A pressure protection cut-off valve

Abstract

The present invention relates to the field of valve technology, and proposes a pressure protection cut-off valve, comprising a valve body, a valve seat fixed to the top of the valve body, a hand plate rotatably arranged on the top of the valve seat, a main valve stem fixed to the bottom of the hand plate and threadedly connected to the valve seat, and a valve core arranged at the bottom of the main valve stem, wherein the bottom of the main valve stem is provided with a secondary valve stem capable of vertical telescopic sliding, the valve core is located at the end of the secondary valve stem, and the valve core is filled with a fluid for synchronously responding to the pressure change in the valve body; in the present invention, when the pressure in the valve cavity exceeds the set value, the elastic membrane contracts due to the pressure, and then the fluid in the liquid storage cavity acts on the air control component, which is then fed back to the actuator, and the secondary valve stem is driven by the actuator to slide downward relative to the main valve stem, thereby realizing pressure protection of the valve body. Compared with the prior art, the present invention adopts a layout form in which the flow and the medium in the valve body are separated, which solves the problem that the operation in the prior art is relatively complicated and there is a risk of medium leakage.

Description

Technical Field

[0001] The present invention relates to the technical field of valves, and in particular to a pressure protection cut-off valve. Background Art

[0002] The function of the cut-off valve is to quickly close the valve and cut off the pipeline to protect the safety of the system and equipment when an abnormal emergency occurs in the system pipeline. However, the cut-off valve currently used has the following problems: (i) Manual cut-off valves are time-consuming and laborious to operate, and may not be closed in time in some cases. (ii) Pneumatic cut-off valves require an external air source, the valve structure is complex, and the floor space is large.

[0003] After searching, the patent technology with announcement number CN107101026B discloses a safety shut-off valve and its control system, which includes: a hand wheel, a valve body, a bracket, a valve stem, a pressure cylinder, a cylinder, a solenoid valve, and an orifice flowmeter. The valve body is provided with a first channel and a second channel. The valve stem adopts a lifting type to drive the valve disc to move linearly along the center line of the fluid to achieve the cut-off of the medium and shorten the valve opening and closing stroke. When the pipeline flow is large, when the valve receives the flow exceeding the standard pulse output signal of the orifice flowmeter, the solenoid valve is actuated, the gas path is connected, and the valve is quickly closed; when the pipeline pressure rises sharply, the medium enters the pressure cylinder and the valve is automatically cut off to protect other equipment before and after. Therefore, it is widely used in natural gas pipelines with high safety performance and good effect.

[0004] However, the above-mentioned cut-off valve technology still has the following problems: the working mode of the above-mentioned cut-off valve is that when the pipeline pressure rises sharply and exceeds the limit value, the medium in the valve body enters the pressure cylinder, and the valve stem is driven by the pressure of the medium itself, and the valve stem drives the valve disc to move linearly, quickly cutting off the connection between the first channel and the second channel downward, thereby cutting off the medium to ensure the safety of the system. After the valve completes an opening and closing action, the valve needs to be manually reset so that the valve can work normally. The operation is relatively complicated and there is a risk of medium leakage, which affects the safe cutting effect of the valve. Summary of the invention

[0005] The present invention provides a pressure protection cut-off valve, which solves the problem in the prior art that the operation is relatively complicated and there is a risk of medium leakage.

[0006] The technical solution of the present invention is as follows: a pressure protection cut-off valve, comprising a valve body, a valve seat fixed to the top of the valve body, a hand plate rotatably arranged on the top of the valve seat, a main valve stem fixed to the bottom of the hand plate and threadedly connected to the valve seat, and a valve core arranged at the bottom of the main valve stem, the bottom of the main valve stem is provided with an auxiliary valve stem capable of vertical telescopic sliding, the valve core is located at the end of the auxiliary valve stem, the valve core is filled with a fluid for synchronously responding to pressure changes in the valve body, the auxiliary valve stem is provided with an air control component controlled by the fluid pressure in the valve core, the outer side of the main valve stem is provided with an actuator which drives the valve core to automatically cut off the flow in the valve body through the auxiliary valve stem under the control of the air control component, and the bottom of the auxiliary valve stem is provided with a regulating control component for regulating the initial pressure in the valve core.

[0007] Preferably, the valve body is provided with a lower valve port, an upper valve port, and a valve cavity located between the lower valve port and the upper valve port, and the valve core is placed in the valve cavity.

[0008] Preferably, the auxiliary valve stem includes a thick tube section, an upper thin tube section is provided on the top of the thick tube section, a lower thin tube section is provided on the bottom of the thick tube section, a spacer is fixed in the lower thin tube section, a first guide hole and a second guide hole are opened on the lower thin tube section, and the first guide hole and the second guide hole are respectively located above and below the spacer.

[0009] Preferably, the valve core includes an upper core body and a lower core body, both of which are fixed outside the auxiliary valve stem, an elastic membrane is fixed between the upper core body and the lower core body, and the elastic membrane and the upper and lower core bodies are enclosed to form a liquid storage cavity for accommodating fluid.

[0010] Preferably, the air control unit includes a pressure controller, a first piston, and a first spring elastically connecting the pressure controller to the first piston. The first piston is slidably disposed in the thick pipe section, and a fixed block fixed in the thick pipe section is disposed above the pressure controller.

[0011] Preferably, a pressure position is provided at the bottom of the pressure controller, and a pressure contact is provided at the top of the first piston vertically corresponding to the pressure position.

[0012] Preferably, the actuator comprises an upper fixing ring and a lower fixing ring, electromagnets are fixed on opposite sides of the upper fixing ring and the lower fixing ring, and the upper fixing ring and the lower fixing ring are elastically connected via a second spring.

[0013] Preferably, a guide groove is provided on the main valve stem, the upper fixed ring is slidably arranged outside the main valve stem, a guide block is fixed on the inner side of the upper fixed ring and is limited in the guide groove, the guide block is fixed outside the upper capillary section, and the lower fixed ring is fixed to the outer side of the bottom of the main valve stem.

[0014] Preferably, the adjustment control unit comprises a bolt, a swivel rotatably connected to the lower core body is fixed to the outer side of the bottom of the bolt, and a cross groove is formed on the bottom surface of the bolt.

[0015] Preferably, the adjustment control unit also includes a second piston, which is slidably arranged on the inner side of the bottom of the lower capillary section, and the bottom of the second piston is provided with a threaded hole threadedly connected to the bolt, the outer surface of the second piston is provided with a convex strip, and the inner wall of the lower capillary section is provided with a sliding groove slidably matched with the convex strip.

[0016] The beneficial effects of the present invention are:

[0017] In the present invention, when the pressure in the valve cavity exceeds the set value, the elastic membrane contracts under the pressure, and then the fluid in the liquid storage cavity acts on the air control unit, and then the air control unit feeds back to the actuator, and the actuator drives the auxiliary valve stem to slide downward relative to the main valve stem, that is, the valve core is driven downward and the lower core body at the bottom of the valve core conflicts with the lower valve port, so as to realize the pressure protection of the valve body and perform emergency shut-off of the valve. Compared with the prior art, the present invention adopts the layout form of separating the flow and the medium in the valve body, which solves the problem that the operation is relatively complicated and there is a risk of medium leakage in the prior art;

[0018] In the present invention, since the execution signal of the actuator comes from the air control unit, and the execution of the protection action of the air control unit is affected by the pressure of the fluid in the valve core, the regulation of the protection pressure setting value of the air control unit can be achieved by adjusting the initial pressure of the fluid in the valve core. Compared with the prior art, the present invention can be arbitrarily regulated according to needs through the adjustment control unit, and is convenient to use and operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0020] Figure 1 A partially cutaway three-dimensional structural schematic diagram of a pressure protection cut-off valve proposed by the present invention;

[0021] Figure 2 This is a schematic diagram of a half-cut three-dimensional structure of the main valve stem, the auxiliary valve stem and the valve core proposed by the present invention;

[0022] Figure 3 This is a schematic diagram of the half-section plan structure of the main valve stem, the auxiliary valve stem and the valve core proposed by the present invention;

[0023] Figure 4 This is a schematic diagram of a half-section three-dimensional structure of the main valve stem and the auxiliary valve stem proposed by the present invention;

[0024] Figure 5 This is a schematic diagram of a half-section three-dimensional structure of a valve core proposed by the present invention;

[0025] Figure 6This is a schematic diagram of the plane structure of the gas control unit proposed by the present invention;

[0026] Figure 7 This is a schematic diagram of the three-dimensional structure of the actuator proposed by the present invention;

[0027] Figure 8 This is a schematic diagram of the three-dimensional structure of the adjustment control unit proposed by the present invention;

[0028] In the figure: 1, valve body; 11, lower valve port; 12, upper valve port; 13, valve cavity; 2, valve seat; 3, hand plate; 4, main valve stem; 41, guide groove; 5, valve core; 51, upper core body; 52, lower core body; 53, elastic membrane; 6, auxiliary valve stem; 61, thick pipe section; 62, upper thin pipe section; 63, lower thin pipe section; 64, spacer; 65, first guide hole; 66, second guide hole; 7, air control unit; 71, pressure Force controller; 711, pressure position; 72, first piston; 721, pressure contact; 73, first spring; 74, fixed block; 8, actuator; 81, upper fixed ring; 82, lower fixed ring; 83, electromagnet; 84, second spring; 85, guide block; 9, adjustment control; 91, bolt; 911, swivel; 912, cross groove; 92, second piston; 921, threaded hole; 922, convex strip. DETAILED DESCRIPTION

[0029] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] See also Figure 1 , Figure 2 and Figure 3 The present invention provides a technical solution: a pressure protection cut-off valve, comprising a valve body 1, a valve seat 2 fixed on the top of the valve body 1, a hand plate 3 rotatably arranged on the top of the valve seat 2, a main valve stem 4 fixed on the bottom of the hand plate 3 and threadedly connected to the valve seat 2, and a valve core 5 arranged at the bottom of the main valve stem 4, a sub-valve stem 6 capable of vertical telescopic sliding is arranged at the bottom of the main valve stem 4, the valve core 5 is located at the end of the sub-valve stem 6, the valve core 5 is filled with a fluid for synchronously reacting to the pressure change in the valve body 1, the sub-valve stem 6 is provided with an air control unit 7 controlled by the fluid pressure in the valve core 5, the outer side of the main valve stem 4 is provided with an actuator 8 for automatically cutting off the flow in the valve body 1 through the sub-valve stem 6 under the control of the air control unit 7, and a regulating control unit 9 for regulating the initial pressure in the valve core 5 is arranged at the bottom of the sub-valve stem 6.

[0031] See also Figure 1 and Figure 5The valve body 1 is provided with a lower valve port 11, an upper valve port 12, and a valve cavity 13 between the lower valve port 11 and the upper valve port 12. The valve core 5 is placed in the valve cavity 13. The valve core 5 includes an upper core body 51 and a lower core body 52. ​​The upper core body 51 and the lower core body 52 are both fixed to the outside of the auxiliary valve stem 6. An elastic membrane 53 is fixed between the upper core body 51 and the lower core body 52. ​​The elastic membrane 53 and the upper core body 51 and the lower core body 52 enclose a liquid storage cavity for accommodating a fluid. The valve core 5 can move up and down in the valve cavity 13. The maximum upward movement of the valve core 5 is when the upper core body 51 conflicts with the upper valve port 12. At this time, the flow rate in the valve cavity 13 is the largest, and the maximum downward movement of the valve core 5 is when the lower core body 52 conflicts with the lower valve port 11. At this time, the flow rate in the valve cavity 13 is zero, and the elastic membrane 53 of the valve core 5 is directly in contact with the medium passing through the valve cavity 13. Since the fluid in the valve core 5 is filled in the liquid storage cavity formed by the elastic membrane 53, the upper core body 51 and the lower core body 52, it is affected by the pressure in the valve cavity 13.

[0032] See also Figure 3 , Figure 4 and Figure 6 The auxiliary valve stem 6 includes a thick tube section 61, an upper thin tube section 62 is provided at the top of the thick tube section 61, a lower thin tube section 63 is provided at the bottom of the thick tube section 61, a spacer 64 is fixed in the lower thin tube section 63, a first guide hole 65 and a second guide hole 66 are opened on the lower thin tube section 63, and the first guide hole 65 and the second guide hole 66 are respectively located above and below the spacer 64. The air control unit 7 includes a pressure controller 71, a first piston 72, and a first spring 73 that elastically connects the pressure controller 71 and the first piston 72. The first piston 72 is slidably arranged in the thick tube section 61, a fixing block 74 fixed in the thick tube section 61 is arranged above the pressure controller 71, and the bottom of the pressure controller 71 is provided with a fixing block 74 fixed in the thick tube section 61. A pressure position 711 is provided on the top of the first piston 72, and a pressure contact head 721 is provided vertically corresponding to the pressure position 711. When the pressure in the valve cavity 13 exceeds the set value, the elastic membrane 53 contracts under the pressure, and then the fluid in the liquid storage cavity is squeezed into the upper part of the inner cavity of the lower thin tube section 63 through the first guide hole 65 and enters the thick tube section 61. Due to the increase in the pressure in the thick tube section 61, the elastic force of the first spring 73 can be overcome to prompt the first piston 72 to move upward until the pressure contact head 721 on the top of the first piston 72 contacts the pressure position 711 of the pressure controller 71, and the pressure controller 71 can convert the pressure signal into an electrical signal and feed it back to the actuator 8.

[0033] See also Figure 3 and Figure 7The actuator 8 includes an upper fixing ring 81 and a lower fixing ring 82. Electromagnets 83 are fixed on opposite sides of the upper fixing ring 81 and the lower fixing ring 82. The upper fixing ring 81 and the lower fixing ring 82 are elastically connected by a second spring 84. A guide groove 41 is provided on the main valve stem 4. The upper fixing ring 81 is slidably arranged outside the main valve stem 4. A guide block 85 with a sliding limit in the guide groove 41 is fixed on the inner side of the upper fixing ring 81. The guide block 85 is fixed outside the upper thin tube section 62. The lower fixing ring 82 is fixed to the outer side of the bottom of the main valve stem 4. When the actuator 8 receives the protection signal instruction from the pressure controller 71, the two electromagnets 83 can work to generate magnetic attraction and drive the upper fixing ring 81 to overcome the elastic force of the second spring 84 and move downward. Under the sliding limit of the guide block 85 in the guide groove 41, the auxiliary valve stem 6 is driven to slide downward relative to the main valve stem 4, and the lower core body 52 at the bottom of the valve core 5 conflicts with the lower valve port 11, so as to realize the pressure protection cutoff of the valve body 1.

[0034] See also Figure 3 and Figure 8 The adjustment control unit 9 includes a bolt 91, a swivel 911 rotatably connected to the lower core body 52 is fixed to the outer side of the bottom of the bolt 91, a cross groove 912 is provided on the bottom surface of the bolt 91, and the adjustment control unit 9 also includes a second piston 92, which is slidably arranged on the inner side of the bottom of the lower capillary section 63, a threaded hole 921 threadedly connected to the bolt 91 is provided at the bottom of the second piston 92, a convex strip 922 is provided on the outer surface of the second piston 92, and a sliding groove slidably matched with the convex strip 922 is provided on the inner wall of the lower capillary section 63, the bolt 91 can be rotated by using a tool compatible with the bolt 91, and the second piston 92 can be driven to slide vertically in the lower capillary section 63 under the sliding limit of the convex strip 922 and the sliding groove on the inner wall of the lower capillary section 63.

[0035] The working principle and use process of the present invention are as follows: in the initial state, the valve core 5 can move up and down in the valve cavity 13, and the maximum limit of the upward movement of the valve core 5 is that the upper core body 51 conflicts with the upper valve port 12. At this time, the flow rate in the valve cavity 13 is the largest, and the maximum limit of the downward movement of the valve core 5 is that the lower core body 52 conflicts with the lower valve port 11. At this time, the flow rate in the valve cavity 13 is zero, and the elastic membrane 53 of the valve core 5 is directly in contact with the medium passing through the valve cavity 13. Since the fluid in the valve core 5 is filled in the liquid storage cavity formed by the elastic membrane 53, the upper core body 51, and the lower core body 52, and is affected by the pressure in the valve cavity 13, when the pressure in the valve cavity 13 exceeds the set value, the elastic membrane 53 is contracted by the pressure, and then the fluid in the liquid storage cavity passes through the first guide hole 65. The piston 72 is squeezed into the upper part of the inner cavity of the lower thin tube section 63 and enters the thick tube section 61. Due to the increase in the pressure in the thick tube section 61, the elastic force of the first spring 73 can be overcome to drive the first piston 72 upward until the pressure contact head 721 at the top of the first piston 72 contacts the pressure position 711 of the pressure controller 71. The pressure controller 71 can convert the pressure signal into an electrical signal and feed it back to the actuator 8, thereby making the two electromagnets 83 work to generate magnetic attraction and drive the upper fixing ring 81 to overcome the elastic force of the second spring 84 and move downward. Under the sliding limit of the guide block 85 in the guide groove 41, the auxiliary valve stem 6 is driven to slide downward relative to the main valve stem 4, and the lower core body 52 at the bottom of the valve core 5 contacts the lower valve port 11, so as to realize the pressure protection cutoff of the valve body 1.

[0036] Since the execution signal of the actuator 8 comes from the air control unit 7, and the execution of the protection action of the air control unit 7 is affected by the pressure of the fluid in the valve core 5, the regulation of the protection pressure setting value of the air control unit 7 can be achieved by adjusting the initial pressure of the fluid in the valve core 5. During the adjustment, the bolt 91 can be rotated by using a tool adapted to the bolt 91. The threaded relationship between the threaded hole 921 at the bottom of the second piston 92 and the bolt 91, and the sliding limit of the convex strip 922 and the inner wall groove of the lower capillary section 63 can drive the second piston 92 to slide vertically in the lower capillary section 63. When the second piston 92 moves downward, the fluid in the valve core 5 can be sucked into the inner cavity at the bottom of the lower capillary section 63 through the second guide hole 66, so that the initial pressure of the environment in the valve core 5 is reduced and the protection pressure setting value of the air control unit 7 is increased. Conversely, when the second piston 92 moves upward, the initial pressure of the environment in the valve core 5 is increased and the protection pressure setting value of the air control unit 7 is reduced.

[0037] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A pressure protection cut-off valve, comprising a valve body (1), a valve seat (2) fixed to the top of the valve body (1), a hand plate (3) rotatably arranged on the top of the valve seat (2), a main valve stem (4) fixed to the bottom of the hand plate (3) and threadedly connected to the valve seat (2), and a valve core (5) arranged at the bottom of the main valve stem (4), characterized in that: The bottom of the main valve stem (4) is provided with an auxiliary valve stem (6) capable of vertical telescopic sliding, the valve core (5) is located at the end of the auxiliary valve stem (6), the valve core (5) is filled with a fluid for synchronously responding to the pressure change in the valve body (1), the auxiliary valve stem (6) is provided with an air control unit (7) controlled by the fluid pressure in the valve core (5), the outer side of the main valve stem (4) is provided with an actuator (8) which, under the control of the air control unit (7), drives the valve core (5) to automatically cut off the flow in the valve body (1) through the auxiliary valve stem (6), and the bottom of the auxiliary valve stem (6) is provided with a regulating unit (9) for regulating the initial pressure in the valve core (5).

2. A pressure protection cut-off valve according to claim 1, characterized in that: The valve body (1) is provided with a lower valve port (11), an upper valve port (12), and a valve cavity (13) located between the lower valve port (11) and the upper valve port (12), and the valve core (5) is disposed in the valve cavity (13).

3. A pressure protection cut-off valve according to claim 1, characterized in that: The auxiliary valve stem (6) comprises a thick tube section (61), an upper thin tube section (62) is provided at the top of the thick tube section (61), a lower thin tube section (63) is provided at the bottom of the thick tube section (61), a spacer (64) is fixed inside the lower thin tube section (63), a first guide hole (65) and a second guide hole (66) are formed on the lower thin tube section (63), and the first guide hole (65) and the second guide hole (66) are respectively located above and below the spacer (64).

4. A pressure protection cut-off valve according to claim 3, characterized in that: The valve core (5) comprises an upper core body (51) and a lower core body (52), wherein the upper core body (51) and the lower core body (52) are both fixed outside the auxiliary valve stem (6), and an elastic membrane (53) is fixed between the upper core body (51) and the lower core body (52), and the elastic membrane (53) and the upper core body (51) and the lower core body (52) enclose a liquid storage cavity for accommodating a fluid.

5. A pressure protection cut-off valve according to claim 3, characterized in that: The air control unit (7) comprises a pressure controller (71), a first piston (72), and a first spring (73) elastically connecting the pressure controller (71) and the first piston (72); the first piston (72) is slidably disposed in the thick pipe section (61); and a fixing block (74) fixed in the thick pipe section (61) is disposed above the pressure controller (71).

6. A pressure protection cut-off valve according to claim 5, characterized in that: The bottom of the pressure controller (71) is provided with a pressure position (711), and the top of the first piston (72) is provided with a pressure contact (721) arranged vertically corresponding to the pressure position (711).

7. A pressure protection cut-off valve according to claim 3, characterized in that: The actuator (8) comprises an upper fixing ring (81) and a lower fixing ring (82), and electromagnets (83) are fixed to opposite sides of the upper fixing ring (81) and the lower fixing ring (82), and the upper fixing ring (81) and the lower fixing ring (82) are elastically connected via a second spring (84).

8. A pressure protection cut-off valve according to claim 7, characterized in that: The main valve stem (4) is provided with a guide groove (41), the upper fixing ring (81) is slidably arranged outside the main valve stem (4), a guide block (85) is fixed on the inner side of the upper fixing ring (81) and is slidably limited in the guide groove (41), the guide block (85) is fixed outside the upper capillary section (62), and the lower fixing ring (82) is fixed to the outer side of the bottom of the main valve stem (4).

9. A pressure protection cut-off valve according to claim 4, characterized in that: The adjustment control unit (9) comprises a bolt (91), a swivel (911) rotatably connected to the lower core body (52) being fixed to the outer side of the bottom of the bolt (91), and a cross groove (912) being provided on the bottom surface of the bolt (91).

10. A pressure protection cut-off valve according to claim 9, characterized in that: The adjustment control unit (9) further comprises a second piston (92), the second piston (92) being slidably disposed on the inner side of the bottom of the lower thin tube section (63), the bottom of the second piston (92) being provided with a threaded hole (921) threadedly connected to the bolt (91), the outer surface of the second piston (92) being provided with a convex strip (922), and the inner wall of the lower thin tube section (63) being provided with a sliding groove slidably matched with the convex strip (922).

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