CO2 injection anti-creep packer

Abstract

The present invention discloses a CO2 injection anti-creep seal, which includes a through-tube, wherein the two ends of the through-tube are respectively provided with an upper joint and a lower joint, the ends of the through-tube close to the upper joint and the lower joint are respectively provided with an upper stop cover and a lower stop cover, the outer end of the through-tube close to the upper joint is also sleeved with an upper end cover, the outer end of the through-tube close to the lower joint is sleeved with a lower end cover that cooperates with the upper end cover, a rubber tube is provided between the upper end cover and the lower end cover, and the lower end cover is provided with a locking structure at the cooperation position of the upper end cover and the lower end cover; a sealing ring is provided between the upper end cover and the through-tube, which can slide freely to avoid failure due to creep of the seal; the locking structure is simple, and the sealing and unsealing are convenient; the service life is long, and favorable conditions are provided for stratified water injection or gas injection operations.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas field development and relates to a CO2 injection anti-creeping packer. Background Art

[0002] After a period of development, oilfield formation pressure drops and energy becomes insufficient. Water or gas injection can effectively maintain formation pressure and achieve stable oilfield production. Oilfield water injection is divided into general water injection and stratified water injection. Currently, more and more oilfields are entering the middle and late stages of water injection development. Due to the heterogeneity of the oilfield, general water injection faces a series of development challenges such as water channeling and flooding, resulting in poor oil recovery results. Stratified water or gas injection can adjust interlayer conflicts, improve the sweep coefficient, and effectively prevent water channeling. Packers are a crucial component of stratified water or gas injection.

[0003] Currently, oilfield packers are primarily classified into two types: compression and expansion. During oilfield water injection, temperature and pressure fluctuations can cause severe creep in suspended tubing, leading to up-and-down movement of the packer and friction with the tubing, resulting in failure. To address this issue, an anti-creep packer is urgently needed in stratified water injection. Summary of the Invention

[0004] The purpose of the present invention is to provide a CO2 injection anti-creep packer, which solves the problem of oil well tubing failing due to creep effects caused by pressure and temperature changes.

[0005] The technical solution adopted by the present invention is to inject a CO2 anti-creep seal, which includes a through-tube, with an upper joint and a lower joint provided at both ends of the through-tube respectively, an upper stop cover and a lower stop cover provided at one end of the through-tube close to the upper joint and the lower joint respectively, an upper end cover is also sleeved on the end of the outer side of the through-tube close to the upper joint, and a lower end cover that cooperates with the upper end cover is sleeved on the end of the outer side of the through-tube close to the lower joint, a rubber tube is provided between the upper end cover and the lower end cover, and the lower end cover is provided with a locking structure at the cooperation position between the upper end cover and the lower end cover.

[0006] The present invention is also characterized in that:

[0007] The upper cover and the lower cover are connected to the through-tube by bolts respectively;

[0008] There are two rubber tubes, which are sleeved on the outer sides of the upper end cover in sequence, and are connected by a connector.

[0009] The locking structure includes a pin groove provided on the lower end cover, a pin is embedded in the pin groove, a spring is provided between the pin and the pin groove, the pin groove is located on the inner side of the lower end cover, and the pin points to the upper end cover, and the bottom of the upper end cover is provided with multi-stage locking teeth that cooperate with the pin;

[0010] A plurality of sealing rings are evenly arranged between the upper end cover and the through-tube along the axial direction of the through-tube.

[0011] The beneficial effects of the present invention are:

[0012] The CO2 injection anti-creeping packer of the present invention has the following advantages: (1) The packer has a two-stage sealing rubber tube with good sealing effect; (2) The packer can move freely up and down through the through tube to avoid failure due to creep of the packer; (3) The locking teeth of the packer are simple in structure and are provided with multiple stages of locking teeth, which are suitable for packing operations of different strengths and are convenient for setting and releasing the seal. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic diagram of the CO2 injection anti-creeping packer of the present invention;

[0014] Figure 2 It is a schematic diagram of the locking structure of the CO2 injection anti-creep packer of the present invention.

[0015] In the figure, 1. upper joint, 2. upper baffle, 3. through tube, 4. upper end cover, 5. rubber tube, 6. connecting head, 7. lower end cover, 8. lower joint, 9. lower baffle, 10. locking pin, 11. spring, 12. pin groove, 13. locking tooth, 14. sealing ring, 15. bolt. DETAILED DESCRIPTION

[0016] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0017] The present invention provides a CO2 injection anti-creeping packer, such as Figure 1 As shown, it includes an upper joint 1, an upper baffle 2, a penetrating tube 3, an upper end cover 4, a rubber tube 5, a connecting head 6, a lower end cover 7, a lower joint 8, a lower baffle 9, a locking pin 10, a spring 11, a pin groove 12, a locking tooth 13, a sealing ring 14, and a bolt 15; an upper joint 1 and a lower joint 8 are set at both ends of the penetrating tube 3, an upper baffle 2 is provided at the upper end of the penetrating tube 3, and a lower baffle 9 is provided at the lower end of the penetrating tube 3. The movable distance required for the creep of the pipe string is reserved between the upper baffle 2 and the lower baffle 9, and the piston-like movement can be freely performed under sealing conditions. The upper baffle 2 and the lower baffle 9 are fixed to the penetrating tube 3 by bolts 15. An upper end cover 4 is provided on the outside of the penetrating tube 3, two rubber tubes 5 are set between the upper end cover 4 and the lower end cover 7, and the two rubber tubes 5 are connected by a connecting head 6. The lower end of the rubber tube 5 is connected to the lower end cover 7, as shown Figure 2 As shown, there is a pin groove 12 on the lower end cover 7, a spring 11 and a pin 10 are arranged in the pin groove 12, a locking tooth 13 is arranged at the bottom of the upper end cover 4, and a multi-stage sealing ring 14 is provided between the upper end cover 4 and the through-tube 3;

[0018] Specific operation method: When implementing the sealing operation, the upper and lower ends of the packer are respectively installed on the oil pipe through threads. After lowering to the designed depth, the hydraulic anchor is opened to press the lower end cover 7 of the packer on the hydraulic anchor, and the oil pipe is continued to be pressed down, driving the through tube 3 to move downward, and the upper baffle 2 is seated on the upper end cover 4, and the oil pipe is further pressed down, so that the upper end cover 4 moves downward, compressing the rubber tube 5, and the outer periphery of the rubber tube 5 expands to achieve a seal with the casing. At the same time, the pin 10 is pushed by the spring 11 to engage with the locking tooth 13 below to achieve a locking effect; slightly lift the oil pipe and fix it to start production; during the production process, if the pipe string creeps, the belt The movable through-tube 3 moves up and down, and the packer does not move up and down. There is a sealing ring 14 between the through-tube 3 and the upper end cover 4, and the packer and the casing are sealed by the rubber tube 5, which ensures the sealing effect of the packer and extends the life of the packer. When unsealing, the oil pipe is lifted to drive the through-tube 3 to move up. When the lower baffle 9 at the lower end of the through-tube 3 contacts the lower end of the upper end cover 4, the oil pipe is continued to be lifted. The upper end cover 4 moves upward under the lifting action of the lower baffle 9, and the locking teeth 13 shorten the pins 10, thereby realizing the unsealing of the packer. This packer provides favorable conditions for production operations such as stratified water injection or gas injection in oil fields that are prone to tubing creep.

Claims

1. CO2 injection anti-creep packer, characterized by: The invention comprises a through-tube (3), wherein the two ends of the through-tube (3) are respectively provided with an upper joint (1) and a lower joint (8), and the ends of the through-tube (3) close to the upper joint (1) and the lower joint (8) are respectively provided with an upper stopper (2) and a lower stopper (9), and the end of the through-tube (3) close to the upper joint (1) is also sleeved with an upper end cover (4), and the end of the through-tube (3) close to the lower joint (8) is sleeved with a lower end cover (7) matched with the upper end cover (4), a rubber tube (5) is provided between the upper end cover (4) and the lower end cover (7), and the lower end cover (7) is provided with a locking structure at the matching position of the upper end cover (4) and the lower end cover (7); The locking structure includes a pin groove (12) provided on the lower end cover (7), a pin (10) being embedded in the pin groove (12), a spring (11) being provided between the pin (10) and the pin groove (12), the pin groove (12) being located on the inner side of the lower end cover (7), and the pin (10) pointing toward the upper end cover (4), and a multi-stage locking tooth (13) cooperating with the pin (10) being provided at the bottom of the upper end cover (4); Specific operation method: When implementing the packing operation, the upper and lower ends of the packer are respectively installed on the oil pipe through threads. After lowering to the designed depth, the hydraulic anchor is opened, so that the lower end cover (7) of the packer is pressed on the hydraulic anchor, and the oil pipe is continued to be pressed downward, driving the through tube (3) to move downward, and the upper stop cover (2) is seated on the upper end cover (4), further pressing the oil pipe, so that the upper end cover (4) moves downward, compressing the rubber tube (5), and the outer periphery of the rubber tube (5) expands to achieve a seal between the casing, and at the same time, the pin (10) is driven by the spring (11) to engage with the locking tooth (13) below to achieve a locking effect; slightly lift the oil pipe and fix it to start production; During the production process, when the pipe string creeps, the through-tube (3) is driven to move up and down, but the packer does not move up and down. A sealing ring (14) is provided between the through-tube (3) and the upper end cover (4), and the packer and the casing are sealed by the rubber tube (5), thereby ensuring the sealing effect of the packer and extending the service life of the packer. When unsealing, the oil pipe is lifted to drive the through-tube (3) to move up. When the lower stop cover (9) at the lower end of the through-tube (3) contacts the lower end of the upper end cover (4), the oil pipe is continued to be lifted. The upper end cover (4) moves upward under the lifting action of the lower stop cover (9), and the locking teeth (13) shorten the pins (10), thereby realizing the unsealing of the packer.

2. The CO2 injection anti-creep packer according to claim 1, characterized in that: The upper retaining cover (2) and the lower retaining cover (9) are respectively connected to the through-tube (3) via bolts (15).

3. The CO2 injection anti-creep packer according to claim 1, characterized in that: Two rubber tubes (5) are provided, and the two rubber tubes (5) are sleeved on the outer sides of the upper end cover (4) in sequence. The two rubber tubes (5) are connected via a connector (6).

4. The CO2 injection anti-creep packer according to claim 1, characterized in that: A plurality of sealing rings (14) are evenly arranged between the upper end cover (4) and the through-tube (3) along the axial direction of the through-tube (3).

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