An injection-production integrated device and injection-production method

Abstract

This invention discloses an integrated injection and production device and method, improving upon the low efficiency and complex operation of existing oil well injection and production operations. The device includes a concentrically arranged outer tubing assembly and an inner tubing assembly, which are vertically slidingly fitted together. The outer tubing assembly includes an upper insulated tubing, a jet pump working cylinder, and a lower insulated tubing. The inner tubing assembly includes an injection and production pipe, a jet pump inner cylinder, an upper plunger, a steam injection sub, a spring valve, and a lower plunger. When heated, the injection and production pipe elongates, allowing the steam injection sub to extend from the jet pump working cylinder. The spring valve is configured such that its internal flow channel can open during hot injection operations, allowing steam to flow downwards, and during oil production operations, it can open to allow formation fluids to flow upwards. This invention can meet injection and production needs with a single tubing string, improving production efficiency, reducing heat loss, and enhancing operational convenience.

Description

Technical Field

[0001] This invention belongs to the field of offshore heavy oil thermal recovery technology, specifically relating to an integrated injection and production device and injection and production method. Background Technology

[0002] Currently, the development of heavy oil thermal recovery is limited by the temperature resistance of lifting tools. It is usually completed by two sets of tubing. One set of tubing is the injection tubing, which is specifically used to inject high-temperature hot fluid into the well to reduce the viscosity of crude oil. After the injection is completed, another set of production tubing is run to extract the downhole fluid after the injection and viscosity reduction, thus completing the entire extraction process.

[0003] However, the aforementioned heavy oil thermal recovery methods not only affect oil production efficiency, but also cause well workover fluid to contaminate the reservoir and reduce the thermal injection effect during the injection-production conversion process, which needs to be improved. Summary of the Invention

[0004] In order to solve all or some of the above problems, the purpose of this invention is to provide an integrated injection and production device and method, which can meet the injection and production needs with a single tubing string, thereby improving production efficiency, reducing heat loss, and improving operational convenience.

[0005] In a first aspect, the present invention provides an integrated injection and production device, comprising an outer tubing assembly and an inner tubing assembly arranged concentrically, wherein the inner tubing assembly and the outer tubing assembly are vertically slidingly connected, the outer tubing assembly comprising an upper heat-insulating oil pipe, a jet pump working cylinder and a lower heat-insulating oil pipe connected sequentially from top to bottom, and the inner tubing assembly comprising an injection and production pipe, a jet pump inner pump cylinder, an upper plunger, a steam injection short section, a spring valve and a lower plunger connected sequentially from top to bottom;

[0006] After being heated and elongated, the injection and production pipe allows the steam injection stub to extend from the jet pump working cylinder, enabling steam to enter the formation through the annulus between the steam injection stub and the outer tubing assembly. The spring valve is configured such that its internal flow channel can be opened during hot injection operations to allow steam to flow downwards through the spring valve, and its internal flow channel can be opened during oil production operations to allow formation fluids to flow upwards through the spring valve.

[0007] Optionally, the spring valve includes:

[0008] The valve body is cylindrical and connected to the bottom of the steam injection sub.

[0009] The valve seat is cylindrical and is concentrically movably disposed within the valve body, and an annular steam injection channel is formed between the outer wall of the valve seat and the inner wall of the valve body;

[0010] The valve core ball has a diameter smaller than the inner diameter of the valve seat and is movably disposed within the valve seat;

[0011] A disc spring is disposed within the valve body and is used to push the valve seat upward;

[0012] The valve seat has a first sealing surface at the lower end of its inner wall, and the valve core ball can abut against the first sealing surface to seal. The valve seat has a second sealing surface at the upper end of its inner wall, and the valve seat can abut against the second sealing surface to seal under the elastic force of the disc spring.

[0013] Optionally, the upper end of the valve seat is provided with a third sealing surface, and the third sealing surface can abut against the second sealing surface to seal.

[0014] Optionally, the bottom of the valve seat is provided with an annular spring seat, the lower end of the inner wall of the valve body is provided with a support ring, one end of the disc spring is located inside the spring seat and is fixedly connected to the spring seat, and the other end is fixedly connected to the support ring.

[0015] Optionally, the disc spring has a spring stiffness of 600-900 N / mm and an opening pressure of 4-10 MPa.

[0016] Optionally, a plurality of limiting blocks are provided at the upper end of the inner wall of the valve seat. The plurality of limiting blocks are arranged at equal intervals along the axial direction of the valve seat, and a formation fluid flow channel is formed between two adjacent limiting blocks. Each limiting block is provided with a limiting inclined surface, and the plurality of limiting inclined surfaces are used to jointly block the upward movement of the valve core ball.

[0017] Optionally, the steam injection section includes a steam injection cylinder with multiple steam injection holes. The multiple steam injection holes are arranged at equal intervals along the circumference of the steam injection cylinder, and after the injection pipe is heated and elongated, the multiple steam injection holes are exposed from the working cylinder of the jet pump.

[0018] Secondly, the present invention provides an injection-production method using an integrated injection-production device, comprising the following steps:

[0019] S1, Assemble the outer tube column assembly and the inner tube column assembly separately and insert them into the production sleeve, with the inner tube column assembly concentrically located inside the outer tube column assembly;

[0020] S2, Perform pressure testing on the outer tubing assembly and the inner tubing assembly;

[0021] S3, lift the inner tube column assembly to allow the steam injection short section to enter the predetermined position inside the jet pump working cylinder;

[0022] S4, steam is injected into the inner tube assembly through the heating equipment, and high-purity nitrogen is injected into the annulus between the production casing and the outer tube assembly at the same time as the heating operation.

[0023] S5, after the heating operation is completed, the well is shut-off operation is carried out, and after the well shut-off operation is completed, the self-flowing production mode is switched;

[0024] S6, after the self-flowing production mode ends, the fixed valve and jet pump production core are put into the inner tubing assembly, so that the jet pump production core enters the predetermined position inside the jet pump barrel, and then the power fluid is injected through the surface plunger pump to switch to the oil well production mode.

[0025] Optionally, in S4, during the initial stage of the heat injection operation, the spring valve opens its internal flow channel under the pressure of steam to allow steam to be injected into the well. During the later stage of the heat injection operation, as the temperature rises, the injection and production pipe gradually extends to allow the steam injection sub-section to extend from the working cylinder of the jet pump. At this time, the spring valve closes its internal flow channel to allow steam to be injected into the well through the steam injection sub-section.

[0026] Optionally, in S6, during the initial stage of the well production mode, the spring valve opens its internal flow channel, and the formation fluid enters the injection-production pipe and reaches the surface simultaneously through the steam injection sub and the spring valve. In the later stage of the well production mode, as the temperature decreases, the injection-production pipe gradually contracts so that the steam injection sub enters the working cylinder of the jet pump. At this time, the formation fluid enters the injection-production pipe and reaches the surface only through the spring valve.

[0027] As can be seen from the above technical solutions, the integrated injection and extraction device and method provided by the present invention have the following advantages:

[0028] This device allows injection and production needs to be met with a single tubing string, simplifying the process, improving production efficiency, reducing heat loss, and enhancing operational convenience.

[0029] Other features and advantages of the present invention will be set forth in the following description. Attached Figure Description

[0030] 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.

[0031] Figure 1 This is a schematic diagram of the usage state of the integrated injection and extraction device in an embodiment of the present invention;

[0032] Figure 2 This is a cross-sectional view of the outer tubular assembly in an embodiment of the present invention;

[0033] Figure 3 This is a cross-sectional view of the inner tubular column assembly in an embodiment of the present invention;

[0034] Figure 4 This is a cross-sectional view of the spring valve in an embodiment of the present invention;

[0035] Figure 5This is a cross-sectional view of the steam injection short section in an embodiment of the present invention;

[0036] Figure 6 This is a cross-sectional view of the spring valve in an embodiment of the present invention, showing the heat injection operation state;

[0037] Figure 7 This is a cross-sectional view of the spring valve in an embodiment of the present invention, showing the oil production operation status.

[0038] Explanation of reference numerals in the attached figures:

[0039] 1. Outer tubing assembly; 11. Upper insulated tubing; 12. Jet pump working cylinder; 13. Lower insulated tubing; 2. Inner tubing assembly; 21. Injection / production tubing; 22. Jet pump inner cylinder; 23. Upper plunger; 24. Steam injection sub; 241. Steam injection cylinder; 242. Steam injection port; 25. Spring valve; 251. Valve body; 252. Valve seat; 253. Valve core ball; 254. Disc spring; 255. Steam injection channel; 256. First sealing surface; 257. Second sealing surface; 258. Third sealing surface; 259. Spring seat; 260. Support ring; 261. Limiting block; 262. Limiting ramp; 263. Formation fluid channel; 26. Lower plunger. Detailed Implementation

[0040] 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.

[0041] like Figures 1-7 The figure shown is an embodiment of the present invention. This embodiment discloses an integrated injection and extraction device and injection and extraction method, including an outer tubing assembly 1 and an inner tubing assembly 2. The inner tubing assembly 2 is concentrically disposed inside the outer tubing assembly 1, and the inner tubing assembly 2 and the outer tubing assembly 1 are vertically slidingly engaged.

[0042] In one embodiment, such as Figure 1 , Figure 2 , Figure 3 As shown, the outer tubing assembly 1 includes an upper insulated oil pipe 11, a jet pump working cylinder 12, and a lower insulated oil pipe 13, which are connected in sequence from top to bottom by threads. The inner tubing assembly 2 includes an injection and production pipe 21, a jet pump inner pump cylinder 22, an upper plunger 23, a steam injection short section 24, a spring valve 25, and a lower plunger 26, which are connected in sequence from top to bottom by threads.

[0043] In one embodiment, such as Figure 1 , Figure 2 , Figure 3As shown, the inner pump cylinder 22, upper plunger 23, steam injection stub 24, spring valve 25, and lower plunger 26 of the jet pump have the same outer diameter and are sealed with the working cylinder 12 of the jet pump through a gap. This allows the inner pump cylinder 22, upper plunger 23, steam injection stub 24, spring valve 25, and lower plunger 26 of the jet pump to slide smoothly within the working cylinder 12 of the jet pump, ensuring that the inner tube assembly 2 can freely extend within the working cylinder 12 of the jet pump under different ambient temperatures, while also ensuring a reasonable leakage rate.

[0044] In one embodiment, such as Figure 1 , Figure 2 , Figure 3 As shown, the inner diameter of the upper insulated oil pipe 11 is larger than the inner diameter of the jet pump working cylinder 12, so that the inner tubing assembly 2 can be smoothly lowered into the jet pump working cylinder 12. The inner diameter of the lower insulated oil pipe 13 is larger than the inner diameter of the jet pump working cylinder 12. After the injection and production pipe 21 is heated and elongated, the steam injection stub 24 can extend out of the jet pump working cylinder 12, so that steam can enter the formation through the annulus between the steam injection stub 24 and the outer tubing assembly 1.

[0045] In one embodiment, such as Figure 1 As shown, the spring valve 25 is configured such that its internal flow channel can be opened during heat injection operations to allow steam to flow downward through the spring valve 25, and its internal flow channel can be opened during oil production operations to allow formation fluid to flow upward through the spring valve 25, thereby meeting the injection and production requirements.

[0046] In one embodiment, such as Figure 1 , Figure 4 As shown, the spring valve 25 includes a valve body 251, a valve seat 252, a valve core ball 253, and a disc spring 254. The valve body 251 is cylindrical and coaxially threaded to the bottom of the steam injection stub 24. The valve seat 252 is cylindrical and concentrically movably disposed within the valve body 251, and an annular steam injection channel 255 is formed between the outer wall of the valve seat 252 and the inner wall of the valve body 251. The diameter of the valve core ball 253 is smaller than the inner diameter of the valve seat 252, and the valve core ball 253 is movably disposed within the valve seat 252. The disc spring 254 is disposed within the valve body 251 and is used to push the valve seat 252 upward.

[0047] In one embodiment, such as Figure 1 , Figure 4 As shown, a first sealing surface 256 is provided at the lower end of the inner wall of the valve seat 252, and the valve core ball 253 can abut against the first sealing surface 256 to seal. A second sealing surface 257 is provided at the upper end of the inner wall of the valve body 251, and a third sealing surface 258 is provided at the upper end of the valve seat 252. The valve seat 252 can abut against the second sealing surface 257 to seal under the elastic force of the disc spring 254.

[0048] In one embodiment, such as Figure 1 , Figure 4 As shown, an annular spring seat 259 is integrally formed at the bottom of the valve seat 252, and a support ring 260 is integrally formed at the lower end of the inner wall of the valve body 251. One end of the disc spring 254 is located inside the spring seat 259 and is fixedly connected to the spring seat 259, and the other end is fixedly connected to the support ring 260 to ensure that the disc spring 254 can be compressed smoothly and to raise the guide slope so that the valve seat 252 can move smoothly and vertically.

[0049] In one embodiment, such as Figure 1 , Figure 4 As shown, multiple limiting blocks 261 are integrally formed at the upper end of the inner wall of the valve seat 252. The multiple limiting blocks 261 are arranged at equal intervals along the axial direction of the valve seat 252, and formation fluid flow channels 263 are formed between adjacent two limiting blocks 261. At the same time, each limiting block 261 is provided with a limiting inclined surface 262. The multiple limiting inclined surfaces 262 are used to jointly block the upward movement of the valve core ball 253, so as to prevent the valve core ball 253 from sliding out from the top of the valve seat 252 during oil production operations.

[0050] In this embodiment, the disc spring 254 is made of 718 stainless steel. The spring stiffness of the disc spring 254 is 600-900 N / mm and the opening pressure is 4-10 MPa. It can meet both the initial steam injection discharge requirements and the discharge requirements of the fixed valve of the salvage jet pump.

[0051] In one embodiment, such as Figure 1 , Figure 5 As shown, the steam injection short section 24 includes a steam injection cylinder 241, on which a plurality of steam injection holes 242 are provided. The plurality of steam injection holes 242 are arranged at equal intervals along the circumference of the steam injection cylinder 241, and after the injection and extraction pipe 21 is heated and elongated, the plurality of steam injection holes 242 are exposed from the jet pump working cylinder 12 respectively.

[0052] The integrated injection and extraction device in this embodiment can meet the injection and extraction needs in a single trip, which can improve production efficiency, reduce heat loss and operating costs, and improve operational convenience. The opening pressure of the spring valve 25 can be adjusted according to the injection and extraction conditions, ensuring both normal steam injection and reliable valve retrieval. The inner pump cylinder 22, upper plunger 23, steam injection sub-section 24, spring valve 25, and lower plunger 26 of the jet pump are designed with the same outer diameter, ensuring that the inner tube assembly 2 can freely extend without jamming within the working cylinder 12 of the jet pump after being heated.

[0053] This embodiment also discloses an injection-production method using the aforementioned integrated injection-production device. The injection-production method includes the following steps:

[0054] S1, Assemble the outer tube assembly 1 and the inner tube assembly 2 respectively and insert them into the production sleeve, with the inner tube assembly 2 concentrically located inside the outer tube assembly 1;

[0055] S2, perform pressure testing on the outer tubing assembly 1 and the inner tubing assembly 2;

[0056] S3, lift the inner tube assembly 2, so that the steam injection short section 24 enters the predetermined position inside the jet pump working cylinder 12. At this time, the jet pump inner cylinder 22, upper plunger 23, steam injection short section 24, spring valve 25 and lower plunger 26 are respectively located inside the jet pump working cylinder 12.

[0057] S4. Steam is injected into the inner tubing assembly 2 through the heating equipment. At the same time as the heating operation, high-purity nitrogen is injected into the annulus between the production casing and the outer tubing assembly 1 to reduce the temperature of the wellbore annulus where the inner tubing assembly 2 is located.

[0058] S5, after the heating operation is completed, the well is shut-off operation is carried out, and after the well shut-off operation is completed, the self-flowing production mode is switched;

[0059] S6, after the self-flowing production mode ends, the fixed valve and jet pump production pump core are put into the inner tubing assembly 2, so that the jet pump production pump core enters the predetermined position inside the inner pump barrel 22 of the jet pump, and then the power fluid is injected through the ground plunger pump to switch to the oil well production mode.

[0060] In S4, such as Figure 6 As shown, in the initial stage of the heat injection operation, the valve core ball 253 abuts and seals with the first sealing surface 256, and the spring valve 25 is pressurized. Under the pressure of steam, the valve core ball 253 and the valve seat 252 move downward and compress the disc spring 254. At the same time, the second sealing surface 257 and the third sealing surface 258 separate, that is, the internal flow channel of the spring valve 25 opens. At this time, steam moves downward through the steam injection flow channel 255 between the valve seat 252 and the valve body 251 and is injected into the well.

[0061] In the later stages of the thermal injection operation, as the temperature rises, the injection-production pipe 21 gradually elongates, allowing the steam injection sub-section 24 to extend from the jet pump working cylinder 12, meaning that multiple steam injection holes 242 protrude from the jet pump working cylinder 12. Subsequently, the valve seat 252 moves upward under the action of the disc spring 254, causing the second sealing surface 257 and the third sealing surface 258 to abut and seal, that is, the spring valve 25 closes its internal flow channel. At this time, steam is injected into the well through the steam injection sub-section 24.

[0062] In S6, such as Figure 7As shown, in the initial stage of the oil well production mode, the valve core ball 253 moves upward under the action of the formation fluid until it abuts against multiple limiting inclined surfaces 262. At this time, some formation fluid enters the injection-production pipe 21 through the steam injection sub 24 and reaches the surface, while some formation fluid enters the valve seat 252 and enters the injection-production pipe 21 through the formation fluid flow channel 263 and reaches the surface. In the later stage of the oil well production mode, as the temperature decreases, the injection-production pipe 21 gradually contracts, and the steam injection sub 24 enters the jet pump working cylinder 12. At this time, the formation fluid only enters the injection-production pipe 21 and reaches the surface through the spring valve 25.

[0063] As can be seen from the above, this injection and extraction method is simpler and more convenient to operate, and the staff can quickly switch between injection and production, truly realizing the integrated injection and extraction capability, which can not only reduce the burden on the staff, but also improve the work efficiency.

[0064] 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.

[0065] 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.

[0066] 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. An integrated injection and extraction device, characterized in that, It includes an outer tubing assembly (1) and an inner tubing assembly (2) arranged concentrically, and the inner tubing assembly (2) and the outer tubing assembly (1) are vertically slidingly connected. The outer tubing assembly (1) includes an upper heat-insulating oil pipe (11), a jet pump working cylinder (12) and a lower heat-insulating oil pipe (13) connected from top to bottom. The inner tubing assembly (2) includes an injection and production pipe (21), a jet pump inner pump cylinder (22), an upper plunger (23), a steam injection short section (24), a spring valve (25) and a lower plunger (26) connected from top to bottom. After the injection and production pipe (21) is heated and elongated, the steam injection stub (24) can extend out of the jet pump working cylinder (12) so that steam can enter the formation through the annulus between the steam injection stub (24) and the outer tubing assembly (1). The spring valve (25) is configured such that: during the heat injection operation, the internal flow channel can be opened so that steam can flow downward through the spring valve (25); during the oil production operation, the internal flow channel can be opened so that formation fluid can flow upward through the spring valve (25).

2. The injection-production integrated device according to claim 1, characterized in that, The spring valve (25) includes: The valve body (251) is cylindrical and connected to the bottom of the steam injection stub (24); The valve seat (252) is cylindrical and is concentrically and movably disposed inside the valve body (251), and an annular steam injection channel (255) is formed between the outer wall of the valve seat (252) and the inner wall of the valve body (251). The valve core ball (253) has a diameter smaller than the inner diameter of the valve seat (252) and is movably disposed within the valve seat (252); A disc spring (254) is disposed inside the valve body (251) and is used to push the valve seat (252) upward; The valve seat (252) has a first sealing surface (256) at the lower end of its inner wall, and the valve core ball (253) can abut against the first sealing surface (256) for sealing. The valve body (251) has a second sealing surface (257) at the upper end of its inner wall, and the valve seat (252) can abut against the second sealing surface (257) for sealing under the elastic force of the disc spring (254).

3. The injection-production integrated device according to claim 2, characterized in that, The upper end of the valve seat (252) is provided with a third sealing surface (258), and the third sealing surface (258) can abut and seal with the second sealing surface (257).

4. The injection-production integrated device according to claim 2, characterized in that, The bottom of the valve seat (252) is provided with an annular spring seat (259), and the lower end of the inner wall of the valve body (251) is provided with a support ring (260). One end of the disc spring (254) is located inside the spring seat (259) and is fixedly connected to the spring seat (259), and the other end is fixedly connected to the support ring (260).

5. The injection-production integrated device according to claim 2, characterized in that, The disc spring (254) has a spring stiffness of 600-900 N / mm and an opening pressure of 4-10 MPa.

6. The injection-production integrated device according to claim 2, characterized in that, Multiple limiting blocks (261) are provided at the upper end of the inner wall of the valve seat (252). The multiple limiting blocks (261) are arranged at equal intervals along the circumference of the valve seat (252), and a formation fluid flow channel (263) is formed between two adjacent limiting blocks (261). Each limiting block (261) is provided with a limiting inclined surface (262). The multiple limiting inclined surfaces (262) are used to jointly block the upward movement of the valve core ball (253).

7. The injection-production integrated device according to claim 1, characterized in that, The steam injection short section (24) includes a steam injection cylinder (241), on which a plurality of steam injection holes (242) are provided. The plurality of steam injection holes (242) are arranged at equal intervals along the circumference of the steam injection cylinder (241), and after the injection pipe (21) is heated and elongated, the plurality of steam injection holes (242) are exposed from the jet pump working cylinder (12).

8. A method for injection and collection, using the integrated injection and collection device according to any one of claims 1-7, characterized in that, Includes the following steps: S1, the outer tube assembly (1) and the inner tube assembly (2) are assembled and lowered into the production sleeve respectively, and the inner tube assembly (2) is concentrically located inside the outer tube assembly (1); S2, pressure test the outer tubing assembly (1) and the inner tubing assembly (2); S3, lift the inner tube column assembly (2) to allow the steam injection short section (24) to enter the predetermined position inside the jet pump working cylinder (12); S4, steam is injected into the inner tube assembly (2) through the heating equipment, and high-purity nitrogen is injected into the annulus between the production casing and the outer tube assembly (1) at the same time as the heating operation. S5, after the heating operation is completed, the well is shut-off operation is carried out, and after the well shut-off operation is completed, the self-flowing production mode is switched; S6. After the self-flowing production mode ends, the fixed valve and jet pump production core are put into the inner tubing assembly (2), so that the jet pump production core enters the predetermined position inside the inner pump barrel (22) of the jet pump, and then the power fluid is injected through the ground plunger pump to switch to the oil well production mode.

9. The injection and extraction method according to claim 8, characterized in that, In S4, during the initial stage of the heat injection operation, the spring valve (25) opens its internal flow channel under the pressure of steam to allow steam to be injected into the well. During the later stage of the heat injection operation, as the temperature rises, the injection and production pipe (21) gradually extends so that the steam injection sub (24) extends out from the working cylinder (12) of the jet pump. At this time, the spring valve (25) closes its internal flow channel so that steam is injected into the well through the steam injection sub (24).

10. The injection and extraction method according to claim 8, characterized in that, In S6, during the initial stage of the well production mode, the spring valve (25) opens its internal flow channel, and the formation fluid enters the injection-production pipe (21) and reaches the surface simultaneously through the steam injection sub (24) and the spring valve (25). In the later stage of the well production mode, as the temperature decreases, the injection-production pipe (21) gradually contracts so that the steam injection sub (24) enters the jet pump working cylinder (12). At this time, the formation fluid enters the injection-production pipe (21) and reaches the surface only through the spring valve (25).

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