Hydraulic returnable fishing socket mechanism

Abstract

A hydraulic returnable overshot mechanism is characterized in that an upper connector and a guide shoe are arranged at the two ends of an outer cylinder respectively, a center sleeve, a supporting ring and a plurality of inner clamping teeth are arranged in the outer cylinder, the end of the center sleeve is connected with a channel formed in the upper connector in an inserted mode, and a limiting sleeve and a piston are arranged at the ends, corresponding to the upper connector, of the center sleeve in an embedded mode; the outer wall of the limiting sleeve is attached to the end of the upper connector and the inner wall of the outer cylinder, the piston is arranged in an annular space between the center sleeve and the limiting sleeve, and elastic pieces are arranged in the space among the upper connector, the center sleeve, the limiting sleeve and the piston. The utility model has the beneficial effects that the fish is withdrawn by rotating the tubular column forwards or pressing the tubular column, so that the technical problem that the fish cannot be withdrawn normally in the prior art is solved. Meanwhile, the two modes do not interfere with each other, and the safety of the salvage pipe column is greatly guaranteed. The device can be used for salvaging drill collars, drill rods, oil pipes, joints, couplings and other well pipes, and meets the three principles of salvaging, reversing and retreating.

Description

Technical Field

[0001] The utility model relates to the technical field of oil and gas field well repair and cutting, and more specifically to a hydraulically retractable overshot mechanism. Background Art

[0002] In the prior art, when rotating the overshot tube to retrieve the fallen fish, it is easily affected by dirt or impurities. When withdrawing, the cava is blocked and there are certain restrictions, which can easily lead to a safety hazard that the fallen fish cannot be withdrawn normally. Utility Model Content

[0003] The utility model overcomes the deficiencies in the prior art and provides a hydraulically retractable overshot mechanism.

[0004] The purpose of this utility model is achieved through the following technical solutions.

[0005] A hydraulically retractable salvage tube mechanism comprises: an upper joint and a guide shoe respectively arranged at the two ends of an outer tube, a center sleeve, a support ring and a plurality of inner teeth are provided in the outer tube, the end of the center sleeve can be inserted and connected with the passage provided in the upper joint, a limit sleeve and a piston are nested on the corresponding ends of the center sleeve and the upper joint, the outer wall of the limit sleeve is respectively fitted with the end of the upper joint and the inner wall of the outer tube, the piston is arranged in the annular space between the center sleeve and the limit sleeve, an elastic part is provided in the space between the upper joint, the center sleeve, the limit sleeve and the piston, the piston is clamped with the piston fixed end of the inner tooth, the other end of the inner tooth is limited by the support ring, the support ring is in contact with the end of the guide shoe, an engaging surface is provided on the inner side of the inner tooth, and a plurality of groups of inclined surface structures are provided on the outer wall of the inner tooth, and the outer wall of the inner tooth matches the multi-inclined groove provided on the inner wall of the outer tube.

[0006] The center sleeve includes: a first sleeve, a second sleeve and a third sleeve. The first sleeve, the second sleeve and the third sleeve are arranged in sequence from the corresponding end of the upper joint to the corresponding end of the guide shoe. The first sleeve, the second sleeve and the third sleeve are cylindrical structures with increasing outer diameters. The limit sleeve covers the first sleeve and part of the second sleeve. The piston is nested on the second sleeve. The third sleeve is provided with an internal tooth setting groove. The number and shape of the internal tooth setting groove match the internal tooth.

[0007] An annular groove is provided in the second sleeve, and a sealing ring is provided on the annular groove. The annular groove and the sealing ring match with the piston to form a piston cavity.

[0008] A connecting pipe is provided through the center sleeve, which is respectively connected to the upper joint and the guide shoe. A pressure guide hole is provided on the first sleeve, which is connected to the connecting pipe. The position of the pressure guide hole matches the piston.

[0009] The piston is a circular ring structure, with an annular groove on the inner wall and the outer wall of the piston. A clamping groove is provided on the end of the piston connected to the inner clamping tooth, and the shape and number of the clamping groove match the inner clamping tooth.

[0010] The card slot is a T-shaped card slot.

[0011] The inner clamping tooth includes a first connecting end, a second connecting end and an intermediate clamping part. The first connecting end and the second connecting end are fixedly arranged at both ends of the intermediate clamping part. The first connecting end is clamped with the clamping groove, and the second connecting end is cooperated with the limiting groove set on the support ring. The outer side of the intermediate clamping part is provided with multiple groups of continuous inclined steps, and the inner side of the intermediate clamping part is provided with a bite surface.

[0012] The engaging surface is the reverse thread surface.

[0013] The limiting sleeve is a circular structure, and a step structure is provided on the inner side of the limiting sleeve to limit the piston. An elastic part is provided in the space between the step structure of the limiting sleeve and the center sleeve. A setting groove is provided on the end of the limiting sleeve corresponding to the guide shoe. The shape and number of the setting groove match the clamping structure between the piston and the inner clamping teeth.

[0014] The free end of the guide shoe is provided with a spiral cutout.

[0015] The beneficial effects of the utility model are:

[0016] This solution provides a convenient and retractable cava salvage tube structure as a salvage tool for catching fallen fish from the outer diameter of the fish. It withdraws the fallen fish by rotating the tubing string forward or pressurizing the tubing string, so as to solve the technical problem that the fallen fish cannot be withdrawn normally in the existing technology. At the same time, the above two methods do not interfere with each other, which greatly guarantees the safety of the salvage tubing string. This device can be used to salvage drill collars, drill pipes, oil pipes, joints, couplings and other well pipes, and meets the three principles of being able to salvage, reverse and withdraw. In summary, the device is simple in design, flexible and reliable in operation, has good on-site application effects, and is suitable for promotion and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural diagram of the utility model;

[0018] Figure 2 It is a structural schematic diagram of the longitudinal section of the outer cylinder;

[0019] Figure 3 Schematic diagram of the structure of the cross section of the outer cylinder;

[0020] Figure 4 Schematic diagram of the structure of the center sleeve;

[0021] Figure 5 Schematic diagram of the structure of the limit sleeve;

[0022] Figure 6 Schematic diagram of the structure of the piston;

[0023] Figure 7 Schematic diagram of the structure of the inner tooth;

[0024] Figure 8 Schematic diagram of the structure of the support ring;

[0025] In the figure: 1. upper joint; 2. outer cylinder; 3. elastic member; 4. center sleeve; 41. first sleeve; 42. second sleeve; 43. third sleeve; 44. connecting pipe; 45. pressure guide hole; 46. inner snap-on setting groove; 5. limiting sleeve; 51. setting groove; 6. piston; 61. snap-on groove; 7. inner snap-on; 71. first connecting end; 72. second connecting end; 73. middle clamping part; 74. occlusal surface; 8. support ring; 81. limiting groove; 9. guide shoe. DETAILED DESCRIPTION

[0026] Example

[0027] A hydraulic retractable salvage tube mechanism comprises: an upper joint 1 and a guide shoe 9 respectively arranged at the two ends of an outer tube 2, a center sleeve 4, a support ring 8 and a plurality of internal teeth 7 are provided in the outer tube 2, the end of the center sleeve 4 can be inserted and connected with the passage arranged in the upper joint 1, and a limiting sleeve 5 and a piston 6 are nested on the corresponding ends of the center sleeve 4 and the upper joint 1. The outer wall of the limiting sleeve 5 is respectively fitted with the end of the upper joint 1 and the inner wall of the outer tube 2. The piston 6 is arranged in the annular space between the center sleeve 4 and the limiting sleeve 5. An elastic part 3 is provided in the space between the upper joint 1, the center sleeve 4, the limiting sleeve 5 and the piston 6. The piston 6 is clamped with the fixed end of the piston 6 of the internal teeth 7, and the other end of the internal teeth 7 is limited by the support ring 8. The support ring 8 is in contact with the end of the guide shoe 9. An engaging surface 74 is provided on the inner side of the internal teeth 7, and the outer wall of the internal teeth 7 is provided with multiple groups of inclined surface structures. The outer wall of the internal teeth 7 matches the multi-inclined grooves provided on the inner wall of the outer tube 2.

[0028] The center sleeve 4 includes: a first sleeve 41, a second sleeve 42 and a third sleeve 43. The first sleeve 41, the second sleeve 42 and the third sleeve 43 are arranged in sequence from the corresponding end of the upper joint 1 to the corresponding end of the guide shoe 9. The first sleeve 41, the second sleeve 42 and the third sleeve 43 are cylindrical structures with successively increasing outer diameters. The limiting sleeve 5 covers the first sleeve 41 and part of the second sleeve 42. The piston 6 is nested on the second sleeve 42. The third sleeve 43 is provided with an internal tooth setting groove 46. The number and shape of the internal tooth setting groove 46 match the internal tooth 7.

[0029] An annular groove is provided in the second sleeve body 42 , and a sealing ring is provided on the annular groove. The annular groove and the sealing ring match the piston 6 to form a piston chamber.

[0030] A connecting pipe 44 is provided through the center sleeve 4, which is respectively connected to the upper joint 1 and the guide shoe 9. A pressure guide hole 45 is provided on the first sleeve 41, which is connected to the connecting pipe 44. The position of the pressure guide hole 45 matches the piston 6.

[0031] The piston 6 is a circular ring structure, and an annular groove is provided on the inner wall and the outer wall of the piston 6. A clamping groove 61 is provided on the end of the piston 6 connected to the inner clamping tooth 7. The shape and number of the clamping groove 61 match the inner clamping tooth 7.

[0032] The engaging slot 61 is a T-shaped engaging slot.

[0033] The inner tooth 7 includes a first connecting end 71, a second connecting end 72 and an intermediate clamping portion 73. The first connecting end 71 and the second connecting end 72 are fixedly arranged at both ends of the intermediate clamping portion 73. The first connecting end 71 is clamped with the clamping groove 61, and the second connecting end 72 is cooperated with the limiting groove 81 set on the support ring 8. The outer side of the intermediate clamping portion 73 is provided with multiple groups of continuous inclined steps, and the inner side of the intermediate clamping portion 73 is provided with a bite surface 74.

[0034] The engaging surface 74 is a reverse-threaded salvage thread surface.

[0035] The limiting sleeve 5 is a circular ring structure, and a step structure is provided on the inner side of the limiting sleeve 5 to limit the piston 6. An elastic member 3 is provided in the space between the step structure of the limiting sleeve 5 and the center sleeve 4. A setting groove 51 is provided on the end of the limiting sleeve 5 corresponding to the guide shoe 9. The shape and number of the setting groove 51 match the clamping structure between the piston 6 and the inner clamping tooth 7.

[0036] The free end of the guide shoe 9 is provided with a spiral cutout.

[0037] In this embodiment, the number of the inner teeth 7 is 4, such as Figure 1 As shown, the working principle of the present invention is as follows: the upper joint 1 and the guide shoe 9 are connected to the outer tube 2 through threads, and the center sleeve 4, the limit sleeve 5, the piston 6, the support ring 8 and the inner teeth 7 are arranged on the inner side of the outer tube 2.

[0038] like Figure 2 and Figure 3 As shown, the inner side of the outer cylinder 2 is provided with a groove structure corresponding to the above elements for setting, Figure 3 The number of grooves corresponding to the inner teeth 7 adapted to this embodiment is 4, and they are arranged opposite to each other in pairs.

[0039] like Figure 4As shown, the center sleeve 4 provides support for the limiting sleeve 5, the piston 6 and the inner snap-on teeth 7. The space between the center sleeve 4 and the outer tube 2 is used to set the limiting sleeve 5, the piston 6 and the inner snap-on teeth 7. The end of the first sleeve 41 in the center sleeve 4 and the passage between the upper joint 1 can be inserted and set, which is used for limiting and also for transmitting pressure from the upper joint 1. The pressure enters the connecting pipe 44 through the upper joint 1 and is transmitted to the space between the piston 6 and the center sleeve 4 through the pressure guide hole 45, so as to realize the function of moving the piston by pressing the salvage pipe string, thereby linking the inner snap-on teeth 7 to displace it, thereby releasing the stuck fish. Among them, the second sleeve 42 is provided with an annular groove, and the annular groove is provided with a sealing ring. The sealing ring and the piston 6 form a piston cavity. At the same time, the inner and outer sides of the piston 6 are provided with annular grooves for setting sealing rings for sealing. The third sleeve 43 is provided with an inner snap-on teeth setting groove 46 for allowing the inner snap-on teeth 7 to pass through the third sleeve 43, thereby connecting with the support ring 8.

[0040] like Figure 5 As shown, the limiting sleeve 5 is used to limit the piston 6 and provide a setting space for the elastic member 3. The elastic member 3 adopts a spring and is in a pre-compressed state under normal conditions to provide stress for the piston 6.

[0041] like Figure 6 As shown, the piston 6 is provided with a snap-fit ​​groove 61, which is used to snap-fit ​​with the first connecting end 71 to secure the end. In this embodiment, the snap-fit ​​groove 61 adopts a T-slot structure, and a bevel is milled at the corner of the T-slot to mate with the bevel provided on the first connecting end 71 of the inner tooth 7.

[0042] like Figure 7 As shown, the inner tooth 7 is respectively matched with the clamping groove 61 and the limiting groove 81 through the first connecting end 71 and the second connecting end 72. The second connecting end 72 adopts an inward bevel hook structure to match the limiting groove 81. Figure 8 As shown, the retaining groove 81 is a partially milled-through groove structure, with a rectangular trapezoidal protrusion remaining within the groove. The hypotenuse of the rectangular trapezoidal protrusion matches the angled hook structure of the second connecting end 72, providing a hook connection for fixed position. The outer wall of the intermediate clamping portion 73 is provided with multiple sets of continuous inclined steps, which cooperate with the inner wall of the outer cylinder 2 to limit the position, allowing the internal retaining teeth 7 to move toward the guide shoe 9 within a limited range while simultaneously retracting inward, securing the fish with the engaging surface 74. The engaging surface 74 adopts a reverse-threaded fishing thread structure to enable the fish to be ejected through the forward rotation mechanism.

[0043] Furthermore, when the device is used, the rod-shaped fish is sheathed in the well and the tubing string is lifted. The upper connector 1 drives the outer tube 2 upward. Due to the action of the internal inclined surface of the outer tube 2, the inner teeth 2 are forced to shrink in diameter, biting the fish. When the fish needs to be released, it can be done in two ways.

[0044] 1. Rotate the pipe string forward and use the reverse-threaded fishing thread characteristics of the engaging surface 74 in the inner teeth 7 to rotate the fish forward and remove it.

[0045] 2. Apply pressure to the fishing string. The pressure pushes the piston 6 toward the upper connector 1 through the pressure guide hole 45 on the center sleeve 4. Due to the action of the inner inclined surface of the engaging groove 61 in the piston 6, the inner locking teeth 7 move outward, thereby releasing the fish.

[0046] The device is installed at the bottom of the salvage string and is lowered along with the salvage string. The specific implementation method is as follows:

[0047] 1. Before drilling, calculate the top-impacting square, shoe-milling square and salvage square.

[0048] 2. Connect the overshot tube to the salvage string. Do not clamp the tongs on the tube body to avoid damaging the tube body. The tightening torque should be equal to that of the salvage string.

[0049] 3. Lower the retractable overshot tube to a position 0.3 to 0.5 m away from the top of the fish, start the pump circulation, and flush the sediment around the top of the fish.

[0050] 4. Stop the pump, turn it clockwise intermittently and slowly lower the drill bit to test the fish top.

[0051] 5. According to the changes in the salvage direction and the suspended weight of the salvage drill, when it is determined that the slip has entered the fish top salvage position, stop rotation and apply 3 to 5 tons of drilling pressure to make the fish enter the slip.

[0052] 6. Slowly lift the drill and judge whether the fish has been retrieved based on the change in the hanging weight. If not, repeat the above steps.

[0053] 7. Lift the fish trap 0.5 to 0.8 m from the bottom of the well, brake suddenly 2 to 3 times to prove that the fish trap is firmly stuck and then start drilling normally.

[0054] 8. When the fish top cannot be found when entering the fish top direction, if the length of the salvage drill tool is correctly calibrated, an enlarged guide shoe or wall hook can be added to the retractable salvage tube.

[0055] 9. If you need to withdraw the fish from the well, you can use the rotary withdrawal method. Lower the pipe string to the original hanging weight, rotate the drill string clockwise and slowly lift it up until the retractable overshot tube withdraws the fish.

[0056] 10. If the overshot cannot be withdrawn by rotation, it can be withdrawn by pressure. Lower the pipe string to the original hanging weight position, pressurize the pipe string to 3-5MPa, and then slowly move the pipe string to withdraw the overshot tube and drop the fish.

[0057] The above embodiments of the present invention are described in detail. However, the above contents are only preferred embodiments of the present invention and should not be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A hydraulically retractable overshot mechanism, characterized in that: include: The upper joint and the guide shoe are respectively arranged at the two ends of the outer tube. The outer tube is provided with a center sleeve, a support ring and a plurality of inner teeth. The end of the center sleeve can be inserted and connected with the passage provided in the upper joint. A limit sleeve and a piston are nested on the corresponding ends of the center sleeve and the upper joint. The outer wall of the limit sleeve is respectively fitted with the end of the upper joint and the inner wall of the outer tube. The piston is arranged in the annular space between the center sleeve and the limit sleeve. An elastic part is provided in the space between the upper joint, the center sleeve, the limit sleeve and the piston. The piston is clamped with the piston fixed end of the inner tooth. The other end of the inner tooth is limited by the support ring. The support ring is in contact with the end of the guide shoe. An engaging surface is provided on the inner side of the inner tooth. The outer wall of the inner tooth is provided with multiple groups of inclined surface structures. The outer wall of the inner tooth matches the multi-bevel groove provided on the inner wall of the outer tube.

2. The hydraulic retractable overshot mechanism according to claim 1, characterized in that: The center sleeve includes: a first sleeve, a second sleeve and a third sleeve. The first sleeve, the second sleeve and the third sleeve are arranged in sequence from the corresponding end of the upper joint to the corresponding end of the guide shoe. The first sleeve, the second sleeve and the third sleeve are cylindrical structures with successively increasing outer diameters. The limiting sleeve covers the first sleeve and part of the second sleeve. The piston is nested on the second sleeve. The third sleeve is provided with an internal tooth setting groove. The number and shape of the internal tooth setting groove match the internal tooth.

3. The hydraulic retractable overshot mechanism according to claim 2, characterized in that: An annular groove is provided in the second sleeve, and a sealing ring is provided on the annular groove. The annular groove and the sealing ring match the piston to form a piston chamber.

4. The hydraulically retractable overshot mechanism according to claim 2, characterized in that: The center sleeve is provided with a connecting pipe, which is respectively connected to the upper joint and the guide shoe. The first sleeve is provided with a pressure guide hole, which is connected to the connecting pipe. The position of the pressure guide hole matches the piston.

5. The hydraulically retractable overshot mechanism according to claim 1, characterized in that: The piston is a circular ring structure, and an annular groove is provided on the inner wall and the outer wall of the piston. A sealing ring is provided in the annular groove. A clamping groove is provided on the end of the piston connected to the inner clamping tooth, and the shape and number of the clamping groove match the inner clamping tooth.

6. The hydraulically retractable overshot mechanism according to claim 5, characterized in that: The snap-in slot is a T-shaped slot.

7. The hydraulically retractable overshot mechanism according to claim 5, characterized in that: The inner clamping tooth includes a first connecting end, a second connecting end and an intermediate clamping portion. The first connecting end and the second connecting end are fixedly arranged at both ends of the intermediate clamping portion. The first connecting end is clamped with the clamping groove, and the second connecting end is cooperated with the limiting groove set on the support ring. The outer side of the intermediate clamping portion is provided with multiple groups of continuous inclined steps, and the inner side of the intermediate clamping portion is provided with the engaging surface.

8. The hydraulically retractable overshot mechanism according to claim 7, characterized in that: The engaging surface is a reverse-threaded salvage thread surface.

9. The hydraulically retractable overshot mechanism according to claim 1, characterized in that: The limiting sleeve is a circular ring structure, and a step structure is provided on the inner side of the limiting sleeve to limit the piston. The elastic part is provided in the space between the step structure of the limiting sleeve and the center sleeve. A setting groove is provided on the end of the limiting sleeve corresponding to the guide shoe, and the shape and number of the setting groove match the clamping structure between the piston and the inner clamping teeth.

10. The hydraulically retractable overshot mechanism according to claim 1, characterized in that: A spiral cutout is provided on the free end of the guide shoe.

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