Pneumatic control valve for cryogenic liquid

Abstract

The utility model discloses a pneumatic control valve for cryogenic liquid, which comprises a valve body, a flow channel is arranged in the valve body, a lengthened valve pipe is arranged at the top of the valve body, a valve rod penetrates through the lengthened valve pipe, the top end of the lengthened valve pipe is sealed by a valve cover, a pneumatic actuating mechanism is arranged above the valve cover, and the upper end of the valve rod upwards penetrates through the valve cover and then is connected with the pneumatic actuating mechanism. A valve seat and a valve core are arranged in a flow channel of the valve body, the valve core is connected with the lower end of a valve rod, the valve rod is formed by connecting an upper valve rod and a lower valve rod, the lower valve rod is a hollow rod, a sealing sliding block is arranged at the lower end of the lower valve rod, the valve core is connected with the sealing sliding block, a sealing ring is sleeved on the sealing sliding block, a heat resistance sleeve is arranged in the lengthened valve pipe, and a double-layer corrugated pipe is arranged in the heat resistance sleeve. The lower end of the double-layer corrugated pipe is connected with the lower valve rod, the upper end of the double-layer corrugated pipe is connected with the corrugated pipe seat, the corrugated pipe seat is installed in a top end opening of the lengthened valve pipe, the upper valve rod penetrates through the corrugated pipe seat, and the upper guide heat insulation sleeve is installed on the corrugated pipe seat. The pneumatic control valve is suitable for a pipeline for conveying cryogenic liquid.

Description

Technical Field

[0001] This utility model relates to the field of valves, specifically to a pneumatic regulating valve for cryogenic liquids. Background Technology

[0002] Liquid hydrogen, due to its environmental friendliness and high energy density, has gained increasing attention as a new energy source in recent years, and is widely used in aerospace rocket fuel, energy storage systems, and the manufacture of superconducting materials. As a cryogenic liquid, liquid hydrogen operates at a temperature of -253℃. When ordinary pneumatic control valves are used in liquid hydrogen pipelines, the extremely low temperature of liquid hydrogen makes the sealing surfaces of these valves prone to deformation and failure, leading to valve leaks. Therefore, there is an urgent need for a pneumatic control valve specifically designed for cryogenic liquids. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a pneumatic regulating valve for cryogenic liquids that is not prone to sealing failure and leakage.

[0004] To solve the above problems, the technical solution adopted by this utility model is as follows: a pneumatic regulating valve for cryogenic liquids, comprising: a valve body, a flow channel for the cryogenic liquid to flow through the valve body, an extended valve tube at the top of the valve body, the lower end of the extended valve tube being connected to the top of the valve body, a valve stem passing through the extended valve tube, the top end of the extended valve tube being closed by a valve cover, a pneumatic actuator above the valve cover, the upper end of the valve stem passing upward through the valve cover and connected to the pneumatic actuator, the pneumatic actuator driving the valve stem to move up and down, a valve seat and a valve core in the flow channel of the valve body, the valve core being connected to the lower end of the valve stem, the valve core moving up and down under the drive of the valve stem, cooperating with the valve seat to regulate the flow rate of the flow channel, characterized in that: the valve stem is formed by an upper valve stem and a lower valve stem coaxially connected, the lower valve stem being hollow. The valve stem has a diameter smaller than that of the lower valve stem. A sealing slider is installed at the lower end of the lower valve stem. The valve core is located below the sealing slider and connected to it. A sealing ring is fitted on the sealing slider to seal the gap between it and the valve body. A heat-insulating sleeve is fitted on the outside of the valve stem in the extended valve tube. The heat-insulating sleeve is used to fill the gap between the valve stem and the extended valve tube. A double-layer bellows is fitted on the outside of the upper valve stem in the heat-insulating sleeve. The lower end of the double-layer bellows is connected to the top of the lower valve stem, and the upper end of the double-layer bellows is connected to the bellows seat. The bellows seat is installed in the top port of the extended valve tube. The upper valve stem passes through the bellows seat. An upper guide heat-insulating sleeve is installed on the bellows seat and fitted on the outside of the upper valve stem. The bellows seat and the upper guide heat-insulating sleeve are limited by the pressure of the valve cover.

[0005] Furthermore, in the aforementioned pneumatic regulating valve for cryogenic liquids, an insulation layer and a vacuum layer are wrapped around the outside of the valve body and the extended valve tube. The vacuum layer is located outside the insulation layer, the insulation layer is filled with insulation material, and the vacuum layer can be evacuated.

[0006] Furthermore, in the aforementioned pneumatic regulating valve for cryogenic liquids, the valve core and the sealing slider are connected by a pin, and a disc spring is provided between the valve core and the sealing slider, which axially presses the valve core, the sealing slider, and the pin together.

[0007] Furthermore, in the aforementioned pneumatic control valve for cryogenic liquids, the extended valve tube and valve body are integrally welded together.

[0008] Furthermore, in the aforementioned pneumatic regulating valve for cryogenic liquids, the sealing ring includes a spring-loaded sealing ring.

[0009] The advantages of this utility model are as follows: In the pneumatic regulating valve, the lower valve stem is set as a hollow stem, which can greatly reduce the outward transfer of cold energy from the cryogenic liquid, thereby reducing the impact of low temperature on the valve seal; in addition, since four sealing structures are added from bottom to top to prevent liquid leakage and heat leakage, the four sealing structures are: a sealing ring is set on the sealing slider, a heat-insulating sleeve is filled in the extended valve tube, a double-layer bellows is fitted on the outside of the upper valve stem, and a guide heat-insulating sleeve is fitted on the outside of the upper valve stem neck, so that the normal operation of the valve can be guaranteed. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of a pneumatic regulating valve for cryogenic liquids according to the present invention. Detailed Implementation

[0011] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings.

[0012] like Figure 1As shown, a pneumatic regulating valve for cryogenic liquids includes: a valve body 1, a flow channel 2 for the cryogenic liquid to flow through in the valve body 1, an extended valve tube 3 at the top of the valve body 1, the lower end of the extended valve tube 3 being connected to the top of the valve body 1, a valve stem 4 passing through the extended valve tube 3, the top end of the extended valve tube 3 being closed by a valve cover 5, a pneumatic actuator 6 above the valve cover 5, the upper end of the valve stem 4 passing upward through the valve cover 5 and being connected to the pneumatic actuator 6, the pneumatic actuator 6 being able to drive the valve stem 4 to move up and down, a valve seat 8 and a valve core 7 being provided in the flow channel 2 of the valve body 1, the valve core 7 being connected to the lower end of the valve stem 4, the valve core 7 moving up and down under the drive of the valve stem 4, and being able to cooperate with the valve seat 8 to regulate the flow rate of the flow channel 2, the valve stem 4 being formed by an upper valve stem 9 and a lower valve stem 10 coaxially connected, the lower valve stem 10 being a hollow stem, the diameter of the upper valve stem 9 being smaller than that of the lower valve stem 10, the lower valve stem 10 being... A sealing slider 11 is provided at the lower end of the valve body 1. The valve core 7 is located below the sealing slider 11 and connected to it. A sealing ring is fitted on the sealing slider 11 to seal the gap between it and the valve body 1. A heat-insulating sleeve 12 is provided in the extended valve tube 3 and fitted on the outside of the valve stem 4. The heat-insulating sleeve 12 is used to fill the gap between the valve stem 4 and the extended valve tube 3. A double-layer bellows 13 is provided in the heat-insulating sleeve 12 and fitted on the outside of the upper valve stem 9. The lower end of the double-layer bellows 13 is connected to the top of the lower valve stem 10, and the upper end of the double-layer bellows 13 is connected to the bellows seat 14. The bellows seat 14 is installed in the top port of the extended valve tube 3. The upper valve stem 9 passes through the bellows seat 14. An upper guide heat insulation sleeve 15 is installed on the bellows seat 14 and fitted on the outside of the upper valve stem 9. The bellows seat 14 and the upper guide heat insulation sleeve 15 are pressed and limited by the valve cover 5.

[0013] The hollow design of the lower valve stem 10 significantly reduces the outward transfer of cold energy from the cryogenic liquid, thereby reducing the impact of low temperature on the valve seal. In addition, four sealing structures are added from bottom to top to prevent liquid leakage and heat leakage. The four sealing structures are: a sealing ring on the sealing slider 11, a heat-insulating sleeve 12 filled in the extended valve tube 3, a double-layer bellows 13 fitted on the outside of the upper valve stem 9, and a guide heat-insulating sleeve 15 fitted on the outside of the neck of the upper valve stem 9, which ensures the normal operation of the valve.

[0014] In this embodiment, an insulation layer 16 and a vacuum layer 17 are wrapped around the outside of the valve body 1 and the extended valve pipe 3. The vacuum layer 17 is located outside the insulation layer 16. The insulation layer 16 is filled with insulation material, and the vacuum layer 17 can be evacuated. This arrangement can greatly reduce the low-temperature heat leakage value.

[0015] The valve core 7 and the sealing slider 11 are connected by a pin. A cotter pin is installed on one end of the pin, and a disc spring is provided between the valve core 7 and the sealing slider 11. The disc spring axially tightens the valve core 7, sealing slider 11, and pin together. Due to the installation gap between the valve core 7, sealing slider 11, and pin, the valve core 7 may loosen axially. The disc spring tightens the valve core 7, eliminating this looseness. The pin connection allows for quick assembly and disassembly, facilitating later maintenance. The extended valve tube 3 and valve body 1 are integrally welded, which reduces leakage. The sealing ring includes a spring-loaded sealing ring, which provides a better seal.

Claims

1. A pneumatic control valve for cryogenic liquids, comprising: The valve body contains a flow channel for cryogenic liquid. An extended valve tube is located at the top of the valve body, its lower end connected to the top of the valve body. A valve stem passes through the extended valve tube, and its top end is sealed by a valve cover. A pneumatic actuator is located above the valve cover. The upper end of the valve stem passes upward through the valve cover and connects to the pneumatic actuator, which drives the valve stem to move up and down. A valve seat and a valve core are located within the flow channel of the valve body. The valve core is connected to the lower end of the valve stem. The valve core, driven by the valve stem, moves up and down and cooperates with the valve seat to regulate the flow rate of the flow channel. The valve stem is characterized by being composed of an upper valve stem and a lower valve stem coaxially connected. The lower valve stem is hollow, and the diameter of the upper valve stem is smaller than that of the lower valve stem. The lower end of the lower valve stem... A sealing slider is provided, with the valve core located below and connected to it. A sealing ring is fitted on the sealing slider to seal the gap between it and the valve body. A heat-insulating sleeve is fitted on the outside of the valve stem in the extended valve tube to fill the gap between the valve stem and the extended valve tube. A double-layer bellows is fitted on the outside of the upper valve stem in the heat-insulating sleeve. The lower end of the double-layer bellows is connected to the top of the lower valve stem, and the upper end is connected to the bellows seat. The bellows seat is installed in the top port of the extended valve tube. The upper valve stem passes through the bellows seat. An upper guide heat-insulating sleeve is installed on the bellows seat and fitted on the outside of the upper valve stem. The bellows seat and the upper guide heat-insulating sleeve are limited by the pressure of the valve cover.

2. A pneumatic regulating valve for cryogenic liquids according to claim 1, characterized in that: An insulation layer and a vacuum layer are wrapped around the outside of the valve body and the extended valve pipe. The vacuum layer is located outside the insulation layer, which is filled with insulation material. The vacuum layer can be evacuated.

3. A pneumatic regulating valve for cryogenic liquids according to claim 1 or 2, characterized in that: The valve core and the sealing slider are connected by a pin, and a disc spring is provided between the valve core and the sealing slider to press the valve core, the sealing slider and the pin together axially.

4. A pneumatic regulating valve for cryogenic liquids according to claim 1 or 2, characterized in that: The extended valve tube and valve body are welded together as one piece.

5. A pneumatic regulating valve for cryogenic liquids according to claim 1 or 2, characterized in that: The sealing rings include spring-loaded sealing rings.

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