straight section near the curved section extends out of the second mounting hole, and the length of the end of the straight section near the curved section extending out of the second mounting hole is L6, where 1mm ≤ L6.
[0017] In one embodiment, the inlet pipe and outlet pipe are both made of stainless steel or carbon steel, and the thickness of the inlet pipe and outlet pipe is between 0.8 mm and 1.2 mm; the thickness of the cylinder, the first end cap and the second end cap is between 1.5 mm and 2.5 mm.
[0018] Details of one or more embodiments of this application are set forth in the following drawings and description. Other features, objects, and advantages of this application will become apparent from the specification, drawings, and claims. Attached Figure Description
[0019] To better describe and illustrate embodiments and / or examples of the inventions disclosed herein, reference may be made to one or more accompanying drawings. Additional details or examples used to describe the drawings should not be considered as limiting the scope of any of the disclosed inventions, the currently described embodiments and / or examples, or the best mode of these inventions as currently understood.
[0020] Figure 1 is a cross-sectional view of the reservoir according to Embodiment 1 provided in this application.
[0021] Figure 2 is a cross-sectional view of the liquid reservoir of Embodiment 2 provided in this application.
[0022] Reference numerals: 100, reservoir; 10, cylinder; 111, first opening; 112, second opening; 12, assembly groove; 20, first end cap; 21, first mounting hole; 22, connecting flare; 23, second step structure; 24, first port; 25, third step structure; 30, second end cap; 31, second port; 32, first step structure; 33, second mounting hole; 40, cavity; 50, air inlet pipe; 51, mounting section; 52, intermediate section; 53, interface section; 60, air outlet pipe; 61, straight pipe section; 62, bent pipe section; 70, filter screen. Detailed Implementation
[0023] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.
[0024] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application's specification are for illustrative purposes only and do not represent the only possible implementation.
[0025] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0026] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0027] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items.
[0028] This application provides a liquid reservoir 100, which includes a cylindrical body 10, a first end cap 20 and a second end cap 30. The two ends of the cylindrical body 10 have a first opening 111 and a second opening 112, respectively. The first end cap 20 is connected to the second opening 112, and the second end cap 30 is connected to the first opening 111. A cavity 40 is formed between the first end cap 20, the second end cap 30 and the cylindrical body 10.
[0029] Example 1
[0030] Please refer to Figure 1. The second end cap 30 is configured to have a second port 31. The second port 31 is inserted into the cylinder 10 through the first opening 111 and fixed to the cylinder 10 by laser welding. The extension length of the overlapping area between the second port 31 and the cylinder 10 is L1, and 2mm≤L1≤4mm.
[0031] It should be noted that laser welding uses a laser beam as its energy source. The laser beam acts directly on the surface of the workpiece, causing localized melting to form a molten pool. After cooling, a weld is formed without the need for additional solder or flux. Therefore, using laser welding to connect the second end cap 30 and the cylinder 10 eliminates the need for an excessively long overlap area to accommodate the molten solder. This allows for a shorter overlap length between the second end cap 31 and the cylinder 10, i.e., L1 ≤ 4mm. Compared to related structures that require an 8mm to 10mm overlap between the end cap and the cylinder, this significantly reduces the material cost of both the second end cap 30 and the cylinder 10. Furthermore, setting L1 to 2mm ≤ L1 helps ensure a 1mm to 2mm weld depth between the second end cap 30 and the cylinder 10, ensuring a secure weld.
[0032] Furthermore, the outer diameter of the second end cap 30 decreases at the second port 31, so that the second end cap 30 forms a first stepped structure 32 at the transition position near the second port 31, with the first stepped structure 32 facing the cylinder 10. When the second port 31 of the second end cap 30 is inserted into the cylinder 10 through the first opening 111, the first stepped structure 32 engages with the corresponding edge of the first opening 111. It can be understood that during the assembly of the second end cap 30 and the cylinder 10, the first stepped structure 32 and the edge of the first opening 111 of the cylinder 10 play a role in quick installation and positioning.
[0033] Optionally, the first step structure 32 can be formed by machining the outer wall of the second end cap 30. Specifically, the wall thickness of the second port 31 can be reduced by machining, and the difference in wall thickness between the second port 31 and the adjacent part forms the first step structure 32. Alternatively, the end of the second end cap 30 can be contracted inward by a closing or extrusion process to form the second port 31 and the first step structure 32.
[0034] The first end cap 20 is configured with a connecting flare 22, which is fitted onto the outer periphery of the cylinder 10 at the second opening 112 and fixed to the cylinder 10 by laser welding. The extension length of the overlapping area between the connecting flare 22 and the cylinder 10 is L. 21 And 2mm≤L 21 ≤4mm. Similarly, the first end cap 20 is fixed to the cylinder 10 at the connecting flared end 22 by laser welding. Since laser welding is a self-fusion welding, it does not require the use of solder, and therefore does not need to reserve an excessively long overlap area to accommodate the molten solder. This allows for a relatively short overlap area between the connecting flared end 22 and the cylinder 10, i.e., L. 21 ≤4mm, thus, compared to related structures that require an 8mm to 10mm overlap between the end cap and the cylinder, significantly reducing the material cost of the first end cap 20 and the cylinder 10. Furthermore, setting 2mm ≤L... 21 This helps to ensure that a 1mm to 2mm weld depth is formed between the first end cap 20 and the cylinder 10, so that the first end cap 20 and the cylinder 10 are firmly welded.
[0035] The reservoir 100 also includes a filter screen 70. The inner diameter of the first end cap 20 increases at the connecting flare 22, so that the first end cap 20 forms a second step structure 23 at the transition position near the connecting flare 22. The second step structure 23 is positioned towards the cylinder 10, and the filter screen 70 is fixed to the second step structure 23. When the connecting flare 22 is fitted onto the outer periphery of the cylinder 10, the cylinder 10 abuts against the filter screen 70. By having the cylinder 10 abut against the filter screen 70, the filter screen 70 is installed more securely.
[0036] Specifically, during the assembly of the liquid reservoir 100, the filter screen 70 can be welded and fixed to the second step structure 23 first, and then the first end cap 20 can be fitted onto the outer periphery of the cylinder 10 through the connecting flare 22, so that the cylinder 10 abuts against the filter screen 70. Finally, the connecting flare 22 and the cylinder 10 can be fixed by laser welding.
[0037] The liquid reservoir 100 also includes an inlet pipe 50 and an outlet pipe 60. A first end cap 20 has a first mounting hole 21, through which the inlet pipe 50 is installed and connects to the cavity 40. A second end cap 30 has a second mounting hole 33, through which the outlet pipe 60 is installed and connects to the cavity 40. A filter screen 70 is used to filter the medium entering the cavity 40 via the inlet pipe 50.
[0038] The first mounting hole 21 is configured as a flanged hole, with the flange of the first mounting hole 21 protruding from the surface of the first end cap 20; and / or, the second mounting hole 33 is configured as a flanged hole, with the flange of the second mounting hole 33 protruding from the surface of the second end cap 30. That is, the first mounting hole 21 can be configured as a flanged hole, with the flange of the first mounting hole 21 protruding from the surface of the first end cap 20, which increases the contact area between the wall of the first mounting hole 21 and the air intake pipe 50, thereby allowing the air intake pipe 50 to be more securely mounted in the first mounting hole 21; or, the second mounting hole 33 can be configured as a flanged hole, with the flange of the second mounting hole 33 protruding from the surface of the second end cap 30, which increases the contact area between the wall of the second mounting hole 33 and the air outlet pipe 60, thereby allowing the air outlet pipe 60 to be more securely mounted in the second mounting hole 33; or, both the first mounting hole 21 and the second mounting hole 33 can be configured as flanged holes.
[0039] The flange of the first mounting hole 21 can extend toward the interior of the cavity 40 or toward the direction away from the cavity 40. Similarly, the flange of the second mounting hole 33 can extend toward the interior of the cavity 40 or toward the direction away from the cavity 40.
[0040] For example, in one embodiment, as shown in FIG1, the flange of the first mounting hole 21 extends toward the direction away from the cavity 40, and the second mounting hole 33 extends toward the interior of the cavity 40.
[0041] Furthermore, the intake pipe 50 has an installation section 51, at least a portion of which is inserted into the first mounting hole 21 and fixed to the hole wall of the first mounting hole 21 by laser welding. The depth to which the installation section 51 is inserted into the first mounting hole 21 is L3, where 2mm ≤ L3 ≤ 4mm. It is understood that setting 2mm ≤ L3 helps ensure the weld penetration between the cylinder 10 and the intake pipe 50 is between 1mm and 2mm, and setting L3 ≤ 4mm helps save material costs for both the cylinder 10 and the intake pipe 50. For example, L3 can be 2mm, 3mm, 3.5mm, or 4mm, etc. The length of the installation section 51 outside the first mounting hole 21 is L4, where 1mm ≤ L4. This design facilitates the melting of the flanged end of the first mounting hole 21 protruding from the surface of the installation section 51, thereby facilitating the fixation of the intake pipe 50 to the cylinder 10 by laser welding.
[0042] The intake pipe 50 also includes an intermediate section 52 and an interface section 53. The mounting section 51 and the interface section 53 are located at opposite ends of the intermediate section 52, and the diameters of both the mounting section 51 and the interface section 53 are larger than the diameter of the intermediate section 52. That is, the intake pipe 50 is flared at both ends to form the interface section 53 and the mounting section 51, respectively. Thus, when an external fitting is inserted into the interface section 53, it is stopped at the junction of the interface section 53 and the intermediate section 52. The mounting section 51, the intermediate section, and the interface section 53 are a single integrated structure.
[0043] The exhaust pipe 60 includes a straight section 61 and a bent section 62. The bent section 62 is located outside the cavity 40. One end of the straight section 61 is connected to the bent section 62, and the other end of the straight section 61 extends into the cavity 40 through the second mounting hole 33. The straight section 61 is fixed to the wall of the second mounting hole 33 by laser welding. The overlap length between the straight section 61 and the wall of the second mounting hole 33 is L5, where 2mm ≤ L5 ≤ 4mm. It is understood that setting 2mm ≤ L5 helps ensure that the laser welding depth between the cylinder 10 and the exhaust pipe 60 is between 1mm and 2mm, and setting L5 ≤ 4mm helps save material costs for the cylinder 10 and the exhaust pipe 60. Furthermore, the end of the straight section 61 near the bent section 62 extends out of the second mounting hole 33 by a length L6, where 1mm ≤ L6. This avoids the bending section 62 affecting the positioning of the laser welding gun when the exhaust pipe 60 rotates. The straight section 61 and the bending section 62 are integral structures.
[0044] Both the inlet pipe 50 and the outlet pipe 60 are made of stainless steel or carbon steel, and their thicknesses are between 0.8 mm and 1.2 mm. Using stainless steel or carbon steel for the inlet pipe 50 and the outlet pipe 60 reduces the material cost of the liquid reservoir 100. The thicknesses of the cylinder 10, the first end cap 20, and the second end cap 30 are all between 1.5 mm and 2.5 mm.
[0045] Example 2
[0046] Referring to Figure 2, the liquid reservoir 100 in this embodiment is similar to that in Embodiment 1, both including a cylinder 10, a first end cap 20, a second end cap 30, an air inlet pipe 50, an air outlet pipe 60, and a filter screen 70. The second end cap 30 is configured with a second port 31, which is inserted into the cylinder 10 through a first opening 111 and fixed to the cylinder 10 by laser welding. The overlapping area between the second port 31 and the cylinder 10 has an extension length L1, and 2mm ≤ L1 ≤ 4mm. The second end cap 30 also has a first step structure 32. The similarities will not be repeated here. The difference is that the first end cap 20 is configured with a first port 24, which is inserted into the cylinder 10 through a second opening 112 and fixed to the cylinder 10 by laser welding. The overlapping area between the first port 24 and the cylinder 10 has an extension length L1. 22 2mm≤L 22 ≤3mm.
[0047] Furthermore, the outer diameter of the first end cap 20 is reduced at the first port 24 so that the first end cap 20 forms a third step structure 25 at the transition position near the first port 24. The third step structure 25 is positioned towards the cylinder 10. When the first port 24 is inserted into the cylinder 10 through the second opening 112, the third step structure 25 engages with the edge stop of the second opening 112.
[0048] Furthermore, the installation method of the filter screen 70 is also different. The inner wall of the cylinder 10 near the first end cover 20 is provided with an assembly groove 12, and the filter screen 70 is snapped into the assembly groove 12. Specifically, the cylinder 10 contracts inward along its own radial direction to form two constrictions. The number of constrictions is two, and the two constrictions are distributed at intervals along the axial direction of the cylinder 10 and surround the assembly groove 12. In this way, the welding process between the filter screen 70 and the cylinder 10 is reduced.
[0049] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0050] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.
Claims
1. A reservoir characterized by, The liquid reservoir includes a cylindrical body and a second end cap. The cylindrical body has a first opening, and the second end cap has a second port. The second port is inserted into the cylindrical body through the first opening and is fixed to the cylindrical body by laser welding. The extension length of the overlapping area between the second port and the cylindrical body is L1, where 2mm≤L1≤3mm.
2. The reservoir of claim 1, wherein, The outer diameter of the second end cap decreases at the second port, so that the second end cap forms a first step structure at the transition position near the second port, and the first step structure is oriented toward the cylinder. When the second port is inserted into the cylinder through the first opening, the first stepped structure engages with the edge stop of the first opening.
3. The fluid reservoir of claim 1, wherein, The reservoir further includes a first end cap, and the cylinder has a second opening disposed opposite to the first opening; The first end cover is configured to have a connecting flange, the connecting flange is sleeved on the outer periphery of the barrel body at the second opening and is fixed with the barrel body by laser welding, wherein the extension length of the overlapping area between the connecting flange and the barrel body is L 21 , and 2mm≤L 21 ≤4mm.
4. The reservoir of claim 3, wherein, The liquid reservoir also includes a filter screen. The inner diameter of the first end cap increases at the connecting flare, so that the first end cap forms a second step structure at the transition position near the connecting flare. The second step structure is disposed towards the cylinder. The filter screen is fixed to the second step structure. When the connecting flare is sleeved on the outer periphery of the cylinder, the cylinder abuts against the filter screen.
5. The reservoir of claim 1, wherein, The reservoir further comprises a first end cover, the barrel has a second opening arranged opposite to the first opening, the first end cover has a first port, the first port is inserted into the barrel through the second opening and is fixed with the barrel by laser welding, wherein the length of the overlapping area between the first port and the barrel is L 22 , 2mm≤L 22 ≤3mm; The outer diameter of the first end cap decreases at the first port so that the first end cap forms a third step structure at the transition position near the first port. The third step structure is oriented toward the cylinder. When the first port is inserted into the cylinder through the second opening, the third step structure cooperates with the edge stop of the second opening.
6. The reservoir of claim 5, wherein, The liquid reservoir also includes a filter screen. Both the first end cap and the second end cap are configured to have a second port. The inner wall of the cylinder near the first end cap is provided with an assembly groove, and the filter screen is snapped into the assembly groove.
7. The reservoir of any of claims 3-6, wherein, The liquid reservoir also includes an air inlet pipe and an air outlet pipe, and the cylinder, the first end cap and the second end cap surround to form a cavity; The first end cap has a first mounting hole, the air inlet pipe is installed in the first mounting hole and communicates with the cavity, the second end cap has a second mounting hole, and the air outlet pipe is installed in the second mounting hole and communicates with the cavity.
8. The reservoir of claim 7, wherein, The first mounting hole is configured as a flanged hole, and the flange of the first mounting hole protrudes from the surface of the first end cap; And / or, the second mounting hole is configured as a flanged hole, wherein the flange of the second mounting hole protrudes from the surface of the second end cap.
9. The reservoir of claim 8, wherein, The intake pipe has an installation section, at least a portion of which is inserted into the first mounting hole and fixed to the hole wall of the first mounting hole by laser welding. Wherein, the depth to which the mounting segment is inserted into the first mounting hole is L3, 2mm≤L3≤4mm; the length of the mounting segment outside the first mounting hole is L4, 1mm≤L4.
10. The reservoir of claim 8, wherein, The vent pipe includes a straight section and a curved section. The curved section is located outside the cavity. One end of the straight section is connected to the curved section, and the other end extends into the cavity through the second mounting hole. The straight section is fixed to the wall of the second mounting hole by laser welding. The length of the overlap between the straight pipe section and the wall of the second mounting hole is L5, and 2mm≤L5≤4mm; the end of the straight pipe section close to the elbow pipe section extends out of the second mounting hole, and the length of the end of the straight pipe section close to the elbow pipe section extending out of the second mounting hole is L6, and 1mm≤L6.
11. The reservoir of claim 7, wherein, The material of the air inlet pipe and the air outlet pipe is configured as stainless steel or carbon steel, and the thickness of the air inlet pipe and the air outlet pipe is between 0.8mm and 1.2mm; the thickness of the cylinder body, the first end cover and the second end cover is between 1.5mm and 2.5mm.