Wellhead pressure automatic control valve for oil and gas production

Abstract

The utility model discloses an oil and gas production wellhead pressure automatic control valve, which comprises a control valve, an oil and gas production wellhead pressure automatic control valve, an oil and gas production wellhead pressure automatic control valve and an oil and gas production wellhead pressure automatic control valve, the mechanical pressure sensor is connected with the control valve through different pipelines, the mechanical pressure sensor is used for being connected with fluid in a wellhead, the pipelines communicated with the control valve are switched according to different pressures of the connected fluid, and the control valve is controlled to be opened and closed. The valve has the advantages that the valve can be automatically controlled to be closed and opened only according to the underground pressure, for example, the valve is automatically closed when the underground pressure exceeds the designed pressure, and the valve is automatically opened to recover production operation when the underground pressure is lower than the designed pressure.

Description

Technical Field

[0001] The invention relates to an automatic control valve for oil and gas production wellhead pressure, belonging to the technical field of valves. Background Art

[0002] Wellhead pressure control valve is a common industrial valve, widely used in the oil and gas field. The wellhead pressure control valve of the prior art can automatically control the closing or opening of the valve through an external power source such as a hydraulic source, a pneumatic source or a power source. However, since the oil and gas wells are mostly located in remote areas, it is difficult or costly to provide a continuous power source for the automatic control valve switch. For example, a ground emergency shut-off valve with an accumulator that is currently in common use can only use the energy provided by the control system to achieve several emergency shut-offs, and after each shut-off, it cannot automatically open for production when the wellhead pressure returns to normal, and needs to be manually opened again for production. Although the control flexibility of the electric control valve is relatively high, on the one hand, there is a lack of power sources in remote areas, and on the other hand, the fluids in the oil and gas production process are flammable and explosive, and contact with the electronic control system that is prone to sparks or static electricity can easily cause safety hazards. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide an automatic control valve for oil and gas production wellhead pressure.

[0004] In order to solve the above technical problems, the present invention is implemented by adopting the following technical solutions.

[0005] In one aspect, the present invention discloses an automatic control valve for oil and gas production wellhead pressure, comprising:

[0006] Control valve, installed at the oil and gas production wellhead, used to control the opening and closing of the production wellhead;

[0007] The mechanical pressure sensor is connected to the control valve through different pipelines. The mechanical pressure sensor is used to access the fluid in the wellhead, switch the pipeline connected to the control valve according to the pressure of the accessed fluid, and control the opening and closing of the control valve.

[0008] Further, the control valve comprises a cylinder, a piston, a valve stem, a valve plate and a valve body;

[0009] The piston is arranged in the cylinder body, dividing the cylinder body into an upper cylinder and a lower cylinder with variable upper and lower spaces. The upper end of the valve stem is connected to the piston, and the lower end is connected to the valve plate. The valve plate is used to control the opening and closing of the internal channel of the valve body.

[0010] Furthermore, the upper cylinder and the lower cylinder are both provided with a pressure relief valve.

[0011] Furthermore, the control valve further comprises a manual valve opening screw and a balance rod, and the valve body is provided with a manual valve opening through hole;

[0012] The balance rod is movably arranged in the manual valve opening through hole. When the valve is manually opened, the upper end of the manual valve opening screw abuts against the lower end of the balance rod, and the upper end of the balance rod abuts against the lower end of the valve plate.

[0013] Furthermore, the control valve also includes a grease injection valve, a packing group and a packing pressure cap;

[0014] The grease injection valve is a one-way valve connected to the manual valve opening through hole and is used for injecting sealing grease; the packing group is tightly connected to the balance rod, and the packing pressure cap fixes the packing group.

[0015] Further, the mechanical pressure sensor includes a sensor body, a spring, a sensor valve core, an open valve pressure inlet O, a closed valve pressure inlet C, an upper discharge hole R1, a pipeline pressure inlet P, a lower discharge hole R2 and a sensor drive pressure port Q;

[0016] The sensor body is provided with a cavity inside, the spring is arranged on the upper part of the cavity, the lower end of the spring is connected to the sensor valve core, and the sensor body is provided with the valve opening pressure inlet O, the valve closing pressure inlet C, the upper discharge hole R1, the pipeline pressure inlet P and the lower discharge hole R2;

[0017] The open valve pressure inlet O is connected to the lower cylinder by opening the well pressure pipeline, the closed valve pressure inlet C is connected to the upper cylinder by closing the well pressure pipeline, and the pipeline pressure inlet P is connected to the fluid;

[0018] The sensor valve core is acted upon by the combined pressure of the spring and the fluid input from the sensor driving pressure port Q, and controls the sensor valve core to enter the first control state and the second control state;

[0019] The sensor valve core in the first control state keeps the pipeline pressure access port P in communication with the open valve pressure inlet port O, and closes the pressure inlet port C in communication with the lower discharge hole R2;

[0020] The sensor valve core in the second control state keeps the pipeline pressure access port P in communication with the closed pressure inlet port C, and the upper discharge hole R1 in communication with the open valve pressure inlet port O.

[0021] Furthermore, it also includes a four-way stop valve, the four ports of which are respectively connected to a pressure gauge, a valve body through hole, a pipeline pressure access port P and a sensor drive pressure port Q; the valve body through hole is a port opened on the valve body and is used to output the fluid in the wellhead; the four-way stop valve is provided with a stop valve handle for opening and closing the four-way stop valve.

[0022] Furthermore, the sensor valve core is provided with a valve core sealing ring.

[0023] Furthermore, the mechanical pressure sensor also includes a pressure regulating cap and a floating pressure block, the lower end of the floating pressure block is fixed to the upper end of the spring, the upper end of the floating pressure block abuts against the lower end of the pressure regulating cap, and the pressure regulating cap is threadedly connected to the upper part of the sensor body.

[0024] Furthermore, the lower end of the spring is connected to a spring seat, and the spring seat is connected to the upper end of the sensor valve core.

[0025] The beneficial effects achieved by the present invention are:

[0026] The valve of the present invention can automatically control the closing and opening of the valve according to the size of the downhole pressure. For example, when the downhole pressure exceeds the design pressure, the valve automatically closes, and when the downhole pressure is lower than the design pressure, the valve automatically opens to resume production operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0028] Figure 2 It is a schematic diagram of the structure of the mechanical sensor of the present invention;

[0029] Figure 3 The present invention Figure 1 A-direction schematic diagram in FIG.

[0030] Figure 4 It is a schematic diagram of the principle of the present invention. DETAILED DESCRIPTION

[0031] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0032] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0034] Embodiment 1, as Figure 1 As shown, this embodiment introduces an automatic control valve for oil and gas production wellhead pressure, comprising:

[0035] Control valve 1, installed at the oil and gas production wellhead, used to control the opening and closing of the production wellhead;

[0036] The mechanical pressure sensor 2 is connected to the control valve 1 through different pipelines. The mechanical pressure sensor 2 is used to access the fluid in the wellhead, switch the pipeline connected to the control valve 1 according to the pressure of the accessed fluid, and control the opening and closing of the control valve 1.

[0037] The control valve 1 includes a cylinder body 11, a piston 12, a valve stem 13, a valve plate 14 and a valve body 15; the piston 12 is arranged in the cylinder body 11, dividing the cylinder body 11 into an upper cylinder and a lower cylinder with variable upper and lower spaces, the upper end of the valve stem 13 is connected to the piston 12, and the lower end is connected to the valve plate 14, and the valve plate 14 is used to control the opening and closing of the internal channel of the valve body 15.

[0038] The upper cylinder and the lower cylinder are both provided with a pressure relief valve 16 for releasing the pressure in the upper cylinder and the lower cylinder of the cylinder body when the mechanical pressure sensor 2 needs to be repaired or replaced.

[0039] The control valve 1 further comprises a manual valve opening screw 17 and a balance rod 18, and the valve body 15 is provided with a manual valve opening through hole;

[0040] The balance rod 18 is movably arranged in the manual valve opening through hole. When the valve is manually opened, the upper end of the manual valve opening screw 17 abuts against the lower end of the balance rod 18, and the upper end of the balance rod 18 abuts against the lower end of the valve plate 14; when the control valve 1 is in a closed state, if the pressure suddenly drops very low and this pressure is less than the pressure of opening the control valve 1 by the mechanical pressure sensor 2 (the pressure value can be displayed by the pressure gauge), if the control valve 1 needs to be opened at this time, it is necessary to use the manual valve opening screw 17 to rotate inward and move it upward against the balance rod to fully open the valve.

[0041] The control valve 1 further comprises a grease injection valve 19, a packing group 110 and a packing pressing cap 111;

[0042] The grease injection valve 19 is a one-way valve, which is connected to the manual valve opening hole and is used for injecting sealing grease; the packing group 110 is tightly connected to the balance rod 18, and the packing pressure cap 111 fixes the packing group; the grease injection valve can inject sealing grease into the valve cavity in a one-way manner; the packing group is used to seal the balance rod 18, and the packing pressure cap presses the packing group to prevent it from being pushed out by pressure.

[0043] like Figure 1 , Figure 2 and Figure 4 As shown, the mechanical pressure sensor 2 includes a sensor body 21, a spring 22 (high-strength spring), a sensor valve core 23, an open valve pressure inlet O24 (normally open state), a closed valve pressure inlet C25 (normally closed state), an upper discharge hole R126, a pipeline pressure inlet P27, a lower discharge hole R228 and a sensor drive pressure port Q29;

[0044] The sensor body 21 has a cavity inside, the spring 22 is arranged on the upper part of the cavity, the lower end of the spring 22 is connected to the sensor valve core 23, and the sensor body 21 is provided with the valve opening pressure inlet O24, the valve closing pressure inlet C25, the upper discharge hole R126, the pipeline pressure inlet P27 and the lower discharge hole R228;

[0045] The open valve pressure inlet O24 is connected to the lower cylinder by opening the well pressure pipeline 31, the closed valve pressure inlet C25 is connected to the upper cylinder by closing the well pressure pipeline 32, and the pipeline pressure inlet P27 is connected to the fluid;

[0046] The sensor valve core 23 is acted upon by the combined pressure of the spring 22 and the fluid input from the sensor driving pressure port Q29, and controls the sensor valve core 23 to enter the first control state and the second control state;

[0047] The sensor valve core 23 in the first control state keeps the pipeline pressure access port P27 connected to the open valve pressure inlet port O24, and closes the pressure inlet port C25 connected to the lower discharge hole R228;

[0048] The sensor valve core in the second control state keeps the pipeline pressure access port P27 connected to the closed pressure inlet port C25, and the upper discharge hole R126 connected to the open valve pressure inlet port O24.

[0049] Automatic opening process of fluid pressure: The valve is installed on the gas production wellhead, and the initial state should keep the valve fully open or fully closed. When the pressure passing through the valve flow channel hole is below the setting of the mechanical pressure sensor, the high-strength spring remains in the initial state to push the valve core down, keeping the pipeline pressure access port P connected to the valve opening pressure inlet O, and the fluid pressure enters the lower part of the valve hydraulic cylinder, causing the plug to move upward under force and drive the valve plate to move to the upper position (fully open position). During this process, if there is pressure in the upper hydraulic cylinder, it will be discharged to the recovery barrel 5 by connecting the lower discharge hole R2 through the closed pressure inlet pipeline to the closed pressure inlet C of the mechanical sensor.

[0050] Fluid pressure automatic closing process: When the pressure flowing through the flow channel hole of the valve installed on the gas production wellhead exceeds the pressure set by the mechanical sensor, the fluid pressure will compress the high-strength spring upward and move the valve core upward until the pipeline pressure access port P is connected to the closed pressure inlet port C, and the upper discharge hole R1 is connected to the open valve pressure inlet port O. At this time, the fluid pressure will enter the upper hydraulic cylinder of the valve through the pipeline from the pipeline pressure access port P and the closed pressure inlet port C. At the same time, the lower hydraulic cylinder of the valve will discharge the original pressure in the cylinder from the open valve pressure inlet port O and the upper discharge hole R1 to the recovery barrel 5 through the pipeline, so that the piston moves downward to drive the valve plate downward until it is closed.

[0051] The sensor valve core 23 is provided with a valve core sealing ring 210 to play a sealing role and prevent the sensor valve core 23 from leaking from the side.

[0052] The mechanical pressure sensor 2 further comprises a pressure regulating cap 211 and a floating pressure block 212, wherein the lower end of the floating pressure block 212 is fixed to the upper end of the spring 22, the upper end of the floating pressure block 212 is in contact with the lower end of the pressure regulating cap 211, the lower end of the spring is connected to a spring seat 213, the spring seat 213 is connected to the upper end of the sensor valve core, the pressure regulating cap 211 is threadedly connected to the upper part of the sensor body 21, and the pressure regulating cap is adjusted through the thread on the outer side of the upper end of the sensor body, thereby adjusting the preload force of the spring 22 to achieve the setting of the sensing pressure of the mechanical pressure sensor 2; thus, the pressure setting of the mechanical sensor 2 can be achieved by replacing the high-strength spring and rotating the pressure regulating cap 211. The sensor driving pressure port Q is connected to the downhole pressure, when the pressure is less than the spring force, the valve core is in the lower position, and when the downhole pressure is higher than the spring force, the spring is compressed and the valve core moves to the upper position.

[0053] Example 2 is based on the same inventive concept as Example 1. This example introduces an automatic control valve for oil and gas production wellhead pressure. The difference between this example and Example 1 is that: Figure 1 and Figure 3 As shown, it also includes a four-way stop valve 3, the four ports of the four-way stop valve 3 are respectively connected to the pressure gauge 4, the valve body through hole 112, the pipeline pressure access port P and the sensor drive pressure port Q, the valve body through hole 112 is a port opened on the valve body 15, and is used to output the fluid in the wellhead; the four-way stop valve 3 is provided with a stop valve handle 31 for opening and closing the four-way stop valve 3; when the four-way stop valve 3 is closed and the pressure in the cylinder is released through the pressure relief valve 16, the mechanical sensor 2 can be maintained or replaced, and a pressure gauge 4 is connected to the four-way stop valve 3 to monitor the downhole pressure in real time.

[0054] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An automatic control valve for oil and gas production wellhead pressure, characterized in that: include: Control valve, installed at the oil and gas production wellhead, used to control the opening and closing of the production wellhead; A mechanical pressure sensor is connected to the control valve through different pipelines. The mechanical pressure sensor is used to access the fluid in the wellhead and switch the pipeline connected to the control valve according to the pressure of the accessed fluid to control the opening and closing of the control valve; The control valve comprises a cylinder body, a piston, a valve stem, a valve plate and a valve body; the piston is arranged in the cylinder body, dividing the cylinder body into an upper cylinder and a lower cylinder with variable upper and lower spaces; the upper end of the valve stem is connected to the piston, and the lower end is connected to the valve plate, and the valve plate is used to control the opening and closing of the internal channel of the valve body; The mechanical pressure sensor comprises a sensor body, a spring, a sensor valve core, an open valve pressure inlet O, a closed valve pressure inlet C, an upper discharge hole R1, a pipeline pressure inlet P, a lower discharge hole R2 and a sensor drive pressure port Q; The sensor body is provided with a cavity inside, the spring is arranged on the upper part of the cavity, the lower end of the spring is connected to the sensor valve core, and the sensor body is provided with the valve opening pressure inlet O, the valve closing pressure inlet C, the upper discharge hole R1, the pipeline pressure inlet P and the lower discharge hole R2; The open valve pressure inlet O is connected to the lower cylinder by opening the well pressure pipeline, the closed valve pressure inlet C is connected to the upper cylinder by closing the well pressure pipeline, and the pipeline pressure inlet P is connected to the fluid; The sensor valve core is acted upon by the combined pressure of the spring and the fluid input from the sensor driving pressure port Q, and controls the sensor valve core to enter the first control state and the second control state; The sensor valve core in the first control state keeps the pipeline pressure access port P in communication with the open valve pressure inlet port O, and closes the pressure inlet port C in communication with the lower discharge hole R2; The sensor valve core in the second control state keeps the pipeline pressure access port P in communication with the closed pressure inlet port C, and the upper discharge hole R1 in communication with the open valve pressure inlet port O.

2. The automatic control valve for oil and gas production wellhead pressure according to claim 1, characterized in that: The upper cylinder and the lower cylinder are both provided with pressure relief valves.

3. The automatic control valve for oil and gas production wellhead pressure according to claim 1, characterized in that: The control valve also includes a manual valve opening screw and a balance rod, and the valve body is provided with a manual valve opening through hole; The balance rod is movably arranged in the manual valve opening through hole. When the valve is manually opened, the upper end of the manual valve opening screw abuts against the lower end of the balance rod, and the upper end of the balance rod abuts against the lower end of the valve plate.

4. The automatic control valve for oil and gas production wellhead pressure according to claim 3, characterized in that: The control valve also includes a grease injection valve, a packing group and a packing pressure cap; The grease injection valve is a one-way valve connected to the manual valve opening through hole and is used for injecting sealing grease; the packing group is tightly connected to the balance rod, and the packing pressure cap fixes the packing group.

5. The automatic control valve for oil and gas production wellhead pressure according to claim 1, characterized in that: It also includes a four-way stop valve, the four ports of which are respectively connected to a pressure gauge, a valve body through hole, a pipeline pressure access port P and a sensor drive pressure port Q; the valve body through hole is a port opened on the valve body and is used to output the fluid in the wellhead; the four-way stop valve is provided with a stop valve handle for opening and closing the four-way stop valve.

6. The automatic control valve for oil and gas production wellhead pressure according to claim 1, characterized in that: The sensor valve core is provided with a valve core sealing ring.

7. The automatic control valve for oil and gas production wellhead pressure according to claim 1, characterized in that: The mechanical pressure sensor also includes a pressure regulating cap and a floating pressure block, the lower end of the floating pressure block is fixed to the upper end of the spring, the upper end of the floating pressure block abuts against the lower end of the pressure regulating cap, and the pressure regulating cap is threadedly connected to the upper part of the sensor body.

8. The automatic control valve for oil and gas production wellhead pressure according to claim 7, characterized in that: The lower end of the spring is connected to a spring seat, and the spring seat is connected to the upper end of the sensor valve core.

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