High-pressure sealing cover for hydrogen cylinder connector

Abstract

The utility model relates to the technical field of a high-pressure sealing cover for a hydrogen cylinder interface, and discloses a high-pressure sealing cover for a hydrogen cylinder interface, which is integrally formed by a metal joint body and a plastic upper tank body through injection molding, and the bottom end face of the metal joint body is vertically upwards provided with a hole. According to the high-pressure sealing cover for the joint of the hydrogen cylinder, the hole is formed in the metal joint; the expansion of the metal is much smaller than that of the plastic, a gap is generated between the plastic and the metal under normal conditions, but the opposite effect generated by different thermal expansion degrees of the plastic and the metal joint is counteracted through the hole in the metal joint; meanwhile, no gap is generated, but more compact extrusion is realized, and the problem of high-pressure hydrogen leakage caused by expansion with heat and contraction with cold is solved; and meanwhile, as the structure is not sealed by threads or by means of mutual extrusion of external force, the service lives of plastic and metal are ensured, and the phenomena of metal fatigue and plastic aging are not easy to occur.

Description

Technical Field

[0001] The utility model relates to the technical field of high-pressure sealing covers for hydrogen cylinder interfaces, in particular to a high-pressure sealing cover for hydrogen cylinder interfaces. Background Art

[0002] All-composite high-pressure hydrogen cylinders are often made of a non-metallic polymer liner (such as high-density / high-molecular-weight polyethylene plastic) and an outer layer of carbon fiber or aramid fiber, and are often called Type IV high-pressure gas cylinders. In practical applications, the gas storage pressure is often required to reach 700 (70MPa) or even 1000 (100MPa) atmospheres. Since composite gas cylinders need to be connected to metal pressurization / pressure relief valves at the joints, how to prevent gas leakage at the joints is one of the key technical difficulties in the successful design and manufacture of (ultra-) high-pressure hydrogen cylinders.

[0003] Chinese patent CN206145427U discloses a design of a high-pressure gas cylinder with an aluminum-plastic composite structure liner; in the structure shown in the utility model report, the utility model inventor proposed to set an internal thread on the head of the gas cylinder and place a sealing ring on the shoulder of the gas cylinder and the injection-molded non-metallic cylinder to prevent gas leakage, but in practice people have found that the simple method of using such a sealing ring alone cannot effectively prevent the leakage of hydrogen at the joint or gas nozzle under ultra-high pressure (for example, above 700 atmospheres), and it is more prone to fatigue failure under high pressure and large temperature difference cyclic conditions.

[0004] Therefore, the utility model provides a high-pressure sealing cover for the interface of a hydrogen cylinder to solve the above-mentioned problems. Utility Model Content

[0005] Technical issues solved

[0006] In view of the deficiencies in the prior art, the utility model provides a high-pressure sealing cover for the interface of a hydrogen cylinder. Since this structure does not use threads or rely on external force to squeeze each other for sealing, the service life of plastic and metal is guaranteed, and metal fatigue and plastic aging are not prone to occur. This solves the problem that the simple method of the existing sealing ring cannot effectively prevent the leakage of hydrogen at the joint or gas nozzle under ultra-high pressure (for example, above 700 atmospheres), and it is more prone to fatigue failure under high pressure and large temperature difference cyclic conditions.

[0007] Technical Solution

[0008] To achieve the above object, the utility model provides the following technical solutions: a high-pressure sealing cover for the interface of a hydrogen cylinder, comprising a metal joint body and a plastic upper tank body formed by injection molding, wherein a hole is vertically opened on the bottom end surface of the metal joint body;

[0009] The holes are arranged in two groups, inside and outside, and each group of holes is evenly arranged in a circle on the bottom surface of the metal joint body;

[0010] Two groups of connection holes are horizontally opened in the bottom of the metal joint body, and the connection holes are evenly distributed along the radial direction of the metal joint body. The connection holes connect the corresponding inner and outer groups of holes.

[0011] Preferably, an inner wall at the top end of the metal joint body is provided with an internal thread.

[0012] Preferably, a metal round cap is arranged below the metal joint body, the top end surface of the metal round cap is welded to the bottom end surface of the metal joint body, and the metal round cap and the metal joint body form a metal dissimilar joint.

[0013] Preferably, two groups of injection holes A are evenly opened on the outer side of the bottom end of the metal joint body at positions corresponding to the connection holes, and the two groups of injection holes A are respectively connected to the inside of the corresponding connection holes.

[0014] Preferably, two groups of injection holes B are evenly opened on the outer side of the bottom end of the metal joint body at positions corresponding to the connecting holes, and the two groups of injection holes B are respectively connected to the inside of the corresponding connecting holes. Two injection grooves connected end to end are opened on the outer side of the bottom end of the metal joint body at positions corresponding to the two groups of injection holes B, and the inside of each injection groove is connected to the corresponding injection hole B.

[0015] Compared with the prior art, the utility model provides a high-pressure sealing cover for the interface of a hydrogen cylinder, which has the following beneficial effects:

[0016] 1. The hydrogen cylinder interface uses a high-pressure sealing cover. By designing holes on the metal joint, when the tank temperature rises, thermal expansion occurs. The expansion of metal is much smaller than that of plastic. Under normal circumstances, this will cause gaps between plastic and metal. However, this patent uses the holes inside the metal joint to offset the opposite effects of the plastic and metal joints due to different degrees of thermal expansion. At the same time, not only will there be no gaps, but they will be squeezed tighter. Conversely, the same principle applies when it shrinks in the cold. The plastic shrinks more and the metal joint will be wrapped tighter, solving the problem of high-pressure hydrogen leakage caused by thermal expansion and contraction. At the same time, since this structure does not use threads or rely on external force to squeeze each other to seal, the service life of plastic and metal is guaranteed, and metal fatigue and plastic aging are not prone to occur.

[0017] 2. The hydrogen cylinder interface uses a high-pressure sealing cover, which ensures that the plastic can fill any cavity in the mold through mechanical high-pressure extrusion of engineering plastics. In addition, since the injected plastic is squeezed in with high pressure, the plastic in the cavity is guaranteed to be firm and full, so that when the plastic enters the holes of the metal joint, it will form a large bonding extrusion force in the metal holes, thus preventing leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a three-dimensional schematic diagram of the main structure of the metal joint of the utility model;

[0019] Figure 2 This is a front cross-sectional view of the metal joint body structure of the utility model;

[0020] Figure 3 This is a three-dimensional cross-sectional view of the metal dissimilar joint structure of the utility model;

[0021] Figure 4 This is a three-dimensional exploded cross-sectional view showing two types of metal joints of the utility model;

[0022] Figure 5 It is a three-dimensional schematic diagram of another metal joint body structure of the utility model.

[0023] In the figure: metal joint body 1, hole 2, connecting hole 3, internal thread 4, metal round cap 5, metal heterogeneous joint 6, injection hole A 7, injection hole B 8, injection groove 9. DETAILED DESCRIPTION

[0024] The following will be combined with the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0025] See also Figure 1-Figure 5 ;

[0026] Embodiment 1:

[0027] A high-pressure sealing cover for a hydrogen cylinder interface, comprising a metal joint body 1 and a plastic upper tank body formed by injection molding, wherein a hole 2 is vertically opened on the bottom end surface of the metal joint body 1;

[0028] The holes 2 are arranged in two groups, inside and outside, and each group of holes 2 is evenly arranged in a circle on the bottom surface of the metal joint body 1;

[0029] Two groups of connecting holes 3 are horizontally opened in the bottom of the metal joint body 1, and the connecting holes 3 are evenly distributed along the radial direction of the metal joint body 1. The connecting holes 3 connect the corresponding inner and outer groups of holes 2. The inner wall of the top of the metal joint body 1 is provided with an internal thread 4;

[0030] Two groups of injection holes A7 are evenly opened on the outer side of the bottom end of the metal joint body 1 at positions corresponding to the connection holes 3 , and the two groups of injection holes A7 are connected to the inside of the corresponding connection holes 3 respectively.

[0031] Embodiment 2:

[0032] A high-pressure sealing cover for a hydrogen cylinder interface, comprising a metal joint body 1 and a plastic upper tank body formed by injection molding, wherein a hole 2 is vertically opened on the bottom end surface of the metal joint body 1;

[0033] The holes 2 are arranged in two groups, inside and outside, and each group of holes 2 is evenly arranged in a circle on the bottom surface of the metal joint body 1;

[0034] Two groups of connecting holes 3 are horizontally opened in the bottom of the metal joint body 1, and the connecting holes 3 are evenly distributed along the radial direction of the metal joint body 1. The connecting holes 3 connect the corresponding inner and outer groups of holes 2. The inner wall of the top of the metal joint body 1 is provided with an internal thread 4;

[0035] Two groups of injection holes B8 are evenly arranged on the outer side of the bottom end of the metal joint body 1 at positions corresponding to the connecting holes 3. The two groups of injection holes B8 are respectively connected to the inside of the corresponding connecting holes 3. Two injection grooves 9 connected end to end are arranged on the outer side of the bottom end of the metal joint body 1 at positions corresponding to the two groups of injection holes B8. The inside of each injection groove 9 is connected to the corresponding injection hole B8.

[0036] Embodiment three:

[0037] A high-pressure sealing cover for a hydrogen cylinder interface, comprising a metal joint body 1 and a plastic upper tank body formed by injection molding, wherein a hole 2 is vertically opened on the bottom end surface of the metal joint body 1;

[0038] The holes 2 are arranged in two groups, inside and outside, and each group of holes 2 is evenly arranged in a circle on the bottom surface of the metal joint body 1;

[0039] Two groups of connecting holes 3 are horizontally opened in the bottom of the metal joint body 1, and the connecting holes 3 are evenly distributed along the radial direction of the metal joint body 1. The connecting holes 3 connect the corresponding inner and outer groups of holes 2. The inner wall of the top of the metal joint body 1 is provided with an internal thread 4;

[0040] Two groups of injection holes A7 are evenly opened on the outer side of the bottom end of the metal joint body 1 at positions corresponding to the connection holes 3, and the two groups of injection holes A7 are respectively connected to the inside of the corresponding connection holes 3;

[0041] A metal round cap 5 is arranged below the metal joint body 1 , and the top end surface of the metal round cap 5 is welded to the bottom end surface of the metal joint body 1 , and the metal round cap 5 and the metal joint body 1 form a metal dissimilar joint 6 .

[0042] Embodiment 4:

[0043] A high-pressure sealing cover for a hydrogen cylinder interface, comprising a metal joint body 1 and a plastic upper tank body formed by injection molding, wherein a hole 2 is vertically opened on the bottom end surface of the metal joint body 1;

[0044] The holes 2 are arranged in two groups, inside and outside, and each group of holes 2 is evenly arranged in a circle on the bottom surface of the metal joint body 1;

[0045] Two groups of connecting holes 3 are horizontally opened in the bottom of the metal joint body 1, and the connecting holes 3 are evenly distributed along the radial direction of the metal joint body 1. The connecting holes 3 connect the corresponding inner and outer groups of holes 2. The inner wall of the top of the metal joint body 1 is provided with an internal thread 4;

[0046] Two groups of injection holes B8 are evenly arranged on the outer side of the bottom end of the metal joint body 1 at positions corresponding to the connection holes 3, and the two groups of injection holes B8 are respectively connected to the inside of the corresponding connection holes 3. Two injection grooves 9 connected end to end are arranged on the outer side of the bottom end of the metal joint body 1 at positions corresponding to the two groups of injection holes B8, and the inside of each injection groove 9 is connected to the corresponding injection hole B8;

[0047] A metal round cap 5 is arranged below the metal joint body 1 , and the top end surface of the metal round cap 5 is welded to the bottom end surface of the metal joint body 1 , and the metal round cap 5 and the metal joint body 1 form a metal dissimilar joint 6 .

[0048] The beneficial effects of the utility model are as follows: the hydrogen cylinder interface is provided with a high-pressure sealing cover, and a hole is designed on the metal joint. When the tank temperature rises, thermal expansion occurs. The expansion of metal is much smaller than that of plastic, which normally causes a gap between plastic and metal. However, the patent uses the hole inside the metal joint to offset the opposite effects of the different thermal expansion degrees of the plastic and metal joints. At the same time, not only will no gap appear, but the joints will be squeezed tighter. On the contrary, the same principle applies when the tank contracts due to cold. The plastic shrinks more and the metal joint will be wrapped. Tighter, solving the problem of high-pressure hydrogen leakage caused by thermal expansion and contraction; at the same time, since this structure does not use threads or rely on external force to squeeze each other to seal, it ensures the service life of plastic and metal, and is not prone to metal fatigue and plastic aging. Through mechanical high-pressure extrusion of engineering plastics, it ensures that the plastic can fill any cavity in the mold, and since the injected plastic is squeezed in with high pressure, it ensures that the plastic in the cavity is firm and full, so that when the plastic enters the hole of the metal joint, it will form a large combination extrusion force in the metal hole, eliminating the leakage.

[0049] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high-pressure sealing cover for the interface of a hydrogen cylinder, comprising a metal joint body (1) and a plastic upper tank body integrally formed by injection molding, characterized in that: The bottom end surface of the metal joint body (1) is provided with a hole (2) extending vertically upward; The holes (2) are arranged in two groups, one inside the other, and each group of holes (2) is evenly arranged in a circle on the bottom surface of the metal joint body (1); Two groups of connection holes (3) are horizontally opened in the bottom of the metal joint body (1), and the connection holes (3) are evenly distributed along the radial direction of the metal joint body (1). The connection holes (3) connect the corresponding inner and outer groups of holes (2).

2. A high-pressure sealing cover for a hydrogen cylinder interface according to claim 1, characterized in that: An internal thread (4) is formed on the inner wall of the top end of the metal joint body (1).

3. The high-pressure sealing cover for the interface of a hydrogen cylinder according to claim 1, characterized in that: A metal round cap (5) is arranged below the metal joint body (1); the top end surface of the metal round cap (5) is welded to the bottom end surface of the metal joint body (1); the metal round cap (5) and the metal joint body (1) form a metal dissimilar joint (6).

4. The high-pressure sealing cover for the interface of a hydrogen cylinder according to claim 1, characterized in that: Two groups of injection holes A (7) are evenly arranged on the outer side of the bottom end of the metal joint body (1) at positions corresponding to the connection holes (3), and the two groups of injection holes A (7) are respectively connected to the inside of the corresponding connection holes (3).

5. The high-pressure sealing cover for the interface of a hydrogen cylinder according to claim 1, characterized in that: Two groups of injection holes B (8) are evenly arranged on the outer side of the bottom end of the metal joint body (1) at positions corresponding to the connection holes (3), and the two groups of injection holes B (8) are respectively connected to the inside of the corresponding connection holes (3). Two injection grooves (9) connected end to end are arranged on the outer side of the bottom end of the metal joint body (1) at positions corresponding to the two groups of injection holes B (8), and the inside of each injection groove (9) is connected to the corresponding injection hole B (8).

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