Integrated hydraulic setting tool for cement retainer

Abstract

The utility model relates to the field of oil and gas well repair, in particular to an integrated hydraulic setting tool for a cement retainer. Comprising an upper connector, a setting mechanism, a piston locking mechanism, a setting ball seat mechanism and a pipe inserting mechanism. Compared with an existing setting tool, the setting tool is simple in structure and convenient to assemble and maintain; setting, releasing, back inserting and squeezing and blocking construction of the cement retainer can be completed through one pipe column, the construction time efficiency can be improved, and cost is saved; compared with rotary lifting setting of a mechanical cement retaining device, the hydraulic setting device has the advantages that the risk of setting in the middle of the cement retaining device can be effectively avoided; the utility model can be used for a vertical well, a highly-deviated well and a horizontal well, especially for the highly-deviated well and the horizontal well.

Description

Technical Field

[0001] This utility model relates to the field of oil and gas well workover, and in particular to an integrated hydraulic setting tool for cement retainers. Background Technology

[0002] As oil and gas field development enters its mid-to-late stages, some old or abandoned wells that have lost their exploitability need to be plugged. Cement retainers are commonly used for plugging, and existing cement retainers are mainly of two types: mechanical and hydraulic. Mechanical cement retainers are suitable for vertical wells or wells with a small inclination (less than 45°), while hydraulic cement retainers are suitable for vertical, deviated, and horizontal wells.

[0003] Mechanical cement retainers can complete the setting and cementing process in a single well run by lifting, lowering, and rotating the tubing string. In highly deviated or horizontal wells, due to the high frictional resistance between the tubing string and the casing wall, the surface cannot effectively transmit the torque and lifting force to the cement retainer downhole, thus failing to guarantee proper setting of the cement retainer.

[0004] Hydraulic cement retainers are hydraulically set, and there are currently two types: two-run tubing and one-run tubing. Two-run tubing requires two separate well runs to complete the setting and plugging operations, resulting in a long construction period and high costs. According to relevant literature, there are two main types of hydraulic cement retainers with one-run tubing. Patent CN214384140U, "A Hydraulic Cement Retainer," discloses a type where the channel is automatically closed by a check valve after plugging, which carries the risk of the check valve not closing tightly and the plugging agent flowing back up. Patent CN107387018A, "A Tool for Completing Setting and Cement Extrusion of a Cement Retainer in One-Run Tubing," discloses a cement retainer setting tool where, after the cement retainer is set and released, the setting piston mechanism continues to descend, breaking the shear pin of the piston chamber unlocking mechanism. The piston chamber unlocking mechanism then moves upward, driving the setting piston mechanism upward and ultimately covering the setting liquid pressure transmission hole, rendering the piston ineffective in the subsequent plugging process. The setting piston has a complex structure, making assembly and maintenance difficult. The cement holder setting tool disclosed in patent CN209212190U, "Setting Tool for Cement Retainer", requires rotation and release after the cement holder is set. The piston stroke has no control mechanism, and the central tube moves upward to close the cement holder channel during the back insertion and squeezing process. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide an integrated hydraulic setting tool for cement retainers. This invention allows for the setting, release, re-insertion, and plugging of cement retainers in a single tubing run, and can be used in vertical wells, highly deviated wells, and horizontal wells. This invention features a simple structure and is easy to assemble and maintain.

[0006] To achieve the above objectives, the technical solution provided by this utility model is as follows:

[0007] An integrated hydraulic setting tool for a cement retainer includes an upper connector, a setting mechanism, a piston locking mechanism, a setting ball seat mechanism, and a tube insertion mechanism. The setting mechanism includes an upper central tube, a lower central tube, a piston sleeve, and a propulsion sleeve connected to the upper connector. The piston sleeve and propulsion sleeve are fitted outside the upper and lower central tubes, respectively. A piston sliding seal is provided between the piston sleeve and the lower central tube. The lower end face of the piston is close to the upper end face of the propulsion sleeve. The piston can move on the lower central tube, which has a liquid inlet at its upper end. The tube insertion mechanism includes a double-seal insertion connector, a sealing ring assembly, an eighth sealing ring, and a displacement connector. The sealing ring assembly is located on the lower outer wall of the double-seal insertion connector, with its lower end face close to the upper end face of the displacement connector. The eighth sealing ring is located between the outer wall of the double-seal insertion connector and the inner wall of the sealing ring assembly. The lower end of the double-seal insertion joint is connected to the displacement joint via threads. The inner side of the lower end of the lower central tube is connected to the double-seal insertion joint via threads, and the outer side of the lower end of the lower central tube is connected to the break-off ring via threads. The break-off ring is connected to the central tube of the cement retainer via threads. The displacement joint has an annular groove on its outer wall in the middle, two straight slots penetrating the body in the middle, and a reducing stop at the bottom. The annular groove can open and close the cement-squeezing sleeve of the cement retainer, the straight slots can connect the pipe column and the squeezing and blocking channel at the bottom of the cement retainer, and the reducing stop can receive the setting ball after pressure testing. The setting ball seat mechanism includes a ball seat, a ball-dropping shear pin, and a setting ball. The ball seat is located inside the upper part of the displacement joint and close to the lower end face of the double-seal insertion joint. The setting ball is located on the upper part of the ball seat, and the ball seat is connected and fixed to the displacement joint via the ball-dropping shear pin.

[0008] Specifically, the piston locking mechanism includes an inner locking ring, an outer locking ring, an inner locking ring sleeve, a limiting sleeve, a positioning cap, and a starting shear pin. The inner and outer walls of the inner locking ring are respectively provided with upwardly inclined teeth. The inner wall of the piston sleeve is provided with teeth that match the teeth on the outer wall of the outer locking ring and are inclined downwards. The lower end of the outer wall of the upper central tube is provided with teeth that match the teeth on the inner wall of the inner locking ring and are inclined downwards. The positioning cap is connected to the inner locking ring sleeve by threads. The inner stepped surface of the positioning cap is close to the upper end face of the inner locking ring sleeve, and the upper end face of the positioning cap is close to the lower end face of the limiting sleeve. The inner wall of the inner locking ring sleeve is provided with teeth that match the teeth on the outer wall of the inner locking ring and are inclined downwards.

[0009] Specifically, a limiting step is provided on the outer side of the lower end of the upper central tube.

[0010] Specifically, the lower end of the upper central tube is fixedly connected to the upper end of the lower central tube, and the lower end of the upper central tube is sealed to the upper end of the lower central tube by a fifth sealing ring. The lower end of the upper central tube and the upper end of the lower central tube are positioned by a conical head stabilizing pin, and the upper connector is positioned to the upper central tube by a flat head stabilizing pin. A fourth sealing ring is provided between the upper connector and the upper central tube.

[0011] Specifically, the piston is slidably and sealingly connected to the piston sleeve and the lower central tube through the first sealing ring and the sixth sealing ring.

[0012] Specifically, a second sealing ring is provided between the double-sealed insertion joint and the displacement joint, and the lower end of the lower central tube is sealed to the upper end of the double-sealed insertion joint through a seventh sealing ring.

[0013] Specifically, the ball seat has a smooth slope at a 30° angle to the horizontal at the contact point with the seated ball, and the outer wall of the ball seat has a sealing ring groove and a shear pin hole. The ball seat and the displacement joint are sealed and connected by a third sealing ring, and the ball-dropping shear pin is inserted into the shear pin hole.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0015] Compared with existing setting tools, this utility model has a simple structure and is easy to assemble and maintain. This utility model can complete the setting, release, re-insertion, and plugging of the cement retainer in one trip of the tubing string, which can improve construction efficiency and save costs. This utility model has hydraulic setting, which can effectively avoid the risk of the cement retainer setting midway compared with mechanical cement retainer rotation and lifting setting. This utility model can be used in vertical wells, highly deviated wells, and horizontal wells, especially highly deviated wells and horizontal wells. Attached Figure Description

[0016] Figure 1 This is a half-sectional view of the present invention.

[0017] Figure 2 for Figure 1 A magnified view of region A in the middle.

[0018] Figure 3 for Figure 1 Enlarged view of region B in the middle;

[0019] Figure 4 This is a schematic diagram of the connection between the present invention and the cement retainer.

[0020] The component names in the attached diagram are as follows: 1-Upper connector, 2-Flat-head stabilizing pin, 3-Starting shear pin, 4-Limit sleeve, 5-Positioning cap, 6-Outer locking ring, 7-Inner locking ring sleeve, 8-Piston sleeve, 9-Limiting step, 10-Conical stabilizing pin, 11-First sealing ring, 12-Piston, 13-Propulsion sleeve, 14-Break-off ring, 15-Double-seal insertion connector, 16-Sealing ring assembly, 17-Second sealing ring, 18-Third sealing ring, 19-Ball-dropping shear pin, 20-Straight groove, 21-Shifting connector, 22-Fourth sealing ring, 23-Inner locking ring, 24-Upper central tube, 25-Fifth sealing ring, 26-Liquid inlet hole, 27-Sixth sealing ring, 28-Lower central tube, 29-Seventh sealing ring, 30-Eighth sealing ring, 31-Setting ball, 32-Ball seat, 33-Annular groove, 34-Reducing stop, 35-Cement retainer. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0022] Reference Figures 1-4 As shown, an integrated hydraulic setting tool for a cement holder includes an upper connector 1, a setting mechanism, a piston locking mechanism, a setting ball seat mechanism, a tube insertion mechanism, and a pull-off ring, etc.

[0023] The setting mechanism includes an upper central tube 24, a lower central tube 28, a piston sleeve 8, and a pusher sleeve 13, all connected to the upper connector 1. The lower end of the upper central tube 24 is fixedly connected to the upper end of the lower central tube 28, and the two ends are sealed together by a fifth sealing ring 25. The lower end of the upper central tube 24 and the upper end of the lower central tube 28 are positioned by a conical stabilizing pin 10.

[0024] The upper connector 1 is positioned to the upper central tube 24 via a flat-head stabilizing pin 2. The piston sleeve 8 and the push sleeve 13 are fitted onto the outside of the upper central tube 24 and the lower central tube 28. The piston 12 is slidably sealed between the piston sleeve 8 and the lower central tube 28. The piston 12 is slidably sealed to the piston sleeve 8 and the lower central tube 28 via a first sealing ring 11 and a sixth sealing ring 27. The lower end face of the piston 12 is close to the upper end face of the push sleeve 13. The piston 12 can move on the lower central tube 28. The upper end of the lower central tube 28 is provided with a liquid inlet hole 26. When the cement retainer 35 is set, liquid enters the gap between the upper end face of the piston 12 and the lower end face of the upper central tube 24 through the liquid inlet hole 26, and under the action of liquid pressure, pushes the piston 12 to move downward.

[0025] A fourth sealing ring 22 is provided between the upper connector 1 and the upper central tube 24.

[0026] The insertion mechanism includes a double-sealed insertion connector 15, a sealing ring assembly 16, an eighth sealing ring 30, and a displacement connector 21. The sealing ring assembly 16 is disposed on the lower outer wall of the double-sealed insertion connector 15, and the lower end face of the sealing ring assembly 16 is close to the upper end face of the displacement connector 21. The eighth sealing ring 30 is disposed between the outer wall of the double-sealed insertion connector 15 and the inner wall of the sealing ring assembly 16. The lower end of the double-sealed insertion connector 15 is connected to the displacement connector 21 by a thread. A second sealing ring 17 is provided between the double-sealed insertion connector 15 and the displacement connector 21.

[0027] The lower end of the lower center tube 28 is connected to the double-seal insertion joint 15 by a thread, and the lower end of the lower center tube 28 is connected to the upper end of the double-seal insertion joint 15 by a seventh sealing ring 29.

[0028] The lower outer end of the lower central tube 28 is threadedly connected to the pull-off ring 14. The pull-off ring 14 is threadedly connected to the central tube of the cement retainer 35. Other existing connection structures can also be used to connect the pull-off ring 14 and the central tube of the cement retainer 35.

[0029] The displacement joint 21 has an annular groove 33 on its outer wall, two straight slots 20 penetrating the main body in the middle, and a variable diameter stop 34 at the bottom. The annular groove 33 is used to open and close the cement sleeve of the cement retainer 35, the straight slots 20 are used to connect the pipe column and the bottom of the cement retainer 35 to the plugging channel, and the variable diameter stop 34 is used to receive the set-sealing ball 32 after pressure.

[0030] The setting ball seat mechanism includes a ball seat 32, a ball-dropping shear pin 19, a third sealing ring 18, and a setting ball 31. The ball seat 32 is located inside the upper part of the displacement joint 21 and close to the lower end face of the double-sealed insertion joint 15. The outer wall of the ball seat 32 is provided with a sealing ring groove and a shear pin hole. The setting ball 31 is located at the upper end of the ball seat. The contact point between the ball seat 32 and the setting ball 31 is provided with a smooth slope at a 30° angle to the horizontal direction. The ball seat 32 is connected and fixed to the displacement joint 21 by the ball-dropping shear pin 19. After the pull-off ring 14 breaks, pressure continues to be applied inside the tubing, shearing the ball-dropping shear pin 19, and the setting ball 32 falls into the lower diameter reducing stop 34 of the displacement joint 21.

[0031] The piston locking mechanism includes an inner locking ring 23, an outer locking ring 6, an inner locking ring sleeve 7, a limiting sleeve 4, a positioning cap 5, and a starting shear pin 3, etc.

[0032] The piston locking mechanism structure is not limited, as long as it meets the functional requirements of this utility model. For ease of processing and application, the following is a preferred improved solution: The inner and outer walls of the inner locking ring 23 are respectively provided with upwardly inclined teeth. The inner wall of the piston sleeve 8 is provided with downwardly inclined teeth that match the teeth on the outer wall of the outer locking ring 6. The lower outer wall of the upper central tube 24 is provided with downwardly inclined teeth that match the teeth on the inner wall of the inner locking ring 23. The positioning cap 5 is connected to the inner locking ring sleeve 7 by threads. The inner stepped surface of the positioning cap 5 is close to the upper end face of the inner locking ring sleeve 7, and the upper end face of the positioning cap 5 is close to the lower end face of the limiting sleeve 4. The inner wall of the inner locking ring sleeve 7 is provided with downwardly inclined teeth that match the teeth on the outer wall of the inner locking ring 23.

[0033] During the setting process, the piston locking mechanism moves downward with the setting mechanism and eventually comes into close contact with the limiting step 9 on the outer side of the lower end of the upper central tube 24. At this time, the inner locking ring 23 is locked, and the piston locking mechanism can no longer move upward relative to the upper central tube 24.

[0034] See Figure 1 This utility model can implement integrated plugging construction using the above technical solution. First, insert the setting tool tube insertion mechanism into the central tube of the cement retainer 35. When the sealing ring assembly 16 encounters obstruction in the central tube of the cement retainer 35, the tail of the cement retainer 35 can be tapped with a copper rod. When the upper thread of the central tube of the cement retainer 35 contacts the pull-off ring 14, clamp the upper connector 1 and rotate the tail of the cement retainer 35 so that the pull-off ring 14 and the central tube of the cement retainer 35 are connected by threads until the threads are fully threaded. At this time, the cement squeezing sleeve of the cement retainer 35 is opened by the displacement connector 21.

[0035] Next, the cement retainer 35 is set. When the entire tool is lowered to the predetermined layer, after reverse circulation well washing, the setting ball 31 is inserted, the surface high-pressure manifold is connected, and pressure is applied in stages. First, the starting shear pin 3 is cut off, and then the pull-off ring 14 is pulled off, completing the setting of the cement retainer 35. At this point, the setting tool is disengaged from the cement retainer 35, the tubing string is lifted 1-2 meters, and the cement squeezing sleeve of the cement retainer 35 closes. Simultaneously, the piston 12 and the piston locking mechanism continue to move downwards (the moving distance is the remaining stroke of the piston 12) until the lower end face of the inner locking ring sleeve 7 is pressed against the limiting step 9 on the outer side of the lower end of the upper central tube 24.

[0036] Next, the setting ball 31 is knocked down. Pressure is continued to be applied to the tubing until the set pressure is reached. Then, the ball-dropping shear pin 19 is cut off, and the setting ball 32 lands at the bottom reducing stop 34 of the shift joint 21. At this point, the setting tool is connected internally and externally.

[0037] This causes the insertion mechanism to re-insert. The tubing string is pressed down onto the cement retainer 35, and the break ring 36 overlaps at the break point. The piston 12 moves upward under the weight of the tubing string, and the amount of movement of the piston 12 is the remaining stroke of the piston 12. As mentioned above, due to the action of the inner locking ring 23, the piston locking mechanism no longer moves upward. At this time, the piston 12 returns to the position at the end of the setting. When the tubing string is pressurized again, due to the action of the outer locking ring 6, the piston 12 no longer moves downward. At the same time as the tubing string is pressed down onto the cement retainer 35, the shifting joint 21 opens the cement squeezing sleeve of the cement retainer 35, and the cement squeezing operation can be performed at this time.

[0038] After the plugging is completed, lift the tubing string 1-3 meters, close the cement-squeezing sleeve on the cement retainer 35 with the shifting joint 21, flush the entire tubing string, and backwash the excess cement slurry out of the wellbore.

[0039] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An integrated hydraulic setting tool for a cement holder, comprising an upper connector (1), a setting mechanism, a piston locking mechanism, a setting ball seat mechanism, and a tube insertion mechanism, characterized in that, The sealing mechanism includes an upper central tube (24), a lower central tube (28), a piston sleeve (8), and a pusher sleeve (13) connected to the upper connector (1). The piston sleeve (8) and the pusher sleeve (13) are sleeved on the outside of the upper central tube (24) and the lower central tube (28). The piston (12) is slidably sealed between the piston sleeve (8) and the lower central tube (28). The lower end face of the piston (12) is close to the upper end face of the pusher sleeve (13). The piston (12) can be positioned in the lower central tube (14)... 28) The upper part of the lower central tube (28) is provided with an inlet hole (26); the insertion mechanism includes a double-sealed insertion joint (15), a sealing ring assembly (16), an eighth sealing ring (30) and a shifting joint (21). The sealing ring assembly (16) is disposed on the lower outer wall of the double-sealed insertion joint (15), and the lower end face of the sealing ring assembly (16) is close to the upper end face of the shifting joint (21). The eighth sealing ring (30) is disposed on the outer wall of the double-sealed insertion joint (15). Between the inner wall of the sealing ring assembly (16) and the inner wall of the double-seal insertion joint (15), the lower end of the double-seal insertion joint (15) is connected to the displacement joint (21) by a thread. The inner side of the lower end of the lower central tube (28) is connected to the double-seal insertion joint (15) by a thread. The outer side of the lower end of the lower central tube (28) is connected to the pull-off ring (14) by a thread. The pull-off ring (14) is connected to the central tube of the cement retainer (35) by a thread. The outer wall of the middle part of the displacement joint (21) is provided with an annular groove (3). 3) Two straight slots (20) are provided in the middle that penetrate the body, and a variable diameter stop (34) is provided at the bottom; the setting ball seat mechanism includes a ball seat (32), a ball dropping shear (19) and a setting ball (31). The ball seat (32) is set inside the upper end of the displacement joint (21) and close to the lower end face of the double sealing insertion joint (15). The setting ball (31) is set on the upper end of the ball seat (32). The ball seat (32) is connected and fixed to the displacement joint (21) through the ball dropping shear (19).

2. The integrated hydraulic setting tool for a cement retainer according to claim 1, characterized in that, The piston locking mechanism includes an inner locking ring (23), an outer locking ring (6), an inner locking ring sleeve (7), a limiting sleeve (4), a positioning cap (5), and a starting shear pin (3). The inner and outer walls of the inner locking ring (23) are respectively provided with upwardly inclined teeth. The inner wall of the piston sleeve (8) is provided with teeth that match the teeth on the outer wall of the outer locking ring (6) and are inclined downwards. The lower outer wall of the upper central tube (24) is provided with teeth that match the teeth on the inner wall of the inner locking ring (23) and are inclined downwards. The positioning cap (5) is connected to the inner locking ring sleeve (7) by threads. The inner stepped surface of the positioning cap (5) is close to the upper end face of the inner locking ring sleeve (7). The upper end face of the positioning cap (5) is close to the lower end face of the limiting sleeve (4). The inner wall of the inner locking ring sleeve (7) is provided with teeth that match the teeth on the outer wall of the inner locking ring (23) and are inclined downwards.

3. The integrated hydraulic setting tool for a cement retainer according to claim 2, characterized in that, A limiting step (9) is provided on the outer side of the lower end of the upper central tube (24).

4. The integrated hydraulic setting tool for a cement retainer according to claim 1, characterized in that, The lower end of the upper central tube (24) is fixedly connected to the upper end of the lower central tube (28). The lower end of the upper central tube (24) and the upper end of the lower central tube (28) are sealed together by a fifth sealing ring (25). The lower end of the upper central tube (24) and the upper end of the lower central tube (28) are positioned by a conical head stabilizing pin (10). The upper connector (1) and the upper central tube (24) are positioned by a flat head stabilizing pin (2). A fourth sealing ring (22) is provided between the upper connector (1) and the upper central tube (24).

5. The integrated hydraulic setting tool for a cement retainer according to claim 1, characterized in that, The piston (12) is slidably sealed to the piston sleeve (8) and the lower central tube (28) through the first sealing ring (11) and the sixth sealing ring (27).

6. The integrated hydraulic setting tool for a cement retainer according to claim 1, characterized in that, A second sealing ring (17) is provided between the double-sealed insertion joint (15) and the displacement joint (21), and the lower end of the lower central tube (28) is sealed to the upper end of the double-sealed insertion joint (15) through a seventh sealing ring (29).

7. The integrated hydraulic setting tool for a cement retainer according to claim 1, characterized in that, The ball seat (32) has a smooth slope at 30° to the horizontal at the contact point with the seat ball (31). The outer wall of the ball seat (32) has a sealing ring groove and a shear pin hole. The ball seat (32) and the displacement joint (21) are sealed and connected by a third sealing ring (18). The ball dropping shear pin (19) is inserted into the shear pin hole.

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