Leakage plugging and oil production device for multi-point water-outlet oil well and leak plugging and oil production method

Abstract

The present invention discloses a plugging and oil production device for a multi-point water-producing oil well and a plugging and oil production method, comprising a seating and squeezing integrated tool and a drillable pipe-inserted oil production bridge plug, a seating ring is provided below the step of the upper end convex ring of the seating and squeezing bridge plug core shaft, and a seating mechanism is provided between the seating ring and the guide head; a seating and squeezing push tube is sleeved on the outer periphery of the core shaft convex ring and abuts against the upper part of the seating and squeezing push tube, and the upper end of the seating and squeezing push tube is screwed to the outer periphery of the lower liquid cylinder piston; a tension ring is screwed into the internal thread of the core shaft convex ring, and the upper end of the tension ring is connected to the seating and squeezing lower core shaft, and the upper outer wall of the seating and squeezing lower core shaft is sealed with the inner wall of the lower liquid cylinder piston. The oil production method comprises the following steps in sequence: determining that a leaking section appears above the casing cementing section and a water-producing layer appears in the casing cementing section; completing the plugging of the leaking section above the casing cementing section; completing the plugging of the water-producing layer of the casing cementing section; carrying out oil production in the adjacent oil layer below the water-producing layer; and continuing to carry out oil production in the next oil layer. The present invention can reduce the number of times of pulling in and out the pipe string and save the operation cycle.

Description

Technical Field

[0001] The invention relates to a plugging tool for a casing damaged well in an oil field, in particular to a plugging and oil production device for a multi-point water-outlet oil well; the invention also relates to a plugging and oil production method for a multi-point water-outlet oil well, belonging to the technical field of plugging and oil production in oil and water wells. Background Art

[0002] With the continuous deepening of oilfield development, the extension of oil well production life, as well as the corrosion and scaling problems caused by differential fluid extraction and high water content, the number of casing damaged wells and casing leaking wells has continued to increase. Complex wellbore conditions such as long leaking sections and multiple leaking sections, as well as development measures such as water jamming and return, have seriously restricted the subsequent development of old oilfields.

[0003] Conventional water-stuck oil production technology has its own limitations in long leaking sections, multi-section leaking sections, multi-layer water-stuck sections, and downward development. In particular, conventional water-stuck oil production technology in small wells cannot be implemented at all. For example, the operation cost of hanging small casing is high, the construction period is long, and the subsequent construction is difficult; the effective period of the pump-belt packer is short, and the risk of sticking the pipe column is high; the construction period of the ash squeezing plugging operation is long, the operation cost is high, the risk is high, and the plugging success rate is low.

[0004] With the soaring oil prices, it is more and more urgent to strengthen the research on the exploitation of leaky wells and complex wells, especially for oil wells with multiple formations or with a small distance between adjacent formations. The intubation oil production technology is often used. The total number of intubation oil production wells and the number of wells opened are increasing. Taking Jiangsu Oilfield as an example, the average annual number of newly added intubation oil production wells is nearly 20.

[0005] Conventional well intubation oil production process mainly consists of QSC-444 squeezed ash bridge plug, intubation and bridge plug seating tools, pump hanging pipe string, etc. In the operation of intubation oil production wells, it is often the case that the intubation is not inserted into place, sand and scale are blocked in the bridge plug, and the sealing stability of the intubation is poor.

[0006] In addition, after the successful insertion of the tube, during the oil production process, due to the peristalsis of the oil pump, the tube will move up and down in the tube insertion and production bridge plug, and the O-ring sealing between the tube and the bridge plug will be worn, resulting in the failure of the sealing of the tube insertion and production bridge plug.

[0007] When an oil well needs to be repaired or modified, a special salvage tool must be used to fish out the bridge plug. However, due to the long retention time of the bridge plug or the change of the wellbore casing, the bridge plug salvage often fails or even undergoes a major repair. In addition, the removable pipe-inserted bridge plug is not easy to grind, which seriously affects the progress of subsequent oil well measures.

[0008] During cementing, cement slurry is injected along the casing, flows out from the lower port of the casing into the annulus outside the casing, and returns to a certain height along the annulus. After solidification, cementing is completed. The casing in the cementing section is surrounded by cement on the outside, so only the inner wall is corroded. However, the casing above the return height section is not wrapped with cement on the outside, so both the inner and outer walls are corroded. After a long period of mining, it is more likely to leak. The leaking section above the return height section must be reliably plugged to avoid greater risks.

[0009] The common method of plugging is to inject ash, hit the baffle, wait for solidification, and then squeeze the ash to seal. Due to the influence of formation pressure, the wellbore often overflows or leaks, and sometimes it is difficult to successfully inject ash plugs in the specified well section. The existing plugging process of metal bridge plugs is: ⑴ Use the packer to find the leak to determine the leak location and calculate the water absorption of the leaking section; ⑵ Play a metal bridge plug below the leaking section, and pull out the bridge plug string after sealing; ⑶ Lower the sand filling string and fill sand above the metal bridge plug to protect the metal bridge plug; ⑷ According to the water absorption, inject enough cement slurry above the sand layer; ⑸ Pressurize the wellhead to squeeze the cement slurry into the leaking layer to achieve plugging; ⑹ Drill ash to the sand layer above the bridge plug, then conduct a pressure test and determine that the pressure test is qualified; ⑺ Lower the bridge plug string to salvage the metal bridge plug; ⑻ Lower the wellbore string to clear the well to the bottom of the production layer.

[0010] When salvaging a metal bridge plug, if the ash squeezing pressure in the leaking section is high, it is easy to cause the casing to deform, resulting in failure to salvage the bridge plug; or there may be a situation where the bridge plug cannot be unstuck or residual ash is stuck on the surface of the bridge plug, resulting in unsuccessful salvage.

[0011] The existing metal bridge plug setting tool has 6 10mm pressure relief holes on the outside, and the diameter of the central hole is only 20mm, which cannot be used for cement replacement and cement extrusion. After the bridge plug is set, the only way is to inject cement and squeeze cement by lowering the pipe column, which takes a long time to complete the well cycle and has high operation costs. In addition, the outer diameter of the existing metal bridge plug setting tool is 114mm, and the gap between it and the inner wall of the casing is too small. If the tool is lifted, a large pumping effect will be generated, affecting the stability of the injected cement slurry. Summary of the invention

[0012] The primary purpose of the present invention is to overcome the problems existing in the prior art and provide a plugging and oil production device for multi-point water-producing oil wells. The next trip of the tubing string can plug the leaking section above the cementing section, and after plugging the leak, it can directly enter the isolation of the water-producing layer below and the oil production layer, greatly saving the operation cycle.

[0013] In order to solve the above technical problems, a plugging and oil production device for a multi-point water-outlet oil well of the present invention comprises a seating and squeezing integrated tool for plugging leaks above a cementing section and a drillable pipe-inserted oil production bridge plug for plugging the water-outlet layer of the cementing section, the seating and squeezing integrated tool comprises a seating and squeezing bridge plug mandrel, the lower end of the seating and squeezing bridge plug mandrel is rotatably connected to a seating and squeezing guide head on the outer circumference, the upper end of the seating and squeezing bridge plug mandrel is closed and provided with a seating and squeezing bridge plug mandrel convex ring extending upwardly with a diameter expansion, a seating and sealing ring is provided below the step of the seating and squeezing bridge plug mandrel convex ring, and the seating and squeezing bridge plug mandrel is provided with a sealing ring. A seating sealing mechanism is provided between the sealing ring and the seating guide head; a seating push cylinder is sleeved on the outer periphery of the convex ring of the seating bridge plug core shaft, the lower end of the seating push cylinder abuts against the upper end surface of the seating sealing ring, and the upper end of the seating push cylinder is screwed with the outer periphery of the piston of the seating lower hydraulic cylinder; a seating tension ring is screwed into the internal thread of the convex ring of the seating bridge plug core shaft, the upper end inner wall of the seating tension ring is screwed with the seating lower core shaft, and the upper outer wall of the seating lower core shaft is sealed with the inner wall of the seating lower hydraulic cylinder piston.

[0014] As an improvement of the present invention, the upper end of the lower sitting shaft is rotatably connected to the upper sitting shaft, and the upper end of the lower sitting shaft is rotatably connected to the sitting shaft piston, the outer wall of the sitting shaft piston is sealed with the inner wall of the cylinder of the lower sitting cylinder, and the cylinder of the lower sitting cylinder is connected to the lower sitting cylinder piston as a whole; a lower hydraulic chamber is provided between the bottom of the sitting shaft piston and the top of the lower sitting cylinder piston, and the upper circumference of the lower sitting shaft is provided with a sitting shaft pressure transmission hole connected to the lower hydraulic chamber; a sealing plug is provided in the inner cavity of the lower end of the lower sitting shaft, and a plug convex ring is provided on the middle outer circumference of the sealing plug, the plug convex ring is located below the lower sitting shaft and embedded in the groove of the sitting tension ring, and the large diameter section of the lower end of the sealing plug fits in the inner cavity of the sitting tension ring.

[0015] As a further improvement of the present invention, the upper end of the sitting and squeezing lower hydraulic cylinder is screwed with a sitting and squeezing upper hydraulic cylinder piston, the inner wall of the sitting and squeezing upper hydraulic cylinder piston is sealed with the outer wall of the sitting and squeezing upper core shaft, the upper end of the sitting and squeezing upper core shaft is screwed into the lower end internal thread of the sitting and squeezing upper joint, the upper end outer periphery of the sitting and squeezing upper hydraulic cylinder piston is connected as a whole with the barrel of the sitting and squeezing upper hydraulic cylinder, the upper outer periphery of the sitting and squeezing upper hydraulic cylinder is suspended on the middle outer periphery of the sitting and squeezing upper joint by shear nails, an upper hydraulic chamber is provided between the bottom of the sitting and squeezing upper joint and the top of the sitting and squeezing upper hydraulic cylinder piston, the upper circumference of the sitting and squeezing upper core shaft is provided with a sitting and squeezing upper core shaft pressure transmission hole connected with the upper hydraulic chamber; the lower circumference of the sitting and squeezing lower hydraulic cylinder is provided with a sitting and squeezing lower hydraulic cylinder through hole connected with the upper cavity of the sitting and squeezing core shaft piston.

[0016] As a further improvement of the present invention, the outer circumference of the lower end of the insertion and production center tube of the drillable tubing production bridge plug is screwed with an insertion and production guide shoe, the upper end of the insertion and production center tube is provided with an expanded diameter insertion and production center tube convex ring, a insertion and production push ring is provided below the step of the insertion and production center tube convex ring, and an insertion and production sealing mechanism is provided between the insertion and production push ring and the insertion and production guide shoe; the outer circumference of the insertion and production center tube convex ring is sleeved with an insertion and production push cylinder, the lower end of the insertion and production push cylinder abuts against the upper end surface of the insertion and production push ring, and the upper end of the insertion and production push cylinder is screwed with the outer circumference of the insertion and production lower hydraulic cylinder; the inner thread of the insertion and production center tube convex ring A plugging and mining shear ring is screwed in the middle, and a conversion joint is screwed on the inner wall of the upper end of the plugging and mining shear ring, and a plugging and mining lower core shaft is screwed on the upper end of the conversion joint. The upper outer wall of the plugging and mining lower core shaft is sealed with the inner wall of the piston of the plugging and mining lower hydraulic cylinder, and an plugging and mining upper core shaft is screwed on the outer circumference of the upper end of the plugging and mining lower core shaft, and the lower piston outer wall of the plugging and mining upper core shaft is sealed with the plugging and mining lower hydraulic cylinder, a lower hydraulic chamber is provided between the bottom of the piston of the plugging and mining upper core shaft and the top of the piston of the plugging and mining lower hydraulic cylinder, and a plugging and mining lower core shaft pressure transmission hole is provided on the upper circumference of the plugging and mining lower core shaft, which is connected with the lower hydraulic chamber.

[0017] As a further improvement of the present invention, the upper end of the lower hydraulic cylinder is screwed with the upper hydraulic cylinder, the inner wall of the lower end piston of the upper hydraulic cylinder is sealed with the outer wall of the upper core shaft, the upper end of the upper core shaft is screwed into the lower end internal thread of the upper joint of the bridge plug, the upper outer periphery of the upper hydraulic cylinder is suspended on the middle outer periphery of the upper joint of the bridge plug by pins, an upper hydraulic chamber is provided between the bottom of the upper joint of the bridge plug and the top of the piston of the upper hydraulic cylinder, the upper circumference of the upper core shaft is provided with an upper core shaft pressure transmission hole which is connected with the upper hydraulic chamber; the inner wall of the lower core shaft below the pressure transmission hole of the lower core shaft is provided with a conical trumpet mouth for sealing the steel ball.

[0018] As a further improvement of the present invention, the drillable intubation oil production bridge plug is sealed above the oil layer and below the water-producing layer. A intubation is inserted into the central production tube after the intubation is released. The outer wall of the intubation is embedded with multiple sealing rings to achieve sealing with the inner wall of the central production tube. A flow purifier is provided above the intubation, and a telescopic compensator is provided above the flow purifier. A pump is provided above the telescopic compensator. The top of the pump is connected to the tail pipe and supported on the inner wall of the casing by a hydraulic anchor. The telescopic compensator includes a compensating upper joint, a compensating inner tube, a compensating outer tube and a compensating lower joint. The upper end of the compensating inner tube The compensating outer tube is screwed into the internal thread at the lower end of the compensating upper joint, and the compensating outer tube is sleeved on the outer circumference of the compensating inner tube. The internal thread at the lower end of the compensating outer tube is screwed into the upper external thread section of the compensating lower joint. The upper end of the compensating outer tube is provided with a compensating outer tube sealing section with a reduced diameter, and the inner wall of the compensating outer tube sealing section is embedded with an outer tube sealing ring to achieve sealing with the compensating inner tube. An outer tube stuffing box is provided above the compensating outer tube sealing section, and the outer tube stuffing box is filled with a V-shaped sealing assembly. A parallel ring is screwed into the internal thread mouth above the outer tube stuffing box, and the lower end of the parallel ring presses against the V-shaped sealing assembly to tighten it.

[0019] As a further improvement of the present invention, a gap is provided between the middle section of the compensating inner tube and the compensating outer tube, a compensating inner tube convex ring is provided at the lower end of the compensating inner tube, the compensating inner tube convex ring abuts against the inner wall of the compensating outer tube, the lower port of the compensating inner tube convex ring is evenly provided with an inner tube convex ring lower embedding groove, and the upper port of the compensating lower joint is evenly provided with a compensating lower joint upper embedding groove corresponding to the inner tube convex ring lower embedding groove; the upper end step of the compensating inner tube convex ring is evenly provided with an inner tube convex ring upper embedding groove, and the lower step of the compensating outer tube sealing section is evenly provided with a compensating outer tube sealing section lower embedding groove corresponding to the inner tube convex ring upper embedding groove.

[0020] Another object of the present invention is to overcome the problems existing in the prior art and provide a plugging and oil production method for oil wells with multiple water production points. The next trip of the tubing string can plug the leaking section above the cementing section, and after plugging the leak, the isolation of the water-producing layer below and the oil production of the oil-producing layer can be directly entered, which greatly saves the operation cycle.

[0021] In order to solve the above technical problems, a plugging and oil production method for a multi-point water-outlet oil well of the present invention comprises the following steps in sequence:

[0022] S1. Determine that a leaking section appears above the casing cementing section, and a water-producing layer appears in the casing cementing section;

[0023] S2. Complete the plugging of the leaking section above the casing cementing section;

[0024] S3, completing the plugging of the water-producing layer in the casing cementing section;

[0025] S4, producing oil from the adjacent oil layer below the water-producing layer;

[0026] S5. Continue to produce oil from the next oil layer.

[0027] As an improvement of the present invention, step S2 specifically includes the following sub-steps:

[0028] S2.1. Deliver the integrated seating and squeezing tool as claimed in claim 3 to the bottom of the leaking section through a pipe string and to the top of the water-producing layer of the cementing section;

[0029] S2.2. Pressurize the inside of the pipe string. The upper and lower hydraulic chambers of the seating and squeezing integrated tool build up pressure at the same time to cut the shear nails. Then the upper and lower hydraulic cylinders of the seating and squeezing push tubes are jointly pushed to slide downward. The sealing ring is pressed downward to make the middle section of the long rubber tube of the seating and squeezing bulge outward to achieve the seating and squeezing. The upper and lower slips of the seating and squeezing are anchored on the inner wall of the casing.

[0030] S2.3, as the wellhead pressure increases, the seating tension ring is pulled off, the seating bridge plug mandrel and the seating sealing mechanism remain in the well, the seating upper joint, seating upper mandrel, seating lower mandrel, seating tension ring, seating upper hydraulic cylinder, seating lower hydraulic cylinder and seating push tube are lifted up along with the pipe string for a distance, and the sealing plug falls down;

[0031] S2.4, inject water into the well through the central hole of the upper joint, the upper mandrel and the lower mandrel, calculate the water absorption of the leaking section, and then replace a certain amount of mortar. After lifting the pipe string to a safe height, pressurize the wellhead to squeeze the mortar into the leaking section to plug the leak;

[0032] S2.5. After the cement slurry is ready to set, the pipe string is pulled out, and the upper joint, upper mandrel, lower mandrel, tension ring, upper hydraulic cylinder, lower hydraulic cylinder and push tube are squeezed out of the wellhead along with the pipe string;

[0033] S2.6. Use the lower flat-bottomed grinding shoe to drill through the mortar to the top of the core shaft of the bridge plug, and then test the wellbore pressure to 20MPa. After stabilizing the pressure for 30 minutes, if the pressure drop is less than 0.5MPa, it is judged to be plugging qualified;

[0034] S2.7. Lengthen the tubing string and drill directly through the core shaft of the bridge plug to penetrate the wellbore.

[0035] As a further improvement of the present invention, step S3 specifically includes the following sub-steps:

[0036] S3.1, in the next trip of the tubing string, lower the drillable bridge plug to the lower part of the adjacent oil layer below the water-producing layer and seal it;

[0037] S3.2, lower the drillable pipe-inserted oil production bridge as claimed in claim 5 to the top of the oil layer 1 and below the water-producing layer;

[0038] S3.3. Throw a steel ball into the pipe column, and let it fall to the conical bell mouth of the lower mandrel and seal it;

[0039] S3.4, the pin is cut off by the pressure at the wellhead, and the upper and lower hydraulic cylinders jointly push the plunger tube downward, the plunger push ring is pressed downward, and the middle section of the plunger long rubber tube bulges outward to achieve sealing; the upper and lower slips of the plunger are anchored on the inner wall of the casing;

[0040] S3.5. As the wellhead pressure increases, the plugging shear ring is pulled off and the upper part is released. The plugging center pipe and the plugging sealing mechanism remain in the well. The plugging bridge plug upper joint, plugging upper core shaft, plugging lower core shaft, conversion joint, plugging shear ring, plugging upper hydraulic cylinder, plugging lower hydraulic cylinder and plugging push tube are lifted out of the wellhead along with the pipe string.

[0041] As a further improvement of the present invention, step S4 specifically includes the following sub-steps:

[0042] S4.1. Connect the intubation pipe, the over-current purifier, the telescopic compensator, the oil pump and the hydraulic anchor in sequence at the wellhead and lower them into the well, using the telescopic compensator as claimed in claim 7, and during the well-entering process, the inner compensating pipe is in the lower limit position;

[0043] S4.2. The lower end of the plug is inserted from the plug-in production center pipe of the drillable plug-in production bridge plug. Several sealing rings are embedded on the outer periphery of the plug-in pipe to achieve sealing with the inner wall of the plug-in production center pipe.

[0044] S4.3. Wellhead pressure test to verify that the seal between the insertion pipe and the insertion and production center pipe is reliable;

[0045] S4.4. Lift the pipe column for a distance to make the telescopic compensator in the middle free compensation position;

[0046] S4.5. Pressurize the wellhead to anchor the hydraulic anchor seal on the inner wall of the casing;

[0047] S4.6. Start the oil pump to produce oil.

[0048] As a further improvement of the present invention, step S5 specifically includes the following sub-steps:

[0049] S5.1. Drill and grind the pipe string, drill and grind away the drillable pipe production bridge plug, the drillable bridge plug and the gray surface below, and penetrate the wellbore of the oil layer 2 below the oil layer 1;

[0050] S5.2, in the next trip of the string, lower the new drillable bridge plug below the oil layer 2 and seal it;

[0051] S5.3, the next trip of tubing string is carried out to lower the new drillable plugged oil production bridge to the top of the oil layer 2 and below the upper adjacent oil layer 1;

[0052] S5.4, repeat steps S3.3 to S3.5;

[0053] S5.5. Repeat steps S4.1 to S4.6.

[0054] Compared with the prior art, the present invention has achieved the following beneficial effects: 1. During the cementing construction process, in order to save costs, the cement slurry is raised from the bottom of the well along the annulus to a certain distance above the oil layer and then the grouting is stopped. There is a long section of casing above the oil layer that is not protected by the cementing cement ring. If the bare casing section leaks, it must be sealed. The integrated seating and squeezing tool of the present invention has changed the previous construction method of drilling a metal bridge plug, which requires the bridge plug drilling string to be pulled out, and then the lime injection string to be lowered, first filling sand to protect the metal bridge plug, and then lime injection and lime squeezing; the sealing tool is cleverly used in conjunction with the bridge plug, and the next trip of the string can achieve the purpose of sealing, lime injection, and lime squeezing to plug leaks. Compared with the traditional process, a single operation saves nearly 40,000 yuan, greatly reduces the well occupation period, and avoids the risk of the bridge plug not being salvaged.

[0055] 2. When the water-producing layer is close to the oil layer, other plugging measures are difficult to implement. If the water-producing layer is plugged, it is easy to damage the oil layer, or at least reduce the output of the oil layer. The drillable cannula oil production of the present invention can be quickly sealed between the water-producing layer and the oil layer. The setting and releasing are very reliable, convenient and fast. After setting, the cannula can be directly lowered for oil production without affecting the output of the oil layer. When it is necessary to exploit the next oil layer, there is no need to lower the special salvage tool. It is only necessary to directly lower the grinding shoe to grind off the bridge plug drill, which can at least reduce the number of pipes, save the operation cycle and operation cost, and is especially suitable for oil wells with changed well casing and difficult to salvage.

[0056] 3. The present invention installs a telescopic compensator between the oil pump and the cannula. The vibration caused by the operation of the oil pump can be absorbed by the telescopic compensator. During the production process, the creep of the pipe string can only be transmitted to the telescopic compensator. The cannula and the central pipe of the drillable cannula oil production bridge plug can always be in a static sealing state. The sealing ring on the outer periphery of the cannula is not easy to wear, thereby extending the sealing performance of the cannula bridge plug. When necessary, the telescopic compensator can also transmit torque to meet the needs of rotating the pipe string and downhole tools. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The accompanying drawings are only provided for reference and explanation and are not intended to limit the present invention.

[0058] Figure 1 It is a cross-sectional view of the sitting and squeezing integrated tool of the present invention;

[0059] Figure 2 It is a cross-sectional view of the drillable pipe-inserted oil production bridge plug of the present invention;

[0060] Figure 3 is a cross-sectional view of the telescopic compensator of the present invention;

[0061] Figure 4 for Figure 3 A magnified view of the compensation inner tube;

[0062] Figure 5 for Figure 3 A magnified view of the middle compensation lower joint;

[0063] Figure 6 This is a working state diagram of the present invention during oil production by intubation.

[0064] In the figure: A. hydraulic anchor; B. oil well pump; C. telescopic compensator; D. over-current purifier; E. drillable pipe oil production bridge plug; F. drillable bridge plug; 1. upper joint; 1a. upper joint sealing ring; 2. upper hydraulic cylinder; 2a. upper hydraulic cylinder piston; 3. shear nail; 4. upper mandrel; 4a. upper mandrel pressure transmission hole; 5. mandrel piston; 6. lower hydraulic cylinder; 6a. lower hydraulic cylinder piston; 6b. lower hydraulic cylinder Cylinder through hole; 7. Seating the lower mandrel; 7a. Seating the pressure transmission hole of the lower mandrel; 8. Seating the push cylinder; 9. Seating the tension ring; 10. Seating the bridge plug mandrel; 10a. Seating the bridge plug mandrel convex ring; 11. Seating the sealing ring; 12. Seating the upper slip; 13. Seating the upper cone; 14. Seating the short rubber cylinder; 15. Seating the long rubber cylinder; 16. Seating the lower cone; 17. Seating the lower slip; 18. Seating the guide head; 19. Sealing plug; 20. Casing;

[0065] 21. Compensation upper joint; 22. Compensation upper joint sealing ring; 23. Combination ring; 24. V-shaped sealing assembly; 25. Sealing spacer ring; 26. Compensation outer tube; 27. Outer tube sealing ring; 28. Compensation inner tube; 238a. Upper embedded groove of inner tube convex ring; 28b. Compensation inner tube convex ring; 28c. Lower embedded groove of inner tube convex ring; 29. ​​Compensation lower joint; 29a. Upper embedded groove of compensation lower joint; 30. Compensation lower joint sealing ring;

[0066] 31. Upper joint of the plug-in bridge; 31a. Sealing ring of the upper joint of the plug-in bridge; 32. Upper hydraulic cylinder; 32a. Piston of the upper hydraulic cylinder; 32b. Pressure relief hole of the upper hydraulic cylinder; 33. Pin; 34. Upper mandrel; 34a. Pressure transmission hole of the upper mandrel; 34b. Piston of the upper mandrel; 35. Lower hydraulic cylinder; 35a. Piston of the lower hydraulic cylinder; 35b. Through hole of the lower hydraulic cylinder; 36. Lower mandrel; 36a. Pressure transmission hole of the lower mandrel hole; 37. Insertion and mining push tube; 37a. Insertion and mining push tube long groove; 38. Conversion joint; 38a. Conversion joint radial hole; 39. Insertion and mining shear ring; 40. Insertion and mining center tube; 40a. Insertion and mining center tube convex ring; 41. Insertion and mining push ring; 42. Insertion and mining upper slip; 43. Insertion and mining upper cone; 44. Upper short rubber tube; 45. Insertion and mining long rubber tube; 46. Lower short rubber tube; 47. Insertion and mining lower cone; 48. Insertion and mining lower slip; 49. Insertion and mining guide shoe; 50. Steel ball. DETAILED DESCRIPTION

[0067] In the following description of the present invention, the directions or positional relationships indicated by terms such as "up", "down", "front", "back", "left", "right", "inside" and "outside" are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, and do not mean that the device must have a specific direction.

[0068] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below with reference to specific diagrams.

[0069] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0070] like Figure 1 As shown, the integrated seating and squeezing tool in the present invention includes a seating and squeezing bridge plug core shaft 10, the outer circumference of the lower end of the seating and squeezing bridge plug core shaft 10 is rotatably connected with a seating and squeezing guide head 18, and the lower end of the seating and squeezing guide head 18 is provided with a pen tip to facilitate guiding the tool into the well smoothly; the upper end inner cavity of the seating and squeezing bridge plug core shaft 10 is provided with a blind plate to close the center hole of the seating and squeezing bridge plug core shaft 10, and the blind plate serves as the bottom of the well for ash injection after seating; the upper end of the seating and squeezing bridge plug core shaft 10 is also provided with a seating and squeezing bridge plug core shaft convex ring 10a extending upwardly with a diameter expansion, a seating ring 11 is provided under the step of the seating and squeezing bridge plug core shaft convex ring 10a, and a seating and squeezing seating mechanism is provided between the seating ring 11 and the seating and squeezing guide head 18.

[0071] The seating sealing mechanism includes a long seating rubber cylinder 15 which is sleeved on the outer circumference of the seating bridge plug core shaft 10. Both ends of the long seating rubber cylinder 15 are embedded in the short seating rubber cylinder 14. An upper seating cone 13 is provided above the upper short seating rubber cylinder 14. The small end of the upper seating cone 13 faces upward and cooperates with the lower inner cone surface of the upper seating slip 12. The top of the upper seating slip 12 abuts against the bottom of the seating ring 11; a lower seating cone 16 is provided below the lower short seating rubber cylinder. The small end of the lower seating cone 16 faces downward and cooperates with the upper inner cone surface of the lower seating slip 17. The bottom of the lower seating slip 17 abuts against the top of the seating guide head 18.

[0072] The outer circumference of the convex ring 10a of the seating bridge plug core shaft is sleeved with a seating push cylinder 8, the lower end of the seating push cylinder 8 abuts against the upper end surface of the seating ring 11, and the upper end of the seating push cylinder 8 is screwed together with the outer circumference of the seating lower hydraulic cylinder piston 6a; the upper circumference of the seating push cylinder 8 is provided with a seating push cylinder through hole which is connected with the space below the seating lower hydraulic cylinder piston 6a to avoid pressure build-up during the downward movement of the seating lower hydraulic cylinder piston 6a.

[0073] The inner thread of the convex ring 10a of the seat bridge plug mandrel is screwed with a seat tension ring 9, the inner wall of the upper end of the seat tension ring 9 is screwed with the seat lower mandrel 7, the inner wall of the seat lower hydraulic cylinder piston 6a is embedded with a seat lower hydraulic cylinder sealing ring to achieve sealing with the upper outer wall of the seat lower mandrel 7, the upper end of the seat lower mandrel 7 is screwed with the seat upper mandrel 4, the upper end of the seat lower mandrel 7 is screwed with the seat mandrel piston 5, and the outer wall of the seat mandrel piston 5 is embedded with a piston The outer sealing ring is sealed with the inner wall of the cylinder of the sitting and squeezing lower hydraulic cylinder 6, the upper inner wall of the sitting and squeezing core shaft piston 5 is embedded with the piston inner sealing ring and sealed with the outer wall of the sitting and squeezing upper core shaft 4, the cylinder of the sitting and squeezing lower hydraulic cylinder 6 is connected as a whole with the sitting and squeezing lower hydraulic cylinder piston 6a; a lower hydraulic chamber is provided between the bottom of the sitting and squeezing core shaft piston 5 and the top of the sitting and squeezing lower hydraulic cylinder piston 6a, and a sitting and squeezing lower core shaft pressure transmission hole 7a is provided on the upper circumference of the sitting and squeezing lower core shaft 7, which is connected with the lower hydraulic chamber.

[0074] The inner cavity at the lower end of the seat extrusion lower mandrel 7 is provided with a sealing plug 19, and a plug sealing ring is embedded in the upper outer periphery of the sealing plug 19 to achieve sealing with the inner wall of the seat extrusion lower mandrel 7. The middle outer periphery of the sealing plug 19 is provided with a plug convex ring, which is located below the seat extrusion lower mandrel 7 and embedded in the groove of the seat extrusion tension ring 9, so that the sealing plug 19 is axially positioned, and the lower end large diameter section of the sealing plug 19 fits in the inner cavity of the seat extrusion tension ring 9. The groove of the seating tension ring 9 is the weakest part. When the pipe column is pressed to a certain pressure, the plug convex ring and the groove of the seating tension ring 9 are broken, and the sealing plug 19 falls down, so that the central channel of the seating upper joint 1, the seating upper mandrel 4 and the seating lower mandrel 7 is opened. There is no need to re-inject cement into the pipe column. The upper seating joint 1, the seating upper mandrel 4 and the seating lower mandrel 7 after being thrown away by the tool can be directly used for cement injection and cement squeezing. Since the aperture of the central channel of the seating upper joint 1, the seating upper mandrel 4 and the seating lower mandrel reaches 42mm, it can fully meet the demand of injecting cement slurry into the leaking section, and one trip to the pipe column is omitted.

[0075] The sealing plug 19 reliably seals the central channel above the seated mandrel 7 of the tool, making it easy to pressurize the wellhead to cut off the shear pins 3.

[0076] The well retaining components such as the seating bridge plug core shaft 10 and the seating seal mechanism are all made of fast-drilling composite materials to facilitate subsequent drilling and removal.

[0077] The upper end of the sitting and squeezing lower hydraulic cylinder 6 is screwed with the sitting and squeezing upper hydraulic cylinder piston 2a, and the inner wall of the sitting and squeezing upper hydraulic cylinder piston 2a is embedded with the sitting and squeezing upper hydraulic cylinder sealing ring and the outer wall of the sitting and squeezing upper core shaft 4 to achieve sealing, the upper end of the sitting and squeezing upper core shaft 4 is screwed into the lower end internal thread of the sitting and squeezing upper joint 1, the upper end outer periphery of the sitting and squeezing upper hydraulic cylinder piston 2a is connected as a whole with the barrel of the sitting and squeezing upper hydraulic cylinder 2, and the lower end sealing section of the sitting and squeezing upper joint 1 is embedded with the sitting and squeezing upper joint sealing ring 1a and the inner wall of the sitting and squeezing upper hydraulic cylinder 2 to achieve sealing.

[0078] The upper periphery of the upper hydraulic cylinder 2 is suspended on the middle periphery of the upper joint 1 by shear nails 3, an upper hydraulic chamber is provided between the bottom of the upper joint 1 and the top of the upper hydraulic cylinder piston 2a, and an upper mandrel pressure transmission hole 4a is provided on the upper circumference of the upper mandrel 4 and is connected with the upper hydraulic chamber.

[0079] The outer diameters of the upper joint 1, the upper hydraulic cylinder 2 and the lower hydraulic cylinder 6 are 108 mm, which can reduce the pumping effect when pulling the pipe upwards and avoid affecting the plugging effect. The inner wall of the center hole of the upper joint 1 is flush with the inner wall of the upper mandrel 4 and the lower mandrel 7 to ensure that the cement slurry has a sufficient diameter, ensuring the efficiency and safety of cement injection.

[0080] The lower circumference of the seating lower hydraulic cylinder 6 is provided with a seating lower hydraulic cylinder through hole 6b which is communicated with the upper cavity of the seating core shaft piston 5. During the expansion process of the upper hydraulic cavity and the lower hydraulic cavity, the upper cavity of the seating core shaft piston 5 is prevented from being pressurized.

[0081] like Figure 2 As shown, the drillable intubation oil production bridge plug E in the present invention comprises an intubation production center tube 40, a intubation production guide shoe 49 is rotatably connected to the outer circumference of the lower end of the intubation production center tube 40, an intubation production center tube convex ring 40a with an enlarged diameter is provided at the upper end of the intubation production center tube 40, an intubation production push ring 41 is provided below the step of the intubation production center tube convex ring 40a, and an intubation production sealing mechanism is provided between the intubation production push ring 41 and the intubation production guide shoe 49.

[0082] The plugging and sealing mechanism includes a long plugging rubber cylinder 45 which is sleeved on the outer periphery of the plugging center tube 40. Both ends of the long plugging rubber cylinder 45 are embedded in the short rubber cylinder. An upper plugging cone 43 is provided above the upper short rubber cylinder 44. The small end of the upper plugging cone 43 faces upward and cooperates with the lower inner cone surface of the upper plugging slip 42. The top of the upper plugging slip 42 abuts against the bottom of the plugging push ring 41; a lower plugging cone 47 is provided on the side of the lower short rubber cylinder 46. The small end of the lower plugging cone 47 faces downward and cooperates with the upper inner cone surface of the lower plugging slip 48. The bottom of the lower plugging slip 48 abuts against the top of the plugging guide shoe 49.

[0083] The outer periphery of the convex ring 40a of the central tube for plugging and mining is sleeved with a plugging and mining push cylinder 37, the lower end of which abuts against the upper end surface of the plugging and mining push ring 41, and the upper end of the plugging and mining push cylinder 37 is screwed with the outer periphery of the plugging and mining lower hydraulic cylinder 35; a plugging and mining shear ring 39 is screwed into the internal thread of the convex ring 40a of the central tube for plugging and mining, and a conversion joint 38 is screwed into the inner wall of the upper end of the plugging and mining shear ring 39, the lower end of the conversion joint 38 is closed, and the upper end of the conversion joint 38 is screwed with the plugging and mining lower mandrel 36, and the upper part of the plugging and mining lower mandrel 36 is screwed into the upper end of the conversion joint 38. The outer wall is sealed with the inner wall of the piston of the lower liquid cylinder 35, the upper end outer circumference of the lower mandrel 36 is swivel-connected with the upper mandrel 34, the lower part of the upper mandrel 34 is provided with an upper mandrel piston 34b, the outer wall of the upper mandrel piston 34b is sealed with the lower liquid cylinder 35, a lower hydraulic chamber is provided between the bottom of the piston of the upper mandrel 34 and the top of the piston of the lower liquid cylinder 35, and the upper circumference of the lower mandrel 36 is provided with a lower mandrel pressure transmission hole 36a connected to the lower hydraulic chamber. The central hole of the lower mandrel 36 is small, and the aperture of the central tube 40 is large. The conversion of the large and small apertures is achieved by the conversion joint 38, so that the central tube 40 can have a larger aperture, which is convenient for inserting the cannula and has a larger actual diameter.

[0084] The circumferential wall of the plugging and mining lower liquid cylinder 35 is connected with the plugging and mining lower liquid cylinder piston 35a at the bottom and slides synchronously. The plugging and mining central pipe 40 and the plugging and mining setting mechanism are all made of composite materials, and no fishing tools are required, and they can be directly ground off by grinding shoes.

[0085] The upper end of the plugging lower hydraulic cylinder 35 is screwed with the plugging upper hydraulic cylinder 32, and the lower end of the plugging upper hydraulic cylinder 32 is provided with the plugging upper hydraulic cylinder piston 2a. The inner wall of the plugging upper hydraulic cylinder piston 2a is sealed with the outer wall of the plugging upper mandrel 34. The upper end of the plugging upper mandrel 34 is screwed into the lower end internal thread of the plugging bridge plug upper joint 31. The upper outer periphery of the plugging upper hydraulic cylinder 32 is suspended on the middle outer periphery of the plugging bridge plug upper joint 31 through a pin 33. An upper hydraulic chamber is provided between the bottom of the plugging bridge plug upper joint 31 and the top of the plugging upper hydraulic cylinder piston 2a. The upper circumference of the plugging upper mandrel 34 is provided with a plugging upper mandrel pressure transmission hole 34a connected to the upper hydraulic chamber. The circumferential wall of the plugging upper hydraulic cylinder 32 is connected to the lower plugging upper hydraulic cylinder piston 2a as a whole and slides synchronously. The upper plugging mandrel 34 is connected to the upper plugging mandrel piston 34 b at its lower portion as a whole, and the outer wall of the upper plugging mandrel piston 34 b slides relatively with the lower plugging cylinder 35 .

[0086] A conical bell mouth is provided on the inner wall of the lower core shaft 36 below the pressure transmission hole 36a of the lower core shaft. When sealing is required, a steel ball 50 is dropped from the wellhead, and the steel ball 50 falls onto the conical bell mouth of the lower core shaft 36 to seal and generate pressure build-up.

[0087] A conversion joint radial hole 38a is provided on the middle circumference of the conversion joint 38, which is connected to the center hole of the conversion joint 38. A plurality of insertion and extraction push tube long grooves 37a are evenly distributed on the middle circumference of the insertion and extraction push tube 37, which are connected to the cavity between the bottom of the insertion and extraction lower fluid cylinder 35 and the top of the insertion and extraction center pipe convex ring 40a. When the pipe string is lowered, the insertion and extraction push tube long grooves 37a and the conversion joint radial holes 38a communicate the inside and outside of the pipe string, ensuring the pressure balance inside and outside the pipe string, avoiding the generation of buoyancy, and no need to fill the wellhead with water.

[0088] The lower sealing section of the upper joint 31 of the plug-in bridge is embedded with the upper joint sealing ring 31a on the outer periphery to achieve sealing with the inner wall of the upper hydraulic cylinder 32; the lower piston inner wall of the upper hydraulic cylinder 32 is embedded with the upper hydraulic cylinder sealing ring to achieve sealing with the outer wall of the upper core shaft 34, thereby sealing the upper and lower ends of the upper hydraulic chamber.

[0089] The outer wall of the lower piston of the upper plugging core shaft 34 is embedded with the plugging core shaft sealing ring and the inner wall of the plugging lower hydraulic cylinder 35 to achieve sealing. The inner wall of the piston of the plugging lower hydraulic cylinder 35 is embedded with the plugging lower hydraulic cylinder sealing ring and the upper outer wall of the plugging lower core shaft 36 to achieve sealing, so that the upper and lower ends of the lower hydraulic chamber are sealed.

[0090] A reduced diameter section of the upper joint of the plugging bridge plug is provided between the upper sealing section of the lower part of the plugging bridge plug and the circumference of the pin connection, and a pressure relief hole 32b of the upper hydraulic cylinder 32 is provided on the circumference of the plugging bridge plug, which is communicated with the upper part of the reduced diameter section of the upper joint of the plugging bridge plug. A through hole 35b of the lower hydraulic cylinder 35 is provided on the upper circumference of the plugging bridge plug, which is communicated with the upper cavity of the plugging upper mandrel piston 34b.

[0091] During the process of lowering the pipe string into the well, the upper cavity of the upper mandrel piston 34b is connected to the annulus through the through hole 35b of the lower hydraulic cylinder to prevent the generation of pressure build-up. During the sealing process, the upper mandrel 34 and the lower mandrel 36 remain stationary, the upper hydraulic cylinder 32 and the lower hydraulic cylinder 35 slide downward, and the sealing mechanism is driven to sit through the thrust cylinder 37, and the height of the upper hydraulic chamber and the lower hydraulic chamber gradually increases. After the sealing anchoring of the long rubber cylinder 45 is completed and the shear ring 39 is broken, the pressure relief hole 32b of the upper hydraulic cylinder slides downward to a position flush with the upper hydraulic chamber, realizing the pressure relief of the central channel above the steel ball 50, and the ground personnel can judge that the sealing has been completed.

[0092] Since the distance between the through hole 35b of the lower hydraulic cylinder and the top of the upper core shaft piston 34b is greater than the distance between the pressure relief hole 32b of the upper hydraulic cylinder and the sealing section of the upper joint of the bridge plug, before and after the sealing of the long rubber cylinder 45 is completed, the through hole 35b of the lower hydraulic cylinder is always connected to the upper cavity of the upper core shaft piston 34b.

[0093] like Figures 3 to 5As shown, the telescopic compensator C in the present invention includes a compensating upper joint 21, a compensating inner tube 28, a compensating outer tube 26 and a compensating lower joint 29. The upper end of the compensating inner tube 28 is screwed into the lower end internal thread of the compensating upper joint 21, the compensating outer tube 26 is sleeved on the outer circumference of the compensating inner tube 28, the lower end internal thread of the compensating outer tube 26 is screwed into the upper external thread section of the compensating lower joint 29, the upper end of the compensating outer tube 26 is provided with a compensating outer tube sealing section with a reduced diameter, the inner wall of the compensating outer tube sealing section is embedded with an outer tube sealing ring 27 to achieve sealing with the compensating inner tube 28, an outer tube stuffing box is provided above the compensating outer tube sealing section, the outer tube stuffing box is filled with a V-shaped sealing assembly 24, a parallel ring 23 is screwed into the upper inner thread of the outer tube stuffing box, and the lower end of the parallel ring 23 abuts against the V-shaped sealing assembly 24 to press it.

[0094] The compensating upper joint 21 is fixedly connected to the compensating inner tube 28, and a compensating upper joint sealing ring 22 is embedded above the lower internal thread section of the compensating upper joint 21 to seal with the upper end of the compensating inner tube 28. The compensating upper joint 21 is screwed to the tail pipe above, and the tail pipe creep caused by the vibration of the oil pump will be transmitted to the compensating inner tube 28 through the compensating upper joint 21, that is, the compensating inner tube 28 will creep along with the tail pipe above.

[0095] The compensating outer tube 26 is fixedly connected to the compensating lower joint 29, and a compensating lower joint sealing ring 30 is embedded above the upper external threaded section of the compensating lower joint 29 to seal with the lower inner wall of the compensating outer tube 26. The lower end of the compensating lower joint 29 is fixedly connected to the inserting tube. When the inserting tube is inserted into the inserting and production center tube 40 of the drillable inserting and production bridge plug E, the multiple sealing rings embedded on the outer periphery of the inserting tube and the inner wall of the inserting and production center tube 40 are sealed.

[0096] The compensation outer tube 26 and the compensation inner tube 28 are sealed by the outer tube sealing ring 27 and the V-shaped sealing assembly 24. The V-shaped sealing assembly 24 plays a major sealing role and is divided into two sections with opposite openings. The upper group opens upward, and the lower group opens downward. A sealing spacer ring 25 is provided between the two groups. The upper port of the compensation outer tube 26 is pressed tightly by the V-shaped sealing assembly 24 by the ring 23.

[0097] A ring flange is provided at the upper end of the ring 23, and ring grooves are evenly provided on the circumference of the ring flange to facilitate the rotation of the ring 23 by a tool.

[0098] Although the compensation outer tube 26 and the compensation inner tube 28 are sealed, when the upper tail pipe creeps, the compensation inner tube 28 can slide axially in the compensation outer tube 26 to prevent the creep from being transmitted to the compensation outer tube 26. The compensation outer tube 26, the compensation lower joint 29 and the cannula remain stationary to prevent the sealing ring on the outer periphery of the cannula from being worn. The cannula and the cannula production center tube 40 of the drillable cannula production bridge plug E are always in a static sealing state, thereby extending the sealing performance of the cannula production bridge plug. The drillable cannula production bridge plug E will not fail, and the sealing assembly of the telescopic compensator C has a wear compensation function, which greatly extends the service life of the cannula production bridge plug.

[0099] A gap is provided between the middle section of the compensating inner tube 28 and the compensating outer tube 26. A compensating inner tube convex ring 28b is provided at the lower end of the compensating inner tube 28. The compensating inner tube convex ring 28b abuts against the inner wall of the compensating outer tube 26. The compensating inner tube convex ring 28b slides along the inner wall of the compensating outer tube 26. When performing telescopic compensation, the compensating inner tube 28 can always be kept coaxial with the compensating outer tube 26 to avoid shaking.

[0100] When the compensating inner tube convex ring 28b moves downward to abut against the upper end of the compensating lower joint 29, the compensating inner tube 28 reaches the lower limit position; when the compensating inner tube convex ring 28b moves downward to abut against the lower inner step of the compensating outer tube sealing section, the compensating inner tube 28 reaches the upper limit position; the free section of compensation is between the upper and lower limit positions.

[0101] The lower end of the compensating inner tube convex ring 28b is uniformly provided with inner tube convex ring lower embedding grooves 28c, and inner tube convex ring lower tenons are formed between adjacent inner tube convex ring lower embedding grooves 28c. For example, four inner tube convex ring lower embedding grooves 28c and four inner tube convex ring lower tenons of equal width can be provided. The upper end of the compensating lower joint 29 is uniformly provided with compensating lower joint upper embedding grooves 29a, and compensating lower joint upper tenons are formed between adjacent compensating lower joint upper embedding grooves 29a. When entering the well, when the compensating lower joint upper tenon is embedded in the inner tube convex ring lower embedding groove 28c, the inner tube convex ring lower tenon is also embedded in the compensating lower joint upper embedding groove 29a, and the compensating inner tube 28 is radially locked to prevent the compensating lower joint from rotating. When the cannula is inserted into the insertion center pipe 40 of the drillable cannula oil production bridge plug E, torque can be transmitted, which is convenient for insertion.

[0102] The upper end step of the compensating inner tube convex ring 28b is evenly provided with inner tube convex ring upper embedded grooves 238a, and inner tube convex ring upper tenons are formed between adjacent inner tube convex ring upper embedded grooves 238a; the lower step of the compensating outer tube sealing section is evenly provided with compensating outer tube sealing section lower embedded grooves, and compensating outer tube sealing section lower tenons are formed between adjacent compensating outer tube sealing section lower embedded grooves.

[0103] When the compensating inner tube 28 reaches the upper limit position, when the lower tenon of the compensating outer tube sealing section is embedded in the upper embedding groove 238a of the inner tube convex ring, the upper tenon of the inner tube convex ring is also correspondingly embedded in the lower embedding groove of the compensating outer tube sealing section to form a tooth-type connection. In this way, when encountering an unexpected situation underground and needing to lower other tools or instruments, the compensating inner tube 28 can be lifted to the upper limit position to transmit torque.

[0104] The method for plugging and producing oil from a multi-point water-outlet oil well of the present invention comprises the following steps in sequence:

[0105] S1. Determine that a leaking section appears above the casing cementing section, and a water-producing layer appears in the casing cementing section;

[0106] S2. Complete the plugging of the leaking section above the casing cementing section;

[0107] S3, completing the plugging of the water-producing layer in the casing cementing section;

[0108] S4, producing oil from the adjacent oil layer below the water-producing layer;

[0109] S5. Continue to produce oil from the next oil layer.

[0110] Step S2 specifically includes the following sub-steps:

[0111] S2.1. Deliver the integrated seating and squeezing tool as claimed in claim 3 to the bottom of the leaking section through a pipe string and to the top of the water-producing layer of the cementing section;

[0112] S2.2. Pressurize the inside of the pipe column. The hydraulic pressure enters the upper hydraulic chamber through the pressure transmission hole 4a of the upper mandrel and enters the lower hydraulic chamber through the pressure transmission hole 7a of the lower mandrel. Since the upper joint 1, the upper mandrel 4, the lower mandrel 7, the tension ring 9 and the bridge plug mandrel 10 are suspended by the pipe column and remain motionless, the upper hydraulic chamber applies a downward thrust to the piston 2a of the upper hydraulic cylinder, and the lower hydraulic chamber applies a downward thrust to the piston 6a of the lower hydraulic cylinder, first cutting the shear nail 3, and then the upper hydraulic cylinder 2 and the lower hydraulic cylinder 6 jointly push the The seating push cylinder 8 slides downward, and the lower end of the seating push cylinder 8 pushes the seating upper slip 12 to move downward along the conical surface of the seating upper cone 13 through the sealing ring 11. Similarly, the seating lower slip 17 moves upward relatively along the conical surface of the seating lower cone 16. At the same time, the large ends of the seating upper cone 13 and the seating lower cone 16 squeeze the seating short rubber cylinder and the seating long rubber cylinder 15 from both sides, and the middle section of the seating long rubber cylinder 15 bulges outward to achieve sealing with the inner wall of the casing 20; the outer wall teeth of the seating upper slip 12 and the seating lower slip 17 are anchored on the inner wall of the casing 20;

[0113] S2.3, the wellhead pressure increases, the seating tension ring 9 is pulled off, the seating bridge plug mandrel 10 and the seating sealing mechanism remain stationary, the seating upper joint 1, the seating upper mandrel 4, the seating lower mandrel 7, the seating tension ring 9, the seating upper hydraulic cylinder 2, the seating lower hydraulic cylinder 6 and the seating push tube 8 are lifted up along with the pipe string for a distance, and the sealing plug 19 falls down;

[0114] S2.4, inject water into the well through the central hole of the upper seat extrusion joint 1, the upper seat extrusion mandrel 4 and the lower seat extrusion mandrel 7 to calculate the water absorption of the leaking section; then replace a certain amount of mortar, lift the pipe string to a safe height, and pressurize the wellhead to squeeze the mortar into the leaking section to plug the leak;

[0115] S2.5. After the cement slurry is ready to set, the pipe string is pulled out, and the upper joint 1, the upper mandrel 4, the lower mandrel 7, the tension ring 9, the upper hydraulic cylinder 2, the lower hydraulic cylinder 6 and the push tube 8 are pulled out of the wellhead along with the pipe string;

[0116] S2.6. Use the lower flat-bottomed grinding shoe to drill through the mortar to the top of the core shaft 10 of the bridge plug, and then test the wellbore pressure to 20 MPa. After stabilizing the pressure for 30 minutes, if the pressure drop is less than 0.5 MPa, it is judged to be plugging qualified;

[0117] S2.7. Lengthen the pipe string, drill directly through the bridge plug core shaft 10, and penetrate the wellbore.

[0118] Step S3 specifically includes the following sub-steps:

[0119] S3.1, in the next trip of the tubing string, lower the drillable bridge plug F to the lower part of the adjacent oil layer 1 below the water-producing layer and set it;

[0120] S3.2, the next trip of tubing string, the drillable plugged oil production bridge plug is lowered to the top of the oil layer 1 and below the water-producing layer;

[0121] S3.3, a steel ball 50 is thrown into the pipe column, and the steel ball 50 falls to the conical bell mouth of the lower mandrel 36 for sealing;

[0122] S3.4, the wellhead is pressurized to cut the pin 33, and the pipe string is fixed to the insertion and production center pipe 40 and the insertion and production guide shoe 49 through the insertion and production bridge plug upper joint 31, the insertion and production upper mandrel 34, the insertion and production lower mandrel 36, the conversion joint 38, and the insertion and production shear ring 39 to keep them stationary. The pressure liquid enters the upper hydraulic chamber through the insertion and production upper mandrel pressure transmission hole 34a, and enters the lower hydraulic chamber through the insertion and production lower mandrel pressure transmission hole 36a. The insertion and production upper hydraulic cylinder 32 and the insertion and production lower hydraulic cylinder 35 jointly push the insertion and production push tube 37 to move downward, and the insertion and production The lower end of the push cylinder 37 pushes the upper insertion slip 42 to move downward along the conical surface of the upper insertion cone 43 through the insertion push ring 41. Similarly, the lower insertion slip 48 moves upward relatively along the conical surface of the lower insertion cone 47. At the same time, the large ends of the upper insertion cone 43 and the lower insertion cone 47 squeeze the short rubber cylinder and the long insertion rubber cylinder 45 from both sides. The middle section of the long insertion rubber cylinder 45 bulges outward and realizes sealing with the inner wall of the casing. The outer wall of the upper insertion slip 42 and the lower insertion slip 48 is anchored on the inner wall of the casing.

[0123] S3.5. As the wellhead pressure increases, the plugging shear ring 39 is pulled off, and the upper part is released. The plugging center pipe 40 and the plugging sealing mechanism remain in the well. The plugging bridge plug upper joint 31, the plugging upper core shaft 34, the plugging lower core shaft 36, the conversion joint 38, the plugging shear ring 39, the plugging upper hydraulic cylinder 32, the plugging lower hydraulic cylinder 35 and the plugging push tube 37 are lifted out of the wellhead along with the pipe string.

[0124] Step S4 specifically includes the following sub-steps:

[0125] S4.1. Connect the intubation pipe, the over-current purifier D, the telescopic compensator C, the oil pump B and the hydraulic anchor A in sequence at the wellhead and lower them into the well. During the lowering of the telescopic compensator C, the inner compensating tube 28 is in the lower limit position to avoid rotation when lowering into the well. The hydraulic anchor A uses the KYLM116 type hydraulic anchor, and the drillable bridge plug F uses the QSA drillable bridge plug.

[0126] S4.2, the lower end of the plug is inserted from the plugging and production center pipe 40 of the drillable plugging and production bridge plug E, and twelve sealing rings are embedded on the outer circumference of the plugging and production center pipe 40 to achieve sealing;

[0127] S4.3. Wellhead pressure test to verify that the seal between the insert pipe and the inserting and production center pipe 40 is reliable;

[0128] S4.4. Lift the pipe column for a distance, for example, 400 mm, so that the convex ring 28b of the compensating inner pipe maintains a suitable distance from the upper port of the compensating lower joint and the lower step of the sealing section of the compensating outer tube, and the telescopic compensator C is in the middle free compensation position;

[0129] S4.5, pressurizing the wellhead to anchor the hydraulic anchor A on the inner wall of the casing 20;

[0130] S4.6. Start the oil pump B to produce oil. When the oil pump B is in production, the peristalsis of the oil pump B can only be transmitted to the telescopic compensator C. The insertion and production center pipe 40 of the drillable insertion and production bridge plug E is in a static sealing state, and the service life of the insertion and production bridge plug is greatly extended. After the oil layer is produced, the production pipe string is pulled out.

[0131] Step S5 specifically includes the following sub-steps:

[0132] S5.1. Drill and grind the pipe string, drill and grind away the drillable pipe production bridge plug E, the drillable bridge plug F, and the gray surface below at one time, and penetrate the wellbore of the oil layer 2 below the oil layer 1;

[0133] S5.2, in the next trip of the string, lower the new drillable bridge plug F to the bottom of the oil layer 2 and set it;

[0134] S5.3, lower the new drillable pipe production bridge plug E to the top of the oil layer 2 and below the adjacent oil layer 1 above;

[0135] S5.4, repeat steps S3.3 to S3.5;

[0136] S5.5. Repeat steps S4.1 to S4.6.

[0137] The above is only a preferred embodiment of the present invention, which shows and describes the basic principles and main features of the present invention and the advantages of the present invention, but does not limit the scope of patent protection of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. In addition to the above embodiments, the present invention may have other implementation modes without departing from the spirit and scope of the present invention. The present invention may also have various changes and improvements, and all technical solutions formed by equivalent substitution or equivalent transformation fall within the scope of protection required by the present invention. The scope of protection required by the present invention is defined by the attached claims and their equivalents. The technical features not described in the present invention can be realized by or using existing technologies, which will not be repeated here.

Claims

1. A plugging and oil production device for a multi-point water-outlet oil well, comprising a sitting and squeezing integrated tool for plugging leaks above the cementing section and a drillable and intubated oil production bridge plug for plugging the water-outlet layer of the cementing section, characterized in that: The integrated seating and squeezing tool comprises a seating and squeezing bridge plug core shaft, the outer circumference of the lower end of the seating and squeezing bridge plug core shaft is swivel-connected with a seating and squeezing guide head, the upper end of the seating and squeezing bridge plug core shaft is closed and provided with a seating and squeezing bridge plug core shaft convex ring extending upward with a larger diameter, a seating and squeezing ring is provided below the step of the seating and squeezing bridge plug core shaft convex ring, a seating and squeezing sealing mechanism is provided between the seating and squeezing ring and the seating and squeezing guide head; a seating and squeezing push cylinder is sleeved on the outer circumference of the seating and squeezing bridge plug core shaft convex ring, the lower end of the seating and squeezing push cylinder abuts against the upper end surface of the seating and squeezing ring, the upper end of the seating and squeezing push cylinder is swivel-connected with the outer circumference of the seating and squeezing lower hydraulic cylinder piston; a seating and squeezing tension ring is swivel-connected with the internal thread of the seating and squeezing bridge plug core shaft convex ring, the upper end inner wall of the seating and squeezing tension ring is swivel-connected with the seating and squeezing lower core shaft, and the upper outer wall of the seating and squeezing lower core shaft is sealed with the inner wall of the seating and squeezing lower hydraulic cylinder piston; The upper end of the sitting and squeezing lower mandrel is rotatably connected to the upper sitting and squeezing mandrel, and the upper end of the sitting and squeezing lower mandrel is rotatably connected to the sitting and squeezing mandrel piston, the outer wall of the sitting and squeezing mandrel piston is sealed with the inner wall of the cylinder of the sitting and squeezing lower hydraulic cylinder, and the cylinder of the sitting and squeezing lower hydraulic cylinder is connected as a whole with the sitting and squeezing lower hydraulic cylinder piston; a lower hydraulic chamber is provided between the bottom of the sitting and squeezing mandrel piston and the top of the sitting and squeezing lower hydraulic cylinder piston, and the upper circumference of the sitting and squeezing lower mandrel is provided with a sitting and squeezing mandrel pressure transmission hole connected to the lower hydraulic chamber; a sealing plug is provided in the inner cavity of the lower end of the sitting and squeezing lower mandrel, and a plug convex ring is provided on the middle outer circumference of the sealing plug, the plug convex ring is located below the sitting and squeezing lower mandrel and embedded in the groove of the sitting and squeezing tension ring, and the lower end large diameter section of the sealing plug fits in the inner cavity of the sitting and squeezing tension ring; The upper end of the sitting and squeezing lower hydraulic cylinder is screwed with the sitting and squeezing upper hydraulic cylinder piston, the inner wall of the sitting and squeezing upper hydraulic cylinder piston is sealed with the outer wall of the sitting and squeezing upper core shaft, the upper end of the sitting and squeezing upper core shaft is screwed into the lower end internal thread of the sitting and squeezing upper joint, the upper end outer periphery of the sitting and squeezing upper hydraulic cylinder piston is connected as a whole with the barrel of the sitting and squeezing upper hydraulic cylinder, the upper outer periphery of the sitting and squeezing upper hydraulic cylinder is suspended on the middle outer periphery of the sitting and squeezing upper joint by shear nails, an upper hydraulic chamber is provided between the bottom of the sitting and squeezing upper joint and the top of the sitting and squeezing upper hydraulic cylinder piston, the upper circumference of the sitting and squeezing upper core shaft is provided with a sitting and squeezing upper core shaft pressure transmission hole connected with the upper hydraulic chamber; the lower circumference of the sitting and squeezing lower hydraulic cylinder is provided with a sitting and squeezing lower hydraulic cylinder through hole connected with the upper cavity of the sitting and squeezing core shaft piston.

2. The leak plugging and oil production device for a multi-point water-outlet oil well according to claim 1 is characterized in that: The outer circumference of the lower end of the insertion and production center tube of the drillable and cannulated oil production bridge plug is screwed with an insertion and production guide shoe, the upper end of the insertion and production center tube is provided with an insertion and production center tube convex ring with an expanded diameter, a insertion and production push ring is provided below the step of the insertion and production center tube convex ring, and an insertion and production sealing mechanism is provided between the insertion and production push ring and the insertion and production guide shoe; the outer circumference of the insertion and production center tube convex ring is sleeved with an insertion and production push cylinder, the lower end of the insertion and production push cylinder abuts against the upper end surface of the insertion and production push ring, and the upper end of the insertion and production push cylinder is screwed with the outer circumference of the insertion and production lower hydraulic cylinder; the insertion and production center tube convex ring is screwed with an insertion and production push cylinder in the inner thread A shear ring, the inner wall of the upper end of the insertion and mining shear ring is screwed with a conversion joint, the upper end of the conversion joint is screwed with a lower insertion and mining core shaft, the upper outer wall of the lower insertion and mining core shaft is sealed with the inner wall of the piston of the lower insertion and mining cylinder, the upper end outer circumference of the lower insertion and mining core shaft is screwed with an upper insertion and mining core shaft, the lower piston outer wall of the upper insertion and mining core shaft is sealed with the lower insertion and mining cylinder, a lower hydraulic chamber is provided between the bottom of the piston of the upper insertion and mining core shaft and the top of the piston of the lower insertion and mining cylinder, and the upper circumference of the lower insertion and mining core shaft is provided with a lower insertion and mining core shaft pressure transmission hole which is connected with the lower hydraulic chamber.

3. The leak plugging and oil production device for a multi-point water-outlet oil well according to claim 2 is characterized in that: The upper end of the plugging lower hydraulic cylinder is screwed with the plugging upper hydraulic cylinder, the inner wall of the lower end piston of the plugging upper hydraulic cylinder is sealed with the outer wall of the plugging upper core shaft, the upper end of the plugging upper core shaft is screwed into the lower end internal thread of the plugging bridge plug upper joint, the upper outer periphery of the plugging upper hydraulic cylinder is suspended on the middle outer periphery of the plugging bridge plug upper joint by pins, an upper hydraulic chamber is provided between the bottom of the plugging bridge plug upper joint and the top of the piston of the plugging upper hydraulic cylinder, an upper core shaft pressure transmission hole is provided on the upper circumference of the plugging upper core shaft, which is connected with the upper hydraulic chamber; a conical trumpet mouth is provided on the inner wall of the plugging lower core shaft below the plugging lower core shaft pressure transmission hole for sealing with a steel ball.

4. The leak plugging and oil production device for a multi-point water-outlet oil well according to claim 2, characterized in that: The drillable intubation oil production bridge plug is sealed above the oil layer and below the water-producing layer. A cannula is inserted into the central production pipe after the release. The outer wall of the cannula is embedded with multiple sealing rings to achieve sealing with the inner wall of the central production pipe. A flow purifier is arranged above the cannula, a telescopic compensator is arranged above the flow purifier, a pump is arranged above the telescopic compensator, and the top of the pump is connected to the tail pipe and supported on the inner wall of the casing by a hydraulic anchor. The telescopic compensator comprises a compensating upper joint, a compensating inner tube, a compensating outer tube and a compensating lower joint. The upper end of the compensating inner tube is screwed into the lower end internal thread of the compensating upper joint, the compensating outer tube is sleeved on the outer circumference of the compensating inner tube, the lower end internal thread of the compensating outer tube is screwed into the upper external thread section of the compensating lower joint, the upper end of the compensating outer tube is provided with a compensating outer tube sealing section with a reduced diameter, the inner wall of the compensating outer tube sealing section is embedded with an outer tube sealing ring to achieve sealing with the compensating inner tube, an outer tube stuffing box is provided above the compensating outer tube sealing section, the outer tube stuffing box is filled with a V-shaped sealing assembly, a parallel ring is screwed into the upper inner thread of the outer tube stuffing box, and the lower end of the parallel ring presses against the V-shaped sealing assembly to tighten it.

5. The leak plugging and oil production device for a multi-point water-outlet oil well according to claim 4 is characterized in that: A gap is provided between the middle section of the compensating inner tube and the compensating outer tube, a compensating inner tube convex ring is provided at the lower end of the compensating inner tube, the compensating inner tube convex ring abuts against the inner wall of the compensating outer tube, the lower end of the compensating inner tube convex ring is evenly provided with an inner tube convex ring lower embedding groove, and the upper end of the compensating lower joint is evenly provided with a compensating lower joint upper embedding groove corresponding to the inner tube convex ring lower embedding groove; The upper end step of the compensation inner tube convex ring is evenly provided with inner tube convex ring upper embedding grooves, and the lower step of the compensation outer tube sealing section is evenly provided with compensation outer tube sealing section lower embedding grooves corresponding to the inner tube convex ring upper embedding grooves.

6. A method for plugging and recovering oil from a multi-point water-outlet oil well, characterized in that: The leak plugging and oil production device for a multi-point water-outlet oil well according to claim 3 comprises the following steps in sequence: S1. Determine that a leaking section appears above the casing cementing section, and a water-producing layer appears in the casing cementing section; S2. Complete the plugging of the leaking section above the casing cementing section; S3, completing the plugging of the water-producing layer in the casing cementing section; S4, producing oil from the adjacent oil layer below the water-producing layer; S5. Continue to produce oil from the next oil layer.

7. The method for plugging and producing oil from a multi-point water-outlet oil well according to claim 6, characterized in that: Step S2 specifically includes the following sub-steps: S2.

1. Deliver the integrated seating and squeezing tool as claimed in claim 1 to the bottom of the leaking section through a pipe string and to the top of the water-producing layer of the cementing section; S2.

2. Pressurize the inside of the pipe string. The upper and lower hydraulic chambers of the seating and squeezing integrated tool build up pressure at the same time to cut the shear nails. Then the upper and lower hydraulic cylinders of the seating and squeezing push tubes are jointly pushed to slide downward. The sealing ring is pressed downward to make the middle section of the long rubber tube of the seating and squeezing bulge outward to achieve the seating and squeezing. The upper and lower slips of the seating and squeezing are anchored on the inner wall of the casing. S2.3, as the wellhead pressure increases, the seating tension ring is pulled off, the seating bridge plug mandrel and the seating sealing mechanism remain in the well, the seating upper joint, seating upper mandrel, seating lower mandrel, seating tension ring, seating upper hydraulic cylinder, seating lower hydraulic cylinder and seating push tube are lifted up along with the pipe string for a distance, and the sealing plug falls down; S2.4, inject water into the well through the central hole of the upper joint, the upper mandrel and the lower mandrel, calculate the water absorption of the leaking section, and then replace a certain amount of mortar. After lifting the pipe string to a safe height, pressurize the wellhead to squeeze the mortar into the leaking section to plug the leak; S2.

5. After the cement slurry is ready to set, the pipe string is pulled out, and the upper joint, upper mandrel, lower mandrel, tension ring, upper hydraulic cylinder, lower hydraulic cylinder and push tube are squeezed out of the wellhead along with the pipe string; S2.

6. Use the lower flat-bottomed grinding shoe to drill through the mortar to the top of the core shaft of the bridge plug, and then test the wellbore pressure to 20MPa. After stabilizing the pressure for 30 minutes, if the pressure drop is less than 0.5MPa, it is judged to be plugging qualified; S2.

7. Lengthen the tubing string and drill directly through the core shaft of the bridge plug to penetrate the wellbore.

8. The method for plugging and producing oil from a multi-point water-outlet oil well according to claim 6, characterized in that: Step S3 specifically includes the following sub-steps: S3.1, in the next trip of the tubing string, lower the drillable bridge plug to the lower part of the adjacent oil layer below the water-producing layer and seal it; S3.2, lower the drillable pipe-inserted oil production bridge plug as claimed in claim 3 to the top of the oil layer 1 and below the water-producing layer; S3.

3. Throw a steel ball into the pipe column, and let it fall to the conical bell mouth of the lower mandrel and seal it; S3.4, the pin is cut off by the pressure at the wellhead, and the upper and lower hydraulic cylinders jointly push the plunger tube downward, the plunger push ring is pressed downward, and the middle section of the plunger long rubber tube bulges outward to achieve sealing; the upper and lower slips of the plunger are anchored on the inner wall of the casing; S3.

5. As the wellhead pressure increases, the plugging shear ring is pulled off and the upper part is released. The plugging center pipe and the plugging sealing mechanism remain in the well. The plugging bridge plug upper joint, plugging upper core shaft, plugging lower core shaft, conversion joint, plugging shear ring, plugging upper hydraulic cylinder, plugging lower hydraulic cylinder and plugging push tube are lifted out of the wellhead along with the pipe string.

9. The method for plugging and producing oil from a multi-point water-outlet oil well according to claim 8, characterized in that: Step S4 specifically includes the following sub-steps: S4.

1. Connect the intubation pipe, the over-current purifier, the telescopic compensator, the oil pump and the hydraulic anchor in sequence at the wellhead and lower them into the well, using the telescopic compensator as described in claim 5, and during the well-entering process, the inner compensating pipe is in the lower limit position; S4.

2. The lower end of the plug is inserted from the plug-in production center pipe of the drillable plug-in production bridge plug. Several sealing rings are embedded on the outer periphery of the plug-in pipe to achieve sealing with the inner wall of the plug-in production center pipe. S4.

3. Wellhead pressure test to verify that the seal between the insertion pipe and the insertion and production center pipe is reliable; S4.

4. Lift the pipe column for a distance to make the telescopic compensator in the middle free compensation position; S4.

5. Pressurize the wellhead to anchor the hydraulic anchor seal on the inner wall of the casing; S4.

6. Start the oil pump to produce oil.

10. The method for plugging and producing oil from a multi-point water-outlet oil well according to claim 9, characterized in that: Step S5 specifically includes the following sub-steps: S5.

1. Drill and grind the pipe string, drill and grind away the drillable pipe production bridge plug, the drillable bridge plug and the gray surface below, and penetrate the wellbore of the oil layer 2 below the oil layer 1; S5.2, in the next trip of the string, lower the new drillable bridge plug below the oil layer 2 and seal it; S5.3, the next trip of tubing string is carried out to lower the new drillable plugged oil production bridge to the top of the oil layer 2 and below the upper adjacent oil layer 1; S5.4, repeat steps S3.3 to S3.5; S5.

5. Repeat steps S4.1 to S4.6.

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