Type IV assembled hydrogen storage cylinder liner and assembly method

Abstract

The present invention discloses a plastic liner of a type IV hydrogen storage cylinder and an assembly method. The liner includes a front and rear head assembly and a barrel section structure. The head assembly is respectively arranged at both ends of the barrel section structure. The head assembly includes an external joint, a radial sealing ring, an end face sealing ring and a joint insert. The external joint is assembled at the corresponding thread position of the joint insert. The joint insert structure is optimized for the head assembly, the external joint torque conversion tooling and the joint insert torque conversion tooling are supplemented, the end face sealing ring and the radial sealing ring are installed, silicone rubber is applied to the inclined surface of the external joint, the external joint torque conversion tooling is installed using a torque wrench, the joint insert is fixed using the joint insert torque conversion tooling, the torque is loaded, and after completion, the assembly gap is coated with silicone rubber, thereby realizing the assembly of the plastic liner of the type IV hydrogen storage cylinder. The present invention adopts a torque wrench, the assembly torque can be measured, and the assembly torque design requirements can be met; the compression amount of the end face and the radial sealing ring is ensured to meet the high-pressure sealing requirements.

Description

Technical Field

[0001] The invention relates to the field of preparation and molding of gaseous high-pressure hydrogen storage cylinders, and in particular to an IV-type assembled hydrogen storage cylinder liner and an assembly method. Background Art

[0002] At present, 70MPa aluminum alloy liner type III carbon fiber fully wrapped hydrogen storage cylinders have been developed, but this type of cylinder has low hydrogen storage density and high manufacturing cost, which seriously hinders its mass application in new energy fuel cell vehicles. In order to achieve higher hydrogen storage density, specific strength and long life, the development of a new generation of lightweight and low-cost 70MPa type IV plastic liner carbon fiber fully wrapped hydrogen storage cylinders is the main development direction in the field of gaseous high-pressure hydrogen storage cylinders. The main technical difficulty of 70MPa high-pressure type IV hydrogen storage cylinders is to solve the hydrogen leakage problem caused by the failure of the bottle mouth sealing structure of the plastic liner of the gas cylinder under 70MPa high-pressure working conditions due to the high-pressure load.

[0003] The structure of the plastic liner of the assembled hydrogen storage cylinder is as follows: Figure 1 As shown, the structure has front and rear external joints and a plastic inner liner. At present, the structure is often installed on the square structure of the front and rear external joints using a pipe clamp, and two people are required to clamp the pipe clamp to the installation position. The assembly torque of this method cannot be measured, whether the installation is in place cannot be satisfied, the compression of the sealing ring cannot be guaranteed, and the front and rear joints need to have positions for the pipe clamp installation wrench, which increases the weight of the front and rear joints. This patent is aimed at the assembly process of the plastic liner of a Type IV hydrogen storage cylinder, and based on the above problems, a Type IV assembled hydrogen storage cylinder liner assembly method is designed.

[0004] The current method for assembling the plastic liner of a Type IV hydrogen storage cylinder with a working pressure of 70 MPa has the following disadvantages:

[0005] 1) The assembly torque cannot be measured and the assembly quality cannot be controlled;

[0006] 2) The assembly position cannot be guaranteed and the compression amount of the sealing ring cannot be guaranteed;

[0007] 3) The clamping of the pipe will cause a certain torque on the plastic liner, which will damage the liner.

[0008] In view of these shortcomings, a method for assembling the plastic liner of Type IV hydrogen storage cylinders was designed. The method is used for the assembly and molding of the plastic liner of Type IV hydrogen storage cylinders with a working pressure of 70 MPa. In order to solve the problem of controllable assembly torque and reliable compression of the sealing ring, the assembly sealing of the plastic liner under high pressure load is ensured. Summary of the invention

[0009] Technical Problems to be Solved by the Invention

[0010] The present invention provides an assembly method for an inner liner of an IV-type assembled hydrogen storage gas cylinder, so as to solve the problems that the inner liner of an existing hydrogen storage gas cylinder liner assembly method is damaged and the compression amount of a sealing ring cannot be guaranteed.

[0011] To solve the technical problem, the present invention adopts the technical solution

[0012] A plastic liner of a type IV hydrogen storage cylinder is composed of a front head assembly 1, a barrel section structure 2 and a rear head assembly 3. The front head assembly 1 and the rear head assembly 3 are respectively arranged at both ends of the barrel section structure. The front head assembly and the rear head assembly have the same structure. The front head assembly is composed of an external joint 4, a radial sealing ring 5, an end face sealing ring 6 and a joint insert 7. The external joint 4 is precisely assembled in the corresponding thread position of the joint insert 7, which ensures that the radial sealing ring 5 and the end face sealing ring 6 have reliable compression and also ensures that the assembly bevels of the front and rear external joints 4 and the bevels of the plastic liner are matched without clearance.

[0013] Furthermore, the joint insert 7 is made of S31603 stainless steel, with a tensile strength greater than 488 MPa and a Brinell hardness greater than 185.

[0014] Furthermore, three evenly distributed holes are additionally milled on the inner cylindrical surface of the joint insert 7 to fix three evenly distributed bosses in the torque conversion tooling 10 of the front and rear joint inserts.

[0015] Furthermore, one end of the joint insert torque conversion tooling 10 is evenly designed with three evenly distributed bosses, the size of which matches the three evenly distributed holes of the joint insert 7, and the other end is processed into a square, which is convenient for using a pipe clamp 9 to fix the joint insert torque conversion tooling 10.

[0016] A method for assembling a plastic liner of a type IV hydrogen storage cylinder, with specific steps:

[0017] S1: Use alcohol to wipe the front and rear external joints 4 of the gas cylinder, the assembly surface and sealing surface of the plastic liner, test the front and rear external joints 4, and measure whether the installation is in place, whether the sealing ring is compressed, and whether the size of the assembly surface gap is reasonable. If the requirements are met, proceed to the next step. If not, repair the assembly surface;

[0018] S2: Wipe the lubricant to fix the end face seal ring and radial seal ring, apply silicone rubber evenly on the assembly surface, and apply Loctite 243 thread fastener (Q / LCT001) evenly on the threaded mating parts of the front and rear external joints 4 and the front and rear joint inserts 7;

[0019] S3: Use torque wrench 8 to install front and rear external joint torque conversion tooling 11, and then use pipe clamp 9 and front and rear joint insert torque conversion tooling 10 to fix front and rear joint inserts 7, load the design torque of 500N.m, and then use silicone rubber to coat the assembly gap after completion, so as to realize the assembly of plastic liner of Type IV hydrogen storage cylinder.

[0020] Furthermore, the external joint torque conversion tooling 11 of S3 processes two squares, the large square is used to fix the small end squares of the front and rear external joints 4, and the small square is used to fix the small square of the torque wrench, the material is 45#, and the heat treatment is HRC23-28.

[0021] Technical effects obtained by the present invention

[0022] The present invention adopts a torque wrench, and the assembly torque can be measured, which can meet the assembly torque design requirements; the compression amount of the end face and the radial sealing ring is ensured to meet the high-pressure sealing requirements; the present invention adopts silicone rubber to fill the gap of the assembly bevel. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 : Schematic diagram of the plastic liner structure of a 70MPa type IV assembled hydrogen storage cylinder;

[0024] Figure 2 : Schematic diagram of the front and rear end caps of the plastic liner of a 70MPa type IV assembled hydrogen storage cylinder;

[0025] Figure 3 : Plastic assembly method for type IV assembled hydrogen storage cylinders at 70MPa;

[0026] Figure 4 : Schematic diagram of the improved structure of the connector insert;

[0027] Figure 5 : Schematic diagram of external joint structure;

[0028] Figure 6 : Schematic diagram of the external joint torque conversion tooling structure;

[0029] Figure 7 : Schematic diagram of the torque conversion tooling structure of the joint insert;

[0030] Among them: 1-front head assembly, 2-barrel section structure, 3-rear head assembly, 4-external joint, 5-radial sealing ring, 6-end face sealing ring, 7-joint insert, 8-torque wrench, 9-pipe clamp, 10-joint insert torque conversion tooling, 11-external joint torque conversion tooling, 12-70MPa Type IV assembled hydrogen storage cylinder plastic liner front and rear head bottle mouth. DETAILED DESCRIPTION

[0031] This patented invention designs a method for assembling the plastic liner of a Type IV hydrogen storage cylinder. Figure 1The plastic liner structure of the 70MPa type IV assembled hydrogen storage cylinder shown in the figure optimizes and improves the structure of the front and rear joint embedded parts 7 for the front head assembly 1, supplements the processing of the front and rear external joint torque conversion tooling 11 and the front and rear joint embedded parts torque conversion tooling 10, installs the end face sealing rings and radial sealing rings, evenly applies silicone rubber to the inclined surfaces of the front and rear external joints, uses a torque wrench to install the front and rear external joint torque conversion tooling, and then uses the front and rear joint embedded parts torque conversion tooling to fix the front and rear joint embedded parts 7, loads the design torque of 500N.m, and after completion, uses silicone rubber to apply the assembly gap, thereby realizing the assembly of the plastic liner of the type IV hydrogen storage cylinder.

[0032] In order to make the purpose, features and advantages of the technical solution proposed in the present invention more obvious and easy to understand, the embodiments of the technical solution proposed in the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the proposed technical solution, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0033] The patent of this invention designs a method for assembling the plastic liner of a Type IV hydrogen storage cylinder, which avoids the liner from being subjected to large torque during the assembly process, ensures the compression of the sealing ring, and ensures the sealing performance of the plastic liner under high pressure load. Figure 1 As shown in the figure, the structure of the plastic liner of the Type IV gas cylinder is mainly composed of the front head assembly 1, the barrel structure 2 and the rear head assembly 3, and the sealing structure of the plastic liner of the Type IV gas cylinder is located at the front head assembly 1 and the rear head assembly 3, and the sealing performance of these two places is very important under high pressure load conditions. Figure 2 The figure shows the front and rear end caps of the plastic liner of a 70MPa type IV assembled hydrogen storage cylinder. The end cap assembly consists of an external joint 4, a radial sealing ring 5, an end face sealing ring 6 and a joint insert 7. The external joint 4 is precisely assembled in the corresponding thread position of the joint insert 7, which ensures that the radial sealing ring 5 and the end face sealing ring 6 have reliable compression and that the assembly bevel of the external joint 4 and the bevel of the plastic liner fit without clearance.

[0034] According to the above assembly relationship, the structure of the joint insert 7 is optimized and improved. The specific structure is shown in Figure 4 The material of the joint insert 7 is S31603 stainless steel, with a tensile strength greater than 488MPa and a Brinell hardness greater than 185. Three evenly distributed holes are milled on its inner cylindrical surface, with a height of 2mm and a width of 5mm, to fix the three evenly distributed bosses in the joint insert torque conversion fixture 10. The evenly distributed holes are not located on the sealing surface and require process root cleaning. In addition, the structure of the joint insert torque conversion fixture 10 is shown in FIG. Figure 7As shown, three evenly distributed bosses are evenly designed, and their sizes match the three evenly distributed holes of the joint insert 7, with a height of 1.9mm, a width of 4.9mm, a material of 45#, and a heat treatment of HRC23-28. A square is processed at the other end to facilitate the use of a pipe clamp 9 to fix the torque conversion tooling 10 of the joint insert.

[0035] In order to facilitate the controllable assembly torque, an external joint torque conversion tool 11 is added. The specific structure is shown in Figure 6 The tooling processes two squares. The large square is used to fix the 4 small end squares of the external joint, and the small square is used to fix the small square of the torque wrench. The material is 45# and the heat treatment is HRC23-28.

[0036] 70MPa Type IV assembled hydrogen storage cylinder plastic assembly method, such as Figure 3 As shown, during the liner assembly process, first use alcohol to wipe the front and rear external joints 4 of the gas cylinder, the assembly surface and sealing surface of the plastic liner, test the front and rear external joints 4, measure whether the installation is in place, whether the sealing ring is compressed, and whether the size of the assembly surface gap is reasonable. If it meets the requirements, proceed to the next step. If it does not meet the requirements, repair the assembly surface. Then, wipe the lubricant to fix the end face sealing ring and radial sealing ring, evenly apply silicone rubber to the assembly surface, and evenly apply Loctite 243 thread fastener (Q / LCT 001) to the threaded mating parts of the front and rear external joints 4 and the front and rear joint inserts 7. Finally, use the torque wrench 8 to install the torque conversion tooling of the front and rear external joints, and then use the pipe clamp 9 and the front and rear joint insert torque conversion tooling 10 to fix the front and rear joint inserts 7, load the design torque of 500N.m, and then use silicone rubber to apply the assembly gap after completion, so as to realize the assembly of the plastic liner of the type IV hydrogen storage gas cylinder.

[0037] The plastic liner assembled by this method has been tested by flaw detection. The compression rate of the end face sealing ring is 25%, the compression rate of the radial sealing ring is 20%, the winding molded gas cylinder has good sealing performance and passed the 196.7MPa water pressure test.

Claims

1. A plastic liner of a type IV hydrogen storage cylinder, characterized in that: The invention is composed of a front end head assembly (1), a barrel section structure (2) and a rear end head assembly (3). The front end head assembly (1) and the rear end head assembly (3) are respectively arranged at two ends of the barrel section structure. The front end head assembly and the rear end head assembly have the same structure. The front end head assembly is composed of an external joint (4), a radial sealing ring (5), an end face sealing ring (6) and a joint insert (7). The external joint (4) is precisely assembled on the corresponding thread position of the joint insert (7), which ensures that the radial sealing ring (5) and the end face sealing ring (6) have reliable compression and also ensures that the assembly inclined surfaces of the front and rear external joints (4) and the inclined surfaces of the plastic liner are matched without clearance. The inner cylindrical surface of the joint insert (7) is additionally milled with three evenly distributed holes for fixing three evenly distributed bosses in the torque conversion tooling (10) of the front and rear joint inserts.

2. A plastic liner of a type IV hydrogen storage cylinder according to claim 1, characterized in that: The joint insert (7) is made of S31603 stainless steel, with a tensile strength greater than 488 MPa and a Brinell hardness greater than 185.

3. A plastic liner of a type IV hydrogen storage cylinder according to claim 1, characterized in that: One end of the joint insert torque conversion tooling (10) is evenly designed with three evenly distributed bosses, the size of which matches the three evenly distributed holes of the joint insert (7), and the other end is processed into a square, so as to facilitate the use of a pipe clamp (9) to fix the joint insert torque conversion tooling (10).

4. A method for assembling a plastic liner of a type IV hydrogen storage cylinder, characterized in that: Specific steps: S1: Use alcohol to wipe the front and rear external joints (4) of the gas cylinder, the assembly surface and the sealing surface of the plastic liner, test the front and rear external joints (4), and measure whether the installation is in place, whether the sealing ring is compressed, and whether the size of the assembly surface gap is reasonable. If the requirements are met, proceed to the next step. If the requirements are not met, repair the assembly surface; S2: Wipe the lubricant and fix the end face sealing ring and radial sealing ring, evenly apply silicone rubber to the assembly surface, and evenly apply Loctite 243 thread fastener to the threaded mating parts of the front and rear external joints (4) and the front and rear joint inserts (7); S3: Use a torque wrench (8) to install the front and rear external joint torque conversion tooling (11), then use a pipe clamp (9) and the front and rear joint insert torque conversion tooling (10) to fix the front and rear joint inserts (7), load the design torque of 500N.m, and then use silicone rubber to smear the assembly gap after completion, so as to realize the assembly of the plastic liner of the IV type hydrogen storage cylinder.

5. A method for assembling a plastic liner of a type IV hydrogen storage cylinder according to claim 4, characterized in that: The S3 external joint torque conversion tooling (11) is processed with two squares, the large square is used to fix the small end squares of the front and rear external joints (4), and the small square is used to fix the small square of the torque wrench. The material is 45# and the heat treatment is HRC23-28.

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