High-pressure pneumatic stop valve

Abstract

The invention discloses a high-pressure pneumatic stop valve which comprises a main valve and a pneumatic executing mechanism. The main valve comprises a shell, a valve rod and a jacket nut, a cavity is formed in the main valve, a cutting edge sealing face is arranged in the middle of the shell, and medium inlets and outlets connected with an external pipeline are formed in the left side and the right side of the shell. The pneumatic executing mechanism comprises a valve seat, a pneumatic control port and a spring, and the pneumatic control port is connected with the upper portion of the shell and used for being connected with an external control air source; the valve rod is a step-shaped shaft part and penetrates through a center hole of an inner cavity of the shell, the upper end of the valve rod is connected with the valve seat, and the lower end of the valve rod is matched with the jacket nut. A conical sealing face is arranged on the lower portion of the valve rod, the conical sealing face can make contact with the cutting edge sealing face of the shell to form cut-off sealing, and the valve rod, the valve seat and the shell jointly define a pneumatic cavity. The spring is arranged in the pneumatic cavity, and the two ends of the spring abut against the valve seat and the shell respectively. The valve rod and valve element integration mode is adopted to replace traditional threaded connection, and the reliability and stability of parts under the high-pressure working condition are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of valves, in particular to a high-pressure pneumatic stop valve. BACKGROUND

[0002] In the gas delivery pipeline of a rocket engine, a pneumatic stop valve is used to control the opening and closing of a nitrogen or helium pipeline, and the pressure can reach 36.5 MPa. The technical points of the high-pressure pneumatic stop valve are that the whole valve needs to be stably sealed and flexibly opened under high-pressure working conditions. In the existing high-pressure pneumatic stop valve, the valve stem and the valve core are usually connected by threads. Under high-pressure working conditions, stress concentration is prone to occur at the threaded connection, and fatigue cracks are prone to occur at the threaded connection under the impact of gas and vibration load, thereby causing connection failure. On this basis, a high-pressure pneumatic stop valve is proposed. SUMMARY

[0003] 1. Technical problem to be solved by the application: The present application provides a high-pressure pneumatic stop valve to solve the technical problems in the background art.

[0004] 2. Technical scheme: In order to achieve the above-mentioned purpose, the technical scheme of the present application is as follows: A high-pressure pneumatic stop valve comprises a main valve and a pneumatic actuator. The main valve comprises a shell, a valve stem and a sleeve nut. The shell has a cavity inside, and a blade sealing surface is arranged in the middle of the shell. The left and right sides of the shell are provided with medium inlets and outlets connected with external pipelines. The pneumatic actuator comprises a valve seat, a pneumatic control port and a spring. The pneumatic control port is connected with the upper part of the shell and is used to connect with an external control gas source. The valve stem is a stepped shaft part, which passes through the center hole of the shell cavity, and the upper end is connected with the valve seat, and the lower end is matched with the sleeve nut. The lower part of the valve stem is provided with a conical sealing surface, which can be in contact with the blade sealing surface of the shell to form a stop sealing, and the valve stem, the valve seat and the shell jointly form a pneumatic cavity. The spring is arranged in the pneumatic cavity, and the two ends of the spring are respectively in abutment with the valve seat and the shell.

[0005] Preferably, in the natural state, the spring pushes the valve seat against the pneumatic control port through the pre-tightening force, and drives the valve stem to move upward to make the conical sealing surface press against the blade sealing surface, so that the valve is in a normally closed state. When the driving force formed on the upper surface of the valve seat by the control gas entering the pneumatic cavity from the pneumatic control port is greater than the sum of the pre-tightening force of the spring, the resistance of the medium outlet side and the friction force of the valve stem movement (i.e. ), the valve stem moves downward, the conical sealing surface is separated from the blade sealing surface, and the medium flow passage is opened.

[0006] Preferably, the upper part of the shell is provided with a first threaded interface, and the pneumatic control port is connected and fixed with the first threaded interface through internal threads; an annular groove is arranged on the inner hole wall of the pneumatic control port, and a first sealing ring is arranged in the annular groove, and dynamic sealing is realized between the pneumatic control port and the valve seat through the first sealing ring.

[0007] Preferably, the lower part of the shell is provided with a second threaded interface, and the sleeve nut is connected and fixed with the second threaded interface through internal threads, for axial positioning of the valve stem and realization of end face sealing.

[0008] Preferably, an annular groove is arranged on the outer peripheral wall of the lower part of the valve stem, and a third sealing ring is arranged in the annular groove, for enhancing the sealing performance of the cooperation part of the valve stem and the sleeve nut.

[0009] Preferably, the spring is a compression spring, and is sleeved on the upper part of the valve stem; the upper end of the spring abuts against the inner annular groove of the valve seat, and the lower end abuts against the inner wall of the shell.

[0010] Preferably, a fourth sealing ring is arranged between the cavity of the shell and the valve stem and the sleeve nut, and the fourth sealing ring is a static sealing structure, for blocking the leakage of the medium in the cavity.

[0011] Preferably, a second sealing ring is arranged between the middle part of the valve stem and the center hole wall of the inner cavity of the shell, and the second sealing ring cooperates with the valve stem to form a piston part, for separating the cavity in the shell.

[0012] 3. Beneficial effects: Compared with the prior art, the technical scheme provided by the present application has the following beneficial effects: The valve stem and the valve core are designed as a single, integrated stepped shaft part, replacing the traditional threaded connection mode; the integrated part simultaneously has the movement function of a piston and the sealing function of a valve core; in addition, the valve stem is provided with multiple sealing rings from the upper part to the lower part, which are combined in a dynamic and static sealing mode. This design realizes flexible opening and reliable sealing of the pneumatic stop valve under high-pressure working conditions, significantly improves the overall reliability, and simultaneously reduces the volume, weight and cost; The pneumatic stop valve provided by the present application only needs to remove the sleeve nut and the pneumatic control port to take out the internal valve stem part for maintenance or replacement, without the need to remove the entire valve from the pipeline, which greatly facilitates the maintenance behavior. BRIEF DESCRIPTION OF DRAWINGS

[0013] Fig. 1 is a structural schematic view of the pneumatic stop valve provided by the present application; Fig. 2 is a structural schematic view of the valve stem of the pneumatic stop valve provided by the present application; Fig. 3is a structural schematic view of a housing of a pneumatic stop valve provided by the present application.

[0014] Reference signs: 100: housing; 110: valve stem; 120: sleeve nut; 130: pneumatic control port; 140: valve seat; 150: spring.

[0015] 200: first sealing ring; 210: second sealing ring; 220: third sealing ring; 230: fourth sealing ring.

[0016] 300: pneumatic cavity; 310: first cavity; 320: second cavity.

[0017] 410: valve stem base; 420: conical sealing surface.

[0018] 510: first threaded interface; 520: second threaded interface; 530: medium inlet; 540: medium outlet. DETAILED DESCRIPTION

[0019] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings, in which several embodiments of the present application are given. However, the present application can be realized in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0020] With reference to Figs. 1-3 The present embodiment provides a high-pressure pneumatic stop valve, which comprises a main valve and a pneumatic actuator. The main valve comprises a housing 100, a valve stem 110 and a sleeve nut 120. The housing 100 has a cavity inside, and a blade sealing surface is arranged in the middle of the housing 100. Medium inlets and outlets are arranged on the left and right sides of the housing 100 for connecting with external pipelines. The pneumatic actuator comprises a valve seat 140, a pneumatic control port 130 and a spring 150. The pneumatic control port 130 is connected with the upper part of the housing 100 for connecting with an external control gas source. The valve stem 110 is a stepped shaft part, which passes through the central hole of the inner cavity of the housing 100, and the upper end is connected with the valve seat 140, and the lower end is matched with the sleeve nut 120. A conical sealing surface 420 is arranged on the lower part of the valve stem 110, which can be in contact with the blade sealing surface of the housing 100 to form a stop sealing. The valve stem 110, the valve seat 140 and the housing 100 jointly enclose a pneumatic cavity 300. The spring 150 is arranged in the pneumatic cavity 300, and the two ends of the spring 150 are respectively in abutment with the valve seat 140 and the housing 100.

[0021] In the preferred embodiment, the spring 150 pushes the valve seat 140 against the pneumatic control port 130 by pre-tightening force, and drives the valve stem 110 to move upward so that the conical sealing surface 420 is pressed against the blade sealing surface, and the valve is in the normally closed state; when the control gas enters the pneumatic control port 130, and the driving force formed on the upper surface of the valve seat 140 is greater than the sum of the spring pre-tightening force, the medium outlet side resistance and the valve stem movement friction (i.e. ), the valve stem 110 moves downward, the conical sealing surface 420 is separated from the blade sealing surface, and the medium flow passage is opened.

[0022] In the preferred embodiment, the upper part of the shell 100 is provided with a first threaded interface 510, and the pneumatic control port 130 is connected and fixed with the first threaded interface 510 through internal threads; an annular groove is arranged on the inner hole wall of the pneumatic control port 130, and a first sealing ring 200 is installed in the annular groove, and the dynamic sealing between the pneumatic control port 130 and the valve seat 140 is realized through the first sealing ring 200.

[0023] In the preferred embodiment, the lower part of the shell 100 is provided with a second threaded interface 520, and the outer sleeve nut 120 is connected and fixed with the second threaded interface 520 through internal threads, which is used for axial positioning of the valve stem 110 and realizes end face sealing.

[0024] In the preferred embodiment, an annular groove is arranged on the outer peripheral wall of the lower part of the valve stem 110, and a third sealing ring 220 is installed in the annular groove, which is used to enhance the sealing performance of the cooperation part between the valve stem 110 and the outer sleeve nut 120.

[0025] In the preferred embodiment, the spring 150 is a compression spring, and is sleeved on the upper part of the valve stem 110; the upper end of the spring 150 abuts against the inner annular groove of the valve seat 140, and the lower end abuts against the inner wall of the shell 100.

[0026] In the preferred embodiment, a fourth sealing ring 230 is arranged between the cavity of the shell 100 and the valve stem 110 and the outer sleeve nut 120, and the fourth sealing ring 230 is a static sealing structure, which is used to block the leakage of the medium in the cavity.

[0027] In the preferred embodiment, a second sealing ring 210 is arranged between the middle part of the valve stem 110 and the central hole wall of the inner cavity of the shell 100, and the second sealing ring 210 cooperates with the valve stem 110 to form a piston part, which is used to separate the cavity in the shell 100.

[0028] The working process of the present application is as follows: In the initial state, the pre-tightening force of the spring 150 pushes the valve seat 140 upward against the lower end surface of the pneumatic control port 130, and also moves the valve stem 110 upward, so that the lower conical valve core head is tightly pressed against the cutting edge sealing surface of the housing 100, and the pneumatic stop valve is in the closed state.

[0029] When the control gas with a certain pressure is introduced into the pneumatic control port 130, a driving force perpendicular to the upper surface of the valve seat 140 is formed when the gas enters the pneumatic cavity 300, and the valve stem 110 moves upward under the action of the driving force. When the valve stem 110 and the housing 100 are opened, the first cavity 310 and the second cavity 320 are communicated, and the medium flow path is opened.

[0030] When the pneumatic stop valve is discharged, the gas pressure of the pneumatic control port 130 is withdrawn, the valve stem 110 moves upward under the action of the spring force until the valve is closed and sealed. At this time, the spring 150 is gradually reset from the working state to the pre-tightening state, and the sum of the frictional forces of the first sealing ring 200, the second sealing ring 210 and the third sealing ring 220 needs to be overcome, the medium flow path is cut off, and the valve is closed.

[0031] The above-described embodiments only express certain embodiments of the present application, which are described in detail and specifically, but should not be understood as limiting the scope of the present application; it should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which belong to the protection scope of the present application; therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A high pressure pneumatic globe valve characterized by, The main valve and the pneumatic actuator are included; The main valve includes a shell (100), a valve stem (110) and a sleeve nut (120), the shell (100) has a cavity inside, and a blade sealing surface is arranged in the middle of the shell (100), and medium inlet and outlet ports are arranged on the left and right sides of the shell (100) to be connected with external pipelines; The pneumatic actuator includes a valve seat (140), a pneumatic control port (130) and a spring (150), the pneumatic control port (130) is connected with the upper part of the shell (100) to be connected with an external control gas source, the valve stem (110) is a stepped shaft part, passes through the central hole of the inner cavity of the shell (100), and the upper end is connected with the valve seat (140) and the lower end is matched with the sleeve nut (120), a conical sealing surface (420) is arranged on the lower part of the valve stem (110), the conical sealing surface (420) can be in contact with the blade sealing surface of the shell (100) to form a cut-off seal, and the valve stem (110), the valve seat (140) and the shell (100) jointly enclose a pneumatic cavity (300), and the spring (150) is arranged in the pneumatic cavity (300) and abuts against the valve seat (140) and the shell (100) at both ends.

2. A high pressure pneumatic globe valve according to claim 1, wherein In a natural state, the spring (150) pushes the valve seat (140) to abut against the pneumatic control port (130) through a pre-tightening force, drives the valve stem (110) to move upwards to make the conical sealing surface (420) be pressed against the blade sealing surface, and the valve is in a normally closed state; when the control gas enters the pneumatic cavity (300) from the pneumatic control port (130) and the driving force formed on the upper surface of the valve seat (140) is greater than the sum of the spring pre-tightening force, the medium outlet side resistance and the valve stem movement friction, the valve stem (110) moves downwards, the conical sealing surface (420) is separated from the blade sealing surface, and the medium flow channel is opened.

3. A high pressure pneumatic globe valve according to claim 1, wherein, A first threaded interface (510) is arranged on the upper part of the shell (100), the pneumatic control port (130) is connected and fixed with the first threaded interface (510) through internal threads, an annular groove is arranged on the inner hole wall of the pneumatic control port (130), a first sealing ring (200) is arranged in the annular groove, and dynamic sealing is realized between the pneumatic control port (130) and the valve seat (140) through the first sealing ring (200).

4. A high pressure pneumatic globe valve according to claim 1, wherein, A second threaded interface (520) is arranged on the lower part of the shell (100), the sleeve nut (120) is connected and fixed with the second threaded interface (520) through internal threads, is used for axially positioning the valve stem (110), and end face sealing is realized.

5. A high pressure pneumatic globe valve according to claim 1, wherein, An annular groove is arranged on the outer peripheral wall of the lower part of the valve stem (110), and a third sealing ring (220) is arranged in the annular groove.

6. A high pressure pneumatic globe valve according to claim 1, wherein, The spring (150) is a compression spring and is sleeved on the upper part of the valve stem (110), the upper end of the spring (150) abuts against the inner annular groove of the valve seat (140), and the lower end abuts against the inner wall of the shell (100).

7. A high pressure pneumatic globe valve according to claim 1, wherein A fourth sealing ring (230) is arranged between the cavity of the shell (100) and the valve stem (110) and the sleeve nut (120), and the fourth sealing ring (230) is a static sealing structure.

8. A high pressure pneumatic globe valve according to claim 1, characterized in that, The second sealing ring (210) is arranged between the middle part of the valve rod (110) and the wall of the central hole of the inner cavity of the shell (100), and the second sealing ring (210) cooperates with the valve rod (110) to form a piston part for separating the cavity in the shell (100).

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