Segmented control leakage finding pipe column for injection well
By designing a section-controlled leakage search column for oil field water injection wells, the existing leakage search column pressure relief points, inaccurate judgments and cumbersome operations are solved, and more efficient leakage search operations and more accurate judgments on the leakage range are achieved, which reduces production costs and improves the oil field development efficiency.
Patent Information
- Application Number
- CN202311363551.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-10-20
- Publication Date
- 2025-04-22
AI Technical Summary
The existing leak-finding column has problems such as pressure relief points, inaccurate judgments when finding leaks, and cumbersome operations.
A single-stage injection well control leakage detection pipe column is designed, through the overall pipe column downward, and the single-stage injection switch is sent step by step to observe the ground injection volume to efficiently search for leakage. The pipe string includes an oil pipe, a filling section and a packer. The injector and a packer are connected to the packer. The inside of the filling center tube is connected to the Ver seat by a shear pin. The outer part of the packer central tube is equipped with an upper rubber barrel and a lower rubber barrel for sealing and pressure conduction.
It improves the sealing and success rate of leak finding, simplifies the operation process, does not require multiple pipe strings to be lowered, significantly improves construction efficiency, reduces uncertainty in the range of leaks, reduces production costs, and improves oilfield development efficiency.
Smart Images
Figure CN119860226A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of stratified water injection of oil field injection wells, in particular to a segmented control leak finding pipe string for injection wells. Background Art
[0002] At present, the double-stage packer leak detection string commonly used in oil fields has a simple and easy-to-operate whole process. However, since there are multiple oil pipes connected to the upper part of the upper packer, there is a pressure relief point. When the leakage is small and the pressure is used to judge the leak, the judgment is inaccurate. The single-stage packer leak detection string overcomes the deficiency of the pressure relief point when the double-stage packer is used for leak detection, but the well must be set up and the oil pipe must be hung at the wellhead every time the operation is carried out. The operation is cumbersome, and it is impossible to judge whether the packer is sealed on the ground. Summary of the invention
[0003] In order to overcome the shortcomings of the existing leak finding pipe string, such as the existence of pressure relief points, inaccurate judgment during leak finding, and complicated operation, the present invention provides a segmented control leak finding pipe string for an injection well. The segmented control leak finding pipe string for an injection well has good sealing performance, a high leak finding success rate, does not require multiple trips of the pipe string, and is simple to operate.
[0004] The technical scheme of the present invention is: a segmented control leak detection pipe string for injection wells, comprising an oil pipe, a plurality of injection sections are connected to the oil pipe, two adjacent injection sections are connected by the oil pipe, the injection sections comprise an injector and a packer, in each injection section, the packer is connected to the lower end of the injector, and the bottom of the packer at the lowermost end is connected to a wire plug; The dispenser includes a lower joint of the dispenser, the upper end of which is respectively connected to the central tube of the dispenser and the sealing joint, with an annular cavity between the two. The interior of the central tube of the dispenser is connected to a valve seat via a shear pin, and a liquid hole is opened on the side wall of the central tube of the dispenser, the liquid hole corresponds to the annular cavity, and a bridge channel of the dispenser communicating with the annular cavity is opened on the lower joint of the dispenser; the inner diameter of the valve seat of the dispenser in different dispensing sections increases successively from bottom to top.
[0005] The packer comprises an upper joint and a lower joint, a center tube of the packer is connected between the two, an upper rubber tube and a lower rubber tube are arranged outside the center tube of the packer, and a flow channel corresponding to the bridge channel of the dispenser is arranged on the upper joint and the lower joint of the packer.
[0006] The dispenser also includes an upper joint of the dispenser, a central tube of the dispenser is connected between the upper joint of the dispenser and the lower joint of the dispenser, and an adjusting nut is connected to the outside of the upper joint of the dispenser; a sealing seat is arranged outside the central tube of the dispenser, and the sealing seat is located on the upper part of the sealing joint; a spring is arranged between the adjusting nut and the sealing seat.
[0007] A boss is arranged inside the lower joint of the dispenser, and the inner diameter of the boss is smaller than the outer diameter of the valve seat.
[0008] The bridge channel of the dispenser is a plurality of through holes evenly distributed along the circumferential direction.
[0009] The packer center tube in the packer includes an upper center tube and a lower center tube, which are connected via an intermediate joint. The upper rubber tube is located outside the upper center tube, and the lower rubber tube is located outside the lower center tube.
[0010] The upper and lower ends of the upper rubber tube are respectively provided with an upper rubber tube upper seat and an upper rubber tube lower seat, wherein the upper rubber tube upper seat is connected to the upper joint of the packer, and the upper rubber tube lower seat is connected to the middle joint.
[0011] The upper and lower ends of the lower rubber cylinder are respectively provided with a lower rubber cylinder upper seat and a lower rubber cylinder lower seat, wherein the lower rubber cylinder upper seat is connected to the middle joint, and the lower rubber cylinder lower seat is connected to the packer lower joint.
[0012] The present invention has the following beneficial effects: Due to the adoption of the above scheme, the segmented control leak detection pipe string of the water injection well is lowered through the whole pipe string, and the single-stage injection switch is triggered step by step, and the injection volume on the ground is observed to perform multi-point efficient leak detection. The problems of cross-flow and poor voltage stabilization effect, fuzzy judgment of leak points, and easy damage of tools that occur during the current leak detection of the pipe string are solved. During the leak detection operation, there is no need to lift and lower the pipe string many times, the construction efficiency is greatly improved, and the leakage range is more accurate, thereby reducing the pressure on the leak detection operation team, reducing production costs, and improving the benefits of oil field development. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 It is a schematic diagram of the structure of the dispenser in the present invention; Figure 3 It is a schematic diagram of the structure of the packer in the present invention, wherein the left side is the upper half and the right side is the lower half.
[0014] In the figure, 1-tubing, 2-first section injector, 3-packer, 4-first layer to be measured, 5-second section injector, 6-second layer to be measured, 7-third section injector, 8-third layer to be measured, 9-fourth section injector, 10-thread plug, 11-injector upper joint, 12-adjusting nut, 13-adjusting cap, 14-spring, 15-injector center tube, 16-sealing seat, 17-valve seat, 18-fluid hole, 19-sealing joint, 20-shear Cut pin, 21-injection dispenser lower joint, 22-injection dispenser bridge channel, 23-annular cavity, 31-packer upper joint, 32-upper joint flow channel, 33-sealing ring, 34-upper rubber tube upper seat, 35-upper center pipe, 36-upper rubber tube, 37-upper rubber tube lower seat, 38-middle joint, 39-lower rubber tube upper seat, 40-lower center pipe, 41-lower rubber tube, 42-lower rubber tube lower seat, 43-lower joint flow channel, 44-packer lower joint. Implementation
[0015] The present invention will be further described below in conjunction with the accompanying drawings: Depend on Figures 1 to 3 As shown, a segmented control leak detection string for injection wells includes an oil pipe 1, and the oil pipe 1 is connected to a plurality of injection sections, and two adjacent injection sections are connected by oil pipes, and each layer to be tested is located between two adjacent injection sections. The injection section includes an injector and a packer 3, and the packer 3 in each injection section is connected to the lower end of the injector, and the bottom of the packer 3 at the lowermost end is connected to a plug 10.
[0016] The dispenser comprises an upper joint 11 and a lower joint 21, and a central tube 15 of the dispenser is connected between the two. The upper joint 11 of the dispenser is externally connected to an adjusting nut 12, and an adjusting cap 13 is provided at the lower end of the adjusting nut 12. The upper end of the lower joint 21 of the dispenser is externally connected to a sealing joint 19, and an annular cavity 23 is formed between the sealing joint 19 and the central tube 15 of the dispenser. A sealing seat 16 is provided at the upper part of the sealing joint 19, and the sealing seat 16 is located outside the central tube 15 of the dispenser. A spring 14 is provided between the adjusting cap 13 and the sealing seat 16.
[0017] The center tube 15 of the dispenser is connected to the valve seat 17 through a shear pin 20. The upper surface of the valve seat 17 is an inclined surface. When the ball is cast, the conical surface cooperates with the steel ball. When the leak detection column is used, the inner diameters of the valve seats 17 in the dispensers of different dispensing sections are different, and the inner diameter of the valve seats gradually increases from bottom to top, that is, the inner diameters of the valve seats 17 in the fourth-section dispenser 9, the third-section dispenser 7, the second-section dispenser 5, and the first-section dispenser 2 increase in sequence. A boss is provided inside the lower joint 21 of the dispenser, and the inner diameter of the boss is smaller than the outer diameter of the valve seat 17, so that the valve seat 17 can sit on the boss when moving downward. A liquid hole 18 is formed on the side wall of the central tube 15 of the dispenser, and the liquid hole 18 corresponds to the annular cavity 23. A dispenser bridge channel 22 communicating with the annular cavity 23 is formed on the lower joint 21 of the dispenser, and the dispenser bridge channel 22 is a plurality of through holes evenly distributed along the circumferential direction. The valve seat 17 closes the liquid hole 18 under the fixation of the shear pin 20. When the shear pin 20 cuts off the valve seat 17 and moves down to the boss of the lower joint 21 of the dispenser, the liquid hole 18 communicates with the annular cavity 23 and the dispenser bridge channel 22.
[0018] The packer 3 includes a packer upper joint 31 and a packer lower joint 44. The packer upper joint 31 is provided with an upper joint flow passage 32 corresponding to the injector bridge passage 22, and the packer lower joint 44 is provided with a lower joint flow passage 44 corresponding to the injector bridge passage 22. A packer center pipe is connected between the packer upper joint 31 and the packer lower joint 44. The packer center pipe includes an upper center pipe 35 and a lower center pipe 40, which are connected via an intermediate joint 38. An upper rubber tube 36 is provided outside the upper center pipe 35. An upper rubber tube upper seat 34 and an upper rubber tube lower seat 37 are provided at the upper and lower ends of the upper rubber tube 36, respectively. The upper rubber tube upper seat 34 is connected to the outside of the packer upper joint 31, and the upper rubber tube lower seat 37 is connected to the intermediate joint 38. A lower rubber tube 41 is provided outside the lower center pipe 40, and a lower rubber tube upper seat 39 and a lower rubber tube lower seat 42 are provided at the upper and lower ends of the lower rubber tube 41, wherein the lower rubber tube upper seat 39 is connected to the middle joint 38, and the lower rubber tube lower seat 42 is connected to the outside of the packer lower joint 44. A sealing ring 32 is provided between the packer upper joint 31 and the upper center pipe 35, and between the packer upper joint 31 and the upper rubber tube upper seat 34. Similarly, a sealing ring is also provided between the packer lower joint 44 and the lower center pipe 40, and between the packer lower joint 44 and the lower rubber tube lower seat 42.
[0019] When the leak detection string is working, a maximum of 5 groups of injection sections can be used in one trip of the string. Figure 1 The figure shows three layers to be tested, so there are 4 groups of injection sections. After the pipe string is lowered into the well, since the bottom of the fourth section of the injector is provided with a thread plug 10, there is no need to drop a ball to plug it. First, pressurize to test whether the casing at the third layer 8 to be tested has leakage, and then put in a steel ball with the smallest diameter. The steel ball falls on the third section of the injector 7, and the steel ball seals the valve seat 17 and blocks the central channel of the injector. As the injection pressure increases, the shear pin 10 is cut off, and the valve seat 17 falls downward on the lower joint 21 of the injector, and the liquid hole 18 is exposed. The sealing seat 16 compresses the spring 14 upward under pressure, detaches from the sealing joint 19, and forms an oil-casing connection. At the same time, high-pressure water passes through the bridge channel 22 of the injector and the flow channel 32 of the upper joint of the packer, compresses the upper rubber cylinder 36 to expand, and blocks the inner wall of the casing. At the same time, the lower liquid pressure compresses the lower rubber cylinder 41 through the flow channel 43 of the lower joint, so that the third layer 6 to be tested is sealed both above and below. The higher the pressure, the better the sealing effect.
[0020] After the packer is set, steel balls are delivered step by step to seal the second-stage injector 5 and the first-stage injector 2 in turn. The injector injects water into the annular space of the casing, and the surface injection volume is observed in sections to determine whether there are leaks in the second layer to be tested 6 and the first layer to be tested 4 in turn.
[0021] When the injection stops, the injector pushes the sealing seat 16 downward to seal the sealing joint 19 under the elastic force of the spring 14, closing the oil casing connection. At the same time, the rubber tube in the packer is affected by its own elastic force and returns to the state when it was lowered into the well, realizing unsealing.
Claims
1. A segmented control leak detection string for an injection well, comprising an oil pipe (1), characterized in that: The oil pipe (1) is connected to a plurality of injection sections, and two adjacent injection sections are connected via the oil pipe. The injection sections include an injector and a packer (3). In each injection section, the packer (3) is connected to the lower end of the injector, and the bottom of the packer (3) at the lowermost end is connected to a threaded plug (10); The dispenser comprises a dispenser lower joint (21), the upper end of which is respectively connected to a dispenser center tube (15) and a sealing joint (19), with an annular cavity (23) therebetween; the interior of the dispenser center tube (15) is connected to a valve seat (17) via a shear pin (20); a liquid hole (18) is formed on a side wall of the dispenser center tube (15), the liquid hole (18) corresponding to the annular cavity (23); and a dispenser bridge channel (22) communicating with the annular cavity (23) is formed on the dispenser lower joint (21); and the inner diameter of the valve seat (17) of the dispenser in different dispensing sections increases from bottom to top.
2. The injection well segmented control leak detection string according to claim 1, characterized in that: The packer (3) comprises an upper packer joint (31) and a lower packer joint (44), a packer center tube being connected between the two, an upper rubber tube (36) and a lower rubber tube (41) being arranged outside the packer center tube, and a flow passage corresponding to the injector bridge passage (22) is arranged on the upper packer joint (31) and the lower packer joint (44).
3. The segmented control leak detection string for injection wells according to claim 1, characterized in that: The dispenser further comprises an upper joint (11) of the dispenser, a central tube (15) of the dispenser connected between the upper joint (11) of the dispenser and a lower joint (21) of the dispenser, and an adjusting nut (12) is externally connected to the upper joint (11) of the dispenser; a sealing seat (16) is externally provided on the central tube (15) of the dispenser, and the sealing seat (16) is located on the upper part of the sealing joint (19); and a spring (4) is provided between the adjusting nut (12) and the sealing seat (16).
4. The segmented control leak detection string for injection wells according to claim 3 is characterized in that: A boss is provided inside the lower joint (21) of the dispenser, and the inner diameter of the boss is smaller than the outer diameter of the valve seat (17).
5. The segmented control leak detection string for injection wells according to claim 4 is characterized in that: The dispenser bridge channel (22) is a plurality of through holes evenly distributed along the circumferential direction.
6. The segmented control leak detection string for injection wells according to claim 2, characterized in that: The packer center pipe in the packer (3) comprises an upper center pipe (35) and a lower center pipe (40), which are connected via an intermediate joint (38), the upper rubber tube (36) is located outside the upper center pipe (35), and the lower rubber tube (41) is located outside the lower center pipe (40).
7. The segmented control leak detection string for injection wells according to claim 6 is characterized in that: The upper and lower ends of the upper rubber cylinder (36) are respectively provided with an upper rubber cylinder upper seat (34) and an upper rubber cylinder lower seat (37), wherein the upper rubber cylinder upper seat (34) is connected to the packer upper joint (31), and the upper rubber cylinder lower seat (37) is connected to the middle joint (38).
8. The segmented control leak detection string for injection wells according to claim 7, characterized in that: The lower rubber cylinder (41) is provided with a lower rubber cylinder upper seat (39) and a lower rubber cylinder lower seat (42) at the upper and lower ends thereof, respectively, wherein the lower rubber cylinder upper seat (39) is connected to the middle joint (38), and the lower rubber cylinder lower seat (42) is connected to the packer lower joint (44).