Negative pressure jet flow sand washing and bailing device

Abstract

The utility model provides a negative pressure jet flow sand washing and bailing device which mainly comprises a double-wall drill rod, a sand bailing barrel body, a jet flow pump body and a sand disturbing connector, when fluid passes through a packer, the fluid enters a double-wall drill rod annular hole and then passes through a sand bailing barrel annular hole and a jet flow pump annular hole, when the fluid enters a high pressure cavity, most of the fluid flows through a negative pressure jet flow nozzle to be jetted upwards at a high speed, and the sand disturbing connector is connected with the sand bailing barrel body. A vacuum low-pressure area is formed; the other small part of fluid flows through a sand disturbing rotational flow opening and a sand disturbing nozzle and impacts and disturbs a well bottom sand bed, well bottom sand mixing fluid flows into a throat pipe under the action of negative pressure suction and is mixed with the fluid, sand grains are deposited to the sand bailing barrel under the rotational flow centrifugal force and gravity action of a rotational flow opening of the sand bailing barrel, and the fluid returns to the ground through a drill rod; the sand washing and bailing process not only can assist in disturbing sand grains, but also has a suction effect, and is high in sand washing and bailing efficiency.

Description

Technical Field

[0001] The utility model relates to the technical field of oil field and oil well repair, in particular to a negative pressure jet sand flushing and bailing device. Background Art

[0002] Sand production is unavoidable during oil and gas field development. Despite numerous sand control measures, sand production still persists to varying degrees in actual production. Sand production in oil wells can erode and damage pipelines and surface equipment, significantly complicating process implementation and maintenance. More importantly, sand production increases fluid flow resistance, impacting reservoir recovery and reducing well production. Therefore, sand removal is essential.

[0003] Hydraulic sand flushing and mechanical sand bailing are common methods for restoring and maintaining the production of sand-producing wells. Compared with mechanical sand bailing, hydraulic sand flushing has the advantages of relative stability, thorough bottomhole cleaning, strong continuity, and large sand flushing capacity. However, for sand flushing of leaking wells in low-pressure and leaky reservoirs, conventional hydraulic sand flushing technology is difficult to successfully apply. On the one hand, conventional hydraulic sand flushing is difficult to establish circulation in low-pressure leaking wells, and when the power fluid impacts the bottomhole sand bed, the bottomhole pressure is often greater than the formation pressure, causing a large amount of sand mixing fluid to leak into the oil-producing layer, contaminating the formation and easily reducing the oil well production. On the other hand, because the axis of the sand flushing operation string does not coincide with the axis of the wellbore, the sand mixing fluid flows in the eccentric annulus, which easily accumulates sand at the bottom of the well again, resulting in sand sticking.

[0004] Current sand bailing methods for low-pressure wells prone to leakage include the new GS negative-pressure sand bailing process, which features a fully integrated blowout preventer (BOP) in the annulus and a dedicated sand bailing check valve in the drill string. During the sand bailing process, the kelly is equipped with upper and lower cocks to maintain a slightly positive bottomhole pressure, slightly exceeding formation pressure, and manageable wellbore pressure fluctuations. The air distributor and downhole safety valve are integrated into one, providing full-wellbore kill capability. The sand bailing operation is closed and environmentally friendly. Using existing equipment, single-joint connection time can be reduced by more than half.

[0005] Although the above method is feasible, the negative pressure suction at the bottom of the well may be insufficient, and components such as special sand bailing check valves, special air distributors and downhole safety valves need to be manufactured separately, which is costly. Utility Model Content

[0006] In response to the above-mentioned deficiencies in the prior art, the present invention provides a negative pressure jet sand bailing device, the purpose of which is to solve the problems that the negative pressure suction may be insufficient, and that components such as special sand bailing check valves, special air distributors and downhole safety valves need to be manufactured separately, resulting in high costs.

[0007] In order to achieve the above-mentioned purpose of the utility model, the technical solution adopted by the utility model is: a negative pressure jet sand bailing device, including a double-wall drill pipe, a sand bailing tube body, a jet pump body, and a sand disturbing joint; the upper end of the double-wall drill pipe is provided with a packer, and the upper end of the inner wall of the double-wall drill pipe is connected to the lower end of the drill pipe; the upper end of the sand bailing tube body is connected to the lower end of the double-wall drill pipe, and the sand bailing tube body is provided with a sand bailing tube and a swirl port; the upper end of the jet pump body is connected to the lower end of the sand bailing tube body, and the jet pump body is provided with a jet pump annular hole, a suction port, a diffuser, a throat, a negative pressure chamber, and a jet nozzle; the upper end of the sand disturbing joint is connected to the lower end of the jet pump body, and the sand disturbing joint is provided with a high-pressure chamber, a sand disturbing swirl port, and a sand disturbing nozzle.

[0008] Furthermore, the double-wall drill pipe, sand bailing tube body, and jet pump body are connected by threads, the double-wall drill pipe annulus is connected with the sand bailing tube annulus, the jet pump annulus, and the high-pressure chamber, and the double-wall drill pipe inner tube is connected with the sand bailing tube and the diffuser.

[0009] Furthermore, the diffuser and the jet nozzle are of conical structure, the throat is a cylindrical channel, and the suction port is connected to the negative pressure chamber.

[0010] Furthermore, the sand bailing tube body is provided with two swirl ports, and the swirl ports are centrally symmetrical with the axis of the sand bailing tube body.

[0011] Furthermore, the sand-disturbing nozzle is parallel to the axis of the jet pump body, and the sand-disturbing nozzle is provided with two sand-disturbing swirl ports, which are centrally symmetrical with the axis.

[0012] Furthermore, the double-wall drill pipe, the sand bailing tube body, the jet pump body, and the sand disturbing joint have the same outer diameter and are connected in sequence through threads.

[0013] Furthermore, it includes a well repair pump, a winch, a traveling block, a throttle valve, a separator, and a vibrating screen installed on the ground. The well repair pump is connected to the wellhead device, a turntable is installed on the traveling block, the winch and the traveling block are connected by a wire rope, and the throttle valve, separator, and vibrating screen are connected by a return pipeline.

[0014] The beneficial effects of the utility model are:

[0015] The utility model discloses a negative pressure jet sand flushing and bailing device. The invention utilizes a ground well repair pump to pump high-pressure fluid into the annulus between the drill pipe and the wellbore. When passing through the packer, the fluid enters the annulus of the double-wall drill pipe, and then passes through the annulus of the sand bailing tube and the annulus of the jet pump. When entering the high-pressure chamber, most of the fluid flows through the negative pressure jet nozzle and is sprayed upward at high speed to form a vacuum low-pressure area; another small part of the fluid flows through the sand-disturbing vortex port and the sand-disturbing nozzle to impact and disturb the sand bed at the bottom of the well; the sand mixing liquid at the bottom of the well flows into the throat pipe under the action of negative pressure suction, and after mixing with the fluid, the sand particles are deposited in the sand bailing tube under the action of the vortex centrifugal force and gravity at the vortex port of the sand bailing tube, and the fluid returns to the ground through the drill pipe. The sand flushing and bailing process has both auxiliary disturbance of the sand particles and suction effect, and the sand flushing and bailing efficiency is high.

[0016] The utility model discloses a negative pressure jet sand flushing and bailing device. According to different low-pressure leakage reservoirs, the negative pressure jet continuous sand flushing and bailing device with reasonable parameter design is selected, which can reduce the pressure of the bottom flow field during sand flushing and bailing, reduce the leakage during the sand flushing and bailing operation and the pollution to the production layer, and can effectively solve various low-pressure leakage problems.

[0017] The utility model discloses a negative pressure jet sand flushing and bailing device. The sand flushing and bailing circulation of the invention is basically inside the drill pipe, double-wall drill pipe, sand bailing tube body and jet pump body, which solves the problems of traditional sand flushing process that it is difficult to establish circulation and the sand flushing fluid is easy to leak. It provides a new idea and solution for the sand flushing and bailing operation of low-pressure wells prone to leakage.

[0018] The utility model provides a negative pressure jet sand flushing and bailing device, which has the advantages of simple structural principle, high process reliability, strong practicability and low manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic structural diagram of a negative pressure jet sand bailing device;

[0020] Figure 2 This is a schematic diagram of the double-wall drill pipe structure of a negative pressure jet sand bailing device;

[0021] Figure 3 This is a schematic diagram of a sand bailing tube body of a negative pressure jet sand bailing device;

[0022] Figure 4 This is a schematic diagram of the structure of a sand flushing pump of a negative pressure jet sand flushing device;

[0023] Figure 5 This is a schematic diagram of the structure of a sand-disturbing joint of a negative pressure jet sand-removing device;

[0024] Figure 6 This is a schematic diagram of the three-dimensional structure of a negative pressure jet sand bailing device;

[0025] Figure 7This is a schematic diagram of the cross-sectional structure of a three-dimensional model of a negative pressure jet sand bailing device.

[0026] Reference table of accompanying symbols:

[0027] 1. Workover pump; 2. Drawworks; 3. Wire rope; 4. Traveling block; 5. Return line; 6. Rotary table; 7. Choke valve; 8. Separator; 9. Vibrating screen; 10. Drill pipe; 11. Wellhead assembly; 12. Casing; 13. Packer; 14. Double-wall drill pipe; 15. Sand bailing tube body; 16. Jet pump body; 17. Sand disturbance joint; 18. Sand bed; 19. Double-wall drill pipe outer wall; 20. Double-wall drill pipe inner wall; 21. Double-wall drill pipe inner tube; 22. Double-wall drill pipe annulus; 23. Sand bailing tube; 24. Swirl port; 25. Sand bailing tube annulus; 26. Jet pump annulus; 27. Suction port; 28. Diffuser; 29. ​​Throat; 30. Negative pressure chamber; 31. Jet nozzle; 32. High-pressure chamber; 33. Sand disturbance swirl port; 34. Sand disturbance nozzle. DETAILED DESCRIPTION

[0028] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings, wherein the same components are represented by the same reference numerals.

[0029] It should be noted that the words "front", "rear", "left", "right", "up" and "down" used in the following description refer to directions in the accompanying drawings, and the words "inside" and "outside" refer to directions toward or away from the geometric center of a specific component, respectively.

[0030] In order to make the contents of the present invention more clearly understood, 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.

[0031] like Figures 1 to 7 As shown, a negative pressure jet sand bailing device includes a double-wall drill pipe 14, a sand bailing tube body 15, a jet pump body 16, and a sand disturbing joint 17; the upper end of the double-wall drill pipe 14 is provided with a packer 13, and the upper end of the inner wall 20 of the double-wall drill pipe is connected to the lower end of the drill pipe 10; the upper end of the sand bailing tube body 15 is connected to the lower end of the double-wall drill pipe 14, and the sand bailing tube body 15 is provided with a sand bailing tube 23 and a vortex port 24; the upper end of the jet pump body 16 is connected to the lower end of the sand bailing tube body 15, and the jet pump body 16 is provided with a jet pump annular hole 26, a suction port 27, a diffuser 28, a throat 29, a negative pressure chamber 30, and a jet nozzle 31; the upper end of the sand disturbing joint 17 is connected to the lower end of the jet pump body 16, and the sand disturbing joint 17 is provided with a high-pressure chamber 32, a sand disturbing vortex port 33, and a sand disturbing nozzle 34.

[0032] The double-wall drill pipe 14, the sand bailing tube body 15, and the jet pump body 16 are connected by threads. The double-wall drill pipe annulus 22 is connected with the sand bailing tube annulus 25, the jet pump annulus 26, and the high-pressure chamber 32. The double-wall drill pipe inner tube 21 is connected with the sand bailing tube 23 and the diffuser 28.

[0033] The diffuser 28 and the jet nozzle 31 are of conical structure, the throat 29 is a cylindrical channel, and the suction port 27 is connected to the negative pressure chamber 30.

[0034] The sand bailing tube body 15 is provided with two swirl ports 24 , and the swirl ports 24 are centrally symmetrical with the axis of the sand bailing tube body 15 .

[0035] The sand-disturbing nozzle 34 is parallel to the axis of the jet pump body 16 . The sand-disturbing nozzle 34 is provided with two sand-disturbing swirl ports 33 . The sand-disturbing swirl ports 33 are centrally symmetrical with the axis.

[0036] The double-wall drill pipe 14, the sand bailing tube body 15, the jet pump body 16 and the sand disturbing joint 17 have the same outer diameter and are connected in sequence through threads.

[0037] The workover pump 1, a winch 2, a traveling block 4, a throttle valve 7, a separator 8, and a vibrating screen 9 are installed on the ground. The workover pump 1 is connected to the wellhead device 11. A turntable 6 is installed on the traveling block 4. The winch 2 and the traveling block 4 are connected by a wire rope 3. The throttle valve 7, the separator 8, and the vibrating screen 9 are connected by a return pipeline 5.

[0038] The sand bailing method in this utility model patent includes the following steps:

[0039] In actual use, first, the sand-disturbing joint 17, the jet pump body 16, the sand bailing tube body 15, the double-wall drill pipe 14, and the drill pipe 10 are connected in sequence and lowered into the well where sand bailing is required. The packer 13 is then lowered into the upper end of the double-wall drill pipe 14. The fluid is raised to high pressure by the workover pump 1 and enters the annulus between the drill pipe 10 and the casing 12 through the wellhead assembly 11. After flowing through the packer 13, the fluid enters the annulus 22 of the double-wall drill pipe and flows into the annulus 25 of the sand bailing tube, the annulus 26 of the jet pump, and the high-pressure chamber 32.

[0040] Secondly, the high-pressure fluid in the high-pressure chamber 32 flows in two directions, with most of the fluid flowing through the jet nozzle 31. When flowing through the jet nozzle 31, the fluid forms a high-speed jet due to the reduction of the flow cross-sectional area, and forms a local vacuum low-pressure area in the negative pressure chamber 30; while a small part of the fluid flows through the tangential sand-disturbing swirl port 33 and the sand-disturbing nozzle 34 to form a high-speed rotating jet, which impacts and disturbs the bottomhole sand bed 18. The bottomhole sand mixing fluid is sucked into the negative pressure suction port 27 of the jet pump body 16 under the action of vacuum suction force;

[0041] Finally, the sand mixing liquid and the high-speed fluid ejected from the jet nozzle 31 are initially mixed in the negative pressure chamber 30 and further mixed when flowing through the throat pipe 29 and diffuser 28. The mixed fluid flows through the diffuser 28 with a continuously expanding cross-sectional diameter, where its kinetic energy is converted into pressure energy and enters the swirl port 24 of the sand bailing tube body 15. The sand mixing liquid changes its flow direction from axial to tangential and rotates in the annular hole of the sand bailing tube 23. Under the action of centrifugal force and gravity, the sand particles settle into the sand bailing tube 23, and the fluid flows into the double-wall drill pipe inner tube 21 and the double-wall drill pipe 14 and returns to the surface. After returning to the surface, it is processed through the return pipeline 5, throttle valve 7, separator 8, and vibrating screen 9, completing the entire negative pressure jet sand bailing process.

[0042] The above description is only a preferred embodiment of the present utility model patent and is not intended to limit the present utility model patent. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model patent shall be included in the scope of protection of the present utility model patent.

Claims

1. A negative pressure jet sand bailing device, characterized in that: The invention comprises a double-wall drill pipe (14), a sand bailing tube body (15), a jet pump body (16), and a sand disturbing joint (17); the upper end of the double-wall drill pipe (14) is provided with a packer (13), the upper end of the inner wall (20) of the double-wall drill pipe is connected to the lower end of the drill pipe (10); the upper end of the sand bailing tube body (15) is connected to the lower end of the double-wall drill pipe (14), the sand bailing tube body (15) is provided with a sand bailing tube (23) and a swirl port (24); the jet pump body The upper end of the jet pump (16) is connected to the lower end of the sand bailing tube body (15), and the jet pump body (16) is provided with a jet pump annular hole (26), a suction port (27), a diffusion pipe (28), a throat pipe (29), a negative pressure chamber (30), and a jet nozzle (31); the upper end of the sand disturbing joint (17) is communicated with the lower end of the jet pump body (16), and the sand disturbing joint (17) is provided with a high-pressure chamber (32), a sand disturbing swirl port (33), and a sand disturbing nozzle (34).

2. A negative pressure jet sand bailing device according to claim 1, characterized in that: The double-wall drill pipe (14), the sand bailing tube body (15), and the jet pump body (16) are connected by threads; the double-wall drill pipe annular hole (22) is communicated with the sand bailing tube annular hole (25), the jet pump annular hole (26), and the high-pressure chamber (32); and the double-wall drill pipe inner tube (21) is communicated with the sand bailing tube (23) and the diffusion tube (28).

3. The negative pressure jet sand bailing device according to claim 1, characterized in that: The diffusion pipe (28) and the jet nozzle (31) are of conical structure, the throat pipe (29) is a cylindrical channel, and the suction port (27) is in communication with the negative pressure chamber (30).

4. The negative pressure jet sand bailing device according to claim 1, characterized in that: The sand bailing tube body (15) is provided with two swirl ports (24), and the swirl ports (24) are centrally symmetrical with the axis of the sand bailing tube body (15).

5. The negative pressure jet sand bailing device according to claim 1, characterized in that: The sand-disturbing nozzle (34) is parallel to the axis of the jet pump body (16). The sand-disturbing nozzle (34) is provided with two sand-disturbing swirl ports (33), and the sand-disturbing swirl ports (33) are centrally symmetrical with the axis.

6. The negative pressure jet sand bailing device according to claim 1, characterized in that: The double-wall drill pipe (14), the sand bailing tube body (15), the jet pump body (16), and the sand disturbing joint (17) have the same outer diameters and are connected in sequence through threads.

7. The negative pressure jet sand bailing device according to claim 1, characterized in that: The invention comprises a well repair pump (1), a winch (2), a traveling block (4), a throttle valve (7), a separator (8), and a vibrating screen (9) installed on the ground. The well repair pump (1) is connected to a wellhead device (11). A turntable (6) is installed on the traveling block (4). The winch (2) and the traveling block (4) are connected by a steel wire rope (3). The throttle valve (7), the separator (8), and the vibrating screen (9) are connected by a return pipeline (5).

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