Underground metal control valve and using method thereof

Abstract

The invention discloses an underground metal control valve and a using method thereof, and the underground metal control valve comprises a control part which is used for being connected with a ground control device; the upper joint is arranged at the bottom of the control part; the valve body assembly is arranged at the bottom of the upper joint; the lower joint is arranged at the bottom of the valve body assembly; the control part can enable the valve body assembly to be opened and closed under remote control of a ground control device, and the control part, the upper connector, the valve body assembly and the lower connector are respectively made of metal materials. The underground metal control valve can be used under the high-temperature condition, opening and closing can be remotely controlled, and therefore the application range and adaptability of the underground metal control valve are effectively improved.

Description

Technical Field

[0001] This invention belongs to the field of downhole control valve technology, specifically relating to a downhole metal control valve and its usage method. Background Technology

[0002] Currently, marine oil and gas resources are not only abundant, but modern science and technology have also given us the enormous capacity to develop them. The marine oil and gas industry has developed into a leading emerging industry with high output value in the marine economy.

[0003] Due to the convenience, economy, and applicability of non-metallic sealing components, conventional downhole valves typically use sealing components made of non-metallic materials. The non-metallic materials used may be one or more of the following: nitrile rubber, hydrogenated nitrile rubber, fluororubber, perfluororubber, polytetrafluoroethylene, and reinforced polytetrafluoroethylene.

[0004] However, non-metallic seals are limited by the applicable temperature range of non-metallic materials, and generally cannot reach excessively high temperature limits. This is especially true in heavy oil thermal recovery processes, where the highest injection and production temperatures are quite high, even reaching 350°C. Therefore, control valves that can effectively seal and control at extremely high temperatures are required in heavy oil thermal recovery processes. Furthermore, downhole control valves in related technologies cannot be remotely controlled from the surface or wellhead, limiting their application range and adaptability, and requiring improvement. Summary of the Invention

[0005] In order to solve all or some of the above problems, the purpose of this invention is to provide a downhole metal control valve and its usage method, which can meet the requirements of high temperature conditions and can be remotely controlled to open and close, thereby effectively improving the applicability and adaptability of downhole control valves.

[0006] In a first aspect, the present invention provides a downhole metal control valve, comprising: The control unit is used to connect to the ground control device; The upper connector is located at the bottom of the control unit; The valve body assembly is located at the bottom of the upper connector; The lower connector is located at the bottom of the valve body assembly; The control unit is capable of opening and closing the valve assembly under the remote control of the ground control device, and the control unit, the upper connector, the valve assembly and the lower connector are all made of metal materials.

[0007] Optionally, the valve body assembly includes: The valve body cylinder is located at the bottom of the upper connector; A flow channel hole is provided at the lower end of the valve body cylinder; A valve seat is located at the bottom of the valve body cylinder; The valve stem is vertically and slidably connected inside the valve body cylinder; A sealing head is located at the bottom of the valve stem; A spring assembly is disposed inside the valve body cylinder; The control unit is used to move the valve stem downward and separate the sealing head from the valve seat, while the spring assembly is used to move the valve stem upward and seal the sealing head against the valve seat.

[0008] Optionally, the spring assembly includes: An upper support is provided at the top of the valve stem; The lower support is mounted on the valve body cylinder; A compression spring is sleeved on the valve stem, with its top connected to the upper support and its bottom connected to the lower support.

[0009] Optionally, the control unit includes: A control column is located at the top of the upper connector; A support groove is provided at the bottom of the control column; A connector hole is provided at the top of the control column and communicates with the support groove. The connector hole is used to connect to the transmission pipeline of the ground control device. The control rod is vertically slidably connected in the support groove. The control rod passes through the upper connector and is slidably connected to the upper connector. The bottom of the control rod is connected to the valve stem.

[0010] Optionally, the control unit further includes: An elastic component is disposed within the support groove and is used to move the control lever upward.

[0011] Optionally, the elastic component includes: A support head is located at the top of the control lever; An upper welding ring is sleeved on the control rod and welded to the support head for fixation; The lower welding ring is sleeved on the control rod and welded to the upper connector for fixation; A corrugated pipe is fitted onto the control rod, with its top connected to the upper welding ring and its bottom connected to the lower welding ring.

[0012] Optionally, the control rod is provided with a stepped surface, and the top of the upper connector is provided with a limiting surface, and the limiting surface can abut against the stepped surface for limiting.

[0013] Optionally, the control rod is threadedly connected to the valve stem.

[0014] Secondly, the present invention provides a method for using a downhole metal control valve, comprising the following steps: S1, connecting at least one downhole metal control valve to a connector assembly having at least three connection ports, wherein the connection ports of the connector assembly are interconnected. S2, connect the pressure transmission line of the surface control device to the downhole metal control valve respectively; S3, connect the connector assembly to the tubing or drill pipe and simultaneously run it into the casing. Connect at least one packer (300) to the tubing or drill pipe between at least one connector assembly (200). After the packer (300) is set, divide the tubing and casing annulus into multiple sections. Each section is equipped with at least one connector assembly (200) and a downhole metal control valve (100). Two ports of the connector assembly (200) are connected to the tubing or drill pipe. At least one other port of the connector assembly (200) is connected to the tubing and casing annulus section through the downhole metal control valve (100). S4 controls the opening or closing of the downhole metal control valve through the ground control device, thereby controlling the connection between the partition section where the connector assembly (200) and the downhole metal control valve (100) are located and the tubing or drill pipe.

[0015] Optionally, in S4, when the pressure inside the valve body assembly is lower than the first preset value, the downhole metal control valve is closed; when the pressure in the downhole metal control valve is increased to above the second preset value through the surface control device, the downhole metal control valve is opened.

[0016] As can be seen from the above technical solution, the downhole metal control valve and its usage method provided by the present invention have the following advantages: This downhole metal control valve is made entirely of metal, with metal seals between its components, ensuring both sealing performance and suitability for high-temperature applications. Furthermore, it allows for remote control of opening and closing, effectively expanding its applicability and adaptability.

[0017] Other features and advantages of the present invention will be set forth in the following description. Attached Figure Description

[0018] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the technical solutions of the present invention, and do not constitute a limitation on the technical solutions of the present invention.

[0019] Figure 1 This is a cross-sectional view of the downhole metal control valve in Embodiment 1 of the present invention; Figure 2 This is a cross-sectional view of the valve body assembly in Embodiment 1 of the present invention; Figure 3 This is a cross-sectional view of the control unit and the upper connector in Embodiment 1 of the present invention; Figure 4 for Figure 3 Enlarged view of region A in the middle; Figure 5 This is a schematic diagram showing the usage status of the downhole metal control valve in Embodiment 2 of the present invention; Figure 6 This is a cross-sectional view of the downhole metal control valve and sealing assembly in Embodiment 2 of the present invention.

[0020] Explanation of reference numerals in the attached figures: 1. Control unit; 11. Control column; 12. Support groove; 13. Connector hole; 14. Control rod; 15. Elastic assembly; 151. Support head; 152. Upper welded ring; 153. Lower welded ring; 154. Bellows; 2. Upper connector; 3. Valve body assembly; 31. Valve body cylinder; 32. Flow channel hole; 33. Valve seat; 34. Valve stem; 35. Sealing head; 36. Spring assembly; 361. Upper support; 362. Lower support; 363. Compression spring; 4. Lower connector; 5. Stepped surface; 6. Limiting surface; 100. Downhole metal control valve; 200. Connector assembly; 300. Packer. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present invention can be arbitrarily combined with each other.

[0022] Example 1 like Figure 1 , Figure 2 , Figure 3 , Figure 4 The illustration shows Embodiment 1 of the present invention, which discloses a downhole metal control valve, comprising a control unit 1, an upper connector 2, a valve body assembly 3, and a lower connector 4 connected sequentially from top to bottom. The control unit 1 is used to connect to a surface control device, and the lower connector 4 is used to connect to a sealing assembly. The control unit 1 can open and close the valve body assembly 3 under the remote control of the surface control device, and the control unit 1, upper connector 2, valve body assembly 3, and lower connector 4 are all made of metal materials.

[0023] The downhole metal control valve in this embodiment is made entirely of metal, and the corresponding components are sealed with metal seals, which ensures both sealing performance and suitability for high-temperature applications. Furthermore, this downhole metal control valve can be remotely controlled to open and close, effectively improving its applicability and adaptability.

[0024] In this embodiment, the components of the downhole metal sealing valve are made of metal materials such as martensitic stainless steel, hard alloy, alloy steel or two-dimensional stainless steel. Of course, other metal materials may also be used in other embodiments, which will not be listed in detail here.

[0025] In one embodiment, such as Figure 2 As shown, the valve body assembly 3 includes a vertically arranged valve body cylinder 31. The lower end of the valve body cylinder 31 is provided with multiple flow channel holes 32, and the flow channel holes 32 connect the interior of the valve body cylinder 31 and the well shaft annulus. At the same time, a valve seat 33 is integrally formed at the bottom of the valve body cylinder 31.

[0026] In one embodiment, such as Figure 2 As shown, a valve stem 34 is vertically slidably connected inside the valve body cylinder 31, and a sealing head 35 is threadedly connected to the bottom of the valve stem 34. A spring assembly 36 is provided inside the valve body cylinder 31. The control unit 1 is used to move the valve stem 34 downward and separate the sealing head 35 from the valve seat 33. The spring assembly 36 is used to move the valve stem 34 upward and make the sealing head 35 abut against the valve seat 33 for sealing.

[0027] In this embodiment, the top of the sealing head 35 is a spherical structure, the valve seat 33 has an arc-shaped sealing surface, and the top of the sealing head 35 can closely abut against the sealing surface on the valve seat 33 to ensure the sealing effect.

[0028] In one embodiment, such as Figure 2 As shown, the spring assembly 36 includes an upper support 361, a lower support 362, and a compression spring 363. The upper support 361 is integrally formed and connected to the top of the valve stem 34, and the lower support 362 is fixedly connected to the inner wall of the valve body cylinder 31. The compression spring 363 is sleeved on the valve stem 34, and the top of the compression spring 363 is fixedly connected to the upper support 361, and the bottom of the compression spring 363 is fixedly connected to the lower support 362.

[0029] In this embodiment, when the downhole metal control valve is in the closed state, the compression spring 363 remains compressed to maintain the sealing contact stress required for sealing between the sealing head 35 and the valve seat 33, thereby ensuring the sealing effect.

[0030] In one embodiment, such as Figure 1 , Figure 3 As shown, the control unit 1 includes a control column 11 disposed on the top of the upper connector 2. The bottom of the control column 11 is provided with a support groove 12 and the top is provided with a connector hole 13. The connector hole 13 communicates with the support groove 12 and is used to connect with the transmission line of the ground control device.

[0031] In one embodiment, such as Figure 3As shown, a control rod 14 is vertically slidably connected within the support groove 12. The control rod 14 passes through and is slidably connected to the upper connector 2. Simultaneously, the bottom of the control rod 14 is connected to the valve stem 34, enabling the control rod 14 to push the valve stem 34 downwards. The control unit 1 also includes a spring assembly 15 disposed within the support groove 12, which can push the control rod 14 upwards, allowing the downhole metal-sealed valve to close smoothly.

[0032] In one embodiment, such as Figure 3 As shown, the elastic component 15 includes a support head 151, an upper welding ring 152, a lower welding ring 153, and a bellows 154. The support head 151 is integrally formed and connected to the top of the control rod 14. The upper welding ring 152 is sleeved on the control rod 14 and welded to the support head 151. The lower welding ring 153 is sleeved on the control rod 14 and welded to the upper connector 2. The bellows 154 is sleeved on the control rod 14, with its top fixedly connected to the upper welding ring 152 and its bottom fixedly connected to the lower welding ring 153. This design can withstand a certain pressure from inside and / or outside the bellows 154 while maintaining pressure isolation between the inner and outer cavities.

[0033] In one embodiment, such as Figure 3 , Figure 4 As shown, the control rod 14 is provided with a stepped surface 5, and the top of the upper connector 2 is provided with a limiting surface 6. When the control rod 14 moves vertically downward to the point where the downhole metal control valve is opened, the limiting surface 6 can abut against the stepped surface 5 to limit the maximum displacement stroke of the control rod 14.

[0034] In one embodiment, such as Figure 1 , Figure 2 , Figure 3 As shown, the control rod 14 is threadedly connected to the valve stem 34, the valve stem 34 is threadedly connected to the sealing head 35, and the control column 11, the upper connector 2, the valve body cylinder 31 and the lower connector 4 are respectively threadedly connected to ensure the sealing effect between adjacent components.

[0035] The opening and closing principle of the downhole metal control valve in this embodiment is as follows: Pressurization is applied into the support groove 12 by an external control device. Under pressure, the control rod 14 drives the valve stem 34 and the sealing head 35 to move downward until the step surface 5 and the limiting surface 6 come into contact. At this time, the sealing head 35 separates from the valve seat 33. The downhole metal control valve opens, and the compression spring 363 and the bellows 154 are in a compressed state.

[0036] When the external control device is depressurized, the control rod 14 and valve stem 34 move upward synchronously under the elastic force of the bellows 154 and compression spring 363. When the sealing head 35 is tightly abutted against the valve seat 33, the downhole metal control valve is closed. At this time, the compression spring 363 and bellows 154 are still in a compressed state to ensure the sealing effect.

[0037] Example 2 like Figure 5 , Figure 6 The following is an embodiment 2 of the present invention, which discloses a method for using a downhole metal control valve, including the following steps: S1, connect at least one downhole metal control valve 100 to a connector assembly 200 having at least three connection ports, wherein the connection ports of the connector assembly 200 are interconnected. S2, connect the pressure transmission line of the surface control device to all the downhole metal control valves 100 in S1 respectively; S3, connect the connector assembly 200 to the tubing or drill pipe and simultaneously run it into the casing. Connect at least one packer 300 to the tubing or drill pipe between at least one connector assembly 200. After the packer 300 is set, divide the tubing and casing annulus into multiple segments. Each segment is equipped with at least one connector assembly 200 and a downhole metal control valve 100. Two ports of the connector assembly 200 are connected to the tubing or drill pipe, and at least one other port of the connector assembly 200 is connected to the tubing and casing annulus segment through the downhole metal control valve 100. S4 controls the opening or closing of the downhole metal control valve 100 via the ground control device, thereby controlling the connection between the connector assembly 200 and the partition section where the downhole metal control valve 100 is located and the tubing or drill pipe.

[0038] In S4, when the pressure inside the valve body assembly 3 is lower than the first preset value, the downhole metal control valve 100 is closed; when the pressure in the downhole metal control valve 100 is increased to above the second preset value by the surface control device, the downhole metal control valve 100 is opened.

[0039] To illustrate this embodiment more clearly, taking an example where the sealing assembly has three connection ports and two packers 300, with two of the connection ports respectively equipped with downhole metal control valves 100, the specific usage method is as follows: Two downhole metal control valves 100 are respectively installed on two connection ports of the sealing assembly, and the two downhole metal control valves 100 and two packers 300 are arranged at intervals. At the same time, the two pressure transmission lines of the external control device are respectively connected to the corresponding connector holes 13. Then the sealing assembly is installed on the upper end of the tubing or drill pipe. Subsequently, the sealing assembly is lowered into the well using tubing or drill pipe, and the two packers 300 are respectively set on the inner wall of the wellbore.

[0040] Since the downhole metal control valve 100 is a normally closed valve, the sealing head 35 and the valve seat 33 remain sealed in the initial state, keeping the downhole metal control valve 100 in the closed state. With pressure application from the surface control device, the downhole metal control valve 100 transitions from the closed state to the open state. When the sealing head 35 separates from the valve seat 33, the downhole metal control valve 100 is in the open state. Furthermore, the two downhole metal control valves 100 on this sealing assembly can be opened and closed independently, making it suitable for layered mining operations and functions such as well shut-off, thereby expanding the applicability of the downhole metal control valve 100.

[0041] As can be seen from the above, the downhole metal control valve has no non-metallic parts. The static and dynamic seals inside the valve are both metal-to-metal seals. Metal bellows are used to replace the dynamic sealing elements. A mechanical limit structure is provided to prevent damage to the bellows and compression springs caused by excessive control pressure.

[0042] Meanwhile, the downhole metal control valve can be opened and closed remotely using a hydraulic control method. Furthermore, the downhole metal control valve, together with the connector assembly, can be used to remotely and independently control the opening and closing of each section in the injection and production tubing of heavy oil thermal recovery wells.

[0043] In addition, this downhole metal control valve can be used in both high-temperature heavy oil thermal recovery wells and conventional cold recovery wells. It not only solves the problem that conventional downhole control valves cannot be used in extremely high-temperature environments due to the limitation of their applicable temperature range, but also solves the control problems of independent injection control, production channel connection and closure in different layers, which significantly improves the technical level of heavy oil thermal recovery technology.

[0044] It should be noted that, unless otherwise stated, the technical or scientific terms used in this invention should have the ordinary meaning as understood by one of ordinary skill in the art.

[0045] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly defined.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A downhole metal control valve, characterized in that, include: Control unit (1), used for connection with ground control device; The upper connector (2) is located at the bottom of the control unit (1); The valve body assembly (3) is located at the bottom of the upper connector (2); The lower connector (4) is located at the bottom of the valve body assembly (3); The control unit (1) is able to open and close the valve body assembly (3) under the remote control of the ground control device, and the control unit (1), the upper connector (2), the valve body assembly (3) and the lower connector (4) are all made of metal materials.

2. The downhole metal control valve according to claim 1, characterized in that, The valve body assembly (3) includes: Valve body cylinder (31) is located at the bottom of the upper connector (2); A flow channel hole (32) is provided at the lower end of the valve body cylinder (31); A valve seat (33) is disposed at the bottom of the valve body cylinder (31); The valve stem (34) is vertically slidably connected inside the valve body cylinder (31); A sealing head (35) is disposed at the bottom of the valve stem (34); A spring assembly (36) is disposed inside the valve body cylinder (31); The control unit (1) is used to move the valve stem (34) downward and separate the sealing head (35) from the valve seat (33), and the spring assembly (36) is used to move the valve stem (34) upward and seal the sealing head (35) against the valve seat (33).

3. The downhole metal control valve according to claim 2, characterized in that, The spring assembly (36) includes: An upper support (361) is provided on the top of the valve stem (34); The lower support (362) is disposed on the valve body cylinder (31); A compression spring (363) is sleeved on the valve stem (34), and the top of the compression spring (363) is connected to the upper support (361) and the bottom is connected to the lower support (362).

4. The downhole metal control valve according to claim 2, characterized in that, The control unit (1) includes: A control column (11) is located at the top of the upper connector (2); A support groove (12) is provided at the bottom of the control column (11); A connector hole (13) is provided on the top of the control column (11) and communicates with the support groove (12). The connector hole (13) is used to connect with the transmission line of the ground control device. The control rod (14) is vertically slidably connected in the support groove (12). The control rod (14) passes through the upper connector (2) and is slidably connected to the upper connector (2). The bottom of the control rod (14) is connected to the valve stem (34).

5. The downhole metal control valve according to claim 4, characterized in that, The control unit (1) further includes: The elastic component (15) is disposed in the support groove (12) and is used to move the control rod (14) upward.

6. The downhole metal control valve according to claim 5, characterized in that, The elastic component (15) includes: A support head (151) is disposed on the top of the control rod (14); The upper welding ring (152) is sleeved on the control rod (14) and welded to the support head (151); The lower welding ring (153) is sleeved on the control rod (14) and welded to the upper connector (2); A bellows (154) is fitted onto the control rod (14). The top of the bellows (154) is connected to the upper welding ring (152), and the bottom is connected to the lower welding ring (153).

7. The downhole metal control valve according to claim 4, characterized in that, The control rod (14) is provided with a stepped surface (5), and the top of the upper connector (2) is provided with a limiting surface (6), and the limiting surface (6) can abut against the stepped surface (5) for limiting.

8. The downhole metal control valve according to claim 4, characterized in that, The control lever (14) is threadedly connected to the valve stem (34).

9. A method of using the downhole metal control valve according to any one of claims 1-8, characterized in that, Includes the following steps: S1, connecting at least one downhole metal control valve (100) to a connector assembly (200) having at least three connection ports, wherein the connection ports of the connector assembly (200) are interconnected. S2, connect the pressure transmission line of the ground control device to the downhole metal control valve (100) respectively; S3, connect the connector assembly (200) to the tubing or drill pipe and simultaneously run it into the casing. Connect at least one packer (300) to the tubing or drill pipe between at least one connector assembly (200). After the packer (300) is set, divide the tubing and casing annulus into multiple sections. Each section is equipped with at least one connector assembly (200) and a downhole metal control valve (100). Two ports of the connector assembly (200) are connected to the tubing or drill pipe. At least one other port of the connector assembly (200) is connected to the tubing and casing annulus section through the downhole metal control valve (100). S4 controls the opening or closing of the downhole metal control valve (100) by outputting pressure through the ground control device, thereby controlling the connection between the joint assembly (200) and the partition section where the downhole metal control valve (100) is located and the tubing or drill pipe.

10. The method of use according to claim 9, characterized in that, In S4, when the pressure inside the valve body assembly (3) is lower than the first preset value, the downhole metal control valve (100) is closed; when the pressure is increased to the downhole metal control valve (100) by the ground control device to a value above the second preset value, the downhole metal control valve (100) is opened.

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