JP5255586B2 - High pressure vessel seal structure and seal member used therefor - Google Patents

Description

  The present invention relates to a seal structure for sealing between a high-pressure container filled with a fluid at high pressure and an accessory such as a connecting pipe and a stopcock adjacent to the high-pressure container, and more specifically, a seal member used for the seal structure. The present invention relates to a seal structure capable of suppressing leakage of fluid from between a high-pressure container and a joining member when a high-pressure container is used for filling and discharging an ultra-high pressure fluid, and a seal member used therefor.

  The high-pressure vessel is mainly used for storing fluids such as hydrogen, oxygen, and nitrogen, and these fluids are filled at a high pressure. When a high-pressure container is used for filling and discharging a high-pressure fluid, accessories such as a connecting pipe to which a pipe can be attached and a stopper for sealing an opening are adjacent to each other. In order to prevent the high-pressure fluid that is filled and discharged from leaking between the high-pressure vessel and the accessory, a seal member is disposed between the high-pressure vessel and the accessory. Conventionally, the maximum pressure of the fluid to be filled and discharged has been 20 MPa.

  In recent years, development of fuel cell vehicles has been rapidly advanced, and hydrogen gas is used as the fuel. In a fuel cell vehicle, hydrogen gas stored in a high pressure vessel of a hydrogen station is used by filling a gas tank provided in the fuel cell vehicle. In order to improve the filling capacity of the gas tank, in a fuel cell vehicle, hydrogen gas may be filled into the gas tank at a pressure of 35 MPa or more, further 90 MPa or more, exceeding 20 MPa which is conventionally used. For this reason, the high-pressure vessel in which the gas tank is filled with hydrogen gas and the seal structure used therefor are also required to have no leakage at a pressure of 35 MPa or more, and further, a pressure of 90 MPa or more.

  FIG. 1 is a cross-sectional view showing a seal structure used in a conventional high-pressure vessel. The seal structure shown in the figure shows a case where a connection pipe is used as an accessory, and a high-pressure container 1 for filling and discharging a high-pressure fluid, a connection pipe 2 adjacent to the high-pressure container, and a fluid for preventing leakage. An O-ring 3 that is a sealing member and a cap nut 4 that fixes an accessory (connection pipe 2) adjacent to the high-pressure vessel 1 are used.

  The high-pressure container 1 includes a container part 1a filled with fluid, an opening part 1b serving as a fluid flow path, a screw part 1c to which a cap nut is tightened, and a joint surface 1d that joins an adjacent accessory. ing. The connecting pipe 2 includes a groove 2a for receiving an O-ring serving as a seal member on a joint surface 1d with the high-pressure vessel, and an opening 2b serving as a fluid flow path. The cap nut 4 is connected to the high-pressure vessel and an accessory (connection) A leak port 4a which is a hole for detecting a fluid leak at the joint surface of the tube 2) is provided.

  As shown in the figure, in the seal structure, a seal member is arranged between the high-pressure vessel 1 and the accessory (connection pipe 2) by embedding an O-ring 3 in the groove 2a of the accessory (connection pipe 2). . In this state, the cap nut 4 is tightened, and the accessory (connection pipe 2) is pressed against the high-pressure vessel 1, whereby the O-ring 3 is compressed and deformed, and the joining surface 1d of the high-pressure vessel and the groove portion 2a of the accessory (connection tube 2). Close contact with the bottom of the.

  Further, when the high pressure fluid is filled and discharged, the O-ring is deformed in the diameter expansion direction by the pressure of the high-pressure fluid, and the O-ring and the outer peripheral side surface of the groove portion of the accessory are in close contact with each other. In this way, the joint surface of the O-ring and the high-pressure vessel, the bottom surface of the groove portion of the accessory and the side surface on the outer peripheral side are in close contact with each other to improve airtightness and prevent fluid from leaking between the high-pressure vessel and the accessory. Yes. Hereinafter, the portion where the seal member (O-ring), the high-pressure vessel and the accessories (connection pipe and stopper) are in close contact with each other is also referred to as a seal portion.

  In general, in a seal structure, a seal member is compressed and deformed to be in close contact with a high-pressure vessel and accessories. At this time, it is known that the pressure generated between the compression-deformed seal member and the high-pressure vessel and accessories is the maximum pressure of the fluid that can be hermetically sealed. That is, the pressure generated when the sealing member, the high-pressure vessel and the accessories are in close contact with each other needs to be equal to or higher than the pressure of the fluid to be filled / released. In the seal structure shown in the figure, the pressure generated in the seal portion is adjusted by the torque when tightening the cap nut.

  When using a high-pressure vessel for filling and discharging high-pressure gas, it is necessary to conduct an air-tight test at a pressure higher than the design pressure in order to check the air-tightness by the high-pressure gas safety method. After adjusting the tightening torque of the cap nut using the seal structure shown in FIG. 1, when the high pressure container is filled or discharged with a fluid having a pressure exceeding 35 MPa, the high pressure container and its accessories (connecting pipes and stoppers) In some cases, fluid leaks from the gap. In this case, the product yield decreases due to the cost required for the hermetic test and the rework when the hermetic test fails.

  In addition, when a rubber material is used as a seal member when filling or releasing a fluid having a pressure exceeding 20 MPa by the seal structure shown in FIG. 1, the seal member is embedded due to the differential pressure between the external pressure and the fluid to be filled / released. There is a possibility that the sealing member is detached from the groove and the airtightness is lowered.

  Conventionally, various proposals have been made as a seal structure that can be used for filling and discharging a fluid having a pressure exceeding 20 MPa.

  Patent Document 1 proposes a seal structure used for a shutoff valve in a high-pressure container of fiber-reinforced plastic filled with high-pressure hydrogen gas such as 35 MPa or 70 MPa. In Patent Document 1, the seal member for partitioning the space is made of an elastic body such as a rubber material. The annular portion formed on the high-pressure first space side is smaller in volume than the first annular portion. A seal structure using an annular portion formed on the space side has been proposed.

  In the seal structure proposed in Patent Document 1, when the valve is closed by bringing the seal member into contact with the valve seat by making the volume of the second annular portion smaller than that of the first annular portion, The elastic body flows from the first annular portion toward the second annular portion on the low pressure side, the seal pressure due to the contact between the elastic body and the valve seat is increased in the second annular portion, and fluid leakage can be prevented. It is said. Further, when the elastic body flows, the surplus volume integral arranged in the first annular portion moves to the second annular portion, so that the distortion of the entire sealing member is alleviated and no large deformation occurs, and the sealing member Can be prevented from coming off the groove.

  In the seal structure proposed in Patent Document 1, an elastic body such as a rubber material is used as the seal member. When a rubber material is exposed in a high-pressure gas environment, so-called blister breakdown may occur, in which bubbles or cracks are generated from the inside of the rubber after decompression. Therefore, in the seal structure proposed in Patent Document 1, there is a high risk that blister breakage will occur in the seal member by repeatedly filling and releasing the high-pressure gas into the high-pressure vessel, and durability is a problem.

JP 2009-133497 A

  As described above, the seal structure used in the conventional high-pressure vessel is over 20 MPa, when the fluid is filled at a pressure of 35 MPa or more, and further, a pressure of 90 MPa or more, the occurrence of leakage or the blister breakdown that occurs in a high-pressure gas environment Durability due to is a problem.

  The present invention has been made in view of such a situation. Even when a high-pressure vessel is filled with a fluid at a pressure of 35 MPa or more, and further, a pressure of 90 MPa or more, airtightness can be secured, and blister breakage can be prevented and durability can be secured. It aims at providing the sealing structure excellent in property, and the sealing member used for it.

  As a seal structure that can ensure airtightness even when a high-pressure vessel is filled with a fluid at a pressure of 35 MPa or higher, or a pressure of 90 MPa or higher, in the seal structure shown in FIG. We investigated the use of an octagonal ring joint gasket with an octagonal cross-section. When an octagonal ring joint gasket is used, sufficient airtightness can be ensured without causing leakage when filling and discharging a high-pressure fluid up to 50 MPa.

  However, in filling and discharging a high-pressure fluid exceeding 50 MPa, a pressure necessary for ensuring airtightness is generated in the seal portion, which increases the torque for tightening the cap nut. For example, when the thread size is M60 and the design pressure is 90 MPa, the tightening torque is 200 kgf · m, which is not practical in terms of work when the operator attaches alone. For this reason, it turned out that it is difficult to use an octagonal type ring joint gasket for the sealing member of the high pressure fluid of 50 Mpa or more.

  The inventor further conducted various tests, and as a result of intensive studies, the seal member and the high-pressure vessel, and the seal member and the accessory seal part were each fitted with a taper to 90 MPa or more. It was found that airtightness can be secured even when a high pressure vessel is filled with a fluid at a pressure of 5 μm.

  The present invention has been completed on the basis of the above findings, and the gist of the sealing structure of the high-pressure vessel (1) and (2) below and the sealing member of the high-pressure vessel (3) and (4) below.

(1) A sealing structure that seals between an end face of a high-pressure vessel and an end face of an accessory by disposing a seal member between the high-pressure vessel and an accessory adjacent thereto, and the cylindrical sealing member but has a first tapered surface and the second tapered surface on the outer periphery, has a hole through which fluid flows to the axis, the first tapered surface, Ri diameter is smaller as the distance from the second tapered surface, the diametrically contracted the first tapered surface is formed on one end face and communicating a so that the seal member, the second tapered surface, said Ri diameter is smaller as the first distance from the tapered surface, the second tapered surface of the reduced diameter is formed on the other end face and communicating a so that the seal member, becomes the first tapered surface is said high pressure vessel is I because fitting engagement in a tapered surface provided in the opening of the sealing surface, the first second tapered surface Sealing structure for a high-pressure container whose serial is I because fitting engagement in a tapered surface provided in the opening or recess of the accessory and is characterized in that the sealing surface.

(2) The sealing structure for a high-pressure vessel according to (1), wherein the sealing member is made of a metal material.

(3) a cylindrical sealing member for sealing between the end face of the high-pressure vessel with the end face of the accessory by being disposed between the accessory adjacent to the high-pressure container and which, the high-pressure vessel The outer periphery of the first tapered surface that is fitted with the tapered surface provided in the opening portion of the opening and becomes the sealing surface and the second tapered surface that is fitted with the tapered surface provided in the opening portion or the recessed portion of the accessory and becomes the sealing surface and having a, has a hole through which fluid flows to the axis, the first tapered surface, the diameter is reduced as the second distance from the tapered surface, diametrically contracted in the first tapered surface is one end surface and communicating is formed in such so that, the second tapered surface, the diameter is reduced as the distance from the first tapered surface, the diametrically contracted in the second tapered surface is formed on the other end face and communicating a so that Special High-pressure vessel seal member to.

(4) The sealing member for a high-pressure vessel according to (3), wherein the sealing member is made of a metal material.

  According to the seal structure of the high-pressure vessel of the present invention, the seal member and the high-pressure vessel, and the seal portion of the seal member and the accessory are fitted to each other using a taper, so that the pressure is 35 MPa or more, and further 90 MPa or more. Even when the fluid is filled / discharged at a pressure of 1, it is possible to ensure airtightness without causing leakage. Furthermore, by using stainless steel with a JIS symbol SUS316L as the seal member, blister destruction that is a concern with seal members using resin materials, rubber materials, etc., and hydrogen embrittlement that is a concern with seal members using metal materials, etc. Can be prevented, and excellent durability can be ensured even in a hydrogen environment.

  The seal member of the high-pressure vessel of the present invention used for this seal structure has a first taper surface and a second taper surface fitted to the high-pressure vessel and the accessory, so that the seal member and the high-pressure vessel, and the seal member and the accessory Each of the seal portions can be fitted using a taper, and even when used in a seal structure that fills and discharges fluid at a pressure of 35 MPa or more, and further a pressure of 90 MPa or more, no leakage occurs. Airtightness can be ensured.

It is sectional drawing which shows the seal structure used for the conventional high pressure vessel. FIG. 3 is a cross-sectional view illustrating a configuration example in the case of using a connecting pipe as an accessory, which is a high-pressure container sealing structure of the present invention. FIG. 2 is a cross-sectional view illustrating an example of a configuration in the case of using a stopper as an accessory, which is a high-pressure container seal structure of the present invention. It is a high-pressure container seal structure of the present invention, and is a sectional view explaining the case where a seal part is stuck by a flange type. It is a figure which shows the relationship between the fluid pressure with which it filled in the airtight test using the seal structure of the example of this invention, or a comparative example, and a leak generation rate (%).

  Below, the sealing structure of the high-pressure vessel of this invention and the sealing member used therewith are demonstrated based on drawing.

  FIG. 2 is a cross-sectional view illustrating an example of the configuration in the case of using a connecting pipe as an accessory, which is a high-pressure container sealing structure according to the present invention. In the seal structure shown in the figure, the fluid leaks from the high-pressure vessel 1 that fills and discharges the high-pressure fluid, the connecting pipe 2 that is an accessory adjacent to the high-pressure vessel, and between the high-pressure vessel 1 and the connecting pipe 2. A seal member 5 to be prevented and a cap nut 4 for fixing the connecting pipe 2 to the high-pressure vessel 1 are used.

The sealing structure of the high-pressure vessel according to the present invention is such that the seal member 5 is disposed between the high-pressure vessel 1 and the accessory (connection pipe 2) adjacent thereto, thereby providing an end face of the high-pressure vessel 1 and the accessory (connection tube 2). The cylindrical sealing member 5 has a first taper surface 5a and a second taper surface 5b on the outer periphery, and has a hole through which fluid flows in the shaft center. the first tapered surface 5a is Ri a diameter smaller as the distance from the second tapered surface 5b, reduced diameter side of the first tapered surface 5a is formed on one end surface and communicating a so that the seal member, a second tapered surface 5b is Ri diameter is smaller as the distance from the first tapered surface 5a, reduced diameter side of the second tapered surface 5b is formed on the other end face and communicating a so that the seal member, a first tapered surface 5a is high Installed in the opening 1b of the container Was become being I if fitted to the tapered surface 1e sealing surface, the second tapered surface 5b to become accessories (connecting pipe 2) is I if a seal surface fitted to the tapered surface 2c which is provided in the opening 2b of the It is characterized by.

  That is, the first taper surface 5a formed so that the diameter decreases as it goes away from the second taper surface 5b is provided on the outer periphery of the seal member 5, and the taper surface 1e is provided in the opening 1b of the high-pressure vessel 1 to seal the seal. The seal part of the member 5 and the high-pressure vessel 1 is fitted with a taper. In addition, a second tapered surface 5b is formed on the outer periphery of the seal member 5 so that the diameter decreases as the distance from the first tapered surface 5a increases, and a tapered surface 2c is provided in the opening 2b of the connecting pipe 2 to seal the seal member 5 The seal part of the member 5 and the connecting pipe 2 is fitted with a taper.

  In this way, the seal member and the high-pressure vessel, and the seal portion of the seal member and the accessory are fitted with each other using a taper, so that the seal portion is strongly adhered and the airtightness is improved. Even if the torque during tightening is within a practical range, a pressure of 90 MPa or more can be generated in the seal portion.

  For example, when the thread size of the high-pressure vessel is M60 and the design pressure is 90 MPa, the tightening torque of the cap nut is 200 kgf · m in the seal structure using the aforementioned octagonal ring joint gasket, In the high-pressure container seal structure of the present invention, the pressure is 110 kgf · m. This is because the seal member can be arranged at a distance closer to the fluid flow path than the conventional seal structure in the seal structure of the high-pressure vessel of the present invention, so that the inner diameter of the seal member is reduced.

  For this reason, the sealing structure of the high-pressure vessel of the present invention can ensure hermeticity without causing leakage even when the fluid is filled and discharged at a pressure of 35 MPa or more, and further, a pressure of 90 MPa or more.

  The conventional seal structure using a seal member such as an O-ring or a ring joint gasket uses a seal member having an outer diameter larger than the outer diameter of the opening (fluid flow path) of the high-pressure vessel, whereas the seal structure of the present invention. Then, the sealing member is fitted to the tapered surface provided in the opening of the high-pressure vessel. Thereby, in the seal structure of the present invention, the diameter of the reaction force circle of the seal member (gasket) can be made smaller than that of the conventional one, and the seal structure can be reduced in size and the airtightness can be efficiently secured.

  In the seal structure shown in FIG. 2, since the accessory adjacent to the high-pressure vessel is a connecting pipe, a hole is provided in the seal member as a fluid flow path. The seal structure of the present invention can also be applied when a stopper is used as an accessory.

  FIG. 3 is a cross-sectional view illustrating an example of the configuration in the case of using a stopper as an accessory, which is a high-pressure container sealing structure of the present invention. As shown in the figure, when the accessory is a stopper, a recess 6a for inserting one end of the sealing member into the stopper 6 and a tapered surface 6b for fitting the second tapered surface 5b of the sealing member into the recess. Provide. Thereby, the seal member and the high-pressure container, and the seal part of the seal member and the accessory are fitted with a taper, respectively, and even when filling and releasing the fluid at a pressure of 35 MPa or more, and further a pressure of 90 MPa or more, Airtightness can be ensured without leakage from between the high-pressure vessel 1 and the stopcock 6.

  In the seal structure shown in FIG. 2 and FIG. 3, the cap nut is used to join the high-pressure vessel and the accessory and to bring the seal member, the high-pressure vessel and the accessory into close contact with each other. Then, a seal part can also be stuck by a flange type.

  FIG. 4 is a cross-sectional view illustrating a case where the seal portion of the high-pressure vessel of the present invention is in close contact with a flange mold. The seal structure shown in the figure shows a case where the accessory is a connecting pipe, and includes a flange 7 attached to the threaded portion of the high-pressure vessel, a holding flange 8 that joins the connecting tube to the high-pressure vessel, and a holding flange fixed to the flange. Bolt 9 is used.

  As shown in the figure, the flange 7 is attached to the threaded portion 1c of the high-pressure vessel, and the bolt 9 and the flange 7 are tightened in a state where the connecting pipe 2 is disposed between the high-pressure vessel 1 and the holding flange 8, thereby holding the holding flange. 8 moves to the high-pressure vessel side, the connecting pipe 2 is pressed against the high-pressure vessel, and the seal member comes into close contact with the high-pressure vessel and the connecting tube.

  In the high-pressure container sealing structure of the present invention, it is preferable to use a metal material for the sealing member. As described above, when a rubber material is used in a high-pressure gas environment, blister destruction occurs and durability becomes a problem. Moreover, it occurs in a seal structure using an O-ring made of a conventional rubber material, and the seal member is greatly deformed and comes off from the groove, resulting in a problem that airtightness is lowered. Such a problem that durability and airtightness are lowered can be prevented by using a metal material for the seal member.

  Furthermore, when a rubber material is used for the seal member, the seal member may deteriorate in a high temperature environment, or the seal member may be cured in a cryogenic environment and the airtightness may be reduced. However, a metal material may be used for the seal member. Therefore, it is possible to suppress the problem that the airtightness is lowered in a high temperature environment and a cryogenic environment. As the metal material, for example, an aluminum alloy, stainless steel, low carbon steel, or nickel base alloy can be used.

  When the fluid filled and discharged by the high-pressure vessel is hydrogen gas, the seal member is preferably made of stainless steel of JIS symbol SUS316L. This is because the stainless steel of JIS symbol SUS316L is less affected by hydrogen embrittlement, so that durability can be ensured even when the fluid filled and discharged by the high-pressure vessel is hydrogen.

  In the high pressure vessel seal structure of the present invention, the inclination angle α of the first taper surface and the inclination angle β of the second taper surface of the seal member 5 shown in FIG. The pressure can be determined as appropriate according to the required pressure generated in the seal portion.

  Specifically, when the strengths of the materials of the high pressure vessel and the accessory that are in contact with the seal member are the same, it is preferable that the inclination angle α of the first taper surface and the inclination angle β of the second taper surface of the seal member be the same.

  If the strength of the materials of the high-pressure vessel and the accessory that are in contact with the seal member is different, in order to equalize the required pressure generated in the seal member and the high-pressure vessel, and the seal part of the seal member and the accessory, respectively, It is preferable that the inclination angle α of the first taper surface and the inclination angle β of the second taper surface are different from each other, and the area where the high-pressure vessel or accessory and the seal member are in contact with each other in the seal portion is preferably the same. Specifically, comparing the material strength of the high-pressure vessel and the accessory, the inclination angle of the taper surface of the seal member that contacts the low-strength material is greater than the inclination angle of the taper surface of the seal member that contacts the high-strength material. It is preferable to enlarge it.

  The sealing member of the high-pressure vessel of the present invention is a sealing member used in the above-described sealing structure of the high-pressure vessel of the present invention. For this reason, according to the sealing member of the high-pressure vessel of the present invention, the sealing portion is fitted with a taper, and leakage occurs even when the fluid is filled / released at a pressure of 35 MPa or higher, or even 90 MPa or higher. Airtightness can be ensured without doing so.

  Using the sealing structure of the high-pressure vessel of the present invention and the seal member used therefor, an airtight test was conducted in which the high-pressure vessel was filled with a high-pressure fluid, and the effect of the present invention was verified.

[Test method]
A high-pressure vessel having openings at both ends was used, a connecting pipe was adjacent to one end by the sealing structure shown in FIG. 2, and a stopper was adjacent to the other end by the sealing structure shown in FIG. A pump for supplying fluid to the high-pressure vessel and a pressure gauge were connected to the connection pipe via the pipe. The fluid used was nitrogen gas, which is a nonflammable gas, the seal member was stainless steel of JIS symbol SUS316L, the tightening torque of the cap nut was 110 kgf · m, and the capacity of the high-pressure vessel was 60 L.

  The connecting pipe or stopper was chrome molybdenum steel with JIS symbol SCM435, and the high pressure vessel was nickel chrome molybdenum steel with JIS symbol SNCM439. The strength of the high-pressure vessel and the connecting pipe or stopper is compared, and the inclination angle α of the first taper surface of the sealing member that contacts the high-pressure container having a high strength is set to 30 °, so that the high-pressure container contacts the low-strength connecting tube or stopper. The inclination angle β of the second taper surface of the seal member was 45 °. In addition, the axial lengths of the first taper surface and the second taper surface in the seal member were adjusted, and the area where the high pressure vessel, the connecting pipe or the stopper and the seal member were in contact with each other in the seal portion was made the same.

  The hermetic test was carried out by filling a high-pressure vessel with nitrogen gas until the pressure became 90 MPa with a booster. At this time, every 10 MPa, whether or not nitrogen gas leaked from the seal structure at both ends was confirmed by using a detection liquid in a leak port provided in the cap nut to confirm whether or not bubbles were generated.

  As a comparative example, the opening at both ends of the high-pressure vessel was made into a seal structure using the metal O-ring shown in FIG. At this time, the O-ring was made of JIS symbol SUS316L stainless steel, and the tightening torque of the cap nut was 110 kgf · m. The capacity of the high-pressure vessel was 60 L in Comparative Example 1 and 100 L in Comparative Example 2. The airtight test was performed in Comparative Example 1 by filling with nitrogen gas until the pressure reached 90 MPa, and in Comparative Example 2, filled with nitrogen gas until the pressure reached 72 MPa.

[Evaluation index]
The leak check by the airtight test was performed at 2 places in the present invention example, 22 places in the comparative example 1 and 10 places in the comparative example 2, and the leak occurrence rate was calculated respectively. The leak occurrence rate is expressed as a percentage by dividing the number of locations of the seal structure where the leak occurred by the total number of locations using the seal structure.

[Test results]
FIG. 5 is a graph showing the relationship between the filled fluid pressure and the leak rate (%) in the airtight test using the seal structure of the present invention or the comparative example. From the figure, in Comparative Examples 1 and 2 using conventional O-rings, leakage was observed when the filled fluid pressure exceeded 50 MPa. However, in the seal structure of the present invention example, No leakage occurred until the pressure was 90 MPa.

  Therefore, even when a high pressure vessel is filled with a fluid at a pressure of 35 MPa or more, and further a pressure of 90 MPa or more, the sealing structure of the high pressure vessel of the present invention and the seal member used therefor ensure airtightness without causing leakage. It became clear that we could do it.

  According to the seal structure of the high-pressure vessel of the present invention, the seal member and the high-pressure vessel, and the seal part and the seal part of the accessory are each fitted with a taper, so that the pressure exceeds 35 MPa or more and is 50 MPa or more. Furthermore, even when the fluid is filled / released at a pressure of 90 MPa or more, airtightness can be ensured without causing leakage. Furthermore, by using JIS symbol SUS316L stainless steel as the seal member, blister breakage and hydrogen embrittlement can be prevented, and excellent durability can be ensured.

  The seal member of the high-pressure vessel of the present invention used for this seal structure has a first taper surface and a second taper surface fitted to the high-pressure vessel and the accessory, so that the seal member and the high-pressure vessel, and the seal member and the accessory Each of the seal portions can be fitted using a taper, and even when used in a seal structure that fills and discharges fluid at a pressure of 35 MPa or more, and further a pressure of 90 MPa or more, no leakage occurs. Airtightness can be ensured.

  Therefore, if the high pressure vessel seal structure and the seal member used therefor of the present invention are applied to a pressure accumulator for a hydrogen station such as a fuel cell vehicle, a gas tank can be filled with higher pressure hydrogen gas. For this reason, the sealing structure of the high-pressure vessel of the present invention and the sealing member used therefor can greatly contribute to the improvement of the filling capacity of the gas tank used in the fuel cell vehicle.

1: High-pressure vessel, 1a: Container portion, 1b: Opening portion, 1c: Screw portion, 1d: Joining surface,
1e: taper surface of the high-pressure vessel, 2: connection pipe, 2a: groove, 2b: opening,
2c: tapered surface of connecting pipe, 3: O-ring, 4: cap nut,
4a: leak port, 5: seal member, 5a: first taper surface,
5b: 2nd taper surface, 6: Stopcock, 6a: Recessed part, 6b: Tapered surface of stopcock,
7: Flange, 8: Holding flange, 9: Bolt,
α: inclination angle of the first taper surface, β: inclination angle of the second taper surface

Claims (4)

A sealing structure that seals between an end face of a high-pressure vessel and an end face of an accessory by disposing a seal member between the high-pressure vessel and an accessory adjacent thereto,
The cylindrical seal member has a first taper surface and a second taper surface on the outer periphery, and has a hole through which fluid flows in an axis,
Wherein the first tapered surface, the Ri diameter is smaller as the second distance from the tapered surface, diametrically contracted in the first tapered surface is formed on one end face and communicating a so that the seal member,
The second tapered surface, said Ri diameter is smaller as the first distance from the tapered surface, diametrically contracted in the second tapered surface is formed on the other end face and communicating a so that the seal member,
Wherein the first tapered surface is I because fitting engagement in a tapered surface provided in the opening of the high-pressure vessel becomes the sealing surface,
Sealing structure for a high-pressure container, wherein said second tapered surface is the opening of the accessory or is I because fitting engagement in a tapered surface provided on the concave sealing surface.   The seal structure for a high-pressure vessel according to claim 1, wherein the seal member is made of a metal material. A cylindrical sealing member for sealing between the end face of the high pressure vessel and the end face of the accessory by being disposed between the high pressure vessel and the accessory adjacent thereto,
A first taper surface that is fitted with a taper surface provided at the opening of the high-pressure vessel to become a seal surface and a second taper that is fitted with a taper surface provided at the opening or the recess of the accessory. Having a surface on the outer periphery and a hole into which the fluid flows
Wherein the first tapered surface has a diameter smaller as the distance from the second tapered surface, diametrically contracted in the first tapered surface is formed on one end face and communicating such so that,
The second tapered surface, the diameter as the first distance from the tapered surface is reduced, the high-pressure vessel seal, wherein the diametrically contracted in the second tapered surface is formed on the other end face and communicating a so that Element.   The high-pressure vessel sealing member according to claim 3, wherein the sealing member is made of a metal material.

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