阅读说明：本技术 一种用于高压气体介质的防泄漏阀门 (Anti-leakage valve for high-pressure gas medium ) 是由 侯峰伟 吴斌 洪进元 章起华 洪菊芬 张峻宾 陈磊 吕超 洪佳福 曹德胜 于 2020-05-11 设计创作，主要内容包括：本发明公开了一种用于高压气体介质的防泄漏阀门,包括阀体、阀盖和阀杆,其中,所述阀盖和阀杆的连接处设有填料密封结构；所述填料密封结构包括从下到上依次套设在阀杆外周的填料衬套、填料组、填料压套和填料压板；所述填料衬套和填料组填充阀杆与阀盖间的填料空间；所述填料压套与阀盖的接触面设有外O型圈,所述填料压套与阀杆的接触面设有内O型圈；所述阀体和阀盖的连接处设有中法兰密封结构；所述中法兰密封结构包括中法兰垫片和阀盖密封圈。本发明在填料密封处通过填料组进行阻隔,在填料压套的内孔与外圆处设置密封槽和O型圈,中法兰密封处设置两道O型圈；通过多道密封,防止泄漏。(The invention discloses a leakage-proof valve for high-pressure gas media, which comprises a valve body, a valve cover and a valve rod, wherein a packing sealing structure is arranged at the joint of the valve cover and the valve rod; the packing sealing structure comprises a packing bushing, a packing group, a packing pressing sleeve and a packing pressing plate which are sequentially sleeved on the periphery of the valve rod from bottom to top; the packing bushing and the packing group are used for filling a packing space between the valve rod and the valve cover; an outer O-shaped ring is arranged on the contact surface of the packing pressing sleeve and the valve cover, and an inner O-shaped ring is arranged on the contact surface of the packing pressing sleeve and the valve rod; a middle flange sealing structure is arranged at the joint of the valve body and the valve cover; the middle flange sealing structure comprises a middle flange gasket and a valve cover sealing ring. The invention separates the packing seal position by the packing group, a seal groove and an O-shaped ring are arranged at the inner hole and the outer circle of the packing pressing sleeve, and two O-shaped rings are arranged at the seal position of the middle flange; leakage is prevented by multiple seals.)

1. A leakproof valve for high-pressure gas medium comprises a valve body, a valve cover and a valve rod, and is characterized in that a packing sealing structure is arranged at the joint of the valve cover and the valve rod; the packing sealing structure comprises a packing bushing, a packing group, a packing pressing sleeve and a packing pressing plate which are sequentially sleeved on the periphery of the valve rod from bottom to top; the packing pressing sleeve is fixedly pressed by the packing pressing plate; an outer O-shaped ring is arranged on the contact surface of the packing pressing sleeve and the valve cover, and an inner O-shaped ring is arranged on the contact surface of the packing pressing sleeve and the valve rod; a middle flange sealing structure is arranged at the joint of the valve body and the valve cover; the middle flange sealing structure comprises a middle flange gasket and a valve cover sealing ring.

2. A leak-proof valve for high-pressure gas media as in claim 1, wherein an outer sealing groove is provided at the contact of the outer wall of the packing gland and the valve cover, the height and depth of the outer sealing groove being matched with an outer O-ring, the outer O-ring being disposed in the outer sealing groove; the packing pressing sleeve is characterized in that an annular inner sealing groove is formed in the middle of the inner wall of the packing pressing sleeve, the height and the depth of the inner sealing groove are matched with an inner O-shaped ring, and the inner O-shaped ring is arranged in the inner sealing groove.

3. A leak-proof valve for high-pressure gaseous media as in claim 1, wherein the packing press sleeve has a top outer diameter greater than a bottom outer diameter, the packing press sleeve has a top surface that is a circular table top, the packing press plate has a bottom surface that mates with the top surface of the packing press sleeve, and the packing press plate is secured to the top of the valve cover by press plate bolts and press plate nuts.

4. A leak-proof valve for high-pressure gaseous media as in claim 1, wherein said mid-flange gasket is disposed inside the horizontal interface of the valve cover with the valve body, said valve cover having a boss inserted into the valve body, said valve cover sealing ring being disposed outside the interface of the boss with the valve body; the valve cover is locked to the valve body through a valve cover bolt and a valve cover nut.

5. A leak-proof valve for high pressure gaseous media as in claim 4, wherein said mid-flange gasket is a wound gasket, said mid-flange gasket being wound from stainless steel and flexible graphite; the valve cover sealing ring comprises a first O-shaped ring and a second O-shaped ring which are arranged in parallel, and the first O-shaped ring and the second O-shaped ring are made of ethylene propylene diene monomer rubber, nitrile butadiene rubber or fluororubber.

6. A leak-proof valve for high-pressure gaseous media as in claim 1, wherein the roughness of the interface of said valve cover and packing set is greater than or equal to ra 1.6; the roughness of the contact surface of the valve cover and the valve body is more than or equal to Ra1.6.

7. A leak resistant valve for high pressure gas media as in claim 1, wherein said valve stem is made of 17-4PH stainless steel, said valve stem is hard chrome plated on its outer surface, and said valve stem has an outer surface roughness of greater than or equal to ra0.4.

8. A leak-proof valve for high-pressure gaseous media as recited in claim 1, wherein said packing set is comprised of Inconel718 precipitation hardening nichrome; the material of the packing gland and the packing pressure plate is 410 stainless steel.

Technical Field

The invention relates to a leakage-proof valve, in particular to a leakage-proof valve for high-pressure gas medium.

Background

In order to prevent the medium from leaking outside, the sealing at the middle flange and the stuffing box is also important except for the pressure boundary formed by the pressure bearing parts such as the valve body, the valve cover and the like, and the sealing at the middle flange and the stuffing box often determines whether the valve can run safely and reliably. On the valve seal, the packing and the gasket are both fillers for preventing the medium from leaking out. The packing is used to fill the space of the packing chamber of the valve cover to prevent the medium from leaking through the valve stem and the packing chamber space of the valve cover, and the gasket is used to fill all the unevenness between two joint surfaces (such as the sealing surface between the valve body and the valve cover) to prevent the medium from leaking from the joint surfaces.

The common flange gaskets at present comprise non-metal gaskets, semi-metal gaskets and metal gaskets. The non-metal gasket comprises a flexible graphite plate, a polytetrafluoroethylene plate, a non-asbestos gasket, a rubber gasket and the like, the semi-metal gasket is formed by combining a metal material and a non-metal material, and comprises a flexible graphite composite reinforced plate gasket, a metal-coated gasket and the like; the metal gasket includes a metal tooth-shaped gasket, an octagonal gasket, a lens gasket and the like, and is generally used in high-temperature occasions. Common filler varieties comprise a high-temperature and high-pressure valve special packing, a graphite filled PTFE fiber packing, a wear-resistant special packing, a pure PTFE packing, a universal synthetic fiber packing and the like, and different kinds of packing are selected according to different occasions.

The sealing material can be widely used in various occasions, and can be used in high-temperature high-pressure, low-temperature low-pressure and even some vacuum fields, however, for high-pressure gas, the sealing material is not applicable to all, the gas is a compressible and expandable fluid without shape and volume, the distance between gas molecules is large, and the gas molecules are influenced by the volume, the temperature and the pressure, so that effective sealing is realized by simply selecting a filler and a gasket made of proper materials, and the leakage is avoided. Accordingly, the prior art is yet to be improved and developed.

Disclosure of Invention

The invention aims to solve the technical problem of providing a leakage-proof valve for high-pressure gas medium, wherein a sealing groove and a sealing ring are additionally arranged at a middle flange and a stuffing box, and effective sealing is realized through a multi-sealing mechanism.

The invention adopts the technical scheme that a leakage-proof valve for high-pressure gas medium is provided to solve the technical problems, and comprises a valve body, a valve cover and a valve rod, wherein a filler sealing structure is arranged at the joint of the valve cover and the valve rod; the packing sealing structure comprises a packing bushing, a packing group, a packing pressing sleeve and a packing pressing plate which are sequentially sleeved on the periphery of the valve rod from bottom to top; the packing pressing sleeve is fixedly pressed by the packing pressing plate; an outer O-shaped ring is arranged on the contact surface of the packing pressing sleeve and the valve cover, and an inner O-shaped ring is arranged on the contact surface of the packing pressing sleeve and the valve rod; a middle flange sealing structure is arranged at the joint of the valve body and the valve cover; the middle flange sealing structure comprises a middle flange gasket and a valve cover sealing ring.

Further, an outer sealing groove is formed in the contact position of the outer wall of the packing pressing sleeve and the valve cover, the height and the depth of the outer sealing groove are matched with those of an outer O-shaped ring, and the outer O-shaped ring is arranged in the outer sealing groove; the packing pressing sleeve is characterized in that an annular inner sealing groove is formed in the middle of the inner wall of the packing pressing sleeve, the height and the depth of the inner sealing groove are matched with an inner O-shaped ring, and the inner O-shaped ring is arranged in the inner sealing groove.

Furthermore, the outer diameter of the top of the packing pressing sleeve is larger than that of the bottom of the packing pressing sleeve, the top surface of the packing pressing sleeve is a round table surface, the bottom surface of the packing pressing plate is matched with the top surface of the packing pressing sleeve, and the packing pressing plate is locked on the top of the valve cover through a pressing plate bolt and a pressing plate nut.

Furthermore, the middle flange gasket is arranged on the inner side of a horizontal contact surface between the valve cover and the valve body, the valve cover is provided with a boss inserted into the valve body, and the valve cover sealing ring is arranged on the outer side of the contact surface between the boss and the valve body; the valve cover is locked to the valve body through a valve cover bolt and a valve cover nut.

Furthermore, the middle flange gasket is a winding gasket and is formed by winding stainless steel and flexible graphite; the valve cover sealing ring comprises a first O-shaped ring and a second O-shaped ring which are arranged in parallel, and the first O-shaped ring and the second O-shaped ring are made of ethylene propylene diene monomer rubber, nitrile butadiene rubber or fluororubber.

Further, the roughness of the contact surface of the valve cover and the packing group is more than or equal to Ra1.6; the roughness of the contact surface of the valve cover and the valve body is more than or equal to Ra1.6.

Further, the valve rod is made of 17-4PH stainless steel, hard chromium plating treatment is carried out on the outer surface of the valve rod, and the roughness of the outer surface of the valve rod is more than or equal to Ra0.4.

Further, the filler group is made of Inconel718 precipitation hardening type nickel-chromium-iron alloy; the material of the packing gland and the packing pressure plate is 410 stainless steel.

Compared with the prior art, the invention has the following beneficial effects: according to the leakage-proof valve for the high-pressure gas medium, the packing group is used for blocking at the packing sealing position, the packing group is made of a pressure-resistant and wear-resistant Inconel718 material, and most of medium pressure is eliminated at the packing position by utilizing the labyrinth action of the packing group, so that leakage is prevented; the inner hole and the outer circle of the packing pressing sleeve are provided with a sealing groove and an O-shaped ring, and the two sealing mechanisms ensure that a medium cannot leak from the packing in the action process of the valve rod; two O-shaped rings are arranged at the sealing position of the middle flange; when the medium flows outwards from the valve cavity, the two O-shaped rings seal and block the medium from further flowing outwards, and the valve cover and the winding gasket at the valve body are further protected to prevent leakage.

Drawings

FIG. 1 is a schematic structural view of a leak-proof valve for high-pressure gaseous media according to an embodiment of the present invention;

FIG. 2 is a schematic view of a packing arrangement according to an embodiment of the present invention;

fig. 3 is a schematic view of a middle flange sealing structure according to an embodiment of the present invention.

In the figure:

1. a valve cover; 2. a filler bushing; 3. a filler group; 4. a valve stem; 5. an outer O-ring; 6. an inner O-shaped ring; 7. pressing and sleeving the filler; 8. a packing press plate; 9. a platen bolt; 11. a valve body; 12. a first O-ring; 13. a second O-ring; 14. a middle flange gasket; 16. valve gap bolt.

Detailed Description

The invention is further described below with reference to the figures and examples.

FIG. 1 is a schematic view of a leak-proof valve for high-pressure gaseous media according to an embodiment of the present invention; FIG. 2 is a schematic view of a packing arrangement according to an embodiment of the present invention; fig. 3 is a schematic view of a middle flange sealing structure according to an embodiment of the present invention. The embodiment of the leakage prevention valve for high-pressure gaseous medium is a flow distribution valve, but the present invention is not limited to the flow distribution valve.

Referring to fig. 1, fig. 2 and fig. 3, the leakproof valve for high-pressure gas medium according to the embodiment of the invention comprises a valve body 11, a valve cover 1 and a valve rod 4, wherein a packing sealing structure is arranged at the joint of the valve cover 1 and the valve rod 4; the packing sealing structure comprises a packing bush 2, a packing group 3, a packing pressing sleeve 7 and a packing pressing plate 8 which are sequentially sleeved on the periphery of the valve rod 4 from bottom to top; the packing bush 2 and the packing group 3 are wrapped on the periphery of the valve rod 4 to fill a packing space between the valve rod 4 and the valve cover 1, the bottom of the packing pressing sleeve 7 is inserted into the packing space and presses the packing bush 2 and the packing group 3 to the packing space, and the packing pressing plate 8 presses and fixes the packing pressing sleeve 7; an outer O-shaped ring 5 is arranged on the contact surface of the packing pressing sleeve 7 and the valve cover 1, and an inner O-shaped ring 6 is arranged on the contact surface of the packing pressing sleeve 7 and the valve rod 4; a middle flange sealing structure is arranged at the joint of the valve body 11 and the valve cover 1; the middle flange sealing structure comprises a middle flange gasket 4 and a valve cover sealing ring.

With reference to fig. 2, in the leakproof valve for high-pressure gas medium according to the embodiment of the present invention, an outer sealing groove is disposed at a contact position between an outer wall of the packing pressing sleeve 7 and the valve cover 1, a height and a depth of the outer sealing groove are matched with those of an outer O-ring 5, and the outer O-ring 5 is disposed in the outer sealing groove; the middle part of the inner wall of the packing pressing sleeve 7 is provided with an annular inner sealing groove, the height and the depth of the inner sealing groove are matched with the inner O-shaped ring 6, and the inner O-shaped ring 6 is arranged in the inner sealing groove.

Specifically, in the anti-leakage valve for the high-pressure gas medium, the outer diameter of the top of the packing pressing sleeve 7 is larger than that of the bottom of the packing pressing sleeve, the top surface of the packing pressing sleeve 7 is a circular table surface, and the bottom surface of the packing pressing plate 8 is matched with the top surface of the packing pressing sleeve, so that the bearing area is increased, and the positioning is more convenient; and the packing pressing plate 8 is locked at the top of the valve cover 1 through a pressing plate bolt 9 and a pressing plate nut.

The anti-leakage valve for the high-pressure gas medium of the embodiment of the invention has the following sealing process of the packing sealing structure: in the opening and closing process of the valve, when a medium flows outwards from a gap between the valve rod 4 and the valve cover 1, the medium is firstly blocked by the packing group 3, and most of the medium pressure is eliminated at the packing group by using the labyrinth action of the packing group 3, so that further leakage is prevented; two sealing mechanisms are formed by the O-shaped rings on the inner wall and the outer wall of the packing pressing sleeve 7, so that the medium cannot leak from the packing in the action process of the valve rod 4.

With reference to fig. 3, in the leakproof valve for high-pressure gas medium according to the embodiment of the present invention, the middle flange gasket 14 is disposed on the inner side of the horizontal contact surface between the valve cover 1 and the valve body 11, the valve cover 1 is provided with a boss inserted into the valve body, and the valve cover sealing ring is disposed on the outer side of the contact surface between the boss and the valve body 1; the bonnet 1 is locked to the valve body through a bonnet bolt 16 and a bonnet nut, so that a flange gasket 14 is plastically deformed to form a seal and prevent the leakage of a medium.

Specifically, in the anti-leakage valve for high-pressure gas medium of the embodiment of the invention, the middle flange gasket 14 is a wound gasket, and the middle flange gasket 14 is formed by winding stainless steel and flexible graphite; the valve cover sealing ring comprises a first O-shaped ring 12 and a second O-shaped ring 13 which are arranged in parallel, and the first O-shaped ring 12 and the second O-shaped ring 13 are made of ethylene propylene diene monomer, nitrile butadiene rubber or fluororubber.

The anti-leakage valve for high-pressure gas medium of the embodiment of the invention has the following sealing process of the sealing structure of the middle flange: when the medium flows outwards from the valve cavity, the medium firstly passes through the first O-shaped ring 12, the first O-shaped ring 12 plays a role in sealing and blocking the medium from further flowing outwards, the second O-shaped ring 13 also plays the same role, and the valve cover 5 and the middle flange gasket 14 at the valve body 1 are used as a third protection.

Preferably, the roughness of the contact surface of the valve cover 1 and the packing group 3 is greater than or equal to Ra1.6; the roughness of the contact surface of the valve cover 1 and the valve body 11 is more than or equal to Ra1.6.

Preferably, the first and second electrodes are; the valve rod is made of 17-4PH stainless steel, the outer surface of the valve rod 4 is plated with hard chromium, the roughness of the outer surface of the valve rod 4 is more than or equal to Ra0.4, the hardness and the wear resistance of the surface of the valve rod are improved, the friction coefficient of the valve rod with a filler is reduced, and the execution thrust is reduced.

Preferably, the material of the packing group is pressure-resistant and wear-resistant Inconel718 precipitation hardening type nickel-chromium-iron alloy, and the material of the packing gland and the packing pressing plate is 410 stainless steel. The Inconel718 precipitation hardening type nickel-chromium-iron alloy has good comprehensive performance within the temperature range of-253-700 ℃, has the yield strength below 650 ℃ at the first position of the deformation high-temperature alloy, and has good fatigue resistance, radiation resistance, oxidation resistance, corrosion resistance, good processability and good welding performance. Can manufacture various parts with complex shapes, and has wide application in aerospace, nuclear energy, petroleum industry and extrusion dies in the temperature range.

In summary, in the leakproof valve for high-pressure gas media according to the embodiment of the invention, the packing group 3 is used for blocking at the packing seal position, the packing group 3 is made of pressure-resistant and wear-resistant Inconel718 material, and most of the pressure of the media is eliminated at the packing position by the labyrinth action of the packing group 3, so that leakage is prevented; the inner hole and the outer circle of the packing pressing sleeve 7 are provided with a sealing groove and an O-shaped ring, and the two sealing mechanisms ensure that a medium cannot leak from the packing in the action process of the valve rod; the middle flange sealing position is provided with two O-shaped rings, when the medium flows outwards from the valve cavity, the two O-shaped rings seal and block the medium from further flowing outwards, and the valve cover 1 and the winding gasket at the valve body 11 position are further protected to prevent leakage.

Although the present invention has been described with respect to the preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.