CN217028855U

CN217028855U - Hierarchical control expansion type open hole packer

Info

Publication number: CN217028855U
Application number: CN202123042234.7U
Authority: CN
Inventors: 刘练; 邹伟; 谢进; 李林涛; 李渭亮; 陈丽帆; 赵绍伟; 杨坤; 李琪; 王森; 陈辉; 赵忠辉; 刘军荣
Original assignee: China Petroleum and Chemical Corp; Sinopec Northwest Oil Field Co
Current assignee: China Petroleum and Chemical Corp; Sinopec Northwest Oil Field Co
Priority date: 2021-12-06
Filing date: 2021-12-06
Publication date: 2022-07-22
Anticipated expiration: 2031-12-06

Abstract

The utility model relates to a staged control expansion type open hole packer which comprises a pipe body, wherein a first channel for fluid circulation is defined in the pipe body; the piston comprises an expansion cylinder arranged on the outer wall of the pipe body and a piston cavity arranged on the outer wall of the pipe body and capable of being communicated with the expansion cylinder, wherein the piston cavity is communicated with a first channel through a first through hole arranged on the outer wall of the pipe body, a first piston is arranged in the piston, and the first piston is provided with a first position for initially cutting off the communication between the piston cavity and the expansion cylinder and a second position for keeping the communication between the piston cavity and the expansion cylinder. The staged control expansion type open hole packer can effectively improve the packing reliability of the packer.

Description

Hierarchical control expansion type open hole packer

Technical Field

The utility model relates to a graded control expansion type open hole packer.

Background

The open hole packer is one of the well tools commonly used in the current petroleum production process, and is mainly used for packing different well sections underground so as to perform well completion operation or reservoir transformation operation. The existing packer usually adopts a ball seat setting mode to seal a downhole channel, and a check valve of the packer is controlled by a spring. The device has high requirements on the elasticity of the spring, and when the valve core of the check valve returns, the pressing pressure in the rubber cylinder on the outer wall of the packer can be partially released when the rubber cylinder is set, and the later sealing capacity can be influenced by the process. Meanwhile, such check valves generally need to be opened again after being closed, so as to realize recycling. And in the process that the check valve is opened again, once the rubber sleeve of the expandable open-hole packer is broken, fluid in the pipe can flow out through the check valve, so that the sealing failure of the whole pipe column is caused, and the sealing reliability of the packer is reduced.

SUMMERY OF THE UTILITY MODEL

In view of the technical problems mentioned above, the present invention aims to provide a step-controlled expandable open hole packer. The staged control expansion type open hole packer can effectively improve the packing reliability of the packer.

According to the utility model, a step-control expandable open hole packer is provided, comprising a tubular body, a first passage in fluid communication is defined in the tubular body; the piston comprises an expansion cylinder arranged on the outer wall of the pipe body and a piston cavity arranged on the outer wall of the pipe body and capable of being communicated with the expansion cylinder, wherein the piston cavity is communicated with a first channel through a first through hole arranged on the outer wall of the pipe body, a first piston is arranged in the piston, and the first piston is provided with a first position for initially cutting off the communication between the piston cavity and the expansion cylinder and a second position for keeping the communication between the piston cavity and the expansion cylinder.

In a preferred embodiment, a second piston is also disposed within the piston chamber, the second piston having an initial third position in which the first through-hole remains clear and a fourth position in which the first through-hole is blocked.

In a preferred embodiment, a second through hole which is communicated with the piston cavity and the first channel is arranged on the outer wall of the pipe body at one end, away from the expansion cylinder, of the second piston.

In a preferred embodiment, the first piston and the second piston are fixed in the piston chamber by a first shear pin and a second shear pin, respectively, and the shear force of the second shear pin is set to be larger than that of the first shear pin.

In a preferred embodiment, a step is provided on the inner wall of the piston chamber, so that the piston chamber has a large diameter section and a small diameter section that can be sealed by the first piston, and the first piston can move from the small diameter section into the large diameter section when moving from the first position to the second position.

In a preferred embodiment, a ratchet ring is further provided between the second piston and the outer wall of the tube body, and the second piston is connected to the outer wall of the tube body through the ratchet ring

In a preferred embodiment, a plurality of heat exchange pipes are provided, and a fixing member for preventing the second piston from rotating is further provided between the second piston and the ratchet locking ring.

In a preferred embodiment, a first sealing assembly is further respectively arranged on two radial sides of the first piston close to the tube body and two radial sides of the first piston far away from the tube body, a second sealing assembly is further arranged on the outer wall of the tube body between the first piston and the first through hole, and the first sealing assembly and the second sealing assembly both comprise sealing rings and back rings arranged at two ends of the sealing rings.

In a preferred embodiment, a protective layer is further sleeved on the outer side of the second sealing assembly away from the outer wall of the pipe body, and the protective layer is connected to the first piston.

In a preferred embodiment, the expansion cylinder is made of hydrogenated nitrile material, and the sealing ring and the back ring are made of PEEK material.

Drawings

The present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a schematic representation of a staged control expansion open hole packer according to one embodiment of the utility model.

FIG. 2 is an enlarged view of the square area of the staged control expandable open hole packer 100 shown in FIG. 1.

In the present application, the drawings are all schematic and are used only for illustrating the principles of the utility model and are not drawn to scale.

Detailed Description

The utility model is described below with reference to the accompanying drawings. Hereinafter, the terms "upper end" and "lower end" refer to the end near the wellhead and far from the wellhead, respectively.

FIG. 1 shows a staged control extended open hole packer 100 according to one embodiment of the utility model. As shown in fig. 1, the staged control expandable open hole packer 100 includes a tubular body 10 installed in an oil well. A first passageway 20 is defined in the body 10 for fluid communication. An expansion cylinder 30 is provided on the outer wall of the tubular body 10, which can be expanded to abut against a downhole casing or wall of a well.

As shown in fig. 1, a piston chamber 40 communicating with the expansion cylinder 30 is provided on an outer wall of the tubular body 10 at an upper end of the expansion cylinder 30. Meanwhile, the piston chamber 40 can communicate with the first passage 20 through the first through hole 22 provided on the outer wall of the tube 10. A first piston 41 is disposed in the piston chamber 40, and the first piston 41 is disposed at the lower end of the first through hole 22, so that the high-pressure fluid in the first passage 20 can push the first piston 41 to move toward the lower end of the expansion cylinder 30 after entering the piston chamber 40 through the first through hole 22.

As shown in FIG. 2, during the staged control expanded open hole packer 100 of the present invention run into the well, the first piston 41 is fixed in the piston chamber 40 at an initial first position by a first shear pin 411. When the first piston 41 is in the first position, it is located within the small diameter section 43 of the piston chamber 40. At this time, the first piston 41 can close the piston chamber 40, thereby cutting off the communication between the first through hole 22 and the expansion cylinder 30 and preventing the high-pressure fluid in the first passage 20 from entering the expansion cylinder 30.

When the high-pressure fluid is introduced into the first passage 20, the high-pressure fluid can enter the piston cavity 40 through the first through hole 22, and the first piston 41 is pushed to shear the first shear pin 411. Then, the first piston 40 can move through the step portion 42 under the pushing of the high-pressure fluid until abutting on the sidewall of the lower end of the piston chamber 40. At this time, the first piston 41 reaches inside the large diameter section 44, thereby being at the second position where the piston chamber 40 and the expansion cylinder 30 are kept in communication. In this situation, the first piston 41 cannot close the piston cavity 40 any more, and the high-pressure fluid in the first passage 20 can enter the expansion cylinder 30 through the piston cavity 40, so that the expansion cylinder 30 is sealed to seal the annular space outside the tubular body 10.

As shown in fig. 1, a second piston 45 is further disposed in the piston chamber 40 above the first through hole 22. The outer wall of the tube 10 at the upper end of the second piston 45 is provided with a second through hole 46 communicating with the first channel 20, so that the high-pressure fluid in the first channel 20 can reach the piston cavity 40 at the upper end of the second piston 45 through the second through hole 46.

In the initial state, the second piston 45 is fixed to the piston chamber 45 at the third position by the second shear pin 451, and the second piston 45 is located between the first through hole 22 and the second through hole 45 in the axial direction of the pipe body 10. In this state, the high-pressure fluid in the first passage 20 can simultaneously flow into the piston chamber 40 through the first through hole 22 and the second through hole 45.

When the second shear pin 451 is sheared by the fluid pressure, the second piston 45 can be pushed downward by the fluid until the second piston 45 abuts on the first piston 41. The second piston 45 can now cover the first through-opening 22, thereby cutting off the communication between the first channel 20 and the large-diameter section 44 of the piston chamber 40. At this time, the second piston 45 reaches the fourth position where the communication between the expansion cylinder 30 and the first passage 20 is cut off.

In the present invention, the shearing force of the second shear pin 451 is set to be greater than that of the first shear pin 411, thereby preventing the second shear pin 451 from being sheared prior to the first shear pin 411, and further preventing the first through hole 22 from being closed by the second piston 45 before the expansion cylinder 30 is sealed. Thus, during the operation of the expandable open hole packer 100, an operator can inject high-pressure fluid into the first passage 20 until the first shear pin 411 is sheared, and the fluid enters the expansion cylinder 30 to complete the expansion seal. After the expansion cylinder 30 is fully inflated, the fluid pressure is increased until the second shear pin 451 shears. In this state, the first through hole 22 is closed.

Compared with the existing form of controlling the sealing of the expansion cylinder through the spring, the arrangement of the grading control can prevent the fluid in the expansion cylinder 30 from flowing out after the expansion cylinder 30 is expanded, the sealing integrity of the tubular column is ensured, meanwhile, the influence of the failure of the spring on the open hole packer 100 can be avoided, and the reliability of the open hole packer 100 is improved.

In a preferred embodiment, as shown in fig. 1, a ratchet ring 50 is further provided between the second piston 45 and the outer wall of the housing 10, and the second piston 45 is connected to the outer wall of the housing by the ratchet ring 50. The ratchet ring 50 ensures that the second piston 45 can only move in one direction relative to the barrel 10 (i.e. can only move downwards relative to the barrel 10). With this arrangement, it is possible to prevent the second piston 45 from retreating after closing the first through hole 22, causing the first through hole 22 to be reopened.

Further, a fixing piece 55 is further provided between the second piston 40 and the ratchet lock ring 50, the fixing piece 55 being preferably provided as a socket head cap screw. The second piston 40 can be prevented from rotating in the circumferential direction relative to the ratchet ring 50 by the socket head cap screws without affecting the movement of the second piston 40 relative to the ratchet ring 50 in the axial direction, thereby achieving the effect of fixing the second piston 40.

As shown in fig. 1, a first sealing assembly 60 is further disposed on two radial sides of the first piston 41 close to the tubular body 10 and far from the tubular body 10. The first sealing assembly 60 can seal a slight gap between the first piston 41 and the tubular body 10 and the radial direction of the piston cavity 40, and prevent the fluid in the expansion cylinder 30 from leaking into the first passage 20 through the slight gap after the first through hole 22 is closed, thereby enhancing the sealing performance of the first piston 41.

Meanwhile, a second sealing assembly 62 is disposed on the outer wall of the pipe body 10 between the first piston 41 and the first through hole 22. So that when the second piston 45 reaches the fourth position, it can reach the radially outer side of the second sealing assembly 62 away from the tubular body 10. At this time, the second sealing assembly 62 can close a fine gap between the second piston 45 and the tube 10, thereby achieving a sealing effect.

In the present invention, the first seal assembly 60 and the second seal assembly 62 both include at least one seal ring and at least one backing ring disposed on either side of the seal ring. The sealing performance of the first sealing assembly 60 and the second sealing assembly 62 can be effectively improved by combining the sealing ring and the back ring, so that the reliability of the open hole packer 100 is improved.

As shown in fig. 1, a protective layer 66 is further sleeved on the outer side of the second sealing assembly 62 away from the outer wall of the pipe body 10. The protective layer protects the second seal assembly 62 from corrosion or external forces from the downhole fluid prior to expansion of the expansion cylinder 30. At the same time, the protective layer 60 is fixedly connected to the first piston 41, so that the protective layer 60 can move together with the first piston 41. In this way, during the process of moving the first piston 41 from the first position to the second position, the protective layer 66 can move downward relative to the second sealing assembly 62, so that the second sealing assembly 62 is exposed again, and a sealing effect is achieved.

It should be noted that different sealing elements (not shown) are also disposed at other necessary positions of the staged control expandable open-hole packer 100 (e.g., between the second piston 45 and the piston chamber 40 in the radial direction), and will not be described in detail here.

In addition, in the present invention, the expansion cylinder 30 is made of a hydrogenated nitrile material. The material has better elasticity at high temperature, and can effectively seal irregular well walls in oil wells. Meanwhile, the first and

second seal assemblies

60 and 62 are made of PEEK material. The material has the characteristics of high temperature resistance, high pressure resistance and wear resistance, and can effectively improve the reliability of the first sealing assembly 60 and the second sealing assembly 62.

The operation of the step control expandable open hole packer 100 according to the present invention is briefly described as follows.

The staged control extended open hole packer 100 of the present invention is used to pack different sections downhole. When the oil well is required to be sealed, the open hole packer 100 is firstly lowered to a specified sealing position along with the string. High pressure fluid is then injected downhole, which in turn will flow through first passage 20 and first bore 22 into piston chamber 40, shearing first shear pin 411 and pushing first piston 41 from the initial first position to the second position. At this time, the high-pressure fluid in the first passage 20 may enter the expansion cylinder 30, so that the expansion cylinder 30 is completely sealed.

When the expansion cylinder 30 is fully inflated, the fluid pressure in the first passage 20 is increased, such that the high pressure fluid shears the second shear pin 451 and pushes the second piston 45 from the initial third position to the fourth position. The second piston 45 closes the first through hole 22 at this time, thereby closing the communication between the first passage 20 and the expansion cylinder.

Finally, it should be noted that the above-mentioned embodiments are only preferred embodiments of the present invention, and do not limit the present invention in any way. Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described in the foregoing examples, or that equivalents may be substituted for elements thereof. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a hierarchical control expansion open hole packer which characterized in that includes:

a tubular body (10) defining a first passage (20) in fluid communication therein;

an expansion cylinder (30) disposed on an outer wall of the tubular body, and,

the piston cavity (40) is arranged on the outer wall of the pipe body and can be communicated with the expansion cylinder, the piston cavity is communicated with the first channel through a first through hole (22) formed in the outer wall of the pipe body, a first piston (41) is arranged in the piston, and the first piston is provided with a first position for initially cutting off communication between the piston cavity and the expansion cylinder and a second position for keeping communication between the piston cavity and the expansion cylinder.

2. The staged control expandable open hole packer of claim 1, further comprising a second piston (45) disposed within the piston chamber, the second piston having an initial third position in which the first throughbore remains unobstructed and a fourth position in which the first throughbore can be blocked.

3. The staged control expandable open hole packer of claim 2, wherein a second through hole (46) is provided in the outer wall of the tubular body at an end of the second piston remote from the expansion cylinder to communicate the piston chamber with the first passage.

4. The staged control expansion open hole packer according to claim 3, wherein the first and second pistons are fixed in the piston chamber by first and second shear pins (411, 451), respectively, the shear force of the second shear pin being set to be greater than the shear force of the first shear pin.

5. The staged control expandable open hole packer according to any of claims 1-4, wherein a step (42) is provided on an inner wall of the piston chamber such that the piston chamber has a large diameter section (44) and a small diameter section (43) sealable by the first piston, the first piston being movable from the small diameter section into the large diameter section when moving from the first position to the second position.

6. The staged control expandable open hole packer according to any one of claims 2-4, wherein a ratchet ring (50) is further provided between the second piston and the outer wall of the tubular body, and the second piston is connected to the outer wall of the tubular body by the ratchet ring.

7. The staged control expandable open hole packer according to claim 6, wherein a fastener (55) preventing rotation of the second piston is further provided between the second piston and the ratchet lock ring.

8. The staged control expansion open hole packer according to any one of claims 1-4, wherein a first sealing assembly (60) is further arranged on each radial side of the first piston close to the pipe body and far away from the pipe body, a second sealing assembly (62) is further arranged on the outer wall of the pipe body between the first piston and the first through hole, and each of the first sealing assembly and the second sealing assembly comprises a sealing ring and back rings arranged at two ends of the sealing ring.

9. The staged control expansion open hole packer according to claim 8, wherein a protective layer (66) is further sleeved on the outer side of the second sealing assembly away from the outer wall of the pipe body, and the protective layer is connected to the first piston.

10. The staged control expansion open hole packer according to claim 9, wherein the expansion cylinder is made of hydrogenated nitrile material and the seal ring and the back ring are made of PEEK material.