Cable control type underground injection allocation device for polymer injection and profile control

Abstract

The cable control type underground injection allocator comprises an upper connector, an upper connecting pipe, an injection allocator body, a lower connecting pipe and a lower connector which are sequentially connected from top to bottom, an overflowing channel is formed in the center of the interior of the cable control type underground injection allocator, and cable interfaces are formed in the two sides of the injection allocator body. An upper threading pipe and a lower threading pipe are arranged between the upper connector and the upper connecting pipe and between the lower connector and the lower connecting pipe respectively, and the steel pipe cable penetrates through the upper threading pipe and the lower threading pipe and is connected with the cable connector through the cable connector. Meanwhile, a channel shared by polymer injection and profile control is arranged in the injection allocator body, and the polymer injection function and the profile control function can be intelligently switched, so that the structural composition of the whole device is effectively simplified, the product cost is reduced, and the product reliability is improved.

Description

Technical Field

[0001] The invention relates to the field of oil field downhole equipment, in particular to a cable-controlled downhole injector for polymer injection and profile control. Background Art

[0002] Polymer flooding is a method of injecting polymer solutions into oil reservoirs to increase the viscosity of water, reduce the mobility ratio, and thus increase the swept volume, allowing more crude oil to be displaced. It is a key development technology for further improving crude oil recovery rates in major oil fields across the country after water flooding.

[0003] Polymer flooding is costly. Due to variations in permeability within reservoirs, the injected polymer preferentially enters the high-permeability zone, preventing the effective displacement of crude oil from the low-permeability zone. To improve the economic benefits of polymer flooding, polymer flooding wells require regular profile control. Profile control involves injecting granular plugging agents to reduce the permeability of high-permeability zones, forcing the polymer to migrate to low-permeability zones. This process significantly extends the effective flooding cycle of polymers and increases the oil change rate per ton of polymer, making it an essential supporting technology for polymer flooding.

[0004] Typically, during construction, a profile control pipe is first run to perform the profile control operation. Once completed, the profile control string is removed, and then a separate polymer injection string is run. This process is time-consuming, costly, and requires complex equipment. Furthermore, because polymer flow control requires a large throttling pressure differential and minimal viscosity loss, the stroke of the polymer flow control mechanism is generally long, increasing the overall length of the instrument and making on-site construction inconvenient. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a cable-controlled downhole injector for polymer injection and profile control, which can realize the integration of polymer injection and profile control, and has a compact overall structure and high space utilization.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a cable-controlled downhole injector for polymer injection and profile control, comprising an upper joint, an upper connecting pipe, an injector body, a lower connecting pipe, and a lower joint connected in sequence from top to bottom, with a flow passage formed in the center thereof; cable interfaces are provided on both sides of the injector body; an upper threading pipe and a lower threading pipe are provided between the upper joint and the upper connecting pipe and between the lower joint and the lower connecting pipe, respectively; a steel pipe cable passes through the upper threading pipe and the lower threading pipe, respectively, and is connected to the cable interface via a cable joint;

[0007] The dispenser body includes a central mounting body eccentrically arranged on one side of the flow channel, a motor assembly is arranged on the left side of the central mounting body, a flow test assembly is arranged on the right side, a transmission shaft, a transmission screw, a valve core and a valve sleeve are arranged inside, and a liquid outlet is also provided on the central mounting body, and the liquid outlet is provided at the left end of the valve sleeve, one end of the transmission shaft is connected to the motor assembly, and the other end is connected to one end of the transmission screw, and the other end of the transmission screw is connected to the valve core so that the valve core can reciprocate along the direction of the valve sleeve, a number of annular pressure reducing grooves are provided in the valve sleeve, and the right end of the valve sleeve is connected to the flow test assembly.

[0008] The cable interfaces are installed on both sides of the central installation body and arranged oppositely.

[0009] The flow channel angle of the flow testing assembly is less than 30°.

[0010] A first circuit assembly is also provided inside the central mounting body, and a second circuit assembly is provided on the left side. The first circuit assembly is electrically connected to the second circuit assembly, the second circuit assembly is connected to the motor assembly through a wire connector, and the first circuit assembly is electrically connected to the flow test assembly.

[0011] A pressure-sensitive component is further provided inside the central installation body, and the pressure-sensitive component is electrically connected to the first circuit component.

[0012] A dynamic sealing assembly is provided between the motor assembly and the transmission shaft.

[0013] Beneficial effects of the present invention:

[0014] 1. The steel tube cable installation structure of the present invention fully utilizes the length of the device body itself, eliminating the need to separately set up cable installation interfaces at the upper and lower ends of the device and the reserved installation length of cable connectors, thereby effectively shortening the overall length of the device;

[0015] 2. The injection and profile control channels are shared. The motor assembly drives the position of the regulating valve core to achieve intelligent switching between the injection and profile control functions, thereby simplifying the structure of the entire device, reducing product costs and improving product reliability.

[0016] 3. With modular design, all functional modules are integrated into the dispenser body and eccentrically arranged on one side of the flow channel to ensure that there is enough space in the flow channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below in conjunction with the accompanying drawings:

[0018] Figure 1 It is a structural schematic diagram of the present invention;

[0019] Figure 2 It is a side view of the dispenser body of the present invention;

[0020] Figure 3 for Figure 2 A-direction sectional view;

[0021] Figure 4 It is a schematic diagram of the injection polymerization process of the present invention;

[0022] Figure 5 It is a schematic diagram of the profile control work of the present invention;

[0023] In the figure: 1. Upper joint; 2. Upper connecting pipe; 3. Dispenser body; 4. Lower connecting pipe; 5. Lower joint; 6. Cable interface; 7. Upper threading tube; 8. Lower threading tube; 9. Steel pipe cable; 10. Cable joint; 301. Center mounting body; 302. Motor assembly; 303. Flow test assembly; 304. Drive shaft; 305. Drive screw; 306. Valve core; 307. Valve sleeve; 308. Liquid outlet; 309. Annular pressure reducing groove; 3010. First circuit assembly; 3011. Second circuit assembly; 3012. Pressure sensing assembly; 3013. Dynamic sealing assembly; 3014. Wire joint. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0025] The following specific embodiments are used to describe the technical solution of the present invention in detail. The following specific embodiments can be combined or replaced with each other according to actual conditions, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0026] Example 1

[0027] like Figures 1 to 5 As shown, the present invention provides a cable-controlled downhole injector for polymer injection and profile control, comprising an upper joint 1, an upper connecting pipe 2, an injector body 3, a lower connecting pipe 4, and a lower joint 5 connected in sequence from top to bottom, with a flow passage formed in the center thereof. Cable interfaces 6 are provided on both sides of the injector body 3, an upper threading pipe 7 and a lower threading pipe 8 are provided between the upper joint 1 and the upper connecting pipe 2, and between the lower joint 4 and the lower connecting pipe 5, respectively. A steel pipe cable 9 passes through the upper threading pipe 7 and the lower threading pipe 8, respectively, and is connected to the cable interface 6 via a cable joint 10.

[0028] The dispenser body 3 includes a central mounting body 301 eccentrically arranged on one side of the flow channel, a motor assembly 302 is provided on the left side of the central mounting body 301, and a flow test assembly 303 is provided on the right side. A transmission shaft 304, a transmission screw 305, a valve core 306 and a valve sleeve 307 are provided inside. A liquid outlet 308 is also provided on the central mounting body 301, and the liquid outlet 308 is provided at the left end of the valve sleeve 307. One end of the transmission shaft 304 is connected to the motor assembly 302, and the other end is connected to one end of the transmission screw 305. The other end of the transmission screw 305 is connected to the valve core 306 so that the valve core 306 can reciprocate along the direction of the valve sleeve 307. A plurality of annular pressure reducing grooves 309 are provided in the valve sleeve 307, and the right end of the valve sleeve 307 is connected to the flow test assembly 303.

[0029] The upper connector 1 and the lower connector 5 are connected to the dispenser body 3 through the upper connecting pipe 2 and the lower connecting pipe 4, and then the steel pipe cable 9 passes through the upper threading pipe 7 and the lower threading pipe 8 and is connected to the cable interface 6 through the cable connector 10. According to this installation method, the original need to set up separate cable installation interfaces at the upper and lower ends of the device and reserve the installation length of the cable connector is abandoned, thereby effectively shortening the overall length of the device; at the same time, the injection channel and the profile control channel are shared, and the position of the regulating valve core 306 is driven by the motor assembly 302 to realize the intelligent switching of the injection function and the profile control function, thereby simplifying the structural composition of the entire device, reducing product costs and improving product reliability;

[0030] Furthermore, the cable interfaces 6 are installed on both sides of the central mounting body 301 and arranged opposite to each other. The cable interfaces 6 on both sides are arranged respectively close to the upper connector 1 and the lower connector 5, and are arranged opposite to each other, which fully utilizes the radial space of the central mounting body 301 in terms of structure and optimizes space utilization.

[0031] Furthermore, in order to ensure that the polymer does not clog easily during long-term operation and to meet the requirements of later profile control of the polymer injection well, the flow channel design needs to be smooth and without large bends, so the flow channel angle of the flow test assembly 303 is less than 30°.

[0032] Furthermore, a first circuit assembly 3010 is disposed within the central mounting body 301, with a second circuit assembly 3011 disposed on the left side. The first circuit assembly 3010 and the second circuit assembly 3011 are electrically connected. The second circuit assembly 3011 and the motor assembly 302 are connected via a wire connector 11. The first circuit assembly 3010 is electrically connected to the flow measurement assembly 303. A pressure sensing assembly 3012 is also disposed within the central mounting body 301, electrically connected to the first circuit assembly 3011. The first circuit assembly 3010 and the second circuit assembly 3011 serve as the primary control units. The first circuit assembly 3010 is mounted within the central mounting body 301, fully utilizing the installation space within the central mounting body 301 and shortening the overall length of the instrument. Furthermore, the aforementioned functional modules are individually sealed. In addition to being electrically connected for communication and control, they are also spatially positioned via threaded connections. All functional modules are integrated into the dispenser body 3 and eccentrically positioned to one side of the flow channel, ensuring ample space for the channel.

[0033] Furthermore, a dynamic seal assembly 3013 is provided between the motor assembly 302 and the transmission shaft 304. As the main driving parts, the motor assembly 302 and the transmission shaft 304 need to avoid high pressure and immersion in the external medium, so the dynamic seal assembly is used for sealing protection to improve the reliability of the work.

[0034] Working principle of polymer injection and profile control:

[0035] like Figures 4 and 5 As shown, the motor assembly 302 drives the transmission shaft 304 to rotate and drives the transmission screw 305 to rotate. The transmission screw 305 rotates to drive the valve core 306 to reciprocate along the direction of the valve sleeve 307. The flow pressure difference is adjusted by adjusting the number of annular pressure-reducing grooves 309 matched between the valve core 306 and the valve sleeve 307 to control the flow rate of the injected polymer. When profile adjustment is required, the valve core 306 is controlled to move to the far left end. At this time, the liquid outlet 308 is completely exposed, and the minimum internal diameter of the entire flow channel meets the requirements of smooth passage of the profile adjustment agent particles.

[0036] In addition to the above-mentioned preferred embodiments, the present invention has other implementation modes. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection requested by the present invention.

Claims

1. A cable-controlled downhole injector for polymer injection and profile control, characterized in that: The invention comprises an upper joint (1), an upper connecting pipe (2), a dispenser body (3), a lower connecting pipe (4) and a lower joint (5) which are connected in sequence from top to bottom, and a flow passage is formed in the center of the inner portion. Cable interfaces (6) are provided on both sides of the dispenser body (3). An upper threading pipe (7) and a lower threading pipe (8) are provided between the upper joint (1) and the upper connecting pipe (2) and between the lower joint (4) and the lower connecting pipe (5), respectively. A steel pipe cable (9) passes through the upper threading pipe (7) and the lower threading pipe (8) and is connected to the cable interface (6) via a cable joint (10); The dispenser body (3) comprises a central mounting body (301) eccentrically arranged on one side of the flow channel, a motor assembly (302) being arranged on the left side of the central mounting body (301), a flow test assembly (303) being arranged on the right side, a transmission shaft (304), a transmission screw (305), a valve core (306) and a valve sleeve (307) being arranged inside the central mounting body (301), a liquid outlet (308) being provided on the central mounting body (301), the liquid outlet (308) being provided at the left end of the valve sleeve (307), one end of the transmission shaft (304) being connected to the motor assembly (302), and the other end being connected to one end of the transmission screw (305), the other end of the transmission screw (305) being connected to the valve core (306) so that the valve core (306) performs reciprocating motion along the direction of the valve sleeve (307), a plurality of annular pressure reducing grooves (309) being provided in the valve sleeve (307), and the right end of the valve sleeve (307) being communicated with the flow test assembly (303).

2. The cable-controlled downhole injector for polymer injection and profile control according to claim 1, characterized in that: The cable interfaces (6) are installed on both sides of the central installation body (301) and arranged opposite to each other.

3. The cable-controlled downhole injector for polymer injection and profile control according to claim 1, characterized in that: The flow channel angle of the flow testing component (303) is less than 30°.

4. The cable-controlled downhole injector for polymer injection and profile control according to claim 1, characterized in that: A first circuit assembly (3010) is further provided inside the central mounting body (301), and a second circuit assembly (3011) is provided on the left side. The first circuit assembly (3010) is electrically connected to the second circuit assembly (3011), the second circuit assembly (3011) is connected to the motor assembly (302) via a wire connector (3014), and the first circuit assembly (3010) is electrically connected to the flow test assembly (303).

5. The cable-controlled downhole injector for polymer injection and profile control according to claim 4, characterized in that: A pressure-sensing component (3012) is further provided inside the central installation body (301), and the pressure-sensing component (3012) is electrically connected to the first circuit component (3011).

6. The cable-controlled downhole injector for polymer injection and profile control according to claim 1, characterized in that: A dynamic sealing assembly (3013) is provided between the motor assembly (302) and the transmission shaft (304).

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