Buoyancy control valve for preventing high-pressure gas from flowing back

Abstract

The invention discloses a buoyancy control valve for preventing backflow of high-pressure gas, which comprises a valve body with an inlet / outlet A and an inlet / outlet B. A valve cover is fixed at the top of the valve body through a bolt, a valve sleeve is arranged in the valve body, a sealing ring is arranged between the valve cover and the valve sleeve, and a cone valve core capable of sliding up and down is arranged in the valve sleeve. A spring is arranged between the cone valve element and the valve cover, and a hollow floating ball is fixed to the bottom of the cone valve element through a connecting rod and located at the inlet-outlet B; the inlet / outlet B is used as an inlet of high-pressure gas and is connected to a pipeline in which high-pressure gas reverse flow possibly occurs; the valve body and the valve cover are provided with communicated pressure flow channels, and the pressure flow channels are used for transmitting fluid pressure of the inlet and outlet B to the pressure surface of the inner hole of the cone valve element; when the hollow floating ball is in the liquid, the buoyancy control valve is opened; and when the hollow floating ball is in the gas, the buoyancy control valve is switched off. Normal circulation of high-pressure liquid is not affected, and the problem of backflow of high-pressure gas caused by failure of liquid seal height reduction can be solved.

Description

Technical Field

[0001] The invention relates to a valve, in particular to a buoyancy control valve for preventing the backflow of high-pressure gas. Background Art

[0002] As a special equipment, the safety of pressure pipelines has always been a concern. When the design is used only as a hydraulic pipeline system connecting pressure vessels, under certain working conditions, the high-pressure gas in the pressure vessel flows back to the pipeline, which will have an adverse effect on the safety of the pipeline and the normal operation of the equipment. In order to achieve the discharge of a small amount of gas in the hydraulic pipeline and the isolation of a large amount of gas, the mainstream approach is to set an exhaust valve at the highest point of the hydraulic pipeline or at a place where gas is easily accumulated; and the isolation of a large amount of high-pressure gas is mainly achieved by the liquid level in the pressure vessel being higher than the position of the pressure pipeline, thereby forming a liquid seal to prevent the high-pressure gas medium from entering the pipeline. However, under certain extreme working conditions, the liquid seal may fail as the liquid level of the pressure vessel drops below the position of the pipeline, causing the high-pressure gas to flow back into the pressure pipeline. The hydraulic valve on the pressure pipeline cannot cut off the high-pressure gas, causing safety problems for the equipment and pipelines and expanding the scope of the accident. Summary of the invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a buoyancy control valve for preventing the backflow of high-pressure gas.

[0004] Technical solution: The buoyancy control valve for preventing the backflow of high-pressure gas described in the present invention comprises a valve body with an inlet and outlet A and an inlet and outlet B, a valve cover is fixed to the top of the valve body by bolts, a valve sleeve is arranged in the valve body, a sealing ring is arranged between the valve cover and the valve sleeve, a cone valve core that can slide up and down is arranged in the valve sleeve, a spring is arranged between the cone valve core and the valve cover, a hollow float is fixed to the bottom of the cone valve core by a connecting rod, and the hollow float is located at the inlet and outlet B; the inlet and outlet B are connected to the pipeline where the high-pressure gas may flow back as the inlet of the high-pressure gas; the valve body and the valve cover are provided with a communicating pressure flow channel, and the pressure flow channel is used to transmit the fluid pressure of the inlet and outlet B to the pressure surface of the inner hole of the cone valve core; when the hollow float is in the liquid, the buoyancy control valve is opened; when the hollow float is in the gas, the buoyancy control valve is closed.

[0005] Furthermore, the area of ​​the pressure surface of the inner hole of the cone valve core is S1, the area of ​​the bottom surface of the cone valve core is S3, and S3 is equal to S1.

[0006] Further, the inlet and outlet A are connected to an external hydraulic device, and the inlet and outlet B are connected to a pressure vessel;

[0007] When high-pressure liquid flows in from inlet and outlet A and flows out from inlet and outlet B, the pressure vessel is replenished with liquid. At this time, the pressure of inlet and outlet A is much greater than that of inlet and outlet B, and the cone valve core cone surface is subjected to the pressure F1 of the inlet and outlet A liquid, and the direction is vertically upward; through the pressure flow channel drainage, the pressure surface of the inner hole of the cone valve core is subjected to the pressure F2 of the inlet and outlet B liquid and the spring elastic force F3, and the sum of the gravity of the spring, cone valve core, connecting rod and hollow float is Fg, and the direction is vertically downward; the bottom surface of the cone valve core is subjected to the pressure F4 of the inlet and outlet B liquid and the buoyancy F5 of the hollow float, and the direction is vertically upward; S3 is equal to S1, so F4=F2 in any working condition; because the buoyancy F5 of the hollow float in the liquid is greater than F3+Fg, the pressure of inlet and outlet A is much greater than that of inlet and outlet B, and at this time F1+F4+F5>F2+F3+Fg, the cone valve core moves up, and the valve opens;

[0008] As the pressure in the pressure vessel increases, the liquid pressure at inlet and outlet B increases, and the pressure difference between inlet and outlet A and inlet and outlet B decreases until the pressures at inlet and outlet A and inlet and outlet B are equal. Then, the liquid replenishment to the pressure vessel stops. At this time, F1+F4+F5>F2+F3+Fg, and the cone valve core remains in the open position, and the valve is in the open state.

[0009] When the hydraulic circuit uses high-pressure liquid in the pressure vessel, the high-pressure liquid flows in from inlet and outlet B and flows out from inlet and outlet A. At this time, F4=F2, F5>F3+Fg, so F1+F4+F5>F2+F3+Fg, the cone valve core remains in the open position, the valve is opened, and the high-pressure liquid can flow in from inlet and outlet B and flow out from inlet and outlet A smoothly.

[0010] Furthermore, when extreme working conditions occur and the liquid level in the pressure vessel drops, causing the liquid seal to fail, high-pressure gas flows in from the inlet and outlet B. At this time, the buoyancy of the hollow float F5 is less than F3+Fg, and F4 and F2 are generated by the gas pressure, but F4=F2 is still maintained. The conical surface of the cone valve core is only affected by the residual pressure of the liquid, and F1 is extremely small. Therefore, F1+F4+F5<F2+F3+Fg. At this time, the cone valve core moves downward, and the valve is closed to prevent the high-pressure gas from flowing back into the pressure pipeline.

[0011] Furthermore, the hollow float is made of stainless steel, polyurethane or plastic.

[0012] Furthermore, the connection between the connecting rod and the hollow float and the cone valve core is welding or threaded connection.

[0013] Furthermore, the connecting rod is a hollow steel pipe or a plastic pipe.

[0014] Furthermore, the valve body and the valve cover are made of stainless steel and are formed by casting.

[0015] Furthermore, the valve sleeve is made of carbon steel, and the cone valve core and the spring are made of manganese silicon steel.

[0016] Furthermore, the bolts are high-strength bolts and are provided with anti-loosening washers.

[0017] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: the present invention utilizes the difference in buoyancy of the hollow float in liquid and gas to provide a buoyancy control mechanism for valve opening and closing, and can solve the problem of backflow of high-pressure gas in the pipeline caused by failure of liquid seal height drop without affecting the normal circulation of high-pressure liquid, thereby ensuring the safety of hydraulic pipelines and equipment and avoiding further expansion of the scope of accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic structural diagram of a buoyancy control valve for preventing backflow of high-pressure gas provided by an embodiment of the present invention;

[0019] Figure 2 Schematic diagram of the installation position of the buoyancy control valve in an embodiment of the present invention. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the accompanying drawings.

[0021] Attached Figures 1 to 2 The reference numerals in the figures are as follows:

[0022] 1. Inlet and outlet A; 2. Valve body; 3. Bolt; 4. Sealing ring; 5. Valve cover; 6. Spring; 7. Pressure channel; 8. Valve sleeve; 9. Cone valve core; 10. Inlet and outlet B; 11. Hollow float; 12. Connecting rod; 13. Pressure surface of the inner hole of the cone valve core; 14. Bottom surface of the cone valve core; 15. Cone surface of the cone valve core.

[0023] like Figure 1 As shown, the embodiment of the present invention is improved on the basis of the conical valve, and provides a buoyancy control valve for preventing the backflow of high-pressure gas, including a valve body 2 with an inlet and outlet A (marked as 1 in the figure) and an inlet and outlet B (marked as 10 in the figure), a valve cover 5 is fixed to the top of the valve body 2 by bolts 3, a valve sleeve 8 is arranged in the valve body 2, and a sealing ring 4 is arranged between the valve cover 5 and the valve sleeve 8 to prevent leakage of high-pressure liquid; a conical valve core 9 that can slide up and down is arranged in the valve sleeve 8; a spring 6 is arranged between the conical valve core 9 and the valve cover 5, and a hollow float 11 is fixed to the bottom of the conical valve core 9 by a connecting rod 12, and the hollow float 11 is located at the inlet and outlet B; a communicating pressure flow channel 7 is arranged on the valve body 2 and the valve cover 5, and the pressure flow channel 7 is used to transmit the fluid pressure of the inlet and outlet B to the pressure surface 13 of the inner hole of the conical valve core.

[0024] The valve body 2 and the valve cover 5 are made of stainless steel and are formed by casting.

[0025] Bolt 3 is a high-strength bolt and is equipped with an anti-loosening washer.

[0026] The valve sleeve 8 is made of carbon steel, which has the characteristics of high strength, good toughness and easy processing.

[0027] The cone valve core 9 and the spring 6 are made of manganese silicon steel, which has the advantages of good impact toughness and light weight, can effectively reduce its own weight, and facilitate the design and calculation of the size of the hollow float 11.

[0028] The hollow floating ball 11 is made of materials such as stainless steel, polyurethane, plastic, etc. to increase buoyancy and reduce its own gravity.

[0029] The connecting rod 12 is made of a hollow steel pipe or a plastic pipe to reduce the weight of the connecting rod 12 itself.

[0030] The connection between the connecting rod 12 and the hollow floating ball 11 and the cone valve core 9 is a hard connection such as welding or threaded connection.

[0031] The area of ​​the pressure surface 13 of the inner hole of the cone valve core is S1, the area of ​​the cone surface 15 of the cone valve core is S2, and the area of ​​the bottom surface 14 of the cone valve core is S3. The area relationship between the three is reasonably designed and calculated so that S3 is equal to S1. The inner diameter and buoyancy of the air float are calculated and designed, and a spring with appropriate elastic force is selected so that the buoyancy of the hollow float in the liquid is greater than the sum of the spring elastic force and the overall deadweight of the cone valve core with the connecting rod, float, and spring, while in the gas, the buoyancy of the hollow float is less than the sum of the spring elastic force and the overall deadweight of the cone valve core with the connecting rod, float, and spring.

[0032] Under the action of fluid pressure, the gravity of the cone valve core and the connecting rod float, the spring force, and the buoyancy generated by the float, the cone valve core moves up and down, thereby achieving the opening and closing function of the control valve. The displacement of the cone valve core is determined by the distance between the top surface of the cone valve core and the valve cover.

[0033] like Figure 2 As shown, the installation of the buoyancy control valve is directional. The pipeline that may have high-pressure gas backflow needs to be connected to the inlet and outlet B of the buoyancy control valve. The inlet and outlet B with the float can only be the inlet of high-pressure gas. The inlet and outlet of high-pressure liquid can be either inlet and outlet A or inlet and outlet B.

[0034] The specific working principle of the present invention is as follows:

[0035] Inlet and outlet A are connected to external hydraulic equipment, and inlet and outlet B are connected to pressure vessels.

[0036] When high-pressure liquid flows in from inlet and outlet A and flows out from inlet and outlet B, the pressure vessel is replenished with liquid. At this time, the pressure of inlet and outlet A is much greater than the pressure of inlet and outlet B, and the cone valve core cone surface 15 is subjected to the pressure F1 of the liquid in inlet and outlet A, and the direction is vertically upward; through the pressure flow channel 7, the pressure surface 13 of the inner hole of the cone valve core is subjected to the pressure F2 of the liquid inlet and outlet B and the elastic force F3 of the spring 6. The sum of the gravity of the spring 6, the cone valve core 9, the connecting rod 12 and the hollow floating ball 11 is Fg, and the direction is vertically downward; the bottom surface 14 of the cone valve core is subjected to the pressure F4 of the liquid inlet and outlet B and the buoyancy F5 of the hollow floating ball 11, and the direction is vertically upward; S3 is equal to S1, so F4=F2 in any working condition; because the buoyancy F5 of the hollow floating ball 11 in the liquid is greater than F3+Fg, the pressure of inlet and outlet A is much greater than the pressure of inlet and outlet B, and at this time F1+F4+F5>F2+F3+Fg, the cone valve core 9 moves up, and the valve opens; high-pressure liquid flows in from inlet and outlet A and flows out from inlet and outlet B, and the pressure vessel is replenished with liquid;

[0037] As the pressure in the pressure vessel increases, the liquid pressure at inlet and outlet B increases, and the pressure difference between inlet and outlet A and inlet and outlet B decreases until the pressures at inlet and outlet A and inlet and outlet B are equal, and the liquid replenishment to the pressure vessel stops. At this time, F1+F4+F5>F2+F3+Fg, and the cone valve core 9 remains in the open position, and the valve is in the open state;

[0038] When the hydraulic circuit uses high-pressure liquid in the pressure vessel, the high-pressure liquid flows in from the inlet and outlet B and flows out from the inlet and outlet A. At this time, F4=F2, F5>F3+Fg, so F1+F4+F5>F2+F3+Fg, the cone valve core 9 remains in the open position, the valve is opened, and the high-pressure liquid can flow in from the inlet and outlet B and flow out from the inlet and outlet A smoothly.

[0039] When extreme working conditions occur and the liquid level in the pressure vessel drops, causing the liquid seal to fail, high-pressure gas flows in from the inlet and outlet B. At this time, the buoyancy F5 of the hollow float 11 is less than F3+Fg, and F4 and F2 are generated by the gas pressure, but F4=F2 is still maintained. The cone surface 15 of the cone valve core is only affected by the residual pressure of the liquid, and F1 is extremely small. Therefore, F1+F4+F5<F2+F3+Fg. At this time, the cone valve core 9 moves downward and the valve is closed, preventing the high-pressure gas from flowing back into the pressure pipeline and preventing the scope of the accident from expanding.

Claims

1. A buoyancy control valve for preventing high-pressure gas from flowing back, comprising a valve body (2) having an inlet and outlet A (1) and an inlet and outlet B (10), a valve cover (5) being fixed to the top of the valve body (2) by bolts (3), a valve sleeve (8) being arranged in the valve body (2), a sealing ring (4) being arranged between the valve cover (5) and the valve sleeve (8), a cone valve core (9) being arranged in the valve sleeve (8) and being able to slide up and down, a spring (6) being arranged between the cone valve core (9) and the valve cover (5), characterized in that: A hollow float (11) is fixed to the bottom of the cone valve core (9) via a connecting rod (12), and the hollow float (11) is located at the inlet and outlet B (10); the inlet and outlet B (10) is used as an inlet for high-pressure gas and is connected to a pipeline where high-pressure gas backflow may occur; a communicating pressure flow channel (7) is provided on the valve body (2) and the valve cover (5), and the pressure flow channel (7) is used to transmit the fluid pressure of the inlet and outlet B (10) to the pressure surface (13) of the inner hole of the cone valve core; when the hollow float (11) is in the liquid, the buoyancy control valve is opened; when the hollow float (11) is in the gas, the buoyancy control valve is closed.

2. The buoyancy control valve for preventing the backflow of high-pressure gas according to claim 1, characterized in that: The area of ​​the pressure surface (13) of the inner hole of the cone valve core is S1, and the area of ​​the bottom surface (14) of the cone valve core is S3, and S3 is equal to S1.

3. The buoyancy control valve for preventing the backflow of high-pressure gas according to claim 2, characterized in that: The inlet and outlet A (1) is connected to an external hydraulic device, and the inlet and outlet B (10) is connected to a pressure vessel; When high-pressure liquid flows in from inlet and outlet A (1) and flows out from inlet and outlet B (10), the pressure vessel is replenished with liquid. At this time, the pressure of inlet and outlet A (1) is much greater than the pressure of inlet and outlet B (10). The conical surface (15) of the cone valve core is subjected to the pressure F1 of the liquid inlet and outlet A (1), and the direction is vertically upward. Through the pressure channel (7), the pressure surface (13) of the inner hole of the cone valve core is subjected to the pressure F2 of the liquid inlet and outlet B (10) and the elastic force F3 of the spring (6). The spring (6), the cone valve core (9), the connecting rod (12) and the hollow The sum of the weights of the float (11) is Fg, and the direction is vertically downward; the bottom surface (14) of the cone valve core is subjected to the pressure F4 of the liquid in the inlet and outlet B (10) and the buoyancy F5 of the hollow float (11), and the direction is vertically upward; S3 is equal to S1, so F4=F2 under any working condition; because the buoyancy F5 of the hollow float (11) in the liquid is greater than F3+Fg, the pressure of the inlet and outlet A (1) is much greater than the pressure of the inlet and outlet B (10), at this time F1+F4+F5>F2+F3+Fg, the cone valve core (9) moves upward, and the valve opens; As the pressure in the pressure container increases, the liquid pressure in the inlet and outlet B (10) increases, and the pressure difference between the inlet and outlet A (1) and the inlet and outlet B (10) decreases until the pressures in the inlet and outlet A (1) and the inlet and outlet B (10) are equal. Then, the liquid replenishment to the pressure container stops. At this time, F1+F4+F5>F2+F3+Fg is still satisfied, and the cone valve core (9) remains in the open position, and the valve is in the open state. When the hydraulic circuit uses the high-pressure liquid in the pressure vessel, the high-pressure liquid flows in from the inlet and outlet B (10) and flows out from the inlet and outlet A (1). At this time, F4=F2, F5>F3+Fg, so F1+F4+F5>F2+F3+Fg, the cone valve core (9) remains in the open position, the valve is opened, and the high-pressure liquid can smoothly flow in from the inlet and outlet B (10) and flow out from the inlet and outlet A (1).

4. The buoyancy control valve for preventing the backflow of high-pressure gas according to claim 3, characterized in that: When an extreme working condition occurs and the liquid level in the pressure vessel drops, causing the liquid seal to fail, high-pressure gas flows in from the inlet and outlet B (10). At this time, the buoyancy F5 of the hollow float (11) is less than F3+Fg, and F4 and F2 are generated by the gas pressure, but F4=F2 is still maintained. The cone surface (15) of the cone valve core is only affected by the residual pressure of the liquid, and F1 is extremely small. Therefore, F1+F4+F5<F2+F3+Fg. At this time, the cone valve core (9) moves downward and the valve is closed, preventing the high-pressure gas from flowing back into the pressure pipe.

5. The buoyancy control valve for preventing the backflow of high-pressure gas according to claim 1, characterized in that: The hollow floating ball (11) is made of stainless steel, polyurethane or plastic.

6. The buoyancy control valve for preventing the backflow of high-pressure gas according to claim 1, characterized in that: The connection between the connecting rod (12), the hollow floating ball (11) and the cone valve core (9) is by welding or threaded connection.

7. The buoyancy control valve for preventing the backflow of high-pressure gas according to claim 1, characterized in that: The connecting rod (12) is made of a hollow steel pipe or a plastic pipe.

8. The buoyancy control valve for preventing the backflow of high-pressure gas according to claim 1, characterized in that: The valve body (2) and the valve cover (5) are made of stainless steel and are formed by casting.

9. The buoyancy control valve for preventing the backflow of high-pressure gas according to claim 1, characterized in that: The valve sleeve (8) is made of carbon steel, and the cone valve core (9) and the spring (6) are made of manganese silicon steel.

10. The buoyancy control valve for preventing backflow of high pressure gas according to claim 1, characterized in that: The bolts (3) are high-strength bolts and are provided with anti-loosening washers.

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