A natural gas pipeline self-closing valve

Abstract

The present invention relates to the field of valve technology, and specifically to a natural gas pipeline self-closing valve, comprising a valve body, a pressure differential sensing mechanism and a valve assembly; a valve cavity is provided in the valve body, a first valve port is provided on the air inlet side of the valve cavity, and the valve assembly comprises a movable rod, a transmission rod and a blocking member; the movable rod moves when the pressure in the valve cavity changes, and then drives the blocking member to move and close the first valve port through the transmission rod; a second valve port is also provided in the valve body, and the second valve port is located on the air inlet side of the first valve port; the pressure differential sensing mechanism comprises a display member, a valve plate, a first elastic member, a sliding member and an adjustment assembly; the first elastic member is arranged between the sliding member and the valve plate, and prompts the valve plate to move away from the second valve port. By setting a display member to detect the working position of the valve plate in the valve body, the abnormal conditions of insufficient gas supply pressure and gas leakage can be distinguished, and the cause of the abnormality can be found more quickly and intuitively, saving time for abnormality troubleshooting. A position-adjustable sliding member is also provided to adapt to different gas supply pipelines and gas supply pressures.

Description

Technical Field

[0001] The present invention relates to the technical field of valves, and in particular to a natural gas pipeline self-closing valve. Background Art

[0002] Pipeline gas self-closing valves are installed on low-pressure gas system pipelines. When the pipeline experiences underpressure, overpressure, or leaks, they automatically close without requiring electricity or other external power, requiring manual opening. These self-operating valves offer long-term reliability. However, when the pipeline pressure is insufficient or leaks, the self-closing valve's spring force retracts, closing it. Operators must individually investigate the cause of the anomaly, which is time-consuming and labor-intensive, impacting maintenance efficiency. Summary of the Invention

[0003] The present invention provides a natural gas pipeline self-closing valve to solve the problem that the existing self-closing valve needs to check the causes one by one when it is abnormally closed, which affects the maintenance efficiency.

[0004] A natural gas pipeline self-closing valve of the present invention adopts the following technical solution:

[0005] A natural gas pipeline self-closing valve comprises a valve body, a pressure difference sensing mechanism and a valve assembly; a valve cavity is formed in the valve body, a first valve port is formed on the air inlet side of the valve cavity, and an air outlet side is connected to an external stove; the valve assembly comprises a movable rod, a transmission rod and a blocking member; the movable rod is slidably mounted on the valve body, and one end of the movable rod passes through the valve body; the blocking member is slidably mounted in the valve body, and is used to block and open the first valve port; one end of the movable rod located in the valve body is hinged to the blocking member through the transmission rod; the movable rod moves when the pressure in the valve cavity changes, and then drives the blocking member to move and close the first valve port through the transmission rod; a second valve port is also formed in the valve body. The second valve port is located on the air inlet side of the first valve port; the pressure difference sensing mechanism includes a display part, a valve plate, a first elastic part, a sliding part and an adjusting assembly; the valve plate is slidably installed in the valve body and is located on the air inlet side of the second valve port, and is used to block the second valve port; the sliding direction of the valve plate in the valve body is consistent with the flow direction of the gas in the valve body; the display part is installed in the valve body, and is used to display the working position of the valve plate in the valve body; the sliding part is installed in the valve body, and its position in the moving direction of the valve plate is adjustable; the first elastic part is arranged between the sliding part and the valve plate, and prompts the valve plate to move away from the second valve port; the adjusting assembly is used to adjust the position of the sliding part.

[0006] Furthermore, the adjustment assembly includes a first wedge block, a second wedge block and an adjustment knob; the first wedge block is fixed to the sliding member, and the second wedge block is fixed with a connecting rod that slides with the valve body, and the second wedge block is matched with the inclined surface of the first wedge block; the adjustment knob is installed on the valve body and is threadedly matched with the connecting rod.

[0007] Furthermore, the adjusting assembly is arranged between the sliding member and the valve chamber, and includes a fixed rod, an impeller and a second elastic member; the fixed rod is fixed in the valve body and extends along the sliding direction of the valve plate; the impeller is spirally engaged with the fixed rod, and rotates with the sliding member and moves synchronously along the extension direction of the fixed rod; the second elastic member is arranged between the impeller and the valve body, and is squeezed when the impeller drives the sliding member to move in a direction away from the first elastic member.

[0008] Furthermore, a synchronization ring is provided on the impeller, which is slidably mounted on the fixed rod and rotates and moves synchronously with the impeller; the second elastic member is a spring, which is sleeved outside the fixed rod and located between the impeller and the valve body.

[0009] Furthermore, the display component includes a connecting tube, an elastic twist and a third elastic component. A piston column is connected to the valve plate. The connecting tube is slidably installed on the valve body along a direction perpendicular to the sliding direction of the valve plate, and abuts against the elastic twist located outside the valve body; the third elastic component connects the elastic twist and the valve body, and causes the connecting tube to abut against the piston column through the elastic twist; when the valve plate moves to block the second valve port, the piston column allows the connecting tube to drive the elastic twist to move toward the direction close to the inside of the valve body.

[0010] Furthermore, the connecting pipe abuts against the circumferential surface of the piston column, and abuts against the end surface of the piston column when the valve plate blocks the second valve port, thereby preventing the valve plate from returning to its original position.

[0011] Furthermore, an elastic diaphragm is provided in the valve body, and the elastic diaphragm and the inner wall of the valve body constitute the valve cavity; the movable rod includes a first rod and a second rod, the first rod and the second rod are magnetically attracted, and the other end of the first rod passes through the outside of the valve body and is provided with a pull ring; the other end of the second rod is magnetically attracted to the inner wall of the valve body; the magnetic force between the first rod and the second rod is greater than the magnetic force between the second rod and the valve body; the first rod is connected to the elastic diaphragm, and the elastic diaphragm drives the first rod to move away from the second rod when the air pressure in the valve cavity increases; the second rod is hinged to the transmission rod.

[0012] Furthermore, a fixing frame is provided in the valve body, which is located on the air inlet side of the valve cavity and is fixed in the valve body; the fixing frame is a hollow structure and does not affect the circulation of gas, and the second valve port is opened on the fixing frame; the valve plate and the sliding member are slidably installed on the fixing frame along the same axis.

[0013] Furthermore, a flow equalizer is provided on the fixing frame, and the flow equalizer is provided on the air inlet side of the valve plate, for evenly dispersing the airflow and then flowing to the second valve port through the edge of the valve plate.

[0014] Furthermore, the first elastic member and the third elastic member are both springs.

[0015] The beneficial effect of the present invention is that the natural gas pipeline self-closing valve of the present invention distinguishes between insufficient gas supply pressure and gas leakage by providing an indicator to detect the working position of the valve plate within the valve body. When the first valve port is blocked, if the indicator shows that the valve plate has blocked the second valve port, it indicates that there is a gas leak on the gas outlet side of the valve body; if the indicator shows that the valve plate has not blocked the second valve port, it indicates that the gas supply pressure within the valve body is insufficient. This arrangement allows the cause of the abnormality to be identified more quickly and intuitively, saving time in abnormality troubleshooting.

[0016] Furthermore, by providing an adjustable sliding member, the distance that the first elastic member pushes the valve plate away from the second valve port can be changed, thereby adjusting the valve plate's sensitivity in closing the second valve port and adapting to different air supply lines and pressures. Furthermore, if the first elastic member ages due to prolonged use, the sliding member's position can be adjusted to further push the valve plate away from the second valve port, compensating for the effect of aging on the valve plate's sensitivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 This is a schematic diagram of the overall structure of an embodiment of a natural gas pipeline self-closing valve of the present invention;

[0019] Figure 2 A side view of an embodiment of a natural gas pipeline self-closing valve of the present invention;

[0020] Figure 3 for Figure 2 Schematic diagram of the cross section along the AA direction;

[0021] Figure 4 for Figure 3 A magnified schematic diagram of point B in the middle;

[0022] Figure 5 This is a schematic diagram of the overall structure of another embodiment of a natural gas pipeline self-closing valve of the present invention;

[0023] Figure 6 It is a cross-sectional schematic diagram of another embodiment of a natural gas pipeline self-closing valve of the present invention;

[0024] Figure 7 for Figure 6 Enlarged schematic diagram of point C in the middle;

[0025] In the figure: 100, valve body; 110, valve chamber; 120, first valve port; 130, second valve port; 140, elastic diaphragm; 150, fixing frame; 151, flow equalizer; 200, pressure difference sensing mechanism; 210, display member; 211, connecting pipe; 212, torsion spring; 213, third elastic member; 220, valve plate; 221, piston column; 230, first elastic member; 240, sliding member; 251, first wedge block; 252, second wedge block; 253, adjusting knob; 254, connecting rod; 261, fixing rod; 262, impeller; 263, second elastic member; 264, synchronizing ring; 300, valve assembly; 310, movable rod; 311, first rod member; 312, second rod member; 313, pull ring; 320, transmission rod; 330, blocking member. DETAILED DESCRIPTION

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0027] An embodiment of a natural gas pipeline self-closing valve of the present invention is as follows Figures 1 to 4 As shown, it includes a valve body 100 , a pressure difference sensing mechanism 200 and a valve assembly 300 .

[0028] A valve cavity 110 is defined within the valve body 100. A first valve port 120 is defined on the air inlet side of the valve cavity 110, and the air outlet side is connected to an external stove. Specifically, an elastic diaphragm 140 is provided within the valve body 100, and the elastic diaphragm 140 and the inner wall of the valve body 100 form the valve cavity 110. The valve assembly 300 includes a movable rod 310, a transmission rod 320, and a blocking member 330. The movable rod 310 is slidably mounted on the valve body 100, with one end extending out of the valve body 100. The blocking member 330 is slidably mounted within the valve body 100 and is used to block and open the first valve port 120. One end of the movable rod 310 located within the valve body 100 is hingedly connected to the blocking member 330 via the transmission rod 320. The movable rod 310 moves when the pressure in the valve cavity 110 changes, thereby driving the blocking member 330 to move and close the first valve port 120 via the transmission rod 320. Specifically, the movable rod 310 includes a first rod member 311 and a second rod member 312. The first rod member 311 and the second rod member 312 are magnetically attracted, and the other end of the first rod member 311 passes through the outside of the valve body 100 and is provided with a pull ring 313; the other end of the second rod member 312 is magnetically attracted to the inner wall of the valve body 100; the magnetic force between the first rod member 311 and the second rod member 312 is greater than the magnetic force between the second rod member 312 and the valve body 100; the first rod member 311 is connected to the elastic diaphragm 140, and the elastic diaphragm 140 drives the first rod member 311 to move away from the second rod member 312 when the air pressure in the valve chamber 110 increases; the second rod member 312 is hinged to the transmission rod 320.

[0029] The valve body 100 also defines a second valve port 130, located on the air inlet side of the first valve port 120. The pressure differential sensing mechanism 200 includes an indicator 210, a valve plate 220, a first elastic member 230, a sliding member 240, and an adjustment assembly. The valve plate 220 is slidably mounted within the valve body 100 and is located on the air inlet side of the second valve port 130, sealing the second valve port 130. The sliding direction of the valve plate 220 within the valve body 100 aligns with the direction of gas flow within the valve body 100. The indicator 210 is mounted within the valve body 100 to indicate the operating position of the valve plate 220 within the valve body 100. The sliding member 240 is mounted within the valve body 100 and is adjustable in the direction of movement of the valve plate 220. The first elastic member 230 is a spring, positioned between the sliding member 240 and the valve plate 220, and urges the valve plate 220 away from the second valve port 130. The adjustment assembly is used to adjust the position of the sliding member 240 .

[0030] The valve assembly 300 is a self-closing valve structure known in the prior art. When operating in conjunction with the valve plate 220, it can extend and retract the first rod 311 based on changes in air pressure within the valve chamber 110. Specifically, when the air supply pressure within the valve body 100 exceeds normal, the elastic diaphragm 140 expands, driving the first rod 311 to extend and disengage from the second rod 312. The second rod 312 then magnetically attracts the valve body 100, driving the blocking member 330 via the transmission rod 320 to seal the first valve port 120, thereby blocking the flow of gas. At this point, the first rod 311 is in an extended state. When the air supply pressure within the valve body 100 falls below normal, the tension of the elastic diaphragm 140 is insufficient to allow the first rod 311 to overcome the magnetic force between the second rod 312 and the valve body 100. Consequently, the second rod 312 engages the valve body 100, driving the blocking member 330 via the transmission rod 320 to seal the first valve port 120. At this point, the first rod 311 is in a retracted state. When gas flows normally through the valve body 100 and its outlet side operates normally, the first rod 311 and the second rod 312 engage, and the second rod 312 disengages from the valve body 100, with the first rod 311 in a position intermediate between the extended and retracted states. When gas leaks from the outlet side of the valve body 100, an overcurrent occurs within the valve body 100, causing a change in the pressure differential across the valve plate 220, prompting the valve plate 220 to move and seal the second valve port 130, thereby reducing the pressure within the valve cavity 110. The tension of the elastic diaphragm 140 is insufficient to allow the first rod 311 to overcome the magnetic force between the second rod 312 and the valve body 100, causing the second rod 312 to engage with the valve body 100 and, via the transmission rod 320, drive the sealing member 330 to seal the first valve port 120. At this point, the first rod 311 is in a retracted state, and the indicator 210 can display the changes in the valve plate 220.

[0031] When the valve body 100's internal air supply pressure is insufficient or an air leak occurs, the movable rod 310 will retract inward, causing the blocking member 330 to block the first valve port 120. When an abnormality occurs, the operator needs to identify the cause of the abnormality one by one. By providing an indicator 210 to detect the working position of the valve plate 220 within the valve body 100, it is possible to distinguish between abnormal conditions of insufficient air supply pressure and abnormal conditions of air leakage. When the first valve port 120 is blocked, if the indicator 210 shows that the valve plate 220 has blocked the second valve port 130, it indicates that an air leak has occurred on the air outlet side of the valve body 100. If the indicator 210 shows that the valve plate 220 has not blocked the second valve port 130, it indicates that the air supply pressure within the valve body 100 is insufficient. This configuration allows the cause of the abnormality to be identified more quickly and intuitively, saving time in troubleshooting.

[0032] Furthermore, by providing an adjustable position slider 240, the distance that the first elastic member 230 pushes the valve plate 220 away from the second valve port 130 can be changed, thereby adjusting the sensitivity of the valve plate 220 in closing the second valve port 130, thereby adapting to different air supply lines and air supply pressures. Furthermore, if the first elastic member 230 ages due to long-term use, the position of the slider 240 can be adjusted to further push the first elastic member 230 away from the second valve port 130, thereby compensating for the impact of the aging of the first elastic member 230 on the sensitivity of the valve plate 220.

[0033] In this embodiment, the adjustment assembly includes a first wedge 251, a second wedge 252, and an adjustment knob 253. The first wedge 251 is fixed to the sliding member 240, and a connecting rod 254 is fixed to the second wedge 252, which slides with the valve body 100. The second wedge 252 and the first wedge 251 have an inclined surface that engages. The adjustment knob 253 is mounted on the valve body 100 and threadedly engages with the connecting rod 254. The connecting rod 254 is perpendicular to the sliding direction of the valve plate 220. By rotating the adjustment knob 253, the connecting rod 254 moves along its axial direction, thereby causing the second wedge 252 to slide relative to the first wedge 251, thereby changing the position of the sliding member 240 within the valve body 100. Among them, in order to prevent the sliding member 240 from moving in the valve body 100, the inclined surfaces of the second wedge block 252 and the first wedge block 251 cooperate with each other through key grooves extending along the inclination direction of their respective inclined surfaces, so that the second wedge block 252 and the first wedge block 251 will never separate while sliding relative to each other, and the position of the sliding member 240 is fixed after the position of the sliding member 240 is adjusted.

[0034] In this embodiment, the indicator member 210 includes a connecting tube 211, a spring 212, and a third elastic member 213. A piston column 221 is connected to the valve plate 220. The connecting tube 211 is slidably mounted on the valve body 100 in a direction perpendicular to the sliding direction of the valve plate 220 and abuts against the spring 212 located outside the valve body 100. The third elastic member 213 is a spring and connects the spring 212 to the valve body 100. The spring 212 forces the connecting tube 211 to abut against the piston column 221. When the valve plate 220 moves to block the second valve port 130, the piston column 221 allows the connecting tube 211 to drive the spring 212 toward the interior of the valve body 100. Specifically, the connecting tube 211 abuts against the circumferential surface of the piston column 221. When the valve plate 220 blocks the second valve port 130, the connecting tube 211 abuts against the end surface of the piston column 221, thereby preventing the valve plate 220 from returning to its original position. After the abnormality is resolved, the elastic member 212 is pulled outward, so that the valve plate 220 moves to open the second valve port 130 under the action of the first elastic member 230 .

[0035] In this embodiment, a fixing bracket 150 is provided in the valve body 100. The fixing bracket 150 is located on the air inlet side of the valve cavity 110 and is fixed in the valve body 100. The fixing bracket 150 is a hollow structure and does not affect the circulation of the gas. The second valve port 130 is opened on the fixing bracket 150. The valve plate 220 and the sliding member 240 are slidably installed on the fixing bracket 150 along the same axis.

[0036] In this embodiment, a flow equalizer 151 is provided on the fixing frame 150 . The flow equalizer 151 is provided on the air inlet side of the valve plate 220 to evenly disperse the airflow and then flow through the edge of the valve plate 220 to the second valve port 130 .

[0037] In some other embodiments, such as Figures 5 to 7 As shown, unlike the above embodiment, the adjustment assembly is disposed between the sliding member 240 and the valve chamber 110 and includes a fixed rod 261, an impeller 262, and a second elastic member 263. The fixed rod 261 is fixed within the valve body 100 and extends along the sliding direction of the valve plate 220. The impeller 262 is screwed together with the fixed rod 261 and rotates with the sliding member 240 and moves synchronously along the extension direction of the fixed rod 261. The second elastic member 263 is disposed between the impeller 262 and the valve body 100 and is compressed when the impeller 262 drives the sliding member 240 to move away from the first elastic member 230. A synchronizer ring 264 is provided on the impeller 262, which is slidably mounted on the fixed rod 261 and rotates and moves synchronously with the impeller 262. The second elastic member 263 is a spring and is sleeved outside the fixed rod 261 and located between the impeller 262 and the valve body 100. Specifically, the synchronizing ring 264 and the sliding member 240 are respectively rotatably engaged with the impeller 262 via annular grooves formed on both sides of the impeller 262. The annular grooves are T-shaped grooves, allowing the synchronizing ring 264, the sliding member 240, and the impeller 262 to move synchronously. The synchronizing ring 264 is provided to prevent the second elastic member 263 from twisting during the rotation of the impeller 262. When the gas flows in the valve body 100, it drives the impeller 262 to rotate, so that the impeller 262 overcomes the elastic force of the second elastic member 263 and moves to the side away from the sliding member 240 under the spiral cooperation with the fixing rod 261, thereby making it easier for the valve plate 220 to overcome the elastic force of the first elastic member 230 and thus the second valve port 130; the faster the gas flows in the valve body 100, the easier it is for the impeller 262 to move in the direction away from the sliding member 240, and the easier it is for the valve plate 220 to close the second valve port 130. When a gas leakage occurs and causes gas to flow excessively, the impeller 262 can enable the valve plate 220 to respond more quickly to close the second valve port 130, further reducing gas leakage.

[0038] The above description is only a preferred embodiment of the present invention and is 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 scope of protection of the present invention.

Claims

1. A natural gas pipeline self-closing valve, characterized by: Includes a valve body, a pressure differential sensing mechanism, and a valve assembly; A valve cavity is defined within the valve body, a first valve port is defined on the air inlet side of the valve cavity, and the air outlet side is connected to an external stove; the valve assembly includes a movable rod, a transmission rod, and a blocking member; the movable rod is slidably mounted within the valve body, with one end extending out of the valve body; the blocking member is slidably mounted within the valve body for blocking and opening the first valve port; one end of the movable rod within the valve body is hingedly connected to the blocking member via the transmission rod; the movable rod moves when the pressure in the valve cavity changes, thereby driving the blocking member to move and close the first valve port via the transmission rod; A second valve port is further defined within the valve body and is located on the air inlet side of the first valve port. The differential pressure sensing mechanism comprises a display element, a valve plate, a first elastic element, a sliding element, and an adjusting assembly. The valve plate is slidably mounted within the valve body and is located on the air inlet side of the second valve port, for sealing the second valve port. The sliding direction of the valve plate within the valve body is consistent with the flow direction of the gas within the valve body. The display element is mounted within the valve body and is configured to display the working position of the valve plate within the valve body. The sliding element is mounted within the valve body and is positionally adjustable in the direction of movement of the valve plate. The first elastic element is disposed between the sliding element and the valve plate and urges the valve plate away from the second valve port. The adjusting assembly is configured to adjust the position of the sliding element. The display component includes a connecting tube, an elastic twist and a third elastic component. A piston column is connected to the valve plate. The connecting tube is slidably installed on the valve body along a direction perpendicular to the sliding direction of the valve plate, and abuts against the elastic twist located outside the valve body; the third elastic component connects the elastic twist and the valve body, and causes the connecting tube to abut against the piston column through the elastic twist; when the valve plate moves to block the second valve port, the piston column allows the connecting tube to drive the elastic twist to move toward the direction close to the inside of the valve body.

2. A natural gas pipeline self-closing valve according to claim 1, characterized in that: The adjustment assembly includes a first wedge block, a second wedge block and an adjustment knob; the first wedge block is fixed to the sliding member, and the second wedge block is fixed with a connecting rod that slides with the valve body, and the second wedge block is matched with the inclined surface of the first wedge block; the adjustment knob is installed on the valve body and is threaded with the connecting rod.

3. A natural gas pipeline self-closing valve according to claim 1, characterized in that: The adjusting assembly is arranged between the sliding member and the valve cavity, and includes a fixed rod, an impeller and a second elastic member; the fixed rod is fixed in the valve body and extends along the sliding direction of the valve plate; the impeller is spirally engaged with the fixed rod, and rotates with the sliding member and moves synchronously along the extension direction of the fixed rod; the second elastic member is arranged between the impeller and the valve body, and is squeezed when the impeller drives the sliding member to move in a direction away from the first elastic member.

4. A natural gas pipeline self-closing valve according to claim 3, characterized in that: The impeller is provided with a synchronization ring, which is slidably mounted on the fixed rod and rotates and moves synchronously with the impeller; the second elastic member is a spring, which is sleeved outside the fixed rod and located between the impeller and the valve body.

5. The natural gas pipeline self-closing valve according to claim 1, characterized in that: The connecting pipe abuts against the circumferential surface of the piston column, and abuts against the end surface of the piston column when the valve plate blocks the second valve port to prevent the valve plate from returning to its original position.

6. A natural gas pipeline self-closing valve according to claim 1, characterized in that: An elastic diaphragm is provided in the valve body, and the elastic diaphragm and the inner wall of the valve body form the valve cavity; the movable rod includes a first rod member and a second rod member, the first rod member and the second rod member are magnetically attracted, and the other end of the first rod member passes through the outside of the valve body and is provided with a pull ring; the other end of the second rod member is magnetically attracted to the inner wall of the valve body; The magnetic force between the first rod and the second rod is greater than the magnetic force between the second rod and the valve body; the first rod is connected to the elastic diaphragm, and the elastic diaphragm drives the first rod to move away from the second rod when the air pressure in the valve cavity increases; the second rod is hinged to the transmission rod.

7. The natural gas pipeline self-closing valve according to claim 1, characterized in that: A fixing frame is provided in the valve body, which is located on the air inlet side of the valve cavity and is fixed in the valve body; the fixing frame is a hollow structure and does not affect the circulation of gas, and the second valve port is opened on the fixing frame; the valve plate and the sliding member are slidably installed on the fixing frame along the same axis.

8. A natural gas pipeline self-closing valve according to claim 7, characterized in that: A flow equalizer is provided on the fixing frame and is arranged on the air inlet side of the valve plate to evenly disperse the airflow and then flow to the second valve port through the edge of the valve plate.

9. The natural gas pipeline self-closing valve according to claim 1, characterized in that: The first elastic member and the third elastic member are both springs.

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