Double-operation type surface safety valve

Abstract

A double-operation type surface safety valve belongs to a surface safety valve used in the field of oil and gas exploitation and comprises a valve body provided with a valve cavity, and an actuating hole is formed in one side of the valve cavity of the valve body; the valve plate is matched with the valve cavity so as to be used for opening and closing the double-operation type ground safety valve; the valve rod is inserted into the valve cavity from the actuating hole and is fixedly connected with the valve plate; the pneumatic actuating mechanism is assembled on the side, where the actuating hole is located, of the valve body so as to control the valve plate to displace; and the auxiliary executing mechanism is assembled at one end, far away from the valve body, of the pneumatic executing mechanism, and an actuating part of the auxiliary executing mechanism is combined or jointed with the valve rod through an actuating piece of the pneumatic executing mechanism. The valve is provided with the pneumatic executing mechanism serving as a main executing mechanism and the auxiliary executing mechanism serving as an auxiliary executing mechanism, and when the pneumatic executing mechanism breaks down or fails, the auxiliary executing mechanism is started to ensure that the ground safety valve is still in a controllable state, so that the reliability of the ground safety valve is improved on the whole.

Description

TECHNICAL FIELD

[0001] The utility model relates to a ground safety valve. BACKGROUND

[0002] In the oil and gas exploitation process, in order to ensure the safety of wellhead, protect wellhead equipment, production pipeline and oil and gas resources, the Christmas tree will be configured with ground safety valve. The control type of ground safety valve is generally hydraulic, pneumatic or electric. When ground safety valve works, the pressure is applied through the interface to drive the piston down, and the valve is opened. When emergency occurs or well shut down or flow is needed, the pressure is released, and the built-in spring is reset, and the valve is closed, effectively protecting the safety of wellhead and ground equipment.

[0003] However, the existing pneumatic safety valve is driven by gas source pressure to drive the piston down, and the valve is opened. Once the gas supply device fails, the pneumatic safety valve will reset and close the ground safety valve, affecting the on-site production.

[0004] In addition, involving the failure of gas supply device, one situation is that the pneumatic safety valve itself fails. The main reason for this failure is that the pneumatic safety valve air bag is usually compressed by peripheral bolts to achieve sealing. In a long time of use, the bolts are prone to looseness, which causes gas leakage and use failure, seriously affecting the on-site production efficiency. UTILITY MODEL CONTENT

[0005] Therefore, the purpose of the utility model is to provide a double-operated ground safety valve to improve the reliability of the ground safety valve.

[0006] According to the embodiment of the utility model, a double-operated ground safety valve is provided, which comprises:

[0007] A valve body has a valve cavity, and the valve body is provided with an actuating hole on one side of the valve cavity;

[0008] A valve plate cooperates with the valve cavity to open and close the double-operated ground safety valve;

[0009] A valve rod is connected between the actuating hole and the valve plate;

[0010] A pneumatic actuator is arranged on the side of the actuating hole of the valve body to control the displacement of the valve plate; and

[0011] A secondary actuator is arranged at one end of the pneumatic actuator away from the valve body, and the actuating part of the secondary actuator is combined or engaged with the valve rod through the actuating part of the pneumatic actuator.

[0012] Optionally, the pneumatic actuator is a diaphragm type pneumatic actuator, which comprises:

[0013] lower cylinder body, having a lower intervention hole for the intervention of a valve stem;

[0014] upper cylinder body, having an upper intervention hole for the intervention of the actuating part; and

[0015] diaphragm, clamped between the upper cylinder body and the lower cylinder body, forming an upper diaphragm chamber with the upper cylinder body and a lower diaphragm chamber with the lower cylinder body, wherein the upper diaphragm chamber is connected to a compressed air source; the diaphragm is connected to the actuating part and the valve stem simultaneously.

[0016] Optionally, the end of the lower cylinder body and the upper cylinder body, which are opposite to each other, has a lower flange;

[0017] Optionally, the end of the lower cylinder body and the upper cylinder body, which are opposite to each other, has a lower flange;

[0018] A combined ring is provided, which has a clamping ring groove on the inner side of the ring;

[0019] Correspondingly, the upper flange and the lower flange form a convex ring after clamping the outer edge of the diaphragm, and the clamping ring groove of the combined ring cooperates with the convex ring to further narrow the opening and lock the upper cylinder body and the lower cylinder body which are opposite to each other.

[0020] Optionally, the combined ring comprises two fixed rings with a central angle greater than or equal to 175° and less than or equal to 180°, which are referred to as left fixed ring and right fixed ring;

[0021] Each end of the fixed ring has an outwardly extending ear, and the ear has a fixing hole;

[0022] Correspondingly, the fixing holes of the corresponding ears of the left fixed ring and the right fixed ring are aligned and connected by using bolts or screws.

[0023] Optionally, a sealing ring is arranged in the clamping ring groove.

[0024] Optionally, the upper flange constitutes an upper flange, and the lower flange constitutes a lower flange;

[0025] Correspondingly, the upper cylinder body and the lower cylinder body are connected by flanges to be assembled into a cylinder body.

[0026] Optionally, a indicating rod is provided for the connection of the actuating part and the valve stem;

[0027] A connecting seat is provided, which is fitted in the upper intervention hole and provides a guide hole;

[0028] The indicating rod is guided in the guide hole, and a sealing assembly is arranged in the guide hole;

[0029] A detection element is further provided to detect the state of the indicating rod, so as to determine the starting time of the secondary actuating mechanism.

[0030] Optionally, the auxiliary actuator is an electric push rod, a linear motor, or a rotary motor;

[0031] If it is a rotary motor, a lead screw mechanism is provided to convert the rotary motion of the rotary motor into linear motion.

[0032] Optionally, the lower access port is fitted with a downwardly extending cylinder, the end of which is fitted with a spring-loaded lower support.

[0033] Accordingly, the lower surface of the diaphragm is fitted with a spring-loaded upper support.

[0034] A spring is provided between the upper support and the lower support of the spring for the reset of the diaphragm.

[0035] Optionally, a valve cover is provided at the lower end of the cylinder; the valve cover includes a cover body and an upwardly extending sealing cylinder;

[0036] The lower surface of the valve cover has a tapered stop, which is used to seal with the actuation hole.

[0037] The sealing cylinder is equipped with a packing seal assembly for dynamic sealing of the valve stem.

[0038] The dual-operation ground safety valve according to the present utility model embodiment has both a pneumatic actuator and a secondary actuator. The pneumatic actuator is the main actuator, and the secondary actuator is an auxiliary actuator, similar to a standby actuator. When the pneumatic actuator malfunctions or fails, the secondary actuator is activated to ensure that the ground safety valve remains under control, thereby improving the overall reliability of the ground safety valve. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the main cross-section of a dual-operation ground safety valve in one embodiment.

[0040] Figure 2 This is a schematic diagram of the main cross-sectional structure of the valve body in one embodiment.

[0041] Figure 3 This is a schematic diagram of the main cross-sectional structure of a pneumatic actuator in one embodiment.

[0042] Figure 4 This is a schematic diagram of the main cross-sectional structure of the electric motor actuator in one embodiment.

[0043] Figure 5 This is a top view of the fixed ring structure in one embodiment.

[0044] Figure 6 for Figure 5 AA sectional view.

[0045] In the diagram: A. Valve body, B. Pneumatic component and valve plate assembly, C. Electric operating component.

[0046] 1. Pipe fitting, 2. Grease plug, 3. Flow channel, 4. Valve chamber, 5. Valve cover seat, 6. Valve plate, 7. Valve seat, 8. Valve passage, 9. Through hole, 10. Connecting fish mouth, 11. Sealing ring, 12. Valve cover, 13. Hex head nut, 14. Bolt, 15. Spring, 16. Lower cylinder body, 17. Lower diaphragm chamber, 18. Lower flange, 19. Upper flange, 20. Plug, 21. Air inlet, 22. Upper cylinder body, 23. Upper diaphragm chamber, 24. Connecting seat, 25. Sealing assembly, 26. Indicator rod, 27. Threaded head, 28. Connecting seat, 29. Pressure relief valve, 30. Diaphragm, 31. Retaining ring, 32. Spring upper support seat, 33. Cylinder barrel, 34. Adjusting assembly; 35. Packing gland; 36. Valve stem; 37. Lower spring support; 38. Packing seal; 39. Tapered stop; 40. Sheath; 41. Bushing; 42. Bearing; 43. Lead screw; 44. Slide plate; 45. Slider; 46. Guide rail; 47. Bearing; 48. Coupling; 49. Electric flange retaining sleeve; 50. Key; 51. Reducer; 52. Motor; 53. Cable; 54. Pin; 55. Round nut; 56. Connecting screw; 57. Hex socket head cap screw; 58. Internal thread; 59. Nut; 60. Left retaining ring; 61. Right retaining ring; 62. Bolt; 63. Sealing ring; 64. Slot. Detailed Implementation

[0047] Based on the concept of this utility model, in a preferred embodiment, the main body of the dual-operation ground safety valve is a pneumatic diaphragm valve section, which is referred to as the pneumatic diaphragm valve for simplicity. Therefore, unless otherwise specified, the structure and construction of the dual-operation ground safety valve can be referenced from the known structures and / or constructions of pneumatic diaphragm valves.

[0048] Given that, in the installed state, the pneumatic actuator of the pneumatic diaphragm valve is usually located on the upper side of the valve body A, it often has a defined upper and lower structure.

[0049] Furthermore, since ground safety valves are usually installed on ground pipelines, their valve body A often has a pipe structure section, with a pipe connector 1 at each end of the pipe structure section for connecting to the controlled pipeline. Therefore, the valve body A of the ground safety valve often has relatively obvious pipe characteristics and has a clear pipe structure reference system.

[0050] In an embodiment of this utility model, an auxiliary actuator, referred to below as the sub-actuator, is further introduced based on the pneumatic ground safety valve.

[0051] See Figure 1The dual-operated ground safety valve based on this utility model mainly comprises three parts, which, from bottom to top in the figure, are valve body A, pneumatic part and valve plate assembly B, and electric operating part C. The main body of valve body A is a tubular structure with a cavity. The cavity is positioned in the middle relative to the valve structure. Figure 2 The flow channel 3 shown has a valve cavity 4 with a large cross-sectional area.

[0052] The valve body A has an actuation hole on one side of the pipe section where the valve cavity 4 is located, for the intervention of the actuator to drive the valve plate 6. The side with the actuation hole is usually the upper side of the valve body A, and correspondingly, a valve cover seat 5 is formed at the actuation hole. This is common knowledge in the field and will not be elaborated here.

[0053] Valve plate 6 is the functional component used for opening and closing the ground safety valve. Valve plate 6 has a through hole 9. When the ground safety valve is closed, the through hole 9 of valve plate 6 is misaligned with the flow channel 3 of valve body A, thus keeping the ground safety valve closed. That is, the ground safety valve is normally closed, and valve plate 6 is in the upper stop position. In the working state, the pneumatic actuator moves, causing valve plate 6 to move downwards, and the through hole 9 of valve plate 6... Figure 2 The flow channels 3 shown are roughly in a state of overlapping axes, which allows the ground safety valve to be fully opened. At this time, the valve plate 6 is in the lower stop position, i.e. Figure 3 The state shown in the image.

[0054] If the pneumatic actuator loses pressure, valve plate 6 will rise under the action of the reset force, and valve plate 6 will reach the closed position, affecting the normal operation of the wellhead and surface equipment. Therefore, relying solely on the reliability of the pneumatic actuator itself will reduce the reliability of the surface safety valve itself.

[0055] It should be known that pneumatic equipment or components are inherently prone to leakage, and the corresponding seals are vulnerable parts. Therefore, the reliability of pneumatic actuators is relatively poor, and their current availability is often not detected in time, which affects the normal operation of oil and gas extraction.

[0056] Regarding the displacement control of valve plate 6, a pneumatic actuator is first provided for the displacement control of valve plate 6. The operation of valve plate 6 is achieved by means of valve stem 36, which enters the valve cavity 4 through the actuation hole and is fixedly connected to valve plate 6.

[0057] Furthermore, the pneumatic actuator is typically mounted on the valve cover 12 of the ground safety valve. Figure 2 and Figure 3 The illustrated structure is primarily used to conveniently display the relationships between various components, without explicitly distinguishing the inclusion relationships between components. For example... Figure 3 The valve cover 12 shown should be included in the valve body A. It is indicated in [the diagram] to highlight the relationship between the valve cover 12 and the pneumatic actuator.Figure 3 However, this does not mean that valve cover 12 is a component of a pneumatic actuator.

[0058] The actuator of the pneumatic actuator is connected to the valve stem 36, and the valve stem 36 is displaced by the action of the pneumatic actuator.

[0059] To improve the overall reliability of the ground safety valve, an auxiliary actuator is provided, which is mounted on the end of the pneumatic actuator away from the valve body. The actuating part of the auxiliary actuator is connected or engaged with the valve stem 36 via the actuating element of the pneumatic actuator.

[0060] It should be understood that coupling is a form of connection, while engagement is a non-connection method that relies on contact to achieve support or transmission, which will not be elaborated further. However, in a more preferred embodiment, engagement is preferred to reduce excessive interference of the auxiliary actuator on the pneumatic actuator.

[0061] exist Figure 3 In the illustrated structure, the indicator rod 26 shown in the figure is fixed to the diaphragm 30 and passes through the upper intervention hole provided on the upper cylinder 22.

[0062] exist Figure 4 In the illustrated structure, the lower end of the lead screw 43 is a bushing 41. In some embodiments, the bushing 41 abuts against, rather than engages with, the upper end of the indicator rod 26; this is referred to as the top dead center state of the indicator rod 26. Under this condition, if the auxiliary actuator does not operate, the indicator rod 26 will move with the movement of the diaphragm 30. Under this condition, when the indicator rod 26 is not in the top dead center state, the indicator rod 26 is disengaged from the bushing 41, meaning that the downward movement of the diaphragm 30 is not affected by the auxiliary actuator.

[0063] In some embodiments, the bushing 41 may be coupled to the indicator rod 26, and in the direction of the indicator rod 26, the bushing 41 moves with the indicator rod 26 when the auxiliary actuator is not activated. In this case, the bushing 41 needs to be given a certain position relative to the auxiliary actuator. Figure 4 The degrees of freedom in the up and down directions shown or the resistance force generated by the auxiliary actuator are relatively small, thus having a small impact on the movement of the indicator rod 26 to the diaphragm 30.

[0064] To more clearly describe the connection between the auxiliary actuator and the pneumatic actuator, the pneumatic actuator will be explained in detail below:

[0065] Regarding the pneumatic actuator, a diaphragm-type pneumatic actuator is preferably used, and the corresponding ground safety valve is a pneumatic diaphragm valve. This diaphragm-type pneumatic actuator has a diaphragm 30 and an upper cylinder 22 and a lower cylinder 16 for constructing the diaphragm cavity. The upper cylinder 22 and lower cylinder 16 are generally cylindrical structures, with the bottom of the upper cylinder 22 facing upwards and the bottom of the lower cylinder 16 facing downwards. The openings of the upper cylinder 22 and lower cylinder 16 are opposite each other, thus sealing the diaphragm cavity. The diaphragm 30 is located between the upper cylinder 22 and the lower cylinder 16, thereby dividing the diaphragm cavity into an upper diaphragm cavity 23 and a lower diaphragm cavity 17. This is a general structure of the diaphragm cavity in a pneumatic diaphragm valve, and will not be described in detail here.

[0066] The diaphragm 30 in the corresponding pneumatic diaphragm valve can be either single-acting or double-acting. Figure 3 The pneumatic diaphragm valve shown is a single-acting pneumatic diaphragm valve, that is, the compressed gas as the working gas acts on the diaphragm 30 only through the upper diaphragm chamber 23, and the reset of the diaphragm 30 is mainly achieved by the spring 15 shown in the figure.

[0067] The lower cylinder 16 has a lower intervention hole for the intervention of the valve stem 36. The valve stem 36 is inserted into the lower diaphragm cavity 17 through the lower intervention hole, and the upper end of the valve stem 36 is fixedly connected to the diaphragm 30.

[0068] The upper cylinder 22 has an upper intervention hole, through which the actuating part of the auxiliary actuator enters the upper diaphragm cavity 23 and is fixedly connected to the diaphragm 30.

[0069] exist Figure 3 In the illustrated structure, the cascade connector 28 is used for direct or indirect connection between the indicator rod 26 and the valve stem 36 illustrated in the figure.

[0070] In some embodiments, the diaphragm 30 has a central hole, and the connecting seat 28 can be constructed as a round-headed member with a screw, having a countersunk hole on its round head for connection with the indicator rod 26, the screw passing through the central hole for fixed connection with the upper spring support 32 illustrated in the figure. Accordingly, the upper spring support 32 has a threaded hole, under which condition the connecting seat 28 also serves as a fastener for fixing the upper spring support 32 to the diaphragm 30.

[0071] The upper spring support 32 is reused as a mounting base for the spring guide post, a spring seat at one end of the spring 15, and a base for connecting the valve stem 36 and the diaphragm 30.

[0072] The spring guide post is a form in which the valve stem 36 and the diaphragm 30 are indirectly connected, and in some embodiments, the length of the spring guide post can be adjusted, such as... Figure 3 The spring guide post is equipped with an adjustment component 34. Adjustment can be achieved based on the threaded connection between the two parts of the spring guide post, and then a set screw is used to lock the two parts of the threaded connection.

[0073] Regarding the diaphragm 30, diaphragms 30 used in ground safety valves are mostly metal diaphragms, which is common knowledge in this field and will not be elaborated further here. The diaphragm 30 is generally a circular sheet structure, and its periphery is generally clamped between the upper cylinder 22 and the lower cylinder 16. The upper cylinder 22 and the lower cylinder 16 are generally connected by a flange. The bolt group adapted to the flange connection is generally evenly distributed around the periphery of the diaphragm 30, and bolt holes are generally also opened around the periphery of the diaphragm 30.

[0074] In comparison, bolted connections are easy to loosen. In some implementations, the flange connection between the upper cylinder 22 and the lower cylinder 16 can also use rivets as fasteners. Riveting has relatively good reliability, but poor maintainability. If the diaphragm 30 needs to be replaced, the rivets need to be destroyed.

[0075] In a preferred embodiment, maintainability and reliability are taken into account, and in an even more preferred embodiment, a clamping method is used to achieve better assembly reliability.

[0076] Based on the flange connection, the lower cylinder body 16 has a lower flange 18 at the end that mates with the upper cylinder body 22, and the upper cylinder body 22 has an upper flange 19 at the end that mates with the lower cylinder body 16. The upper flange 19 may not have bolt holes and simply form an upper flange; similarly, the lower flange 18 may not have bolt holes and simply form a lower flange.

[0077] Furthermore, the upper cylinder 22 and the lower cylinder 16 are engaged, forming a convex ring around the periphery together with the diaphragm 30 they hold.

[0078] Provide as Figure 5 and Figure 6 The assembled ring component shown has a clamping groove on the inner side of the ring, such as... Figure 6 The slot 64 is located inside the left fixed ring 60 and the right fixed ring 61. The cross-section of the slot 64 can be a wedge-shaped slot or an isosceles trapezoidal slot, that is, the slot is wider closer to the opening. Thus, the upper cylinder body 22 and the lower cylinder body 16 are fastened by the constraint of the upper surface of the upper flange 19 and the lower surface of the lower flange 18 by the slot 64. And based on the narrowing of the combined annular part, the upper cylinder body 22 and the lower cylinder body 16 are reliably locked.

[0079] Figure 5 The illustrated combined ring component is a preferred embodiment of the combined ring component, which has two individual units, referred to as fixed ring 31, specifically a fan-ring structure, and the two individual fan-ring units are assembled into a combined ring component.

[0080] The central angle of each individual unit is not less than 175° and less than or equal to 180°. For distinction, the two units are referred to as the left fixed ring 60 and the right fixed ring 61, respectively; the two fan-shaped fixed rings 31 are joined together to form a ring structure.

[0081] It should be noted that assuming the central angles of both individual components are taken to their minimum value, i.e., 175°, does not affect the correct understanding that the assembled ring will form a ring. It should be understood that a ring in the mechanical field does not necessarily represent a perfect circle, much less a complete 360° circle. Using a fan-shaped ring with a central angle slightly less than 180° helps to overcome the problem of interference between the two individual components preventing further narrowing when assembling into a combined ring component. In other words, there is a certain amount of narrowing allowance between the two fixed rings 31.

[0082] Furthermore, referring to Figure 5 in the specification, each fixing ring 31 has an outwardly extending ear at each end, with a fixing hole on the ear. The ears of the two fixing rings 31 are arranged in parallel to ensure good coaxiality between the fixing holes on the ears.

[0083] Correspondingly, the fixing holes of the corresponding ears of the left fixing ring 60 and the right fixing ring 61 are aligned and connected by bolts 62 or screws. By tightening the bolts 62 or screws, the two fixing rings 31 are brought closer together, thereby producing a narrowing action.

[0084] In some embodiments, one of the two mounting holes used for mating is a threaded hole and the other is a smooth hole, with the screw inserted from the smooth hole side to connect with the threaded hole. In other embodiments, both mounting holes used for mating are smooth holes, so that the bolt 62 is used in conjunction with the nut 59 to achieve assembly between the two retaining rings 31.

[0085] When the cross-section of the clamping ring groove is an isosceles trapezoid or wedge, the surfaces of the upper and lower flanges that mate with the groove wall of the clamping ring groove can have the same slope as the groove wall. In this case, the contact area between the clamping ring groove and the two flanges is relatively large.

[0086] In other embodiments, the surfaces of the upper and lower flanges that mate with the groove wall of the clamping ring are parallel, and the mating surface between the clamping ring groove and the two flanges is relatively small.

[0087] Given that the diaphragm cavity needs to be sealed, therefore, in a more preferred embodiment, such as Figure 6 In the illustrated structure, a sealing ring 63 is provided within the clamp annular groove. The cross-section of the sealing ring 63 is also an isosceles trapezoidal or wedge-shaped structure to serve the two flanges of the clamp.

[0088] In some embodiments, O-rings may also be provided on the surfaces of the two flanges that mate with the diaphragm 30.

[0089] As mentioned above, the upper flange forms the upper flange 19 and the lower flange forms the lower flange 18. Under this condition, the upper cylinder body 22 and the lower cylinder body 16 can be connected by a flange while the clamp of the retaining ring 31 is used, thus achieving better reliability.

[0090] In some embodiments, since a single-acting mode is used, the upper diaphragm cavity 23 constitutes the working cavity and is connected to the compressed air source; if a double-acting mode is used, both the upper diaphragm cavity 23 and the lower diaphragm cavity 17 are connected to the compressed air source.

[0091] In some of the foregoing embodiments, it is indicated that the auxiliary actuator can act on the actuator of the pneumatic actuator through an indicator rod 26. That is, the indicator rod 26 can be a component of the aforementioned actuator or a component that indirectly interacts between the actuator and the actuator.

[0092] In some embodiments, the indicator rod 26 used for connecting the actuator and the valve stem 36 can be a virtual connection (joint connection) or a real connection (joint connection), each with its own advantages and disadvantages.

[0093] Accordingly, a connecting seat 24 is provided fitted into the upper intervention hole. The connecting seat 24 provides a guide hole through which the indicator rod 26 is guided, and a sealing assembly 25 is provided within the guide hole. In some embodiments, the indicator rod 26 may only act as a transmission component acting on the valve stem 36 as a secondary actuator. In a more preferred embodiment, the indicator rod 26 may also act as a detected component. Therefore, in some embodiments, a detection element is provided to detect the state of the indicator rod 26, thereby determining the activation timing of the secondary actuator according to a setting. For example, in the working state, the pneumatic actuator moves to lower the valve stem 36 to its position, thereby opening the ground safety valve. At this time, the indicator rod 26 follows the downward movement based on its connection with the diaphragm 30, and the portion of it exposed in the guide hole is correspondingly reduced.

[0094] If the upper diaphragm chamber 23 loses pressure, causing the diaphragm 30 to rise, thereby driving the indicator rod 26 to rise. The detection element is, for example, a limit switch. When the indicator rod 26 moves to a predetermined position and triggers the limit switch, it indicates that the ground safety valve is closed. This allows the auxiliary actuator to be activated, pushing the indicator rod 26 downward, thereby opening the ground safety valve.

[0095] In addition, when the limit switch is triggered, an alarm can be activated to facilitate the maintenance or repair of the ground safety valve that issued the alarm later.

[0096] Regarding the auxiliary actuator, it can be a component or mechanism that can directly output linear motion, such as an electric actuator. The electric actuator can be directly used as a component, and its actuator can directly provide linear motion output as an output component. It can be driven by engaging with the indicator rod 26, so that the electric actuator is in the reset state (i.e., the top dead center position) under normal conditions to avoid contact with the indicator rod 26.

[0097] Linear motors can also directly output linear motion, and can be used as a secondary option.

[0098] In some embodiments, the auxiliary actuator may also be configured with a rotary motor and a mechanism capable of converting rotary motion into linear motion, such as a lead screw mechanism. These embodiments are relatively complex, but offer relatively good stroke control flexibility.

[0099] Figure 4 In the structure shown, the motor 52 can be a rotary motor, which outputs a suitable speed through the reducer 51. It can drive the lead screw 43 through the coupling 48. The lead screw 43 is engaged with the lead screw nut, which drags a slide plate. The slide plate is used to drive the indicator rod 26.

[0100] exist Figure 4 The example structure uses a different form, which is clearly shown in the diagram and will not be elaborated upon here.

[0101] As mentioned above, the pneumatic actuator of the ground safety valve based on this utility model embodiment can be either single-acting or double-acting. If a single-acting actuator is used, a reset device is required. Figure 3 In the illustrated structure, spring 15 constitutes a component for resetting the diaphragm 30. Accordingly, in Figure 3 In the illustrated structure, the lower access port is fitted with a downwardly extending cylinder 33 for primarily housing the spring 15.

[0102] The cylinder 33 is equipped with a lower spring support 37 at its end to support the lower end of the spring 15; correspondingly, the diaphragm 30 is equipped with an upper spring support 32 on its lower surface to form the upper end of the spring 15.

[0103] Generally speaking, for pneumatic diaphragm valves, it is not necessary to further seal the valve stem 36. However, in the embodiments of this utility model, it is still chosen to further seal the valve stem 36 under the condition of using a pneumatic diaphragm valve structure.

[0104] See Figure 3 In the illustrated structure, a valve cover 12 is provided at the lower end of the cylinder 33, or in other words, the cylinder 33 is fixed to the valve body A by the valve cover 12.

[0105] like Figure 3As shown, the valve cover 12 in the figure includes a cover body and a sealing cylinder extending upward from the cover body. A packing seal structure is constructed inside the sealing cylinder, such as the packing seal 38 shown in the figure, and a packing gland 35 installed at the opening of the sealing cylinder, thereby providing a dynamic seal for the movable valve stem 36.

[0106] In addition, to improve the reliability of the assembly, as shown in Figure 3, the lower surface of the valve cover 12 has a tapered stop 39, which is used to seal with the actuation hole.

Claims

1. A dual-operation ground safety valve, characterized in that, include: The valve body has a valve cavity, and the valve body has an actuation hole on one side of the valve cavity; A valve plate, which mates with the valve chamber, is used for opening and closing a dual-operation ground safety valve; The valve stem enters the valve cavity through the actuation hole and is fixedly connected to the valve plate; A pneumatic actuator is mounted on the side of the valve body where the actuation hole is located to control the displacement of the valve plate; as well as A secondary actuator is mounted at the end of the pneumatic actuator away from the valve body. The actuating part of the secondary actuator is connected or engaged with the valve stem via the actuating element of the pneumatic actuator.

2. The dual-operation ground safety valve according to claim 1, characterized in that, The pneumatic actuator is a diaphragm pneumatic actuator, which includes: The lower cylinder has a lower intervention port for valve stem intervention; The upper cylinder body has an upper intervention port for intervention of the actuating part; and The diaphragm is sandwiched between the upper cylinder and the lower cylinder, forming an upper diaphragm cavity with the upper cylinder and a lower diaphragm cavity with the lower cylinder. The upper diaphragm cavity is connected to the compressed air source. The diaphragm is also connected to the actuating part and the valve stem.

3. The dual-operation ground safety valve according to claim 2, characterized in that, The lower cylinder block has a lower flange at the end where it mates with the upper cylinder block; The end where the upper cylinder block and the lower cylinder block meet has an upper flange; A combination of ring parts is provided, wherein the inner side of the ring of the combination of ring parts has a clamping ring groove; Accordingly, the upper flange and the lower flange combine to clamp the outer edge of the diaphragm to form a convex ring. The clamping ring groove of the combined annular part cooperates with the convex ring to further narrow and lock the mating upper cylinder and lower cylinder.

4. The dual-operation ground safety valve according to claim 3, characterized in that, The combined ring component includes two fixed rings with a central angle greater than or equal to 175° and less than or equal to 180°, referred to as the left fixed ring and the right fixed ring; Each end of the retaining ring has an outwardly extending ear with a retaining hole. Accordingly, the fixing holes of the corresponding ears of the left and right fixing rings are aligned and connected using bolts or screws.

5. The dual-operation ground safety valve according to claim 3 or 4, characterized in that, A sealing ring is provided inside the clamp ring groove.

6. The dual-operation ground safety valve according to claim 3 or 4, characterized in that, The upper flange forms an upper flange, and the lower flange forms a lower flange; Accordingly, the upper cylinder block and the lower cylinder block are assembled into a cylinder block by means of a flange connection.

7. The dual-operation ground safety valve according to claim 2, characterized in that, An indicator rod is provided for connecting the actuator to the valve stem; A connector is provided that is fitted into the upper intervention hole, the connector having a guide hole; The indicator rod is guided by the guide hole, and a sealing component is provided inside the guide hole; An additional detection element is provided to detect the state of the indicator rod, thereby determining the start-up timing of the auxiliary actuator.

8. The dual-operation ground safety valve according to claim 2 or 7, characterized in that, The auxiliary actuator is an electric push rod, a linear motor, or a rotary motor; If it is a rotary motor, a lead screw mechanism is provided to convert the rotary motion of the rotary motor into linear motion.

9. The dual-operation ground safety valve according to claim 2, characterized in that, The lower intervention port is fitted with a downwardly extending cylinder, the end of which is fitted with a spring-loaded lower support. Accordingly, the lower surface of the diaphragm is fitted with a spring-loaded upper support. A spring is provided between the upper support and the lower support of the spring for the reset of the diaphragm.

10. The dual-operation ground safety valve according to claim 9, characterized in that, The lower end of the cylinder is provided with a valve cover; the valve cover includes a cover body and an upwardly extending sealing cylinder; The lower surface of the valve cover has a tapered stop, which is used to seal with the actuation hole. The sealing cylinder is equipped with a packing seal assembly for dynamic sealing of the valve stem.

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