CN113531127A

CN113531127A - Ultralow-temperature pneumatic regulating valve

Info

Publication number: CN113531127A
Application number: CN202110766804.2A
Authority: CN
Inventors: 王涛; 滕磊军; 张振旭; 孙拥军; 董聿森; 白宇; 张斐
Original assignee: Beijing Aerospace Rate Mechanical & Electrical Engineering Co ltd; Beijing Institute of Aerospace Testing Technology
Current assignee: Beijing Aerospace Rate Mechanical & Electrical Engineering Co ltd; Beijing Institute of Aerospace Testing Technology
Priority date: 2021-05-20
Filing date: 2021-07-07
Publication date: 2021-10-22
Anticipated expiration: 2041-07-07
Also published as: CN216078311U; CN113531127B

Abstract

An ultra-low temperature pneumatic regulating valve, comprising a valve body, a valve cover, a valve stem and a valve seat, one end of the valve stem is connected with a pneumatic actuator, the other end is placed in the valve seat through a valve cover, and a valve stem is provided inside the valve cover for the valve stem to pass through. The inner cavity of the cylinder is provided with a guiding mechanism on the valve stem located in the inner cavity of the cylinder, and the guiding mechanism is arranged at the port near one end of the valve seat in the inner cavity of the cylinder. By arranging a copper ring between the valve stem and the inner cavity of the cylinder, and setting the copper ring close to the valve seat end, the smoothness of the valve stem movement is improved, the radial runout of the valve stem is prevented, the adjustment accuracy is high, and the work can be performed in liquid hydrogen. warm zone.

Description

Ultralow-temperature pneumatic regulating valve

Technical Field

The invention relates to the technical field of regulating valves, in particular to an ultralow-temperature pneumatic regulating valve for a liquid hydrogen temperature zone.

Background

The regulating valve is also called a control valve, and in the field of industrial automation process control, the final control element for changing the process parameters of medium flow, pressure, temperature, liquid level and the like by power operation through receiving the control signal output by a regulating control unit. Generally consisting of an actuator and a valve. The regulating valve can be divided into: the pneumatic control valve is characterized by comprising a manual regulating valve, a pneumatic regulating valve, an electric regulating valve and a hydraulic regulating valve, wherein the pneumatic regulating valve takes compressed air as a power source, the electric regulating valve takes electricity as a power source, and the hydraulic regulating valve takes pressure of liquid media (such as oil and the like) as power.

The ultralow temperature pneumatic regulating valve is the most common regulating equipment in large-scale low-temperature refrigeration equipment and is the most important actuating mechanism for realizing the regulation of thermal parameters such as low-temperature working medium flow, pressure and the like in process control.

In the existing low-temperature regulating valve, one end of a valve rod is connected with a pneumatic actuating mechanism, the other end of the valve rod penetrates through a valve cover and is arranged in a valve seat, and the pneumatic actuating mechanism realizes flow regulation of the valve seat by controlling the displacement of the valve rod. In the process, the total length of the valve rod is large, so that the precision in reciprocating motion cannot be guaranteed, and large radial run-out is easy to generate, so that the motion precision of the valve core is influenced, and the valve core is not suitable for being used in a working environment of a liquid hydrogen temperature region. In addition, the existing low-temperature regulating valve also has the problem of poor sealing performance.

The present invention has been made in view of this situation.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide an ultralow-temperature pneumatic regulating valve, which aims to enhance the reciprocating motion precision of a valve rod and solve the problem that the valve rod is easy to generate larger radial run-out to influence the motion precision of a valve core due to large length of the valve rod in the working process of the current ultralow-temperature pneumatic regulating valve.

In order to solve the technical problems, the invention adopts the technical scheme that:

the utility model provides an ultra-low temperature pneumatic control valve, includes valve body, valve gap, valve rod and disk seat, and valve rod one end links to each other with pneumatic actuator, and the other end passes the valve gap and arranges the disk seat in, and the inside cylinder inner chamber that supplies the valve rod to pass through that is provided with of valve gap is located and is equipped with guiding mechanism on the valve rod of cylinder inner chamber part, and guiding mechanism sets up the port department that is close to disk seat one end in the cylinder inner chamber.

Furthermore, a valve rod positioned in the cylindrical inner cavity part is provided with a first radial bulge, and the first radial bulge is flush with a port at one end of the cylindrical inner cavity close to the valve seat; a limiting block is fixed at a position, close to the first radial protrusion, of the valve rod located in the inner cavity of the cylinder, a copper ring used for guiding the valve rod is sleeved between the first radial protrusion and the limiting block, and the first radial protrusion, the limiting block and the copper ring form a guiding mechanism.

Further, the valve rod comprises an upper valve rod and a lower valve rod, the upper valve rod is in threaded connection with the lower valve rod, and the first radial protrusion and the limiting block are arranged on the lower valve rod;

the inner diameter of the copper ring is the same as the diameter of the lower valve rod, and the outer diameter of the copper ring is the same as the diameter of the cylindrical inner cavity.

Further, the port of the cylindrical inner cavity extends towards the valve seat to form a thin-wall protruding structure, and the first radial bulge is flush with the port of the thin-wall protruding structure close to the end of the valve seat.

Furthermore, an adjusting valve core is arranged at one end of the lower valve rod, which extends into the valve seat, the maximum diameter of the adjusting valve core is the same as the inner diameter of the valve seat, a groove is arranged at the joint of the adjusting valve core and the lower valve rod, and the diameter of the groove is the same as that of the lower valve rod;

one end of the lower valve rod, which is close to the valve seat, is provided with a second radial bulge close to the end, the end of the lower valve rod extends into the groove, the second radial bulge is attached to the adjusting valve core, and the second radial bulge is connected with the adjusting valve core through a screw.

Further, a lower sealing seat is arranged between the second radial bulge and the adjusting valve core, and a gap is reserved between the end head of the lower valve rod and the bottom of the groove;

a boss with the diameter smaller than that of the adjusting valve core is arranged on the end face, close to the second radial bulge, of the adjusting valve core, and a groove matched with the boss is formed in the lower sealing seat;

the diameter of the lower sealing seat is larger than the inner diameter of the valve seat.

Furthermore, an upper sealing seat is arranged at the port of the valve cover, which is far away from one end of the valve body;

a filling cavity is arranged between one end, far away from the valve body, of the upper sealing seat and the upper valve rod, and filling materials are arranged in the filling cavity.

Furthermore, a packing gland is arranged at one end of the valve cover, which is far away from the valve body, and the packing gland is connected to the valve cover through a screw;

the packing gland extends into the filling cavity and is pressed on the packing.

Further, a valve seat pressing block is arranged between the valve cover and the valve seat.

Further, be provided with first O type circle between gland and the valve rod, be provided with second O type circle and first gasket between last seal receptacle and the valve gap, be provided with third O type circle between last seal receptacle and the valve rod, be provided with the second gasket between valve gap and the valve body, be provided with the third gasket between disk seat and the valve body.

After adopting the technical scheme, compared with the prior art, the invention has the following beneficial effects:

1. the copper ring is arranged between the valve rod and the cylindrical inner cavity and is arranged at the bottom end of the cylindrical inner cavity, so that guidance of the valve rod is enhanced, and reciprocating motion of the valve rod has high smoothness.

2. The thin-wall protruding structure is arranged at the port of the cylindrical inner cavity, so that the guiding position of the valve rod is as low as possible and is as close to the adjusting valve core as possible, the reciprocating motion precision of the adjusting valve core is further improved, the action of the adjusting valve is more accurate, the valve rod is prevented from generating radial jumping in the axial moving process, and the adjusting precision is high.

3. Through setting up filler material, first O type circle, second O type circle, third O type circle, first gasket, second gasket and third gasket, guarantee the leakproofness of device, through setting up seal receptacle and lower seal receptacle in addition, make the sealed effect of device further strengthen. The ultralow-temperature pneumatic regulating valve has high regulating precision and excellent sealing performance, and can work in a liquid hydrogen temperature range (-253 ℃).

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood, the present invention may be implemented in accordance with the content of the description, and in order to make the above and other objects, features, and advantages of the present invention more clearly understood, the following specific examples are described in detail with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention, are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without limiting the invention to the right. It is obvious that the drawings in the following description are only some embodiments, and that for a person skilled in the art, other drawings can be derived from them without inventive effort. In the drawings:

FIG. 1 is a schematic diagram of the overall structure of an ultra-low temperature pneumatic control valve in the embodiment of the invention;

FIG. 2 is an enlarged schematic view of the structure at A in FIG. 1 according to an embodiment of the present invention;

FIG. 3 is an enlarged schematic view of the embodiment of the present invention at B in FIG. 1;

fig. 4 is an enlarged schematic structural diagram at C in fig. 1 according to an embodiment of the present invention.

Number 1, packing gland in the attached figure; 2. a filler; 3. an upper seal seat; 4. an upper valve stem; 5. a valve cover; 6. a lower valve stem; 7. a copper ring; 8. a valve seat pressing block; 9. a valve body; 10. a first inlet/outlet; 11. a second inlet/outlet; 12. a second radial projection; 13. adjusting the valve core; 14. a valve seat; 15. a lower seal seat; 16. a limiting block; 17. a first radial projection; 18. a second O-ring; 19. a first gasket; 20. a third O-ring; 21. a third gasket; 22. thin-walled projection structures.

It should be noted that the drawings and the description are not intended to limit the scope of the inventive concept in any way, but to illustrate it by a person skilled in the art with reference to specific embodiments.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and the following embodiments are used for illustrating the present invention and are not intended to limit the scope of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

As shown in fig. 1 to 4, the invention relates to an ultra-low temperature pneumatic regulating valve, which comprises a valve body 9, a valve cover 5 and a valve rod, wherein the valve cover 5 is fixed on the valve body 9 through screws, the valve body 9 is provided with a first inlet/outlet 10 and a second inlet/outlet 11, a valve seat 14 is arranged at the communication position of the first inlet/outlet 10 and the inner end of the second inlet/outlet 11, one end of the valve rod is connected with a pneumatic actuator, the other end of the valve rod penetrates through the valve cover 5 and is arranged in the valve seat 14, and the pneumatic actuator controls the displacement of the valve rod to realize the flow regulation of the valve seat 14.

In this embodiment, the passages of the first port 10 and the second port 11 are arc-shaped passages. The upper end of the valve rod is connected with a pneumatic actuator, the lower end of the valve rod penetrates through the valve cover 5 and is arranged in the valve seat 14, the lower end of the valve rod is provided with an adjusting valve core 13, the adjusting valve core 13 can be matched with the valve seat 14, and the pneumatic actuator can control the valve rod to reciprocate in the valve cover 5, so that the adjusting valve core 13 is driven to reciprocate to realize flow adjustment of the valve seat 14.

Preferably, a cylindrical inner cavity for the valve rod to pass through is arranged in the valve cover 5, a guide mechanism is arranged on the valve rod positioned in the cylindrical inner cavity, and the guide mechanism is arranged at a port close to one end of the valve seat 14 in the cylindrical inner cavity. The valve rod positioned in the cylindrical inner cavity part is provided with a first radial bulge 17, and when the regulating valve is closed, the first radial bulge 17 is flush with the port of the cylindrical inner cavity close to one end of the valve seat 14; a limiting block 16 is fixed at the position, close to the first radial protrusion 17, of the valve rod positioned in the inner cavity of the cylinder, and a copper ring 7 used for guiding the valve rod is sleeved between the first radial protrusion 17 and the limiting block 16. The first radial protrusion 17, the stop block 16 and the copper ring 7 form a guide mechanism. The valve rod is provided with the guide mechanism, so that the moving stability of the valve rod and the adjusting valve core 13 in the cylindrical inner cavity is enhanced.

Example one

Preferably, a cylindrical inner cavity for the valve rod to pass through is formed in the valve cover 5, a first radial protrusion 17 is arranged on the valve rod positioned in the cylindrical inner cavity, and when the regulating valve is closed, the first radial protrusion 17 is flush with a port of the cylindrical inner cavity, which is close to one end of the valve seat 14; a limiting block 16 is welded at the position, close to the first radial protrusion 17, of the valve rod located in the inner cavity of the cylinder, and a copper ring 7 used for guiding the valve rod is sleeved between the first radial protrusion 17 and the limiting block 16. The copper ring 7 for guiding is arranged on the valve rod, so that the moving stability of the valve rod and the adjusting valve core 13 in the cylindrical inner cavity is enhanced.

Preferably, in this embodiment, through setting up first radial bulge 17 and stopper 16, fix a position copper ring 7 on the valve rod, through setting up first radial bulge 17 at the cylinder inner chamber lower extreme, when the governing valve is complete when closed, first radial bulge 17 flushes with cylinder inner chamber lower terminal surface, make copper ring 7 that is used for leading the valve rod be close to disk seat 14 as far as possible, the position of valve rod direction is low as far as, the reinforcing is to the direction effect of adjusting case 13, thereby the smoothness of reinforcing adjusting case 13 reciprocating motion, can guarantee adjusting case 13 reciprocating motion's precision like this, prevent to adjust case 13 because of the longer great runout of production of valve rod.

In this embodiment, the valve rod includes upper valve rod 4 and lower valve rod 6, and upper end and the pneumatic actuator of upper valve rod 4 link to each other, and threaded connection between lower extreme and the lower valve rod 6. The first radial protrusion 17 and the stopper 16 are both provided on the lower stem 6, thereby fixing the copper ring 7 on the lower stem 6. The inner diameter of the copper ring 7 is the same as the diameter of the lower valve rod 6, and the outer diameter of the copper ring 7 is the same as the diameter of the cylindrical inner cavity.

In this embodiment, a valve seat pressing block 8 is disposed between the valve cover 5 and the valve seat 14, and the valve cover 5 fixes the valve seat 14 through the valve seat pressing block 8. Preferably, the valve seat pressing block 8 is of a cylindrical structure and is arranged coaxially with the valve seat 14, and a plurality of openings are formed in the valve seat pressing block 8 for liquid to flow through. The upper end of the valve seat pressing block 8 is abutted against the valve cover 5, and the lower end is pressed on the valve seat 14, so that the valve seat 14 is fixed in the valve body 9.

As shown in fig. 2, in the present embodiment, an upper sealing seat 3 is disposed at a port at the upper end of the valve cap 5; the lower end of the upper sealing seat 3 is matched with the upper valve rod 4, the upper end of the upper sealing seat is expanded to form a filling cavity, and the filling cavity is internally provided with the filler 2. Preferably, the filler 2 used in this embodiment is Polytetrafluoroethylene (PTFE).

As shown in fig. 1, in this embodiment, a packing gland 1 is disposed on one end of the valve cover 5 away from the valve body 9, the packing gland 1 is screwed to the valve cover 5, and the packing gland 1 extends into the filling cavity and is pressed on the packing 2. In this embodiment, the packing gland 1 compresses the packing 2 and the upper seal base 3 against the upper end of the valve cover 5 to form an upper seal structure.

In this embodiment, an adjusting valve core 13 is arranged at one end of the lower valve rod 6 extending into the valve seat 14, and the diameter of the adjusting valve core 13 is the same as the inner diameter of the valve seat 14. The diameter of the regulating valve core 13 is matched with the valve seat 14, and the flow of the valve seat 14 is regulated.

The lower end of the lower valve rod 6 is provided with a second radial bulge 12, and an adjusting valve core 13 is installed on the second radial bulge 12 through a screw.

Preferably, the diameter of the regulating valve core 13 is gradually reduced from top to bottom, so that the regulating valve core 13 is easier to enter the valve seat 14 in the reciprocating process, and the smoothness of the movement of the regulating valve core 13 is improved.

Preferably, in this embodiment, a first O-ring is disposed between the packing gland 1 and the valve rod, a second O-ring 18 and a first gasket 19 are disposed between the upper sealing seat 3 and the valve cover 5, a third O-ring 20 is disposed between the upper sealing seat 3 and the valve rod, a second gasket is disposed between the valve cover 5 and the valve body 9, and a third gasket 21 is disposed between the valve seat 14 and the valve body 9.

Preferably, in this embodiment, the upper seal seat 3, the first O-ring, the second O-ring 18, the third O-ring 20, the first gasket 19, the second gasket, and the third gasket 21 are made of a non-metallic soft material, so as to enhance the sealing performance of the regulating valve.

Preferably, in the present embodiment, the medium flows into the valve body 9 from the first port 10 and flows out of the valve body 9 from the second port 11.

Example two

As shown in fig. 1 to 4, the invention relates to an ultra-low temperature pneumatic regulating valve, which comprises a valve body 9, a valve cover 5 and a valve rod, wherein the valve cover 5 is fixed on the valve body 9 through screws, the valve body 9 is provided with a first inlet/outlet 10 and a second inlet/outlet 11, a valve seat 14 is arranged at the communication position of the first inlet/outlet 10 and the inner end of the second inlet/outlet 11, one end of the valve rod is connected with a pneumatic actuator, the other end of the valve rod penetrates through the valve cover 5 and is arranged in the valve seat 14, and the pneumatic actuator controls the displacement of the valve rod to realize the flow regulation of the valve seat 14. The passages of the first port 10 and the second port 11 are arc-shaped passages. The upper end of the valve rod is connected with a pneumatic actuator, the lower end of the valve rod penetrates through the valve cover 5 and is arranged in the valve seat 14, the lower end of the valve rod is provided with an adjusting valve core 13, the adjusting valve core 13 can be matched with the valve seat 14, and the pneumatic actuator can control the valve rod to reciprocate in the valve cover 5, so that the adjusting valve core 13 is driven to reciprocate to realize flow adjustment of the valve seat 14.

Preferably, a cylindrical inner cavity for the valve rod to pass through is formed in the valve cover 5, a first radial protrusion 17 is arranged on the valve rod positioned in the cylindrical inner cavity, and when the regulating valve is closed, the first radial protrusion 17 is flush with a port of the cylindrical inner cavity, which is close to one end of the valve seat 14; a limiting block 16 is welded at the position, close to the first radial protrusion 17, of the valve rod located in the inner cavity of the cylinder, and a copper ring 7 used for guiding the valve rod is sleeved between the first radial protrusion 17 and the limiting block 16. The copper ring 7 for guiding is arranged on the valve rod, so that the moving stability of the valve rod and the adjusting valve core 13 in the cylindrical inner cavity is enhanced. Through setting up first radial bulge 17 and stopper 16, fix a position copper ring 7 on the valve rod, through setting up first radial bulge 17 at the cylinder inner chamber lower extreme, when the governing valve is complete when closed, first radial bulge 17 flushes with cylinder inner chamber lower extreme face, make the copper ring 7 that is used for leading the valve rod be close to disk seat 14 as far as possible, the position of valve rod direction is as low as possible, the reinforcing is to the direction effect of adjusting case 13, thereby strengthen adjusting case 13 reciprocating motion's ride comfort, can guarantee adjusting case 13 reciprocating motion's precision like this, prevent to adjust case 13 because of the longer great runout of production of valve rod.

In the present embodiment, as shown in fig. 3, the lower port of the cylindrical inner cavity extends toward the valve seat 14 to form a thin-walled projection structure 22, and the first radial protrusion 17 is flush with the lower port of the thin-walled projection structure 22. So that the copper ring 7 for guiding the valve stem is further close to the valve seat 14, which can further improve the precision of the reciprocating motion of the regulator valve element 13.

In this embodiment, the valve rod includes upper valve rod 4 and lower valve rod 6, and upper end and the pneumatic actuator of upper valve rod 4 link to each other, and threaded connection between lower extreme and the lower valve rod 6. The first radial protrusion 17 and the stopper 16 are both provided on the lower stem 6, thereby fixing the copper ring 7 on the lower stem 6. The inner diameter of the copper ring 7 is the same as the diameter of the lower valve rod 6, and the outer diameter of the copper ring 7 is the same as the diameter of the cylindrical inner cavity. A valve seat pressing block 8 is arranged between the valve cover 5 and the valve seat 14, and the valve cover 5 fixes the valve seat 14 through the valve seat pressing block 8. Preferably, the valve seat pressing block 8 is of a cylindrical structure and is arranged coaxially with the valve seat 14, and a plurality of openings are formed in the valve seat pressing block 8 for liquid to flow through. The upper end of the valve seat pressing block 8 is abutted against the valve cover 5, and the lower end is pressed on the valve seat 14, so that the valve seat 14 is fixed in the valve body 9.

Preferably, the diameter of the adjusting valve core 13 is gradually reduced from top to bottom, so that the adjusting valve core 13 is easier to enter the valve seat 14 in the reciprocating motion process, the smoothness of the movement of the adjusting valve core 13 is improved, and the major diameter of the adjusting valve core 13 is the same as the inner diameter of the valve seat 14.

Preferably, in the present embodiment, the medium flows into the valve body 9 from the second port 11 and flows out of the valve body 9 from the first port 10.

EXAMPLE III

Preferably, a cylindrical inner cavity for the valve rod to pass through is formed in the valve cover 5, a first radial protrusion 17 is arranged on the valve rod positioned in the cylindrical inner cavity, and when the regulating valve is closed, the first radial protrusion 17 is flush with a port of the cylindrical inner cavity, which is close to one end of the valve seat 14; a limiting block 16 is welded at the position, close to the first radial protrusion 17, of the valve rod located in the inner cavity of the cylinder, and a copper ring 7 used for guiding the valve rod is sleeved between the first radial protrusion 17 and the limiting block 16. Through set up the copper ring 7 that is used for the direction on the valve rod, the stability of reinforcing valve rod and adjusting valve core 13 motion in the cylinder inner chamber is through setting up first radial arch 17 and stopper 16, fixes a position copper ring 7 on the valve rod.

In the present embodiment, as shown in fig. 3, the lower port of the cylindrical inner cavity extends toward the valve seat 14 to form a thin-walled projection structure 22, and the first radial protrusion 17 is flush with the lower port of the thin-walled projection structure 22. Therefore, the copper ring 7 used for guiding the valve rod is further close to the valve seat 14, the reciprocating motion precision of the adjusting valve core 13 can be further improved, and the adjusting valve core 13 is prevented from generating large radial run-out due to long valve rod in the reciprocating motion process of the adjusting valve core 13.

As shown in fig. 4, in this embodiment, an adjusting valve core 13 is disposed at one end of the lower valve rod 6, which extends into the valve seat 14, the diameter of the adjusting valve core 13 is the same as the inner diameter of the valve seat 14, and a groove is disposed at a joint of the adjusting valve core 13 and the lower valve rod 6, and the diameter of the groove is the same as the diameter of the lower valve rod 6.

The lower end of the lower valve rod 6 is provided with a second radial bulge 12 close to the end, the end of the lower valve rod 6 extends into the groove, the lower end face of the second radial bulge 12 is attached to the upper end face of the adjusting valve core 13, and the second radial bulge 12 is fixedly connected with the adjusting valve core 13 through screws. A lower sealing seat 15 is arranged between the second radial bulge 12 and the regulating valve core 13, a boss with the diameter smaller than that of the regulating valve core 13 is arranged on the end face of the regulating valve core 13 close to the second radial bulge 12, a groove matched with the boss is arranged on the lower sealing seat 15, and the diameter of the lower sealing seat 15 is larger than the inner diameter of the valve seat 14. In this embodiment, the lower end surface of the lower sealing seat 15 is attached to the gap where the regulating valve element 13 and the valve seat 14 are fitted, so as to enhance the sealing effect between the first inlet/outlet 10 and the second inlet/outlet 11.

In this embodiment, a gap is reserved between the lower end of the lower valve rod 6 and the bottom of the groove. The pressing force of the second radial protrusion 12 and the adjusting valve core 13 on the lower seal seat 15 can be adjusted by adjusting the screw pretightening force connected between the second radial protrusion 12 and the adjusting valve core 13. A mortise matching mode is adopted between the lower sealing seat 15 and the adjusting valve core 13, sealing between the lower valve rod 6 and the adjusting valve core 13 is realized under the action of a screw pretightening force, and leakage of a medium from a gap between the lower valve rod 6 and the adjusting valve core 13 is prevented.

Preferably, in this embodiment, the upper seal seat 3, the lower seal seat 15, the first O-ring, the second O-ring 18, the third O-ring 20, the first gasket 19, the second gasket, and the third gasket 21 are all made of a non-metallic soft material, so as to enhance the sealing performance of the regulating valve.

The above description is only for the preferred embodiment of the present invention, and not intended to limit the present invention in any way, and although the present invention has been disclosed by the preferred embodiment, it is not intended to limit the present invention, and those skilled in the art can make various changes and modifications to the equivalent embodiment without departing from the scope of the present invention.

Claims

1. The utility model provides an ultra-low temperature pneumatic control valve, includes valve body (9), valve gap (5), valve rod and disk seat (14), and valve rod one end links to each other with pneumatic actuator, and the other end passes valve gap (5) and arranges disk seat (14) in, and its characterized in that, valve gap (5) inside is provided with the cylinder inner chamber that supplies the valve rod to pass through, is located to be equipped with guiding mechanism on the valve rod of cylinder inner chamber part, and guiding mechanism sets up the port department that is close to disk seat (14) one end in the cylinder inner chamber.

2. Ultra-low temperature pneumatic regulating valve according to claim 1, characterized in that the valve stem located in the cylindrical inner cavity portion is provided with a first radial projection (17), the first radial projection (17) being flush with the port of the cylindrical inner cavity near the end of the valve seat (14); a limiting block (16) is fixed at a position, close to a first radial protrusion (17), of a valve rod located in the inner cavity of the cylinder, a copper ring (7) used for guiding the valve rod is sleeved between the first radial protrusion (17) and the limiting block (16), and the first radial protrusion (17), the limiting block (16) and the copper ring (7) form a guiding mechanism.

3. An ultra-low temperature pneumatic regulating valve according to claim 2, characterized in that the valve rod comprises an upper valve rod (4) and a lower valve rod (6), the upper valve rod (4) and the lower valve rod (6) are in threaded connection, and the first radial protrusion (17) and the limiting block (16) are both arranged on the lower valve rod (6);

the inner diameter of the copper ring (7) is the same as the diameter of the lower valve rod (6), and the outer diameter of the copper ring (7) is the same as the diameter of the cylindrical inner cavity.

4. Ultra-low temperature pneumatic regulating valve according to any one of claims 1 to 3, characterized in that the cylindrical inner chamber port extends towards the valve seat (14) forming a thin-walled projecting structure (22), the first radial projection (17) being flush with the port of the thin-walled projecting structure (22) near the end of the valve seat (14).

5. An ultralow temperature pneumatic regulating valve according to claim 4, wherein one end of the lower valve rod (6) extending into the valve seat (14) is provided with a regulating valve core (13), the maximum diameter of the regulating valve core (13) is the same as the inner diameter of the valve seat (14), a groove is arranged at the joint of the regulating valve core (13) and the lower valve rod (6), and the diameter of the groove is the same as that of the lower valve rod (6); one end of the lower valve rod (6) close to the valve seat (14) is provided with a second radial bulge (12) close to the end, the end of the lower valve rod (6) extends into the groove, the second radial bulge (12) is attached to the adjusting valve core (13), and the second radial bulge (12) is connected with the adjusting valve core (13) through screws.

6. The ultra-low temperature pneumatic regulating valve as claimed in claim 5, characterized in that a lower sealing seat (15) is arranged between the second radial bulge (12) and the regulating valve core (13), and a gap is reserved between the end of the lower valve rod (6) and the bottom of the groove;

a boss with the diameter smaller than that of the adjusting valve core (13) is arranged on the end face, close to the second radial bulge (12), of the adjusting valve core (13), and a groove matched with the boss is formed in the lower sealing seat (15);

the diameter of the lower sealing seat (15) is larger than the inner diameter of the valve seat (14).

7. An ultra-low temperature pneumatic adjusting valve as claimed in claim 6, characterized in that the valve cover (5) is provided with an upper sealing seat (3) at the port far away from one end of the valve body (9); a filling cavity is arranged between one end, far away from the valve body (9), of the upper sealing seat (3) and the upper valve rod (4), and a filler (2) is arranged in the filling cavity.

8. An ultralow temperature pneumatic regulating valve according to claim 7, wherein a packing gland (1) is arranged at one end of the valve cover (5) far away from the valve body (9), and the packing gland (1) is screwed on the valve cover (5); the packing gland (1) extends into the filling cavity and is pressed on the packing (2).

9. Ultra-low temperature pneumatic regulating valve according to any one of claims 1 to 3 and 5 to 8, characterized in that a valve seat pressing block (8) is provided between the valve cover (5) and the valve seat (14).

10. An ultra-low temperature pneumatic regulating valve according to claim 9, characterized in that a first O-ring is arranged between the packing gland (1) and the valve rod, a second O-ring (18) and a first gasket (19) are arranged between the upper sealing seat (3) and the valve cover (5), a third O-ring (20) is arranged between the upper sealing seat (3) and the valve rod, a second gasket is arranged between the valve cover (5) and the valve body (9), and a third gasket (21) is arranged between the valve seat (14) and the valve body (9).