Anti-backflow closed water injection tubular column structure
By adopting an anti-backflow sealed injection tubing structure in the stratified injection wells and using a sliding sleeve switch to control the circulation channel, unidirectional injection is achieved, solving the problem of backflow at the bottom layer of the stratified injection wells and improving the success rate of testing and adjustment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-22
- Publication Date
- 2026-03-27
AI Technical Summary
The bottom layer of the existing stratified water injection well cannot achieve the backflow prevention function, which causes the injected water to backflow into the oil pipe, causing blockage and affecting the success rate of testing and commissioning.
The system adopts a closed-loop water injection pipe column structure to prevent backflow, including a plug, normally open sliding sleeve, pressure compensator, normally closed sliding sleeve, first and second anti-backflow water distributors and a packer. The circulation channel is controlled by the sliding sleeve switch to achieve unidirectional injection and eliminate the bottom single-flow ball seat to prevent backflow.
It effectively prevents injected water from flowing back, protects the injection tubing and casing, ensures the smooth deployment of testing and adjustment instruments in stratified injection wells, and improves the success rate of testing and adjustment.
Smart Images
Figure CN224049154U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to an oil extraction equipment, more exactly, it is a kind of anti-returning closed water injection pipe column structure. BACKGROUND
[0002] Water injection development is a widely used development method in oilfield development, and the separate layer water injection is the main technical means to solve interlayer contradiction and realize balanced water flooding. The separate layer water injection technology is to inject corresponding number of water distributor in the water injection wellbore according to the requirement of separate layer section number in water flooding development, and to realize separate layer quantitative injection by adjusting the opening degree of different water distributor. In the daily production of water injection well, the pump often jumps and stops, and the wellhead choke valve fails, which leads to the return of formation in high-pressure water injection well, the reflux of injected water and the blockage of dirty matter such as mud sand in the water injection pipe column. At present, the main solution to this problem is to improve the water distributor, and to install a choke structure on the water outlet outside the water nozzle of the water distributor to realize the anti-returning function.
[0003] At present, the lowermost layer of the separate layer water injection well cannot realize the anti-returning function. The bottom end of the water injection pipe column is a reverse choke ball seat to realize the reverse well flushing requirement during the pipe column lowering into the well and the positive pressure requirement for setting packer after the pipe column is in place. Therefore, the lowermost layer of water injection section cannot play the anti-returning role of the anti-returning water distributor, and the injected water in the lowermost layer will return into the oil pipe through the bottom end of the water injection pipe column when stopping injection. UTILITY MODEL CONTENT
[0004] Therefore, it is necessary to provide an anti-returning closed water injection pipe column structure aiming at the above technical problems.
[0005] In order to solve the above technical problems, the utility model adopts the following technical solutions:
[0006] An anti-returning closed water injection pipe column structure, characterized in that the anti-returning closed water injection pipe column structure comprises a plug, the upper part of the plug is provided with a lower tail pipe, the upper part of the tail pipe is provided with a normally open sliding sleeve, the upper part of the normally open sliding sleeve is provided with a pressure compensator, the upper part of the pressure compensator is provided with a normally closed sliding sleeve, the upper part of the normally closed sliding sleeve is provided with a first anti-returning water distributor, the upper part of the anti-returning water distributor is provided with a packer, the upper part of the packer is provided with a second anti-returning water distributor, and the upper part of the second anti-returning water distributor is provided with an oil pipe.
[0007] As a preferred embodiment of the utility model, the plug, the normally open sliding sleeve, the pressure compensator, the normally closed sliding sleeve, the first anti-returning water distributor, the packer and the second anti-returning water distributor are all arranged in the casing.
[0008] As a preferred embodiment of the utility model, the first anti-returning water distributor is located in the lower water injection layer, and the second anti-returning water distributor is located in the upper water injection layer.
[0009] As a preferred embodiment of the utility model, the oil pipe connecting well head.
[0010] Compared with the prior art, the utility model has the following beneficial effects:
[0011] The utility model provides a kind of anti-return closed water injection pipe column structure, which cancels the bottom single-flow ball seat in prior art, adopts sliding sleeve switch to control the opening and closing of circulation passage, realizes one-way injection, effectively prevents interlayer interference and injection water return when stopping injection.The anti-return closed water injection pipe column structure can realize one-way closed water injection, solve the problem of backflow at the bottom of traditional layered water injection pipe column, effectively prevent injection water backflow caused by improper ground management, avoid sand from formation into the interior of water injection pipe column, protect water injection pipe column and casing, ensure layered water injection well measuring and regulating instrument to be successfully lowered into well, improve measuring and regulating success rate, and have strong practicality. BRIEF DESCRIPTION OF DRAWINGS
[0012] To more clearly illustrate the scheme in the utility model, the following will make a simple introduction to the drawings needed to be used in embodiment description, and obviously, the drawings in the following description are some embodiments of the utility model, and for those skilled in the art, other drawings can also be obtained according to these drawings without creative labor.
[0013] Figure 1 It is the structure diagram of anti-return closed water injection pipe column structure of the utility model;
[0014] Figure 2 It is the structure diagram of normally closed sliding sleeve in Figure 1 ;
[0015] Figure 3 It is the structure diagram of pressure compensator in Figure 1 ;
[0016] Figure 4 It is the structure diagram of normally open sliding sleeve in Figure 1 ;
[0017] Markings in the drawing are as follows: 1, plug; 2, lower tail pipe; 2S, oil pipe; 3, normally open sliding sleeve; 4, pressure compensator; 5, normally closed sliding sleeve; 6, first anti-return water distributor; 6S, second anti-return water distributor; 7, packer; L1, lower water injection layer; L2, upper water injection layer; 8, casing. DETAILED DESCRIPTION
[0018] To enable those skilled in the art to better understand the scheme of the utility model, the following will combine the drawings in the embodiment of the utility model to make clear and complete description to the technical scheme in the embodiment of the utility model.
[0019] As Figures 1 to 4 shown, the anti-backflow sealed water injection pipe column structure comprises a plug 1, the upper part of the plug 1 is provided with a lower tail pipe 2, the upper part of the tail pipe 2 is provided with a normally open sliding sleeve 3, the upper part of the normally open sliding sleeve 3 is provided with a pressure compensator 4, the upper part of the pressure compensator 4 is provided with a normally closed sliding sleeve 5, the upper part of the normally closed sliding sleeve 5 is provided with a first anti-backflow water distributor 6, the upper part of the anti-backflow water distributor 6 is provided with a packer 7, the upper part of the packer 7 is provided with a second anti-backflow water distributor 6S, and the upper part of the second anti-backflow water distributor 6S is provided with a tubing 2S.
[0020] The plug 1, the normally open sliding sleeve 3, the pressure compensator 4, the normally closed sliding sleeve 5, the first anti-backflow water distributor 6, the packer 7 and the second anti-backflow water distributor 6S are all arranged in a casing 8.
[0021] The first anti-backflow water distributor 6 is located in a lower injection layer L1, and the second anti-backflow water distributor 6S is located in an upper injection layer L2.
[0022] The working mode of the anti-backflow sealed water injection pipe column structure will be described below.
[0023] During the process of lowering the pipe column into the well, the normally open sliding sleeve 3 is in an open state, and the normally closed sliding sleeve 5 is in a closed state. The circulation hole of the normally open sliding sleeve 3 can realize the function of positive and reverse circulation well flushing to adapt to the resistance encountered during the process of lowering the water injection pipe column into the well and the requirement of circulation well flushing. After the water injection pipe column is in place, a steel ball with a diameter of 22 mm is thrown from the ground, and the ball is waited to be in place. The normally open sliding sleeve 3 is closed by the tubing positive pressure, and the pressure is continuously increased to the packer setting pressure, and the separate layer water injection pipe column is completed.
[0024] After the normally open sliding sleeve 3 is closed, the anti-backflow water distributor 6 is matched to realize the full sealing of the water injection pipe column, realize the one-way injection of the injected water from the inside of the tubing to the formation, and effectively prevent the backflow of the formation.
[0025] During the next pipe inspection operation, the operation mode with pressure or the operation mode after the diffusion pressure is released in advance can be adopted. If the wellhead control pressure release mode is required to release the pressure, the upper injection layer L2 is controlled to release the pressure through the casing gate of the ground water injection wellhead. When the lower injection layer L1 is released, a steel ball with a diameter of 30 mm is thrown into the tubing, and the ball is waited to be in place. The normally closed sliding sleeve 5 is opened by the tubing positive pressure. In this process, the pressure compensator 4 plays a role in assisting the opening of the normally closed sliding sleeve 5. Then, the inside of the tubing is communicated with the lower injection layer L1, the pressure is released by the ground wellhead control, and the well control safety of the operation well is realized.
[0026] The anti-backflow sealed water injection pipe column structure cancels the bottom single-flow ball seat in the prior art, adopts the sliding sleeve switch to control the opening and closing of the circulation channel, realizes one-way injection, effectively prevents the interlayer interference and the backflow of the injected water during the stop injection, and has the advantages of simple structure, convenient operation, low cost, and the like.
[0027] The anti-backflow sealed water injection pipe column structure can realize one-way sealed water injection, solves the backflow problem at the bottom of the traditional separate layer water injection pipe column, effectively prevents the backflow of injected water caused by improper ground management, avoids the sand from the formation into the inside of the water injection pipe column, protects the water injection pipe column and the casing, ensures the smooth downhole of the separate layer water injection well measurement and regulation instrument, improves the measurement and regulation success rate, and has strong practicality.
[0028] Obviously, the above-described embodiments are only some of the embodiments of the present application, not all the embodiments, and the preferred embodiments of the present application are given in the drawings, but do not limit the patent scope of the present application.
Claims
1. A gagging and containment water injection string structure, characterized by, The anti-backflow closed water injection pipe column structure comprises a plug (1), the upper portion of the plug (1) is provided with a lower tail pipe (2), the upper portion of the tail pipe (2) is provided with a normally open sliding sleeve (3), the upper portion of the normally open sliding sleeve (3) is provided with a pressure compensator (4), the upper portion of the pressure compensator (4) is provided with a normally closed sliding sleeve (5), the upper portion of the normally closed sliding sleeve (5) is provided with a first anti-backflow water distributor (6), the upper portion of the anti-backflow water distributor (6) is provided with a packer (7), the upper portion of the packer (7) is provided with a second anti-backflow water distributor (6S), and the upper portion of the second anti-backflow water distributor (6S) is provided with a tubing (2S).
2. The anti-reflux containment injection string structure of claim 1, wherein, The plug (1), the normally open sliding sleeve (3), the pressure compensator (4), the normally closed sliding sleeve (5), the first anti-backflow water distributor (6), the packer (7) and the second anti-backflow water distributor (6S) are arranged in a casing (8).
3. The anti-reflux containment injection string structure of claim 1, wherein, The first anti-backflow water distributor (6) is arranged at a lower water injection layer (L1), and the second anti-backflow water distributor (6S) is arranged at an upper water injection layer (L2).
4. The anti-reflux containment injection string structure of claim 1, wherein, The tubing (2S) is connected to a wellhead.