Repeatable automatic sealing valve for underground oil pipe

Abstract

The repeatable automatic sealing valve comprises a central pipe, the left end of the central pipe is rotationally connected with a sealing plate, a valve reset control mechanism is further arranged on the outer side of the central pipe, and a cam mechanism is arranged at the rotating position of the valve reset control mechanism and the sealing plate; the valve reset control mechanism resets the sealing plate through the cam mechanism. According to the equipment provided by the embodiment of the invention, when the butt joint pipe column is pulled out, the closed valve automatically turns over under the action of the control mechanism, an oil pipe channel is rapidly closed, and fluid below the packer is controlled to flow upwards. And when the sealing butt-joint pipe column can be repeatedly and automatically connected with the oil pipe in a sealing manner, the through rod forces the valve plate to turn over to keep an open state. The operation period of a water injection well is effectively shortened, the water injection time rate is improved, the under-pressure operation cost is high, and the sewage treatment cost after water well pressure relief is high.

Description

Technical Field

[0001] The present application relates to the technical field of oil extraction, and in particular to a repeatable automatic sealing valve for a downhole oil pipe. Background Art

[0002] During the development of oil fields, as oil wells are continuously mined, production declines severely. Water injection is often used to increase reservoir pressure to replenish energy and improve recovery. When water injection wells are to be operated, well pressure reduction or pressure relief is generally used to reduce pressure. Due to the high water injection pressure of some wells, the pressure relief cycle is long during operation and the cost of sewage treatment is high. The energy replenishment process after water injection is restored is long and costly, and it will also cause pollution to the formation. Therefore, we proposed a repeatable automatic sealing valve for downhole oil pipes. Summary of the invention

[0003] The present application provides a downhole oil pipe repeatable automatic sealing valve to solve the problems raised in the above background technology.

[0004] In order to solve the above technical problems or at least partially solve the above technical problems, the present application provides a downhole oil pipe repeatable automatic sealing valve, comprising:

[0005] A central tube, the left end of which is rotatably connected to a sealing plate, a valve reset control mechanism is also provided on the outer side of the central tube, a cam mechanism is provided at the rotation point between the valve reset control mechanism and the sealing plate, and the valve reset control mechanism resets the sealing plate through the cam mechanism.

[0006] Optionally, the central tube is arranged inside the cylinder.

[0007] Optionally, the valve reset control mechanism is arranged between the outer side of the central tube and the inner side wall of the cylinder.

[0008] Optionally, the valve reset control mechanism consists of a piston and a spring, the piston is sealingly slidably arranged between the outer side of the central tube and the inner side wall of the cylinder, the right end of the piston is provided with the spring, and the spring is sleeved on the outer side of the central tube.

[0009] Optionally, a first spring seat and a second spring seat are respectively provided on the right side of the outer portion of the central tube and the right side of the piston, and the spring is clamped between the first spring seat and the second spring seat.

[0010] Optionally, the left side of the piston is movably engaged in the limiting groove of the cam mechanism.

[0011] Optionally, an adjustment ring is provided on the outer side of the central tube on the right side of the first spring seat, and adjustment bolts are threadedly inserted in an annular array on the adjustment ring.

[0012] Optionally, a lower joint is threadedly connected to the left side of the cylinder.

[0013] Optionally, an upper joint is threadedly inserted into the right side of the cylinder, and the interior of the upper joint is fixedly inserted into the right side of the central tube.

[0014] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0015] The device provided in the embodiment of the present application, when the butt-joint pipe column is pulled out, the closed valve automatically flips under the action of the control mechanism, quickly closes the oil pipe channel, and controls the upward flow of the fluid below the packer. When the sealed butt-joint pipe column is connected to the oil pipe again, the through rod forces the valve plate to flip and keep it open. It effectively reduces the operation cycle of the water injection well and improves the water injection time rate, the high cost of pressure operation, and the high cost of sewage treatment after the water well is depressurized. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0018] Figure 1 The present invention is a cross-sectional view of a repeatable automatic sealing valve for a downhole oil pipe.

[0019] In the figure: 1, upper joint; 2, center tube; 3, adjusting bolt; 4, spring; 5, piston; 6, sealing plate; 7, cylinder; 8, lower joint; 9, cam mechanism; 10, second spring seat; 11, first spring seat. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0021] Various embodiments of the present application may exist in the form of a range. It should be understood that the description in the form of a range is only for convenience and simplicity and should not be understood as a hard limit to the scope of the present application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single values ​​within the range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which are applicable regardless of the range. In addition, whenever a numerical range is indicated in the present application, it is meant to include any quoted numbers (fractions or integers) within the indicated range. Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present application, etc., can be purchased from the market or can be prepared by existing methods.

[0022] In the present application, in the absence of any contrary description, the directional words used, such as "upper" and "lower", are specifically the directions of the drawings in the accompanying drawings. In addition, in the present application, the terms "include", "comprise", etc. refer to "including but not limited to". In the present application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In the present application, "and / or" describes the association relationship of the associated objects, indicating that three relationships may exist, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. Wherein A, B can be singular or plural. In the present application, "at least one" refers to one or more, and "plural" refers to two or more. "At least one", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of singular items or plural items. For example, "at least one of a, b, or c" or "at least one of a, b and c" can both mean: a, b, c, ab, i.e. a and b, ac, bc or abc, where a, b, c can be single or plural, respectively.

[0023] like Figure 1 As shown, the embodiment of the present application provides a downhole oil pipe repeatable automatic sealing valve, comprising:

[0024] The center tube 2 is arranged inside the cylinder 7, and the left end of the center tube 2 is rotatably connected to the sealing plate 6. A valve reset control mechanism is also provided on the outside of the center tube 2. A cam mechanism 9 is provided at the rotation point between the valve reset control mechanism and the sealing plate 6. The valve reset control mechanism resets the sealing plate 6 through the cam mechanism 9.

[0025] Specifically, the cam mechanism 9 will rotate with the rotation of the sealing plate 6. When the cam mechanism 9 rotates, it will drive the piston 5 to move to the right. The right side of the sealing plate 6 is truncated cone-shaped. The left end side wall of the center tube 2 cooperates with the sealing plate 6 to provide an inward inclined surface to increase the sealing degree of the sealing plate 6.

[0026] like Figure 1 As shown: the valve reset control mechanism is arranged between the outer side of the central tube 2 and the inner side wall of the cylinder 7.

[0027] The valve reset control mechanism is composed of a piston 5 and a spring 4. The piston 5 is sealingly and slidably arranged between the outer side of the central tube 2 and the inner side wall of the cylinder 7. The right end of the piston 5 is provided with the spring 4, and the spring 4 is sleeved on the outer side of the central tube 2.

[0028] Specifically, the spring 4 is always in a compressed state, thereby exerting a force on the piston 5 , so that when the sealing plate 6 is not subjected to external force, the sealing plate 6 will be squeezed by the rotation of the cam mechanism 9 so as to seal the left end of the central tube 2 .

[0029] like Figure 1 As shown, a first spring seat 11 and a second spring seat 10 are respectively disposed on the outer right side of the central tube 2 and the right side of the piston 5 , and the spring 4 is clamped between the first spring seat 11 and the second spring seat 10 .

[0030] Specifically, the first spring seat 11 and the second spring seat 10 can make the spring 4 more stable when being compressed.

[0031] like Figure 1 As shown: the left side of the piston 5 is movably engaged in the limiting groove of the cam mechanism 9.

[0032] Specifically, the cam mechanism 9 adopts the existing cam mechanism 9 on the market. The rotation of the cam mechanism 9 can drive the piston 5 to move, thereby squeezing the spring 4 and providing a force for the resetting seal of the sealing plate 6.

[0033] like Figure 1 As shown, an adjustment ring is provided on the outer side of the central tube 2 on the right side of the first spring seat 11, and an adjusting bolt 3 is threadedly inserted in an annular array on the adjustment ring.

[0034] Specifically, the adjusting ring can slide on the outside of the central tube 2, and the adjusting bolt 3 can locate the position of the adjusting ring when it is tightened.

[0035] like Figure 1 As shown: the left side of the cylinder 7 is connected with a lower joint 8 through a thread; the right side of the cylinder 7 is connected with an upper joint 1 through a thread, and the inside of the upper joint 1 is fixedly connected with the right side of the central tube 2.

[0036] Specifically, the upper joint 1 can position and fix the central pipe 2 .

[0037] Furthermore, the interior of the lower connector 8 may be provided with threads to facilitate connection with external equipment.

[0038] When the equipment is in use, the upper joint 1 plays a fixing role, is located at the top and is connected to the outer end connector of the lower part of the isolation packer, and the main channel inside a central tube 2 is a large channel; the central tube 2 plays an insertion guide role and is also a large diameter for pressure relief or injection into a single flow channel, the lower part of the central tube 2 is connected to a closed plate 6, a lower sealing plate 6, which plays a sealing role and is connected and fixed with a cam mechanism 9; the outside of the central tube 2 is a valve reset control mechanism, which relies on adjusting the position of the adjusting ring and fixing its position through the adjusting bolt 3, thereby adjusting the force of the spring 4; relying on the elastic reset of the spring 4 itself, the push The movable piston 5 and the cam mechanism 9 drive the sealing plate 3 to automatically flip over, which plays a role in closing the injection channel. In the normal state, the sealing plate 6 closes the inner channel. When injecting water, the sealing plate 6 is pressed down by the lower insertion tube mechanism, and the sealing plate 6 flips over. The cam mechanism 9 pushes the piston 5 to move, and the compression spring 4 is displaced to open the channel, thereby satisfying the water injection or rapid pressure relief function, and when the sealing plate 6 is not subjected to external force, the force of the spring 4 will drive the piston 5 to move to the left and drive the cam mechanism 9 to rotate, so that the sealing plate 6 rotates to seal the central tube 2, and the lower joint 8 plays the function of fixing and liquid channel.

[0039] Taking the rapid pressure relief operation of a water injection well as an example, the present invention is further described in detail.

[0040] During the on-site construction process, the pipe string is lowered into the well, and the packer and the sealing valve are sealed at the upper part of the production layer, and the hands are released; the bottom of the water injection pipe string is equipped with a through rod, and the sealing plug of the long sealing section is lowered into the well, plugged and sealed with the center pipe of the packer, and the high pressure in the reservoir is controlled at the lower part of the packer. The through rod pushes the sealing plate 3. Under the action of the control mechanism, the through rod forces the sealing plate 6 to flip, and the oil pipe channel is opened. The channel diameter is large to prevent the accumulation of debris.

[0041] When the inspection operation is needed, the pipe string is lifted 2m, and the through rod is lifted out of the central pipe 2. The sealing plate 6 is automatically turned over by the control mechanism, and the sealing valve is automatically closed to prevent the oil pipe channel from flowing out. The sealing valve controls the pressure in the reservoir at the bottom of the packer, thereby realizing the casing environmental pressure control, and thus realizing the oil well snubbing operation. After confirming that there is no pressure, the pipe string is pulled out.

[0042] At this time, the fluid in the reservoir can be controlled at the bottom of the packer, so that the reservoir pressure system is not affected by the operation in the wellbore. The advantages of this closed valve are that it can be reused, opening and closing are not affected by reservoir pressure, it has a long effective period and is corrosion-resistant.

[0043] The control structure of the oil pipe repeatable automatic sealing valve is simple and practical. During the working process, no matter the oil pipe channel is closed or open, the operation pipe can effectively prevent the accumulation of debris and blockage of the injection channel during the injection process. It can achieve water well operation without well pressure reduction, avoid formation pollution and prevent the flow from top to bottom, and prevent foreign fluids, impurities and organic matter from leaking into the reservoir during the operation to cause pollution, thus protecting the reservoir; it can also close the channel to avoid a long pressure relief cycle of the water injection well, and the return of injected water to reduce the water injection rate; this tool is easy to install and has a wide range of adaptability while meeting the needs of various operating environments, which greatly meets the current needs of new and old oil field operations.

[0044] Example:

[0045] Chinese Patent: Downhole constant pressure opening injection, production, and well washing valve, Publication No. CN201068781Y, the utility model relates to a downhole constant pressure opening injection, production, and well washing valve. It is composed of a fishing head, a flow cap, a ball, a valve body, a plunger rod, a piston, a spring, a sealing plug, an anti-loosening pressure cap, and a sealing O-ring. The valve body is composed of two symmetrical plunger cylinders, a one-way oil production channel, an injection channel, a valve cylinder, and threads at both ends. The valve is a drop-in injection, production, and well washing valve, and its working state is that the sealing plug is inserted into the fish top sealing cavity in the well, and the liquid below the sealing cavity can be produced through the valve. It is normally open from bottom to top, and it is opened at a constant pressure from top to bottom. Therefore, it can be achieved that when washing the well in the space above the sealing cavity, the washing liquid will not be injected into the space below the sealing cavity, and when it is necessary to process the space below the sealing cavity, it can be opened at the designed pressure to squeeze liquid into the space below the sealing cavity.

[0046] Chinese Patent: A Sealed Valve, Publication No. CN219198155U, the utility model provides a sealed valve, the sealed valve comprises a valve frame with a valve port, a valve body protruding from the inner wall of the valve frame to the middle, a valve plate for abutting against the valve body to close the valve port, a sealing ring arranged around the valve plate, the end of the valve body away from the valve frame is formed with an inner conical surface, the inner conical surface extends obliquely from the side close to the valve plate toward the side away from the valve plate toward the center, and the edge of the sealing ring is inclined to form an outer conical surface to abut against the inner conical surface. The sealed valve of the utility model improves the sealing effect and prolongs the service life by arranging the inner conical surface on the valve body.

[0047] Chinese Patent: A push-pull type closed valve, publication number CN218815914U, the utility model relates to the technical field of civil air defense engineering construction, and discloses a push-pull type closed valve, including a closed body, the closed body including a weight block, a closing component is movably installed inside the closed body, a starting component is also fixedly installed on the inner side of the closing component, a transmission component is fixedly installed on the outer side of the starting component and on the surface of the closing component, a sliding component is fixedly installed on the bottom of the transmission component, and an independent power supply is fixedly installed on one side of the sliding component; this push-pull type closed valve is provided with a closing component, a starting component, and a transmission component, which is conducive to realizing the rapid closure of the device in an emergency, ensuring that the device is smoothly isolated from the influence of the external environment, shortening the closing time, and improving the use experience. By providing a sliding component, it is conducive to improving the operation mode of the device, improving the practicality of the actual use of the device, increasing the service life of the device, better facing the occurrence of emergencies, and increasing the safety of the device.

[0048] Chinese Patent: Completion string for protecting reservoirs of oil and gas wells, Publication No. CN209670950U, The utility model discloses a completion string for protecting reservoirs of oil and gas wells, including an upper string and a lower string, wherein the upper string includes a tubing hanger, an upper tubing, a pressure control valve and a sealing insert connected in sequence, and the lower string includes a packer, a multiple-opening valve, a core storage tube, a buffer tube and a round-head guide shoe connected in sequence through the lower tubing, the packer is sleeved outside the sealing tube, and the lower section of the sealing insert is sealed and plugged into the sealing tube from top to bottom. The utility model provides multiple-opening valves and cooperates with the pressure control valve, the core storage tube and the buffer tube, so that the entire completion string has the function of closing and opening the oil and gas production channel, and realizes the isolation of the working fluid and the reservoir during the entire operation process of the well repair operation, thereby effectively protecting the reservoir, preventing reservoir pollution, and significantly reducing production losses.

[0049] Chinese Patent: Valve plate type formation protection device for underground operation, publication number CN212774226U, the utility model discloses a valve plate type formation protection device for underground operation, characterized in that it includes an upper joint, a valve seat, a tightening sleeve, a valve plate chamber, a torsion spring, a valve plate assembly and a guide shoe, the upper joint and the guide shoe are fixedly connected, the valve seat is fixedly connected to the inner wall of the upper joint, a tightening sleeve and a valve plate chamber are arranged between the valve seat and the guide shoe, the inner wall of the tightening sleeve is respectively fixedly connected to the outer wall of the valve seat and the outer wall of the valve plate chamber, the valve plate chamber, the torsion spring and the valve plate assembly are connected by pins, the valve plate assembly includes a valve plate, a piston and a leaf spring, a pressure balance hole is through-set on the valve plate, the piston is arranged in the pressure balance hole through the leaf spring, the piston is sealed with the pressure balance hole, and the valve plate is sealed with the valve seat under the action of the torsion spring. By adopting the utility model, the packer can effectively isolate the reservoir in the lower part of the wellbore after being set, reduce the wellhead pressure, reduce the use of well killing fluid, reduce the pollution of the reservoir by the wellbore fluid in each operation stage, protect the formation and reduce the processing cost in the operation and production process after commissioning.

[0050] According to the above-mentioned published information, the oil and water well construction operation methods are all methods of well killing or pressure operation, which are different from the present invention in terms of method and principle.

[0051] The above is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. It will be apparent to those skilled in the art that various modifications to these embodiments are possible, and the general principles defined in the present application can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown in the present application, but will conform to the widest scope consistent with the principles and novel features applied for by the present application.

Claims

1. A downhole oil pipe repeatable automatic sealing valve, characterized in that: include: A central tube (2), the left end of the central tube (2) being rotatably connected to a sealing plate (6), a valve reset control mechanism being further provided on the outer side of the central tube (2), a cam mechanism (9) being provided at the rotational position between the valve reset control mechanism and the sealing plate (6), and the valve reset control mechanism resets the sealing plate (6) via the cam mechanism (9).

2. The downhole oil pipe repeatable automatic sealing valve according to claim 1, characterized in that: The central tube (2) is arranged inside the cylinder (7).

3. The downhole oil pipe repeatable automatic sealing valve according to claim 1, characterized in that: The valve reset control mechanism is arranged between the outer side of the central tube (2) and the inner side wall of the cylinder (7).

4. The downhole oil pipe repeatable automatic sealing valve according to claim 3, characterized in that: The valve reset control mechanism is composed of a piston (5) and a spring (4). The piston (5) is sealingly slidably arranged between the outer side of the central tube (2) and the inner side wall of the cylinder (7). The right end of the piston (5) is provided with the spring (4), and the spring (4) is sleeved on the outer side of the central tube (2).

5. The downhole oil pipe repeatable automatic sealing valve according to claim 4, characterized in that: A first spring seat (11) and a second spring seat (10) are respectively provided on the right side of the outside of the central tube (2) and the right side of the piston (5), and the spring (4) is clamped between the first spring seat (11) and the second spring seat (10).

6. The downhole oil pipe repeatable automatic sealing valve according to claim 5, characterized in that: The left side of the piston (5) is movably engaged in the limiting groove of the cam mechanism (9).

7. The downhole oil pipe repeatable automatic sealing valve according to claim 1, characterized in that: An adjustment ring is provided on the outside of the central tube (2) on the right side of the first spring seat (11), and adjustment bolts (3) are threadedly inserted in an annular array on the adjustment ring.

8. The downhole oil pipe repeatable automatic sealing valve according to claim 2, characterized in that: The left side of the cylinder (7) is connected with a lower joint (8) through a thread.

9. The downhole oil pipe repeatable automatic sealing valve according to claim 8, characterized in that: The right side of the cylinder (7) is plugged with an upper joint (1) through a thread, and the interior of the upper joint (1) is fixedly plugged with the right side of the central tube (2).

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