CN112178211A

CN112178211A - Ultralow-temperature electromagnetic pneumatic stop valve

Info

Publication number: CN112178211A
Application number: CN202010915203.9A
Authority: CN
Inventors: 赵丰显; 王程勇; 李晓艳; 张珂; 叶飞; 杨钱
Original assignee: Hubei Sanjiang Aerospace Hongfeng Control Co Ltd
Current assignee: Hubei Sanjiang Aerospace Hongfeng Control Co Ltd
Priority date: 2020-09-03
Filing date: 2020-09-03
Publication date: 2021-01-05
Anticipated expiration: 2040-09-03
Also published as: CN112178211B

Abstract

The invention discloses an ultralow temperature electromagnetic pneumatic stop valve which comprises a valve body, a valve rod, a valve seat, an air cylinder and an electromagnetic directional valve, wherein the valve body is provided with a valve cavity, the side wall of the valve body is provided with an air inlet channel, and the lower end of the valve cavity is used as an air outlet channel; the lower end of the valve rod is provided with a sealing ring, the outlet end of the valve body at the air inlet channel is provided with a sealing strip, the air cylinder is provided with a cylinder body and a piston assembly, the upper end of the valve rod penetrates into the cylinder body from the lower end of the cylinder body to be fixedly connected with the piston assembly, the piston assembly divides the inner cavity of the cylinder body into a sealing cavity I and a sealing cavity II positioned below the sealing cavity I, and the sealing cavity I and the sealing cavity II are respectively connected with the electromagnetic directional valve; the electromagnetic directional valve is used for supplying air to the sealing cavity I or the sealing cavity II, so that the piston assembly and the valve rod are driven to move up and down to open or close the stop valve. The invention has the advantages of compact structure, small volume, high reliability and the like, and is suitable for transportation, storage and pipeline use of cryogenic media such as liquid oxygen, liquid nitrogen, Liquefied Natural Gas (LNG) and the like.

Description

Ultralow-temperature electromagnetic pneumatic stop valve

Technical Field

The invention belongs to the field of valves, and particularly relates to an ultralow-temperature electromagnetic pneumatic stop valve.

Background

With the development of technology, the pipeline systems for transporting, storing and using cryogenic media such as liquid oxygen, liquid nitrogen, Liquefied Natural Gas (LNG) and the like are gradually intelligentized, valves required by a control switch are gradually replaced by a low-temperature manual valve, and the low-temperature stop valve is generally applied to a working environment with the temperature lower than-40 ℃, for example: petrochemical, air separation, natural gas and other industries. Therefore, the low-temperature stop valve needs to achieve the effects of long working time and good sealing performance at the temperature suitable for the surrounding environment.

When the low-temperature stop valve bears pressure and the drift diameter of the low-temperature stop valve is large, the existing low-temperature stop valve is low in reliability and can leak. The leakage is caused by the fact that under the influence of low temperature of cryogenic medium, a sealing ring (plastic) of a low-temperature stop valve and a sealing ring (metal material) are contracted and hardened due to the fact that the thermal expansion coefficients of materials of the sealing ring (plastic) and a valve seat (metal material) are different, the elastic force of a compression spring is not enough to overcome the deformation of the sealing ring to maintain the contact force required by the contact between the sealing ring and a valve body, and the leakage is the root. Therefore, leakage events occur frequently in the running process of the cryogenic medium storage and transportation tank car at present, particularly valves arranged in an operation box and the like are high-risk parts of the cryogenic medium storage and transportation tank car for leakage, and if the sealing performance is poor, great risks exist in storage and transportation of the cryogenic medium.

Disclosure of Invention

Aiming at the defects or improvement requirements of the prior art, the invention provides an ultralow temperature electromagnetic pneumatic stop valve, which cancels a compression spring for driving a valve rod and a valve core to move in the traditional stop valve, thereby effectively preventing leakage, improves a plurality of aspects such as the structure, the arrangement, the sealing mode and the like of key components of the stop valve, solves the problem of the reliability of the motion dynamic seal of the ultralow temperature medium valve rod through the application of a corrugated pipe assembly, realizes the compact structure and the light weight through the optimization of the whole structure, tests show that the ultralow temperature electromagnetic pneumatic stop valve can be suitable for the working conditions of the pressure of (3-15) MPa and the drift diameter of (15-50) mm, has the advantages of compact structure, reliable seal, light weight, convenient assembly and maintenance and the like compared with similar products, and has the advantages of.

To achieve the above object, according to one aspect of the present invention, there is provided an ultra-low temperature electromagnetic pneumatic stop valve, characterized by comprising a valve body, a valve stem, a valve seat, a cylinder, and an electromagnetic directional valve, wherein,

the valve body is provided with a valve cavity which is communicated up and down, the side wall of the valve body is provided with an air inlet channel communicated with the valve cavity, and the lower end of the valve cavity is used as an air outlet channel;

the valve seat is mounted on the valve body and located in the valve cavity;

the valve rod is vertically arranged, the upper end and the lower end of the valve rod penetrate through the valve seat, a sealing ring is arranged at the lower end of the valve rod, a sealing strip is arranged at the outlet end of the air inlet channel of the valve body, and the sealing ring is positioned above the sealing strip;

the cylinder is provided with a cylinder body and a piston assembly arranged in the cylinder body, the upper end of the valve rod penetrates into the cylinder body from the lower end of the cylinder body to be fixedly connected with the piston assembly, the piston assembly divides an inner cavity of the cylinder body into a sealing cavity I and a sealing cavity II located below the sealing cavity I, and the sealing cavity I and the sealing cavity II are respectively connected with the electromagnetic directional valve through connecting pipes;

the electromagnetic reversing valve is installed on the air cylinder and used for being connected with an air source and supplying air to the sealing cavity I or the sealing cavity II through the air source, so that the piston assembly and the valve rod are driven to move up and down, and the sealing ring is separated from or contacted with the sealing belt to open or close the outlet end of the air inlet channel.

Preferably, the inner wall of the valve seat is provided with a step A, a packing component I is arranged between the valve rod and the valve seat, the packing component I comprises a supporting block I, a packing I, a check block I, a spring I and a compression nut I which are sequentially arranged from bottom to top, wherein the lower end of the supporting block I is a horizontal plane, the upper end of the supporting block I is inverted V-shaped, the lower end of the supporting block I is placed on the step A, the packing I is also in an inverted V-shaped structure and is placed on the supporting block I, the upper end of the check block I is a horizontal plane, the lower end of the check block I is also inverted V-shaped, the lower end of the check block I is pressed on the packing I, the spring I is pressed on the upper end of the check block I, the compression nut I is in threaded connection with the inner wall of the valve seat and compresses the spring I, and the step A and the supporting block, the deep cooling medium entering the air inlet channel enters the filler I through the valve cavity and the air guide hole A, so that the filler I contracts in cold and is further deformed through the pretightening force of the spring I to realize reliable sealing.

Preferably, a step B is arranged on the inner wall of the valve body, a shaft shoulder a is arranged on the outer wall of the valve seat, a flooding plug seal assembly i is arranged between the valve seat and the valve body, the flooding plug seal assembly i comprises a check ring i, a flooding plug seal i and a support ring which are sequentially arranged from bottom to top, the check ring i is placed on the step B, the flooding plug seal i is placed on the check ring i with an opening facing downwards, the support ring is placed on the flooding plug seal i, and the shaft shoulder a of the valve seat is matched with the step B of the valve body to clamp the flooding plug seal assembly i;

there is the clearance between disk seat and the valve body, be provided with air guide hole B on the retaining ring I to let the cryrogenic medium that gets into in the inlet channel get into through this clearance and air guide hole B the general stopper seals the opening of I, thereby lets general stopper seal I further expansion and realize reliable sealing.

Preferably, the cylinder body is provided with a stepped hole with a large upper part and a small lower part, the stepped hole penetrates through the piston and is provided with a large hole and a small hole, and the piston, the sealing cavity I and the sealing cavity II are all positioned in the large hole of the stepped hole;

a step C is arranged on the inner wall of the cylinder body;

a packing component II is arranged between the valve rod and the cylinder body and is positioned in the small hole of the stepped hole, the packing component II comprises a supporting block II, a packing II, a block II, a spring II and a compression nut II which are sequentially arranged from bottom to top, wherein the lower end of the supporting block II is a horizontal plane, the upper end of the supporting block II is a V-shaped with an upward opening, the lower end of the supporting block II is placed on the step C, the packing II is also in a V-shaped structure and is placed on the supporting block II, the upper end of the block II is a horizontal plane, the lower end of the block II is pressed on the packing II, the spring II is pressed on the upper end of the block II, the compression nut II is in threaded connection with the inner wall of the cylinder body and compresses the spring II, a gas guide hole C is arranged on the block II so that control gas entering the sealing cavity II enters the packing II through the small hole of the stepped hole and the gas guide hole C of the block II, therefore, the filler II is shrunk and is further deformed by the pretightening force of the spring II to realize reliable sealing.

Preferably, a step D is arranged on the inner wall of the piston, a packing component III is arranged between the upper end of the valve rod and the piston, the packing component III comprises a supporting block III, a packing III, a stop block III, a spring III and a compression nut III which are sequentially arranged from bottom to top, the lower end of the supporting block III is a horizontal plane, the upper end of the supporting block III is in an inverted V shape, the lower end of the supporting block III is placed on the step D, the packing III is also in an inverted V shape structure, the packing III is placed on the supporting block III, the upper end of the stop block III is in a horizontal plane, the lower end of the stop block III is also in an inverted V shape, the lower end of the stop block III is pressed on the packing III, the spring III is pressed on the upper end of the stop block III, the compression nut III is in threaded connection with the valve seat and compresses the spring III, and the step D and the, so that control gas entering the sealing cavity II enters the filler III through the large hole of the stepped hole and the air guide hole D, and the filler III is shrunk and further deformed through the pretightening force of the spring II to realize reliable sealing.

Preferably, the valve rod locking device further comprises a locking plug screw and a locking nut, wherein an external thread of the locking plug screw is connected with the large hole of the stepped hole, an internal thread of the locking nut is connected with the upper end of the valve rod and is pressed on the compression nut III to fix the upper end of the valve rod, and air flow through holes are distributed in the locking plug screw and are used for enabling control air to enter the large hole of the stepped hole to push the piston and the valve rod to move downwards.

Preferably, the piston assembly comprises a piston and a flooding plug assembly II, and the flooding plug assembly II is sleeved on the piston to realize the sealing of the piston and the cylinder;

a shaft shoulder B is arranged on the piston;

the universal plug seal assembly II comprises an elastic check ring II, a universal plug seal II and a check ring II which are sleeved on the piston, the elastic check ring II is matched with the shaft shoulder B to clamp the universal plug seal II and the check ring II, the check ring II is positioned between the elastic check ring II and the universal plug seal II, and an opening of the universal plug seal II faces to the check ring II;

and the check ring II is provided with an air guide hole E so that control air entering the inner cavity of the cylinder body enters the opening of the flooding plug seal II through the air guide hole E, and the flooding plug seal II is further expanded to realize reliable sealing.

Preferably, the bottom of cylinder body is provided with annular positioning groove, the top of disk seat is provided with annular location boss, annular location boss stretches into in the annular positioning groove, realize the location of disk seat, and still install sealed I of filling up in the annular positioning groove.

Preferably, a step E for bearing the valve seat is arranged on the valve body, and a sealing gasket II is arranged on the step E.

Preferably, the cylinder body includes the cylinder barrel and installs the piston cap at the cylinder barrel top, install sealed pad III between the cylinder barrel with the piston cap, the solenoid directional valve is installed on the piston cap, and install thermal-insulated cushion between the solenoid directional valve and the piston cap.

In general, compared with the prior art, the above technical solution contemplated by the present invention can achieve the following beneficial effects:

1) the electromagnetic directional valve can be connected with an air source, the piston can be driven to move by introducing control air into the sealing cavity I and the sealing cavity II of the cylinder body of the stop valve, so that the valve rod can move along with the control air, the sealing ring on the valve core can be in contact with and separated from the sealing strip of the valve body, the outlet end of the air inlet channel is opened or closed, the opening and closing of the stop valve are controlled, and the reliability is high.

2) The invention abandons the structure that the valve rod is driven to move by a compression spring to realize the opening and closing of the stop valve on the traditional stop valve, but controls the air to act on the piston to enable the sealing ring on the valve rod to contact with the sealing belt to realize the closing of the valve, thereby effectively preventing the leakage of the cryogenic medium.

3) The universal plug seals are respectively arranged between the piston and the cylinder body, between the valve seat and the valve body, are self-pressurizing sealing rings, are internally provided with compensation springs, and can press the sealed part so as to form excellent sealing effect and further prevent leakage of control gas and cryogenic medium. In addition, still set up the packing subassembly between piston and valve rod, disk seat and the valve rod, can let the packing further compress through the shrinkage of packing and the pretightning force of spring, realize better sealed.

4) The locking nut is provided with the airflow through hole, and can enter the large hole of the stepped hole to apply acting force, so that the acting force can be applied to the valve rod together with the control gas entering the sealing cavity I, namely, the locking nut can apply downward acting force to the valve rod through the control gas on the two passages, reliable sealing can be realized, and leakage of a cryogenic medium can be effectively prevented.

5) The invention has the advantages of compact structure, small volume, high reliability and the like, and is suitable for transportation, storage and pipeline use of cryogenic media such as liquid oxygen, liquid nitrogen, Liquefied Natural Gas (LNG) and the like.

Drawings

FIG. 1 is a cross-sectional view of the present invention;

FIG. 2 is a cross-sectional view of the packing assembly of the present invention;

fig. 3 is a cross-sectional view of the piston assembly of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

As shown in fig. 1 to 3, an ultralow temperature electromagnetic pneumatic stop valve comprises a valve body 1, a valve rod 3, a valve seat 4, a cylinder and an electromagnetic directional valve 19, wherein,

the valve body 1 is provided with a valve cavity which is communicated up and down, the side wall of the valve body 1 is provided with an air inlet channel 22 communicated with the valve cavity, and the lower end of the valve cavity is used as an air outlet channel 23;

the valve seat 4 is arranged on the valve body 1 and is positioned in the valve cavity;

the valve rod 3 is vertically arranged, the upper end and the lower end of the valve rod both penetrate through the valve seat 4, the lower end of the valve rod 3 is provided with a sealing ring 2, the outlet end of the valve body 1 of the air inlet channel 22 is provided with a sealing strip, and the sealing ring 2 is positioned above the sealing strip;

the cylinder is provided with a cylinder body 11 and a piston assembly 13 arranged in the cylinder body 11, the upper end of the valve rod 3 penetrates into the cylinder body 11 from the lower end of the cylinder body 11 and is fixedly connected with the piston assembly 13, the piston assembly 13 divides an inner cavity of the cylinder body 11 into a sealing cavity I and a sealing cavity II positioned below the sealing cavity I, and the sealing cavity I and the sealing cavity II are respectively connected with the electromagnetic directional valve 19 through connecting pipes;

and the piston cover 17 is provided with a control air port A which is communicated with the sealing cavity I and used for controlling air charging and discharging of the sealing cavity I.

And a control air port B is arranged at the bottom of the cylinder body 11 and communicated with the sealing cavity II for controlling air charging and discharging of the sealing cavity II. The port A of the electromagnetic directional valve 19 is connected and communicated with the control air port A on the piston cover 17 through a port A connecting pipe 20, and the port B of the electromagnetic directional valve 19 is connected and communicated with the control air port A on the cylinder body 11 through a port B connecting pipe 21.

The electromagnetic directional valve 19 is installed on the cylinder and used for being connected with an air source and supplying air to the sealing cavity I or the sealing cavity II through the air source, so that the piston assembly 13 and the valve rod 3 are driven to move up and down, and the sealing ring 2 is separated from or contacted with the sealing strip to open or close the outlet end of the air inlet channel 22.

Further, a step A is arranged on the inner wall of the valve seat 4, a packing component I5 is arranged between the valve rod 3 and the valve seat 4, the packing component I5 comprises a supporting block I51, a packing I52, a stop block I53, a spring I54 and a compression nut I55 which are sequentially arranged from bottom to top, wherein the lower end of the supporting block I51 is a horizontal plane, the upper end of the supporting block I51 is inverted V-shaped, the lower end of the supporting block I51 is placed on the step A, the packing I52 is also in an inverted V-shaped structure, the packing I52 is placed on the supporting block I51, the upper end of the stop block I53 is a horizontal plane, the lower end of the stop block I53 is also inverted V-shaped, the lower end of the stop block I53 is pressed on the packing I52, the spring I54 is pressed on the upper end of the stop block I53, the compression nut I55 is in threaded connection with the inner wall of the valve seat 4 and compresses the spring I54, and the step, so that the cryogenic medium entering the air inlet channel 22 enters the filler I52 through the valve cavity and the air guide hole A, the cold shrinkage of the filler I52 is further reduced, and the filler I52 is further deformed through the pretightening force of the spring I54 to realize reliable sealing. The compression spring I54 enables the whole packing component I5 to have pretightening force, the cold flow of the packing I52 is reduced at low temperature, and the packing I52 is further deformed under the action of the pretightening force, so that the low-temperature sealing reliability is ensured.

Further, a step B is arranged on the inner wall of the valve body 1, a shaft shoulder A is arranged on the outer wall of the valve seat 4, a flooding plug seal assembly I is arranged between the valve seat 4 and the valve body 1, the flooding plug seal assembly I comprises a check ring I6, a flooding plug seal I7 and a support ring 8 which are sequentially arranged from bottom to top, the check ring I6 is placed on the step B, the flooding plug seal I7 is placed on the check ring I6, the opening of the flooding plug seal I is downward, the support ring 8 is placed on the flooding plug seal I7, and the shaft shoulder A of the valve seat 4 is matched with the step B of the valve body 1 to clamp the flooding plug seal assembly I;

there is the clearance between disk seat 4 and the valve body 1, be provided with air guide hole B on the retaining ring I6 to let the cryrogenic medium that gets into in the inlet channel 22 get into through this clearance and air guide hole B the general stopper seals the opening of I7, thereby lets general stopper seal I7 further inflation realize reliable sealing.

Further, a stepped hole with a large upper part and a small lower part is arranged on the cylinder body 11, the stepped hole penetrates through the piston 131 and is provided with a large hole and a small hole, and the piston 131, the sealing cavity I and the sealing cavity II are all positioned in the large hole of the stepped hole;

a step C is arranged on the inner wall of the cylinder body 11;

valve rod 3 with be provided with packing assembly II 12 between cylinder body 11, packing assembly II 12 is located in the aperture of shoulder hole to this packing assembly II 12 includes from supreme supporting shoe II, filler II, dog II, spring II and the gland nut II that sets gradually down, and wherein the lower extreme of supporting shoe II is the horizontal plane and the upper end is the V type that the opening is up, shelve on the shoulder C for the lower extreme of supporting shoe II, filler II also is V type structure and filler II places on the supporting shoe II, the upper end of dog II is the horizontal plane and the lower extreme also is the V type, the lower extreme of dog II is pressed on filler II, spring II presses the upper end of dog II, gland nut II and the inner wall threaded connection of cylinder body 11 compress tightly spring II, be provided with air guide hole C on dog II to let the control gas that gets into seal chamber II pass through the aperture of shoulder hole with the air guide hole C of dog II gets into fill out And II is fed, so that the II filler is shrunk and is further deformed through the pretightening force of the II spring to realize reliable sealing.

Further, a step D is arranged on the inner wall of the piston 131, a packing component III is arranged between the upper end of the valve rod 3 and the piston 131, the packing component III comprises a supporting block III, a packing III, a stop block III, a spring III and a compression nut III which are sequentially arranged from bottom to top, wherein the lower end of the supporting block III is a horizontal plane, the upper end of the supporting block III is in an inverted V shape, the lower end of the supporting block III is placed on the step D, the packing III is also in an inverted V-shaped structure, the packing III is placed on the supporting block III, the upper end of the stop block III is a horizontal plane, the lower end of the stop block III is pressed on the packing III, the spring III is pressed on the upper end of the stop block III, the compression nut III is in threaded connection with the valve seat 4 and compresses the spring III, and the step D and the supporting block III are respectively provided with air guide holes D which are communicated with, so that control gas entering the sealing cavity II enters the filler III through the large hole of the stepped hole and the air guide hole D, and the filler III is shrunk and further deformed through the pretightening force of the spring II to realize reliable sealing.

The sealing principle of the packing component III and the packing component II 12 is the same as that of the packing component I5, the sizes of the packing components can be different, and the packing components are designed according to installation sizes.

Further, the valve rod locking device further comprises a locking plug screw and a locking nut, wherein an external thread of the locking plug screw is connected with the large hole of the stepped hole, an internal thread of the locking nut is connected with the upper end of the valve rod 3 and pressed on the compression nut III to fix the upper end of the valve rod 3, and air flow through holes are distributed in the locking plug screw to enable control air to enter the large hole of the stepped hole to push the piston 131 and the valve rod 3 to move downwards.

Further, the piston assembly 13 comprises a piston 131 and a flooding plug assembly ii, and the flooding plug assembly ii is sleeved on the piston 131 to realize sealing between the piston 131 and the cylinder 11;

a shaft shoulder B is arranged on the piston 131;

the flooding plug seal assembly II comprises an elastic retainer ring II 134, a flooding plug seal II 132 and a retainer ring II 133 which are sleeved on the piston 131, the elastic retainer ring II 134 is matched with the shaft shoulder B to clamp the flooding plug seal II 132 and the retainer ring II 133, the retainer ring II 133 is positioned between the elastic retainer ring II 134 and the flooding plug seal II 132, and an opening of the flooding plug seal II 132 faces the retainer ring II 133;

the retainer ring II 133 is provided with an air guide hole E130, so that control air entering the inner cavity of the cylinder body 11 enters the opening of the flooding plug seal II 132 through the air guide hole E130, and the flooding plug seal II 132 is further expanded to realize reliable sealing.

The flooding plug seal assemblies II are arranged in two groups, and are symmetrically arranged above and below the shaft shoulder B.

Further, an annular positioning groove is formed in the bottom of the cylinder body 11, an annular positioning boss is arranged at the top end of the valve seat 4, the annular positioning boss extends into the annular positioning groove to achieve positioning of the valve seat 4, and a sealing gasket I9 is further installed in the annular positioning groove to achieve static sealing of the cylinder body 11 and the valve seat 4; be provided with the step E that is used for accepting disk seat 4 on the valve body 1, be provided with sealed II 10 of filling up on the step E, realize the static seal of valve body 1 and disk seat 4, sealed II 10 of filling up makes the inner chamber that disk seat 4 and cylinder body 11 constitute sealed relatively, ensures not to have a large amount of steam to get into, and at ultra-low temperature during operation, valve rod 3 can not be because of the frozen fish tail motion face of steam in the motion process.

Further, the cylinder body 11 comprises a cylinder barrel and a piston cover 17 arranged on the top of the cylinder barrel, a sealing gasket III 16 is arranged between the cylinder barrel and the piston cover 17 to realize static sealing between the cylinder barrel and the piston cover 17, the electromagnetic directional valve 19 is arranged on the piston cover 17, and a heat insulation cushion block 18 is arranged between the electromagnetic directional valve 19 and the piston cover 17. .

The valve body 1 is a rotary body shell part, the air inlet channel 22 is close to the air outlet channel 23, the air inlet channel 22 is perpendicular to the air outlet channel 23, and the outlet end of the air inlet channel 22 and the inlet end of the air outlet channel 23 are partially overlapped, so that the air inlet channel 22 and the air outlet channel 23 can be directly communicated.

The valve seat 4 is a step-shaped shaft part, the outer wall of the valve seat 4 is provided with a first conical surface with a large upper part and a small lower part as an installation guide surface, the flooding plug seal I7 can be conveniently installed on the valve seat 4 from bottom to top, the flooding plug seal I7 is ensured not to be damaged during installation, and the cone angle theta value of the first conical surface is preferably 15-25 degrees. The valve seat 4 is located the top of inlet channel 22 and outlet channel 23, and through installing general stopper subassembly I between valve seat 4 and valve body 1, general stopper subassembly I constitutes from pressure boost seal structure, realizes radial seal, realizes axial direction's redundant seal through installing sealed the II 10 of packing between valve seat 4 and valve body 1. The combined design of the radial self-pressurization sealing structure and the axial redundant sealing ensures that the valve body 1 and the valve seat 4 are sealed reliably.

The flooding plug seal I7 and the flooding plug seal II 132 are Y-shaped lip-shaped self-pressurization low-temperature-resistant sealing elements with built-in metal springs, the lip-shaped outer cover is provided with an opening, and after initial installation, under the action of the pre-tightening force of the built-in springs, the lip-shaped outer cover has a certain deformation amount to realize initial sealing; when a cryogenic medium or control gas pressure exists, the cryogenic medium or control gas enters the opening of the lip-shaped outer cover through the gas guide hole, and the lip-shaped outer cover is further tensioned under the action of the cryogenic medium or control gas pressure, so that further reliable sealing is realized. The self-pressurization sealing structure can realize low-temperature sealing, and a little leakage can be caused under the abnormal condition; the axial seal is the last line of defense, if the front edge realizes the seal, the line of defense is of a redundant design, if the front edge has medium leakage or a little medium leakage, the line of defense can ensure reliable seal without low-temperature medium leakage.

The locating surface of the upper end of the inner hole of the valve body 1 and the valve seat 4 form a locating structure of the valve body 1 and the valve seat 4, radial locating of the valve body 1 and the valve seat 4 is achieved, and the preferred roughness of the locating surface of the valve body 1 and the valve seat 4 is Ra (0.4-0.8). Among the sealed face that has the sealing member on valve body 1 and the valve seat 4, the sealed face roughness that is used for realizing radial direction sealed is preferably Ra (0.1 ~ 0.2), is used for realizing that the sealed face roughness of axial direction is preferably Ra (0.2 ~ 0.4).

The upper end and the lower end of the cylinder body 11 are respectively provided with a flange which is respectively connected with the valve body 1 and the piston cover 17; the cylinder body 11 is pressed on the valve seat 4 and is connected and locked with the valve body 1 through a screw, a flat pad and an elastic pad, the upper end of an inner hole of the valve body 1 is in clearance fit with the valve seat 4 to form a positioning structure I, an annular positioning groove and an annular positioning boss are designed in the radial direction of installation of the cylinder body 11 and the valve seat 4 to form a positioning structure II, and the radial positioning of the cylinder body 11, the valve seat 4 and the valve body 1 is realized.

The inner cavity of the cylinder 1 of the invention is designed with a second conical surface with a big top and a small bottom as a cylinder installation guide surface at the inlet for installing the piston assembly 13, the second conical surface can be guided and led in when the piston assembly 13 is installed, the flooding plug seal II 132 with compression is prevented from being damaged, and the value of the cone angle theta of the second conical surface is preferably 15-25 degrees.

The roughness of the sealing surface of the cylinder 11, the piston 131 and the valve rod 3 where the sealing member moves is preferably Ra (0.1-0.2), the roughness of the guide surface is preferably Ra (0.4-0.8), and the guide surface and the sealing surface are in arc transition.

The control gas inlet 24 of the electromagnetic directional valve 19 is filled with control gas, when the electromagnetic directional valve is electrified, the port B of the electromagnetic directional valve 19 is communicated, the sealing cavity II of the cylinder body 11 is filled with the control gas through the control gas port B, the piston 131 moves upwards to drive the valve rod 3 to move, the outlet end of the gas inlet channel 22 is opened, and therefore the stop valve is opened; when the electromagnetic directional valve 19 is powered off, the port A of the electromagnetic directional valve 19 is conducted, control gas is filled into the sealing cavity I through the control gas port A on the piston cover 17, the control gas port B discharges the control gas, the piston 131 moves downwards to drive the valve rod 3 and the sealing ring 2 to move downwards, the outlet end of the gas inlet channel 22 is closed, and therefore the stop valve is closed. The present invention uses high pressure control gas acting on the piston 131 to close the shut off valve so that the valve outlet can withstand high reverse impact pressures.

The installation process of the invention is as follows:

1) counting and cleaning all parts; wherein, the degreasing treatment is carried out on a valve body 1, a sealing ring 2, a valve rod 3, a valve seat 4, a packing component I5, a check ring I6, a flooding plug seal I7, a combined supporting ring 8 and a sealing gasket I9;

2) the sealing ring 2 is arranged in the valve rod 3, and the sealing ring 2 is tightly pressed and locked by a flat gasket, an elastic gasket and a nut;

3) the valve rod 3 provided with the sealing ring 2 is arranged in the valve seat 4, and a packing component I5 is arranged;

4) sequentially installing a check ring I6, a flooding plug seal I7, a combined support ring 8 and a sealing gasket I9 into the valve body 1, wherein the opening of the flooding plug seal I7 faces to the medium direction;

5) butting the cylinder body 11, the sealing gasket II 10, the valve body 1 and the valve seat 4 into a positioning groove, and locking by using a screw, a flat gasket and an elastic gasket;

6) a packing assembly II 12 is arranged in the cylinder body 11, and the opening direction of the V-shaped packing faces to the sealing cavity;

7) two groups of flooding plug seals II 132, check rings II 133 and spring check rings 134 are sequentially arranged on the piston 131 from the upper direction and the lower direction respectively, and the opening installation directions of the flooding plug seals II 132 are opposite;

8) slightly pressing the piston assembly 13 with the flooding plug sealing assembly II into the cylinder body 11;

9) packing assembly II 12 is arranged in the piston 131; the locking nut locks the valve rod 3, and the locking screw plug is arranged on the piston 131;

10) mounting a sealing gasket III 16 and a piston cover 17, and locking by using a flat gasket, an elastic gasket and a screw;

11) installing a heat insulation cushion block 18 and a two-position five-way electromagnetic valve 19 on a piston cover 17; the electromagnetic directional valve 19 and the cylinder are connected by an a-port connection pipe 20 and a B-port connection pipe 21, respectively.

It is to be understood that the foregoing are many different embodiments or examples of the different features of the present embodiments. Specific examples of components and arrangements are described below to simplify the illustrative embodiments. These are, of course, merely examples and are not intended to limit the embodiments, and for example, device dimensions are not limited to the ranges or values disclosed, but may depend on processing conditions and/or desired properties of the device. Moreover, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed interposing the first and second features, such that the first and second features may not be in direct contact, although the various features may be drawn arbitrarily to varying proportions for simplicity and clarity of illustration.

Spatially relative terms, such as "under," "below," "lower," "above," "upper," and the like, may be used herein to describe one element or feature's relationship to another element or feature(s) as illustrated in the figures. These spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The device may be oriented in different ways (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. An ultralow temperature electromagnetic pneumatic stop valve is characterized by comprising a valve body, a valve rod, a valve seat, a cylinder and an electromagnetic directional valve, wherein,

the valve seat is mounted on the valve body and located in the valve cavity;

2. The ultralow temperature electromagnetic pneumatic stop valve according to claim 1, characterized in that the inner wall of the valve seat is provided with a step A, a packing assembly I is arranged between the valve rod and the valve seat, the packing assembly I comprises a support block I, a packing I, a stop block I, a spring I and a compression nut I which are sequentially arranged from bottom to top, wherein the lower end of the support block I is a horizontal plane, the upper end of the support block I is an inverted V-shaped, the lower end of the support block I is placed on the step A, the packing I is also in an inverted V-shaped structure, the packing I is placed on the support block I, the upper end of the stop block I is a horizontal plane, the lower end of the stop block I is also inverted V-shaped, the lower end of the stop block I is pressed on the packing I, the spring I is pressed on the upper end of the stop block I, the compression nut I is in threaded connection with the inner, step A and supporting shoe I are last to be provided with air guide hole A of intercommunication respectively to let the cryrogenic medium that gets into in the inlet channel pass through valve pocket and air guide hole A get into filler I, thereby let I shrinkage of filler and the pretightning force through spring I make filler I further warp and realize reliable sealing.

3. An ultralow-temperature electromagnetic pneumatic stop valve as claimed in claim 1, characterized in that the inner wall of the valve body is provided with a step B, the outer wall of the valve seat is provided with a shaft shoulder A, a flooding plug assembly I is arranged between the valve seat and the valve body, the flooding plug assembly I comprises a check ring I, a flooding plug assembly I and a support ring which are sequentially arranged from bottom to top, the check ring I is placed on the step B, the flooding plug assembly I is placed on the check ring I with an opening facing downwards, the support ring is placed on the flooding plug assembly I, and the shaft shoulder A of the valve seat is matched with the step B of the valve body to clamp the flooding plug assembly I;

4. An ultralow-temperature electromagnetic pneumatic stop valve as in claim 1, wherein the cylinder body is provided with a stepped hole with a large top and a small bottom, the stepped hole penetrates through the piston and is provided with a large hole and a small hole, and the piston, the sealing cavity I and the sealing cavity II are all positioned in the large hole of the stepped hole;

a step C is arranged on the inner wall of the cylinder body;

5. The ultralow temperature electromagnetic pneumatic stop valve according to claim 4, wherein the inner wall of the piston is provided with a step D, a packing assembly III is arranged between the upper end of the valve rod and the piston, the packing assembly III comprises a supporting block III, a packing III, a stop block III, a spring III and a compression nut III which are sequentially arranged from bottom to top, wherein the lower end of the supporting block III is a horizontal plane, the upper end of the supporting block III is an inverted V-shaped, the lower end of the supporting block III is placed on the step D, the packing III is also in an inverted V-shaped structure, the packing III is placed on the supporting block III, the upper end of the stop block III is a horizontal plane, the lower end of the stop block III is also in an inverted V-shaped, the lower end of the stop block III is pressed on the packing III, the spring III is pressed on the upper end of the stop block III, and the compression nut III is in threaded connection, and the step D and the supporting block III are respectively provided with an air guide hole D which is communicated with each other, so that control air entering the sealing cavity II can pass through the large hole of the stepped hole and the air guide hole D enters the filler III, and the filler III is shrunk and further deforms through the pretightening force of the spring II to realize reliable sealing.

6. An ultra-low temperature electromagnetic pneumatic stop valve as claimed in claim 5, further comprising a locking plug screw and a locking nut, wherein the external thread of the locking plug screw is connected with the large hole of the stepped hole, the internal thread of the locking nut is connected with the upper end of the valve rod and the locking nut presses on the compression nut III for fixing the upper end of the valve rod, and the locking plug screw is distributed with air flow through holes for allowing control air to enter the large hole of the stepped hole to push the piston and the valve rod to move downwards.

7. The ultralow-temperature electromagnetic pneumatic stop valve according to claim 1, characterized in that the piston assembly comprises a piston and a flooding plug assembly II, wherein the flooding plug assembly II is sleeved on the piston for realizing the sealing of the piston and the cylinder;

a shaft shoulder B is arranged on the piston;

8. An ultralow temperature electromagnetism pneumatic stop valve according to claim 1, characterized in that, the bottom of cylinder body is provided with annular positioning groove, the top of disk seat is provided with annular location boss, annular location boss stretches into in the annular positioning groove, realizes the location of disk seat, and still install sealed I in the annular positioning groove.

9. An ultralow temperature electromagnetic pneumatic stop valve as in claim 1, wherein said valve body is provided with a step E for receiving the valve seat, and said step E is provided with a sealing gasket II.

10. An ultra-low temperature electromagnetic pneumatic stop valve as claimed in claim 1, characterized in that the cylinder body comprises a cylinder barrel and a piston cover mounted on the top of the cylinder barrel, a sealing gasket III is mounted between the cylinder barrel and the piston cover, the electromagnetic directional valve is mounted on the piston cover, and a heat insulation cushion block is mounted between the electromagnetic directional valve and the piston cover.