A packer

Abstract

A packer relates to the field of oilfield downhole tool technology. An upper connector is connected to a central tube via a suspension pin. The lower part of the central tube is connected to a lower connector via threads and a sealing ring. On the outside of the central tube, from top to bottom, are sequentially fitted an upper compression spring, an upper limit ring, an upper rubber sleeve, a spacer ring, a lower rubber sleeve, a lower limit ring, and a lower compression spring. The upper end of the upper compression spring rests against the bottom of the upper connector, and the lower end of the lower compression spring abuts against the lower connector. The beneficial effects of this invention are: during installation, the upper and lower limit rings store energy in the upper and lower compression springs. After the packer is inserted into the well, the upper and lower limit pins dissolve upon contact with the downhole fluid, completing the setting seal without requiring bottomhole pressure limitations; setting can be achieved even if there is no fluid pressure at the packer installation location.

Description

Technical Field

[0001] This utility model relates to the field of oilfield downhole tools technology, and in particular to a packer. Background Technology

[0002] Packers are commonly used downhole tools in oilfield development to complete various downhole processes such as oil production, water injection, and well washing. Conventional packers mostly use hydraulic setting or mechanical lifting and rotation to set and release the packer, requiring additional pump trucks, tank trucks, and manual operation support. If the packer is installed at the lower end of the pumping unit, the liquid pressure cannot be transmitted to the packer's inner cavity, and the packer cannot achieve pressure-locking and setting, causing problems for oilfield production. Utility Model Content

[0003] To address the aforementioned problems, this utility model provides a packer.

[0004] The technical solution provided by this utility model is: a packer, including an upper connector and a lower connector. The upper part of the upper connector is machined with a female thread for an oil pipe. The lower part of the upper connector is connected to the central tube through a sealing ring with a clearance fit. The upper connector is connected to the central tube through a suspension pin. The lower part of the central tube is connected to the lower connector through a thread and a sealing ring. On the outside of the central tube, from top to bottom, an upper compression spring, an upper limit ring, an upper rubber sleeve, a spacer ring, a lower rubber sleeve, a lower limit ring, and a lower compression spring are sequentially fitted. The upper end of the upper compression spring rests against the bottom of the upper connector, and the lower end of the lower compression spring rests against the lower connector.

[0005] The upper limit ring is connected to the central tube via an upper limit pin. A countersunk hole is opened on the inner side of the upper limit ring. An upper limit hole is opened on the central tube at the upper limit ring position. The upper limit pin is inserted from the inner side of the central tube into the upper limit hole and extends into the countersunk hole of the upper limit ring. The lower limit ring is connected to the central tube via a lower limit pin. A countersunk hole is opened on the inner side of the lower limit ring. A lower limit hole is opened on the central tube at the lower limit ring position. The lower limit pin is inserted from the inner side of the central tube into the lower limit hole and extends into the countersunk hole of the lower limit ring.

[0006] Both the upper and lower limit pins are made of soluble metal. During installation, the upper and lower compression springs are in the maximum compressed state, and the upper and lower rubber sleeves are not subjected to axial force.

[0007] The upper connector has a hanging groove in the inner hole that connects to the central tube. The hanging groove is arranged in a strip shape. The central tube has a hanging hole in the hanging groove. The hanging pin is connected to the hanging hole with an interference fit. The hanging pin is inserted into the hanging groove. A release pin is machined on the outside of the hanging pin. A release hole is opened at the bottom of the hanging groove. The release hole is located at the upper part of the hanging groove. The release pin is inserted into the release hole.

[0008] An upper piston is sandwiched between the upper compression spring and the upper limit ring. The upper piston is sleeved on the outside of the central tube. Two sealing rings are set on one side of the central tube on the upper piston. When the packer is set, the two sealing rings of the upper piston cover the upper and lower sides of the upper limit hole.

[0009] A lower piston is sandwiched between the lower compression spring and the lower limit ring. The lower piston is sleeved on the outside of the central tube. Two sealing rings are set on one side of the central tube for the lower piston. When the packer is set, the two sealing rings of the lower piston cover the upper and lower sides of the lower limit hole.

[0010] A ball seat sleeve is installed in the inner hole of the lower connector. The ball seat sleeve is connected to the lower connector through a lower fixing pin and a sealing ring. The ball seat sleeve is made of soluble metal.

[0011] Several axially penetrating grooves are opened on the outer circles of the upper limit pin and the lower limit pin, and the grooves are evenly arranged along the outer circles of the upper limit pin and the lower limit pin.

[0012] The outer circle of the upper connector is connected to the upper outer sleeve through the upper fixing pin. The upper outer sleeve extends downward to the upper piston part, and the upper outer sleeve and the upper piston are fitted with a clearance.

[0013] The lower connector's outer circle is connected to the lower outer sleeve via a central fixing pin. The lower outer sleeve extends upwards to the lower piston, and the lower outer sleeve and the lower piston are fitted with a clearance fit.

[0014] The beneficial effects of this utility model are as follows: During installation, the upper and lower limit rings store energy for the upper and lower compression springs. After the packer enters the well, the upper and lower limit pins dissolve upon contact with the downhole fluid, thus completing the setting seal. This eliminates the need for bottomhole pressure restrictions. If there is no downhole fluid to dissolve the limit pins, a soluble ball is inserted into the tubing string. The soluble ball lands on the ball seat sleeve and seals. The dissolving liquid is then injected into the tubing string, causing the limit pins to dissolve and the packer to set. Unsealing is simple and reliable. Attached Figure Description

[0015] Appendix Figure 1 This is a schematic diagram of the structure of this utility model;

[0016] Appendix Figure 2 This is a schematic diagram of the upper connector;

[0017] Appendix Figure 3 This is a schematic diagram of the central tube structure;

[0018] Appendix Figure 4 This is a structural diagram of the upper limit pin.

[0019] Appendix Figure 5 This is a schematic diagram of the sealing structure of this utility model;

[0020] Appendix Figure 6 This is a schematic diagram of the unsealing structure of this utility model.

[0021] In the diagram, 1-upper connector, 101-oil pipe female thread, 102-suspension groove, 103-unsealing hole, 2-center tube, 201-suspension hole, 202-upper limit hole, 203-lower limit hole, 3-lower connector, 4-lower outer sleeve, 5-lower limit ring, 6-lower rubber sleeve, 7-spacer ring, 8-upper rubber sleeve, 9-upper limit ring, 10-upper outer sleeve, 11-upper compression spring, 12-upper piston, 13-upper limit pin, 131-groove, 14-lower limit pin, 15-lower piston, 16-lower compression spring, 17-ball seat sleeve, 18-suspension pin, 181-unsealing pin, 19-upper fixing pin, 20-middle fixing pin, 21-lower fixing pin. Detailed Implementation

[0022] like Figures 1-6 As shown, a packer includes an upper connector 1 and a lower connector 3. The upper part of the upper connector 1 is machined with an oil pipe female thread 101. The lower part of the upper connector 1 is connected to the central tube 2 through a sealing ring clearance fit. The upper connector 1 is connected to the central tube 2 through a suspension pin 18. The lower part of the central tube 2 is connected to the lower connector 3 through threads and a sealing ring. On the outside of the central tube 2, from top to bottom, an upper compression spring 11, an upper limit ring 9, an upper rubber sleeve 8, a spacer ring 7, a lower rubber sleeve 6, a lower limit ring 5, and a lower compression spring 16 are sequentially fitted. The upper end of the upper compression spring 11 rests against the bottom of the upper connector 1, and the lower end of the lower compression spring 16 abuts against the lower connector 3.

[0023] The upper limit ring 9 is connected to the central tube 2 via the upper limit pin 13. The upper limit ring 9 has a countersunk hole on its inner side. The central tube 2 has an upper limit hole 202 at the upper limit ring 9. The upper limit pin 13 is inserted from the inner side of the central tube 2 into the upper limit hole 202 and extends into the countersunk hole of the upper limit ring 9. The lower limit ring 5 is connected to the central tube 2 via the lower limit pin 14. The lower limit ring 5 has a countersunk hole on its inner side. The central tube 2 has a lower limit hole 203 at the lower limit ring 5. The lower limit pin 14 is inserted from the inner side of the central tube 2 into the lower limit hole 203 and extends into the countersunk hole of the lower limit ring 5.

[0024] Both the upper limit pin 13 and the lower limit pin 14 are made of soluble metal. During installation, the upper compression spring 11 and the lower compression spring 16 are in the maximum compressed state, and the upper rubber sleeve 8 and the lower rubber sleeve 6 are not subjected to axial force.

[0025] The upper connector 1 has a hanging groove 102 in the inner hole connected to the central tube 2. The hanging groove 102 is arranged in a strip shape from top to bottom. The central tube 2 has a hanging hole 201 in the hanging groove 102. The hanging pin 18 is connected to the hanging hole 201 with an interference fit. The hanging pin 18 is inserted into the hanging groove 102. The outer side of the hanging pin 18 is machined with a release pin 181. The bottom of the hanging groove 102 has a release hole 103. The release hole 103 is located at the upper part of the hanging groove 102. The release pin 181 is inserted into the release hole 103.

[0026] After the packer is inserted into the well, it begins to come into contact with the well fluid and undergoes a chemical reaction, slowly dissolving. After a preset time, the upper limit pin 13 and the lower limit pin 14 completely dissolve, and the upper compression spring 11 and the lower compression spring 16 compress the upper rubber sleeve 8 and the lower rubber sleeve 6 to expand outward and set the packer.

[0027] This invention stores energy in the upper compression spring 11 and lower compression spring 16 via the upper limit ring 9 and lower limit ring 5 during installation. After the packer is inserted into the well, the upper limit pin 13 and lower limit pin 14 dissolve upon contact with the downhole fluid, thus completing the setting seal without the need for bottomhole pressure limitation.

[0028] When the packer is unsealed, the tube column is lifted, the unsealing pin 181 is cut off, the suspension pin 18 descends along the suspension groove 102, that is, the central tube 2 descends a distance relative to the upper connector 1, the pressure of the upper compression spring 11 and the lower compression spring 16 is released, the upper rubber sleeve 8 and the lower rubber sleeve 6 retract under their own elasticity, and the packer is unsealed.

[0029] An upper piston 12 is sandwiched between the upper compression spring 11 and the upper limit ring 9. The upper piston 12 is sleeved on the outside of the central tube 2. Two sealing rings are provided on one side of the central tube 2 on the upper piston 12. When the packer is set, the two sealing rings of the upper piston 12 cover the upper and lower sides of the upper limit hole 202.

[0030] A lower piston 15 is sandwiched between the lower compression spring 16 and the lower limit ring 5. The lower piston 15 is sleeved on the outside of the central tube 2. Two sealing rings are provided on one side of the central tube 2 on the lower piston 15. When the packer is set, the two sealing rings of the lower piston 15 cover the upper and lower sides of the lower limit hole 203. The purpose of this technical solution is to prevent leakage in the central tube 2 at the upper limit hole 202 and the lower limit hole 203 after the packer is set.

[0031] The inner hole of the lower connector 3 is fitted with a ball seat sleeve 17. The ball seat sleeve 17 is connected to the lower connector 3 through the lower fixing pin 21 and the sealing ring. The ball seat sleeve 17 is made of soluble metal. When the packer is installed at a shallow position and there is no liquid downhole to dissolve the limiting pin, a soluble ball is dropped into the tubing. The soluble ball lands on the ball seat sleeve 17 and seals, sealing the lower part of the packer. A dissolving liquid is injected into the tubing to dissolve the limiting pin and set the packer.

[0032] Several axially penetrating grooves 131 are opened on the outer circles of the upper limit pin 13 and the lower limit pin 14. The grooves 131 are evenly arranged along the outer circles of the upper limit pin 13 and the lower limit pin 14. The grooves 131 facilitate the flow of downhole fluid, so that the upper limit pin 13 and the lower limit pin 14 are uniformly dissolved as a whole.

[0033] The outer circle of the upper connector 1 is connected to the upper outer sleeve 10 through the upper fixing pin 19. The upper outer sleeve 10 extends downward to the upper piston 12, and the upper outer sleeve 10 and the upper piston 12 are in clearance fit.

[0034] The outer circle of the lower connector 3 is connected to the lower outer sleeve 4 through the middle fixing pin 20. The lower outer sleeve 4 extends upward to the lower piston 15. The lower outer sleeve 4 and the lower piston 15 are in clearance fit. The function of this section is to prevent downhole fluid from entering (or a small amount) the upper compression spring 11 and the lower compression spring 16, to prevent them from rusting, and to maintain their elasticity, that is, the setting force of the packer.

Claims

1. A packer, comprising an upper connector (1) and a lower connector (3), characterized in that: The upper connector (1) is machined with a female thread (101) for the oil pipe. The lower part of the upper connector (1) is connected to the central tube (2) through a gap fit of the sealing ring. The upper connector (1) is connected to the central tube (2) through a suspension pin (18). The lower part of the central tube (2) is connected to the lower connector (3) through threads and a sealing ring. On the outside of the central tube (2), from top to bottom, there are an upper compression spring (11), an upper limit ring (9), an upper rubber sleeve (8), a spacer ring (7), a lower rubber sleeve (6), a lower limit ring (5), and a lower compression spring (16). The upper end of the upper compression spring (11) is against the bottom of the upper connector (1), and the lower end of the lower compression spring (16) is against the lower connector (3). The upper limit ring (9) is connected to the central tube (2) through the upper limit pin (13). The upper limit ring (9) has a countersunk hole on its inner side. The central tube (2) has an upper limit hole (202) at the upper limit ring (9). The upper limit pin (13) is inserted into the upper limit hole (202) from the inner side of the central tube (2) and extends into the countersunk hole of the upper limit ring (9). The lower limit ring (5) is connected to the central tube (2) through the lower limit pin (14). The lower limit ring (5) has a countersunk hole on its inner side. The central tube (2) has a lower limit hole (203) at the lower limit ring (5). The lower limit pin (14) is inserted into the lower limit hole (203) from the inner side of the central tube (2) and extends into the countersunk hole of the lower limit ring (5). The upper limit pin (13) and the lower limit pin (14) are both made of soluble metal. During installation, the upper compression spring (11) and the lower compression spring (16) are in the maximum compressed state, and the upper rubber sleeve (8) and the lower rubber sleeve (6) are not subjected to axial force.

2. A packer according to claim 1, characterized in that: The upper connector (1) has a hanging groove (102) in the inner hole connected to the central tube (2). The hanging groove (102) is arranged in a strip shape. The central tube (2) has a hanging hole (201) in the hanging groove (102). The hanging pin (18) is connected to the hanging hole (201) with an interference fit. The hanging pin (18) is inserted into the hanging groove (102). The outer side of the hanging pin (18) is machined with a release pin (181). The bottom of the hanging groove (102) has a release hole (103). The release hole (103) is located at the upper part of the hanging groove (102). The release pin (181) is inserted into the release hole (103).

3. A packer according to claim 1, characterized in that: An upper piston (12) is sandwiched between the upper compression spring (11) and the upper limit ring (9). The upper piston (12) is sleeved on the outside of the central tube (2). The upper piston (12) is provided with two sealing rings on one side of the central tube (2). When the packer is set, the two sealing rings of the upper piston (12) cover the upper and lower sides of the upper limit hole (202). A lower piston (15) is sandwiched between the lower compression spring (16) and the lower limit ring (5). The lower piston (15) is sleeved on the outside of the central tube (2). Two sealing rings are provided on one side of the central tube (2) of the lower piston (15). When the packer is set, the two sealing rings of the lower piston (15) cover the upper and lower sides of the lower limit hole (203).

4. A packer according to claim 1, characterized in that: A ball seat sleeve (17) is installed in the inner hole of the lower connector (3). The ball seat sleeve (17) is connected to the lower connector (3) through a lower fixing pin (21) and a sealing ring. The ball seat sleeve (17) is made of soluble metal.

5. A packer according to claim 1, characterized in that: Several axially penetrating grooves (131) are opened on the outer circles of the upper limit pin (13) and the lower limit pin (14), and the grooves (131) are evenly arranged along the outer circles of the upper limit pin (13) and the lower limit pin (14).

6. A packer according to claim 1, characterized in that: The outer circle of the upper connector (1) is connected to the upper outer sleeve (10) by the upper fixing pin (19). The upper outer sleeve (10) extends downward to the upper piston (12) and the upper outer sleeve (10) and the upper piston (12) are in clearance fit. The outer circle of the lower connector (3) is connected to the lower outer sleeve (4) through the middle fixing pin (20). The lower outer sleeve (4) extends upward to the lower piston (15) and the lower outer sleeve (4) and the lower piston (15) are in clearance fit.

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