Ground intelligent layered polymer injection and water injection anti-sticking pipe column and process method

Abstract

The present application relates to ground intelligent layered polymer injection and water injection anti-sticking pipe column, including inner tube injection manifold, outer tube injection manifold, small tubing hanger, large tubing hanger, outer layer large tubing, inner layer small tubing;Small tubing hanger connects inner layer small tubing, and suspends and fixes inner layer small tubing on Christmas tree, and inner tube injection manifold is connected with small tubing hanger;Large tubing hanger connects outer layer large tubing, and suspends and fixes outer layer large tubing on Christmas tree, and outer tube injection manifold is connected with large tubing hanger;Inner tube injection manifold is fixedly connected with inner tube intelligent control valve and upper layer pressure gauge, and outer tube injection manifold is fixedly connected with outer tube intelligent control valve and lower layer pressure gauge;Inner tube intelligent control valve and outer tube intelligent control valve are all communicated with host computer through communication module;The present application can realize injection optimization adjustment of each layer according to the production dynamic of monitoring in time, improves polymer flooding or water flooding development effect.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of oilfield separate layer polymer injection or water injection, and particularly relates to a ground intelligent separate layer polymer injection and water injection anti-stuck pipe column and process method. BACKGROUND

[0002] At present, the single pipe column separate injection process is mainly used in the oilfield separate layer polymer injection or water injection well, and the test and adjustment are performed through the wireline or cable operation. However, the downhole mechanical contact type control separate injection of the single pipe column still has a large resistance and sticking risk, especially for the separate injection well with the inclination of > 50°, the test and adjustment of the wireline and cable downhole is difficult; at the same time, the polymer flooding needs to consider not only the injection amount of each layer, but also the matching problem of the permeability of each layer system and the relative molecular mass of the polymer, the polymer with small relative molecular mass has small resistance coefficient in the high permeability layer, and is easy to surge along the high permeability layer, and the oil displacement efficiency is low; and the increase of the relative molecular mass of the polymer is easy to cause the blockage of the middle and low permeability layer. For the different permeability oil layers of the heterogeneous reservoir, the corresponding polymer system and injection allocation need to be selected, and therefore the single pipe column separate layer polymer injection process cannot meet the needs of the polymer flooding. The current applied double pipe separate injection process has the risks of formation sand production, polymer return and other blockage of the injection channel, and the large repair caused by the stuck pipe column, and cannot real-time monitor the injection amount and pressure change of each layer, and lacks the judgment basis of the layer adjustment, and cannot timely realize the injection optimization adjustment of each layer. SUMMARY

[0003] The purpose of the present application is to provide a ground intelligent separate layer polymer injection and water injection anti-stuck pipe column and process, which effectively avoids the risks of formation sand production, polymer return and other blockage of the injection channel, and the large repair caused by the stuck pipe column by separately injecting two layers through two independent anti-stuck pipe columns, the downhole pressures do not interfere with each other, the polymer viscosity and flow rate and the like can be dynamically adjusted according to the different permeability layers, the ground remote real-time control adjustment and monitoring of the injection amount, injection pressure and other parameters of each layer are realized, the manual fishing test and adjustment operation is avoided, the injection optimization adjustment of each layer can be timely realized according to the monitored production dynamic, and the development effect of the polymer flooding or water flooding is improved.

[0004] The technical problem of the present application is solved by adopting the following technical scheme:

[0005] The ground intelligent separate layer polymer injection and water injection anti-stuck pipe column comprises an inner pipe injection manifold, an outer pipe injection manifold, a small oil pipe hanger, a large oil pipe hanger, an outer layer large oil pipe and an inner layer small oil pipe.

[0006] The small tubing hanger connects to the inner small tubing and suspends and fixes it to the Christmas tree. The inner tubing injection manifold is connected to the small tubing hanger. The large tubing hanger connects to the outer large tubing and suspends and fixes it to the Christmas tree. The outer tubing injection manifold is connected to the large tubing hanger. An inner tubing intelligent control valve and an upper pressure gauge are fixedly connected to the inner tubing injection manifold. An outer tubing intelligent control valve and a lower pressure gauge are fixedly connected to the outer tubing injection manifold.

[0007] Both the inner and outer intelligent control valves include a circuit control module, a communication module, and a polymer / water injection regulation mechanism. The polymer / water injection regulation mechanism includes a drive module, a throttling core, and a throttling sleeve. The throttling core is composed of multiple smooth, spindle-shaped rods arranged in descending order of size connected in series. A frustum-shaped inner channel is formed within the throttling sleeve. The drive module drives the throttling core to move, thereby increasing or decreasing the gap between the throttling core and the inner channel, thus regulating the injection volume. The throttling core, in conjunction with the inner channel, can completely close the inner channel. An outlet and an inlet are formed at the two ends of the inner channel on the throttling sleeve, respectively. A first pressure monitor is installed at the outlet, and a flow detector and a second pressure monitor are installed at the inlet. The drive module, the first pressure monitor, the flow detector, and the second pressure monitor are electrically connected to the circuit control module, which communicates with a host computer through the communication module.

[0008] Furthermore, the inner small tubing is located inside the outer large tubing, and one end of both is inserted into the casing. The outer large tubing, located inside the casing, is sequentially fixed with a series-connected backwash valve, a mechanically set packer to prevent top-mounting, a hydraulically retrievable bridge plug, and an insertion sealing injector.

[0009] Furthermore, the insertion sealing injector includes an upper connector, a central tube, an outer cylinder, and a lower connector. The upper and lower connectors are respectively connected to the outer large oil pipe. The two ends of the outer cylinder are respectively connected to the upper and lower connectors. The central tube is fixedly installed inside the outer cylinder and passes through the central tube to form an inner tube injection channel with the outer cylinder. A ball valve structure is formed in the central tube upstream of the inner tube injection channel. The ball valve structure includes a sealing ball and an inner sliding sleeve. The inner sliding sleeve is fixed to the inner wall of the central tube by shear pins, and the sealing ball and the inner wall of the inner sliding sleeve are sealed together.

[0010] Furthermore, the ball valve structure has a central tube sealed and fixedly connected to an insert tube, which is fixedly connected to an insert tube connector, and the other end of the insert tube connector is connected to the inner layer small oil tube.

[0011] Furthermore, a flow channel is formed between the central tube and the outer cylinder, and the flow channel bridges the inner channels of the upper and lower connectors, through which mechanical impurities are deposited.

[0012] Further, the end of the insertion sealing distributor is fixedly connected with a tail pipe, and a plug is installed at the end of the tail pipe.

[0013] Further, a tubing head wing is installed on the casing, and a tubing head pressure gauge is installed on the tubing head wing.

[0014] Further, the upper pressure gauge, the lower pressure gauge and the tubing head pressure gauge respectively display the pressure of the inner small tubing, the outer large tubing and the casing.

[0015] Further, the hydraulic retrievable bridge plug has a releasing structure, and can be released from the upper pipe column by applying a certain pulling force after being set.

[0016] The layered polymer injection and water injection process method using the ground intelligent layered polymer injection and water injection anti-stuck pipe column comprises the following steps:

[0017] The outer large tubing is lowered into the casing, and a backwashing valve, a mechanically-set anti-uplifted packer, a hydraulic retrievable bridge plug, an insertion sealing distributor and a tail pipe are fixedly connected in sequence at the end of the outer large tubing; the hydraulic retrievable bridge plug is set and sealed; the outer large tubing is lifted to release the hydraulic retrievable bridge plug from the upper pipe column; and the outer large tubing is lifted to a suitable position, the mechanically-set anti-uplifted packer is set and sealed.

[0018] The inner small tubing is lowered into the outer large tubing, and a pipe connector and a pipe are fixedly connected in sequence at the bottom end of the inner small tubing; the pipe is inserted into the center pipe, and whether the pipe is successfully and fixedly connected with the center pipe is verified.

[0019] The first oil layer is injected with polymer or water through the inner pipe injection manifold, the inner layer small tubing, the pipe and the inner pipe injection channel of the insertion sealing distributor; according to the injection amount of the first oil layer, the upper computer and the inner pipe intelligent control valve are cooperated to intelligently control the injection amount; the second oil layer is injected with polymer or water through the outer pipe injection manifold, the annulus between the outer large tubing and the inner layer small tubing, the annulus between the mechanically-set anti-uplifted packer and the inner layer small tubing; according to the injection amount of the second oil layer, the upper computer and the outer pipe intelligent control valve are cooperated to intelligently control the injection amount; and in the injection process, the impurities on the inner wall of the outer large tubing and the impurities returned from the second oil layer are deposited into the tail pipe through the overflow channel of the insertion sealing distributor.

[0020] The advantages and positive effects of the present application are as follows:

[0021] The present application realizes two-layered separate layer polymer injection, separate layer water injection and separate layer profile control through two sets of independent anti-stuck pipe columns, effectively avoids the risk of pipe column sticking caused by sand production, polymer backflow and other factors, and is particularly suitable for separate layer polymer injection, separate layer profile control and separate layer water injection of wells with easy backflow; the downhole pressures do not interfere with each other, the viscosity and flow rate of injected polymer or profile control agent can be dynamically adjusted according to different permeability intervals, the ground remote control adjusts and monitors the injection rate, injection pressure and other parameters, and can timely optimize and adjust the injection dynamic of each interval according to the monitored data, improve the polymer flooding or water flooding development effect, realizes artificial free fishing and measuring and adjusting operation, reduces the cost and labor intensity of measuring and adjusting operation, and improves the production efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0022] The technical solutions of the present application will be further described in detail below in combination with the drawings and examples, but it should be understood that these drawings are designed only for illustrative purposes, and therefore do not limit the scope of the present application. In addition, unless specifically indicated, these drawings are only intended to conceptually illustrate the structural configuration described herein, and do not necessarily be drawn to scale.

[0023] Fig. 1 is a structural schematic diagram of the ground intelligent separate layer polymer injection and water injection anti-stuck pipe column provided by the embodiment of the present application;

[0024] Fig. 2 is a structural schematic diagram of the insertion sealing and injection device of the ground intelligent separate layer polymer injection and water injection anti-stuck pipe column provided by the embodiment of the present application;

[0025] Fig. 3 is a structural schematic diagram of the polymer / water injection control mechanism of the ground intelligent separate layer polymer injection and water injection anti-stuck pipe column provided by the embodiment of the present application; DETAILED DESCRIPTION

[0026] First of all, it should be noted that the specific structure, features and advantages of the present application will be specifically described below by way of example, however, all the descriptions are only used for illustration, and should not be understood as any limitation on the present application. In addition, any single technical feature described or implied in each embodiment mentioned in the present application, or any single technical feature shown or implied in each drawing, can still continue to be combined or deleted between these technical features (or their equivalents), so as to obtain more other embodiments of the present application which can not be directly mentioned in the present application. In addition, in order to simplify the drawing, the same or similar technical features can only be marked in one place in the same drawing.

[0027] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly used when the product of the application is used, and are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the application.

[0028] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0029] As Figs. 1 to 3 , the embodiment provides a ground intelligent layered polymer injection and water injection anti-sticking pipe column, which comprises an inner pipe injection manifold 1, an outer pipe injection manifold 4, a small tubing hanger 9, a large tubing hanger 10, an outer large tubing 12 and an inner small tubing 13.

[0030] The small tubing hanger 9 is connected with the inner small tubing 13 and suspends and fixes the inner small tubing 13 on the Christmas tree, the inner pipe injection manifold 1 is through-connected with the small tubing hanger 9; the large tubing hanger 10 is connected with the outer large tubing 12 and suspends and fixes the outer large tubing 12 on the Christmas tree, the outer pipe injection manifold 4 is through-connected with the large tubing hanger 10; the inner pipe injection manifold 1 is fixedly connected with an inner pipe intelligent control valve 2 and an upper layer pressure gauge 3, and the outer pipe injection manifold 4 is fixedly connected with an outer pipe intelligent control valve 5 and a lower layer pressure gauge 6.

[0031] The inner tube intelligent control valve 2 and the outer tube intelligent control valve 5 both comprise a circuit control module, a communication module and an injection polymer / water regulating mechanism, the injection polymer / water regulating mechanism comprises a driving module 2501, a throttling core 2506 and a throttling sleeve 2507, the throttling core 2506 is composed of a plurality of smooth shuttle-shaped rods arranged from large to small in series, which can greatly reduce the shear of high-molecular organic matters such as polymer and profile control agent; the throttling sleeve 2507 forms a circular truncated cone-shaped inner hole, the driving module 2501 drives the throttling core 2506 to move through a transmission shaft 2504, so as to increase or decrease the gap between the throttling core 2506 and the inner hole, thereby regulating the injection amount, and the throttling core 2506 cooperates with the inner hole to completely close the inner hole; the two ends of the inner hole form an outlet 2505 and an inlet 2508 on the throttling sleeve 2507 respectively, a first pressure monitor 2503 is installed at the outlet 2505, a flow detector and a second pressure monitor 2509 are installed at the inlet 2508, the driving module 2501, the first pressure monitor 2503, the flow detector and the second pressure monitor 2509 are electrically connected with the circuit control module respectively, the circuit control module is communicatively connected with the upper computer through the communication module, and it can be considered that a sealing sleeve 2502 is also installed in the injection polymer / water regulating mechanism, the sealing sleeve 2502 is installed at the driving module 2501, the sealing sleeve 2502 protects the driving module 2501 and prevents liquid from entering; the first pressure monitor 2503 monitors the pressure of the outlet 2505 and feeds back the monitoring data to the circuit control module; the flow detector (not shown in the figure) and the second pressure monitor 2509 can monitor the flow and pressure of the inlet 2508, that is, monitor the injection pressure and flow of the inner tube injection manifold 1, and feed back the monitoring data to the circuit control module, the circuit control module transmits the above-mentioned data received to the upper computer through the communication module; the upper computer can issue remote control instructions through the communication module and transmit them to the circuit control module to control the driving module 2501 to work. It should be pointed out that the driving module 2501 can adopt a motor in cooperation with a speed reducer, and the upper computer can adopt an intelligent computer, an intelligent mobile phone and the like in cooperation with software, the inner tube intelligent control valve 2 and the outer tube intelligent control valve 5 have the functions of automatic injection amount allocation and injection parameter collection, rely on external power supply for power supply, and can implement bidirectional communication with the remote control software on the upper computer.

[0032] The inner layer small oil pipe 13 is located inside the outer layer large oil pipe 12, and one end of both is lowered into the casing 11, and the end of the outer layer large oil pipe 12 in the casing is sequentially fixed with a sealed series reverse flushing well valve 14, a mechanically set anti-uplift packer 15, a hydraulic retrievable bridge plug 16 and an inserted sealing injection device 17.

[0033] Specifically, the insertion sealing injection device 17 comprises an upper joint 1701, a central pipe 1702, an outer cylinder 1703, and a lower joint 1710. The upper joint 1701 and the lower joint 1710 are respectively threadedly and sealingly connected with the outer large oil pipe 12. The outer cylinder 1703 is threadedly and sealingly connected with the upper joint 1701 and the lower joint 1710 at both ends. The central pipe 1702 is fixedly installed inside the outer cylinder 1703. An inner pipe injection channel 1709 is formed by passing through the central pipe 1702 and the outer cylinder 1703. A ball valve structure is formed in the central pipe upstream of the inner pipe injection channel 1709. The ball valve structure comprises a sealing ball 1706 and an inner sliding sleeve 1707. The inner sliding sleeve 1707 is fixed on the inner wall of the central pipe 1702 by a shear pin 1708. The sealing ball 1706 is sealingly matched with the inner wall of the inner sliding sleeve 1707.

[0034] A plug 1802 is sealingly and fixedly connected in the central pipe upstream of the ball valve structure. The plug 1802 is sealingly and fixedly connected with a plug joint 1801. The other end of the plug joint 1801 is threadedly and sealingly connected with the inner small oil pipe 13. It can be considered that a sealing rubber sleeve 1705 is installed on the inner wall of the central pipe 1702. The plug 1802 is sealingly matched with the central pipe through the sealing rubber sleeve 1705. A sealing ring is arranged on the shear pin 1708 to block the communication between the inner flow channel 1704 and the inside of the central pipe 1702. After the shear pin 1708 is sheared by pushing the inner sliding sleeve 1707 on the sealing ball 1706 under the action of liquid pressure, the inner sliding sleeve 1707 moves to the lower end of the inner pipe injection channel 1709, and the inner pipe injection channel 1709 is opened. The inner pipe injection channel 1709 bridge-communicates the inner channel of the central pipe 1702 and the outer space of the outer cylinder 1703.

[0035] A flow channel 1704 is formed between the central pipe and the outer cylinder. The flow channel 1704 bridge-communicates the inner channels of the upper joint 1701 and the lower joint 1710. Mechanical impurities such as iron rust and sand are deposited in the flow channel 1704.

[0036] A tail pipe 19 is fixedly connected to the end of the insertion sealing injection device 17. A plug 20 is installed at the end of the tail pipe 19. The tail pipe 19 is threadedly and sealingly connected with the plug 20 to form a closed space.

[0037] An oil pipe head wing 7 is installed on the side wall of the casing 11. An oil pipe head pressure gauge 8 is installed on the oil pipe head wing 7. The oil pipe head wing 7 is used for pressure release and backwashing of the casing 11. The upper layer pressure gauge 3, the lower layer pressure gauge 6, and the oil pipe head pressure gauge 8 respectively display the pressures of the inner small oil pipe 13, the outer large oil pipe 12, and the casing 11.

[0038] And, it needs to be explained that the hydraulic retrievable bridge plug 16 has a releasing structure, and can be set by hydraulic pressure, has a two-way slip anchored on the inner wall of the casing 11, can bear high pressure difference water injection, and can be released by applying a certain pulling force after setting, and can be separated from the upper string.

[0039] It can be understood that the inner diameter of the outer large oil pipe 12 is greater than the maximum outer diameter of the inner small oil pipe 13 and the insert pipe 1802; the reverse flow valve 14 has a one-way flow channel opened from the outside to the inside, allowing high-pressure fluid in the casing 11 to enter the outer large oil pipe 12 through the one-way flow channel, but preventing fluid in the outer large oil pipe 12 from entering the casing 11 through the one-way flow channel, for later workover circulation and well killing operation; the mechanical setting anti-upsetting packer 15 is mechanically set and released, has a two-way slip anchored on the inner wall of the casing 11 during water injection, prevents pipe string creep, and can bear high pressure difference water injection; the inner diameters of the reverse flow valve 14, the mechanical setting anti-upsetting packer 15, and the hydraulic retrievable bridge plug 16 are all greater than the maximum outer diameter of the inner small oil pipe 13 and the insert pipe 1802;

[0040] The layered polymer injection and water injection process method using the ground intelligent layered polymer injection and water injection anti-stuck pipe string includes the following steps:

[0041] Hydraulic retrievable bridge plug 16 setting and sealing: the hydraulic retrievable bridge plug 16, the insert sealing and injection device 17, the tail pipe 19, and the plug 20 are lowered to the designed position; pressure is applied from the outer large oil pipe 12, the pressure is transmitted to the hydraulic retrievable bridge plug 16 and the sealing ball 1706 in the insert sealing and injection device 17 through the inner channel of the reverse flow valve 14 and the mechanical setting anti-upsetting packer 15, the hydraulic retrievable bridge plug 16 is set and fixed on the casing 11 under hydraulic pressure, and the first oil layer A and the second oil layer B are sealed apart; the pressure is continuously increased to push the sealing ball 1706 and the inner sleeve 1707 to cut the shear pin 1708, open the inner pipe injection channel 1709, pump liquid into the outer large oil pipe 12, and the oil pipe head flange 7 does not return liquid, which proves that the hydraulic retrievable bridge plug 16 is sealed qualified;

[0042] Mechanical setting anti-upsetting packer 15 setting and sealing: the outer large oil pipe 12 is lifted, a certain pulling force is applied, the hydraulic retrievable bridge plug 16 is separated from the upper string, the reverse flow valve 14 and the mechanical setting anti-upsetting packer 15 are lifted to the designed position, the mechanical setting anti-upsetting packer 15 is set, liquid is pumped into the outer large oil pipe 12, and the oil pipe head flange 7 does not return liquid, which proves that the mechanical setting anti-upsetting packer 15 is sealed qualified;

[0043] Insertion of the insert pipe 1802: after the outer large oil pipe 12 is fixed and sealed to the large oil pipe hanger 10 and is suspended and fixed on the Christmas tree, the small oil pipe hanger 9 cross is installed, and then the inner small oil pipe 13 is lowered from the outer large oil pipe 12, the bottom end of the inner small oil pipe 13 is fixed and sealed to the insert pipe 1802, the insert pipe 1802 is inserted into the central pipe 1702 of the insert sealing flow distributor 17 and is sealed with the sealing rubber sleeve 1705, and then the small oil pipe hanger 9 is suspended and fixed on the Christmas tree through fixed sealing; the pump truck is used to pump liquid into the inner small oil pipe 13, and if the annulus between the outer large oil pipe 12 and the inner small oil pipe 13 has no return liquid, it is proved that the insert pipe 1802 is successfully inserted into the insert sealing flow distributor 17 and is sealed with the sealing rubber sleeve 1705;

[0044] Layered injection: the wellhead Christmas tree and the inner pipe injection manifold 1, the inner pipe intelligent control valve 2, the upper layer pressure gauge 3, the outer pipe injection manifold 4, the outer pipe intelligent control valve 5, the lower layer pressure gauge 6, the tubing head pressure gauge 8 are installed; 11 from the inner pipe injection manifold 1, through the small oil pipe hanger 9, the inner small oil pipe 13, the insert pipe 1802, the inner pipe injection channel 1709 of the insert sealing flow distributor 17, the lower oil layer is injected, according to the injection allocation of the first oil layer, the gap between the throttle core 2506 and the throttle sleeve 2507 in the inner pipe intelligent control valve 2 is intelligently adjusted, so as to intelligently control the injection amount of the first oil layer A; from the outer pipe injection manifold 4, through the annulus between the large oil pipe hanger 10, the outer large oil pipe 12 and the inner small oil pipe 13, the annulus between the inner channel of the mechanically set and sealed anti-uplift packer 15 and the inner small oil pipe 13, the second oil layer is injected, according to the injection allocation of the second oil layer, the gap between the throttle core 2506 and the throttle sleeve 2507 in the outer pipe intelligent control valve 5 is intelligently adjusted, so as to intelligently control the injection amount of the second oil layer; during the injection process, the mechanical impurities such as iron rust on the inner wall of the outer large oil pipe 12 and the formation sand returned by the second oil layer are deposited into the tail pipe 19 through the overflow channel 1704 on the insert sealing flow distributor 17, so as to avoid the blockage of the injection channel and the embedding of the insert pipe 1802.

[0045] Real-time regulation and monitoring of production state: the inner tube intelligent control valve 2 and the outer tube intelligent control valve 5 can communicate with the upper computer, automatically adjust the gap between the throttle core 2506 and the throttle sleeve 2507, intelligently control the injection amount, realize the automatic intelligent allocation of the first oil layer and the second oil layer injection amount, and continuously monitor the outlet 2505 pressure dynamic, the flow detector, and the inlet 2508 flow and pressure dynamic monitored by the pressure monitor 2509 through the network back to the upper computer, to realize remote real-time monitoring of the layered injection dynamic; when the production state is abnormal, timely diagnosis and alarm prompt; the upper computer can directly instruct the inner tube intelligent control valve 2 and the outer tube intelligent control valve 5 to increase or decrease the gap between the throttle core 2506 and the throttle sleeve 2507, increase or decrease the injection amount, or instruct the inner tube intelligent control valve 2 or the outer tube intelligent control valve 5 to close, to realize remote real-time regulation of the layered production dynamic.

[0046] Late workover operation: after stopping injection and pressure relief, first pump kill fluid from the tubing head wing 7 to the casing 11, enter the annulus between the outer large tubing 12 and the inner small tubing 13 through the one-way well flushing channel of the reverse flushing valve 14, return from the outer tube injection manifold 4, form a circulating reverse flushing well killing; if necessary, the inner tube injection manifold 1 can be used to squeeze well fluid into the first oil layer through the small tubing hanger 9, the inner small tubing 13, the insertion pipe 1802, and the inner tube injection channel 1709 of the insertion sealing injection device 17, and after the well killing is qualified, first disassemble the inner tube injection manifold 1, the inner tube intelligent control valve 2, the upper layer pressure gauge 3, the outer tube injection manifold 4, the outer tube intelligent control valve 5, the lower layer pressure gauge 6, the tubing head pressure gauge 8, and the wellhead Christmas tree, then remove the small tubing hanger 9, the inner small tubing 13, the insertion pipe 1802, and then disassemble the small tubing hanger 9 cross. Then keep the inner and outer pressure difference of the mechanically set anti-upset packer 15 balanced, raise the large tubing hanger 10 to make the mechanically set anti-upset packer 15 retract the two-way slips and complete the unblocking, remove the large tubing hanger 10, the outer large tubing 12, the well flushing valve 14, and the mechanically set anti-upset packer 15. Finally, lower the fishing string, probe and flush the sand, and then fish out the hydraulic retrievable bridge plug 16, the insertion sealing injection device 17, the tail pipe 19, and the plug 20, avoiding the risk of pipe string stuck caused by formation sand return, polymer, etc.

[0047] The above embodiments have been described in detail, but the content described is only the preferred embodiments of the present application, and cannot be considered as limiting the scope of the present application. Any equivalent changes and improvements made in the scope of the present application should still belong to the patent coverage of the present application.

Claims

1. Ground-based intelligent layered polymer injection and water injection anti-jamming pipe string, characterized in that: It includes an inner tube injection manifold (1), an outer tube injection manifold (4), a small tubing hanger (9), a large tubing hanger (10), an outer large tubing (12), and an inner small tubing (13). The small tubing hanger (9) connects to the inner small tubing (13) and suspends and fixes the inner small tubing (13) on the tree. The inner tubing injection manifold (1) is connected to the small tubing hanger (9). The large tubing hanger (10) connects to the outer large tubing (12) and suspends and fixes the outer large tubing (12) on the tree. The outer tubing injection manifold (4) is connected to the large tubing hanger (10). An inner tubing intelligent control valve (2) and an upper pressure gauge (3) are fixedly connected to the inner tubing injection manifold (1). An outer tubing intelligent control valve (5) and a lower pressure gauge (6) are fixedly connected to the outer tubing injection manifold (4). Both the inner tube intelligent control valve (2) and the outer tube intelligent control valve (5) include a circuit control module, a communication module, and an injection / water injection regulation mechanism. The injection / water injection regulation mechanism includes a drive module (2501), a throttling core (2506), and a throttling sleeve (2507). The throttling core (2506) is composed of multiple smooth shuttle-shaped rods arranged in descending order of size connected in series. The throttling sleeve (2507) forms a frustum-shaped inner channel. The drive module (2501) drives the throttling core (2506) to move, thereby increasing or decreasing the gap between the throttling core (2506) and the inner channel, thus regulating the injection volume. The flow core (2506) cooperates with the inner channel to completely close the inner channel; the two ends of the inner channel form an outlet (2505) and an inlet (2508) on the throttling sleeve (2507), respectively. A first pressure monitor (2503) is installed at the outlet (2505), and a flow detector and a second pressure monitor (2509) are installed at the inlet (2508). The drive module (2501), the first pressure monitor (2503), the flow detector and the second pressure monitor (2509) are electrically connected to the circuit control module, and the circuit control module communicates with the host computer through the communication module. The inner small tubing (13) is located inside the outer large tubing (12), and one end of both is lowered into the casing (11). The outer large tubing (12) located inside the casing is sequentially fixed with a series sealing backwash valve (14), a mechanically set packer to prevent top-mounting (15), a hydraulically retrievable bridge plug (16), and an insertion sealing injector (17). The insertion sealing injector (17) includes an upper connector (1701), a central tube (1702), an outer cylinder (1703), and a lower connector (1710). The upper connector (1701) and the lower connector (1710) are respectively connected to the outer layer large oil pipe (12). The two ends of the outer cylinder (1703) are respectively connected to the upper connector (1701) and the lower connector (1710). The central tube (1702) is fixedly installed inside the outer cylinder (1703). The central tube (1702) passes through the outer cylinder (1703) to form an inner tube injection channel (1709). A flow channel (1704) is formed between the central tube (1702) and the outer cylinder (1703). The flow channel (1704) bridges the inner channels of the upper connector (1701) and the lower connector (1710). Mechanical impurities are deposited through the flow channel (1704). The hydraulic retrievable bridge plug (16) has a release structure. After the setting is completed, a certain pulling force is applied to release it, which can detach it from its upper tubing. The end of the insertion sealing injector (17) is fixedly connected to the tail tube (19), and the end of the tail tube is fitted with a plug (20). The tail tube (19) and the plug (20) cooperate to form a closed space.

2. The ground-based intelligent layered polymer injection and water injection anti-jamming pipe string according to claim 1, characterized in that: A ball valve structure is formed in the central tube upstream of the inner tube injection channel (1709). The ball valve structure includes a sealing ball (1706) and an inner sliding sleeve (1707). The inner sliding sleeve (1707) is fixed on the inner wall of the central tube (1702) by a shear pin (1708). The sealing ball (1706) and the inner wall of the inner sliding sleeve (1707) are sealed together.

3. The ground-based intelligent layered polymer injection and water injection anti-jamming pipe string according to claim 2, characterized in that: The ball valve structure is sealed and fixedly connected to the insert tube (1802) in the central tube upstream. The insert tube is fixedly connected to the insert tube connector (1801), and the other end of the insert tube connector (1801) is connected to the inner small oil tube (13).

4. The ground-based intelligent layered polymer injection and water injection anti-jamming pipe string according to claim 1, characterized in that: The tubing head wing (7) is installed on the casing (11), and the tubing head pressure gauge (8) is installed on the tubing head wing (7). The tubing head wing (7) is used for depressurization of the casing (11) and backwashing to kill the well.

5. The ground-based intelligent layered polymer injection and water injection anti-jamming pipe string according to claim 4, characterized in that: The upper pressure gauge (3), lower pressure gauge (6), and tubing head pressure gauge (8) respectively display the pressure of the inner small tubing (13), the outer large tubing (12), and the casing (11).

6. A method for layered polymer injection and water injection process using the ground-based intelligent layered polymer injection and water injection anti-jamming pipe string according to any one of claims 1-5, characterized in that, Includes the following steps: The outer tubing (12) is lowered into the casing, and the backwash valve (14), mechanical set-top packer (15), hydraulically retrievable bridge plug (16), insertion sealing injector (17), tail pipe (19) and the plug (20) are sequentially fixed to the end of the outer tubing (12). The hydraulically retrievable bridge plug (16) is set and verified. The outer tubing (12) is lifted up so that the hydraulically retrievable bridge plug (16) is disengaged from the upper tubing string. The outer tubing (12) is lifted up to a suitable position, the mechanical set-top packer (15) is set and verified. The inner small oil pipe (13) is lowered into the outer large oil pipe (12), and the bottom end of the inner small oil pipe (13) is fixedly connected to the insertion joint (1801) and the insertion pipe (1802) in sequence. The insertion pipe (1802) is inserted into the central pipe (1702), and it is verified whether the insertion pipe (1802) is successfully sealed and fixedly connected to the central pipe (1702). Polymer or water is injected into the first oil layer from the inner tube injection manifold (1) through the inner small oil pipe (13), the insertion pipe (1802), and the inner tube injection channel (1709) of the insertion sealing injector (17). According to the injection volume of the first oil layer, the host computer and the inner tube intelligent control valve (2) cooperate to intelligently regulate the injection volume. Polymer or water is injected into the second oil layer from the outer tube injection manifold (4) through the annulus between the outer large oil pipe (12) and the inner small oil pipe (13), the inner channel of the mechanical seated anti-top packer (15) and the inner small oil pipe (13). According to the injection volume of the second oil layer, the host computer and the outer tube intelligent control valve (5) cooperate to intelligently regulate the injection volume. During the injection process, impurities falling off the inner wall of the outer large oil pipe (12) and impurities returned from the second oil layer are deposited into the tail pipe (19) through the flow channel (1704) on the insertion sealing injector (17).

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