An injection-production integrated process pipe column for a heavy oil well

Abstract

The utility model relates to a kind of injection-production integrated process pipe column for heavy oil well belongs to downhole operation tool technical field of petroleum industry.The utility model discloses hollow anchoring packer and sealing insert tube;The hollow anchoring packer is anchored and sealed in casing, with a center through hole in its inside;The lower end of the sealing insert tube can be inserted into the center through hole of the hollow anchoring packer, and sealing and anchoring connection is formed with the inner wall of the center through hole.The utility model can realize steam injection and oil production alternate operation without lifting main sealing anchoring component, to reduce operation cost, improve production efficiency.

Description

Technical Field

[0001] This utility model belongs to the technical field of downhole operation tools in the petroleum industry, and specifically relates to an integrated injection and production process tubing for heavy oil wells. Background Technology

[0002] Heavy oil is characterized by high viscosity, poor fluidity, and low permeability. To improve oil recovery, unconventional technologies such as steam injection, steam drive, and combustion are often required. These technologies involve high-temperature and high-pressure environments, with wellhead temperatures reaching over 300°C during steam injection, placing extremely high demands on the high-temperature sealing performance of the packers in the well.

[0003] Traditional processes often use thermal packers for gas injection and sealing, but their effective injection time is short, and once the packer fails, the tubing string needs to be pulled up and down again to replace it, resulting in high operating costs. Furthermore, the casing expands due to heat during gas injection, easily leading to casing damage and leakage, accompanied by sand production and other problems, which hinder subsequent oil production. Conventional injection-production operations require multiple tubing pulls, such as lowering the injection tubing, pulling it out, and then lowering the production tubing, wasting significant manpower and resources. Moreover, conventional tools cannot meet the requirement of directly performing oil production operations without moving the tubing string after gas injection. Utility Model Content

[0004] This invention addresses the aforementioned problems and overcomes the shortcomings of existing technologies by providing an integrated injection and production process tubing for heavy oil wells. This invention enables alternating steam injection and oil production operations without the need to remove the main sealing anchoring component, thereby reducing operating costs and improving production efficiency.

[0005] To achieve the above objectives, the present invention adopts the following technical solution.

[0006] This utility model provides an integrated injection and production process string for heavy oil wells, including a hollow anchor packer and a sealing tube; the hollow anchor packer is anchored and sealed inside the casing, and has a central through hole inside; the lower end of the sealing tube can be inserted into the central through hole of the hollow anchor packer, and forms a sealing and anchoring connection with the inner wall of the central through hole.

[0007] Furthermore, the hollow anchor packer includes an outer cylinder, a central tube, a ball seat, a seated piston, a rubber sleeve shaft, a combined sealing rubber sleeve, a cone, slips, and a lower connector; the upper end of the outer cylinder is used to connect to an oil pipe, and the lower end is connected to the lower connector; the central tube is disposed inside the outer cylinder; the ball seat is connected to the lower part inside the central tube, and the seated piston is disposed above the ball seat and located inside the central tube; the rubber sleeve shaft is located below the seated piston and contacts or connects to it; the combined sealing rubber sleeve and the cone are sequentially sleeved outside the central tube, and the lower end face of the rubber sleeve shaft contacts the upper end face of the combined sealing rubber sleeve; the slips are disposed in the conical space between the cone and the lower connector.

[0008] Furthermore, the combined sealing sleeve includes an upper shoulder, a sleeve, and a lower shoulder; the sleeve is disposed between the upper shoulder and the lower shoulder.

[0009] Furthermore, the sealing cannula includes a sliding sealing sleeve, an upper back cap, a pressure ring, an inner combined sealing gasket, a locking sleeve, a straightening sleeve, an outer combined sealing gasket, and a guide sleeve; the upper end of the sliding sealing sleeve is used to connect to an external tubing; the upper back cap and pressure ring are sequentially fitted over the outside of the sliding sealing sleeve, pressing the inner combined sealing gasket onto the sliding sealing sleeve; the locking sleeve and straightening sleeve are connected below the sliding sealing sleeve; the outer combined sealing gasket is fitted over the outside of the straightening sleeve; and the guide sleeve is connected to the bottom end of the straightening sleeve.

[0010] Furthermore, the outer wall of the locking sleeve is provided with a radially protruding locking mechanism, which is used to cooperate with the corresponding groove provided on the inner wall of the rubber sleeve shaft of the hollow anchor packer.

[0011] Furthermore, the outer surface of the outer combined sealing gasket is used to form an interference seal with the inner smooth surface of the rubber sleeve shaft of the hollow anchor packer.

[0012] Furthermore, the sliding sealing sleeve and the inner combined sealing gasket, which is pressed together by the upper back cap and the pressure ring, form an axially sliding sealing pair.

[0013] Furthermore, the maximum outer diameter of the sealing tube is Φ150mm, the working temperature is ≤350℃, the working pressure is ≤21MPa, the anchoring load is 80-100Kn, and it is suitable for sleeves with diameters of Φ159mm-Φ162mm.

[0014] Furthermore, the hollow anchor packer has a maximum outer diameter of Φ150mm, an operating temperature of ≤350℃, an operating pressure of ≤21MPa, an unsealing load of 40-60Kn, and is suitable for sleeves of Φ159mm-Φ162mm.

[0015] The beneficial effects of this utility model.

[0016] The core structural innovation of this utility model is concentrated in the protection: the claims focus on the core innovative components (hollow anchor packer and sealing tube) that realize the "integrated injection and extraction" function and their connection relationship, and the scope of protection is clear and strong.

[0017] Integrated functions and high efficiency: Through the ingenious combination of core components, it achieves rapid and seamless switching between steam injection and oil production functions within the same wellbore, without the need to repeatedly pull up and down the main tubing string, resulting in extremely high operational efficiency.

[0018] Reliable connection, safe and stable: The sealed tube and the hollow anchor packer form a reliable connection through mechanical locking and multiple seals, which can compensate for thermal stress and ensure the integrity of the string under high temperature and high pressure conditions.

[0019] Reusable and economical: The core anchoring and sealing component (hollow anchoring packer) can be permanently left at the bottom of the well for reuse. Only the upper production string (including the sealing tube) needs to be retrieved and replaced, which greatly reduces operating costs. Attached Figure Description

[0020] To make the technical problems solved, the technical solutions, and the beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0021] Figure 1 This is a structural schematic diagram of the well completion configuration of this utility model downhole.

[0022] Figure 2 This is a half-sectional structural diagram of the hollow anchor packer of this utility model.

[0023] Figure 3 This is a half-sectional structural diagram of the sealing cannula of this utility model.

[0024] Figure 4 This is a schematic diagram of the combined sealing rubber tube of the hollow anchor packer of this utility model.

[0025] The markings in the diagram are as follows: 1 is the hollow anchor packer, 2 is the sealing tube, 11 is the outer cylinder, 12 is the central tube, 13 is the ball seat, 14 is the seated piston, 15 is the rubber sleeve shaft, 16 is the combined sealing rubber sleeve, 161 is the upper shoulder, 162 is the rubber sleeve, 163 is the lower shoulder, 17 is the cone, 18 is the slip, 19 is the lower connector, 21 is the sliding sealing sleeve, 22 is the upper back cap, 23 is the pressure ring, 24 is the inner combined sealing gasket, 25 is the locking sleeve, 26 is the straightening sleeve, 27 is the outer combined sealing gasket, and 28 is the guide sleeve. Detailed Implementation

[0026] Combined with appendix Figure 1 As shown, this embodiment provides an integrated injection and production process string for heavy oil wells, the core of which consists of a hollow anchor packer 1 and a sealing insert 2. In the actual wellbore structure, the hollow anchor packer 1 is first lowered and set inside the casing near the production layer. Subsequently, the sealing insert 2 is connected to the lowermost end of the production string, which consists of a gas-tight tubing and a rod pump outer working cylinder, and lowered into the well and inserted into the hollow anchor packer 1.

[0027] Combined with appendix Figure 2 As shown, the specific structure of the hollow anchor packer 1 is as follows: The upper end of the outer cylinder 11 is connected to an oil pipe, and the lower end is threadedly connected to the lower connector 19. The central tube 12 is placed inside the outer cylinder 11. The ball seat 13 is fixed in the lower channel inside the central tube 12 by a pin or thread, and the seated piston 14 is located above it. The rubber sleeve shaft 15 rests on the lower end of the seated piston 14. The combined sealing rubber sleeve 16 and the cone 17 are sequentially sleeved on the outside of the central tube 12, and the lower end of the rubber sleeve shaft 15 directly presses against the upper shoulder of the combined sealing rubber sleeve 16. The slip 18 sits on the conical surface of the lower connector 19 and is covered from above by the cone 17.

[0028] During setting, pressure is applied to the tubing, pushing the setting piston 14, rubber sleeve shaft 15, and cone 17 downwards together. Cone 17 forces slips 18 to radially expand and anchor the casing, while rubber sleeve shaft 15 compresses the combined sealing rubber sleeve 16, sealing the casing. After setting, the original tubing string is removed, leaving only the combined sealing rubber sleeve 16, slips 18, and cone 17 components in the well.

[0029] Combined with appendix Figure 4 As shown, the combined sealing rubber cylinder 16 is an integral component composed of a metal shoulder and a rubber cylinder. The upper shoulder 161 and the lower shoulder 163 clamp and protect the middle rubber cylinder 162. When the tool is subjected to the upper and lower pressure difference, it provides support for the rubber cylinder 162, so that the hollow anchor packer 1 can withstand the bidirectional pressure difference.

[0030] The technical parameters of the hollow anchor packer 1 are as follows: maximum outer diameter of the tool Φ150mm, working temperature ≤350℃, working pressure ≤21MPa, unsealing load 40-60Kn, and applicable sleeve Φ159mm-Φ162mm.

[0031] Combined with appendix Figure 3As shown, the specific structure of the sealing tube 2 is as follows: The upper end of the sliding sealing sleeve 21 has threads for connecting to the gas-tight oil pipe. The upper back cap 22 and the pressure ring 23 press the inner combined sealing gasket 24 onto the shoulder of the sliding sealing sleeve 21. The locking sleeve 25 and the straightening sleeve 26 are connected to the lower part of the sliding sealing sleeve 21 by threads. The outer combined sealing gasket 27 is installed in the annular groove in the middle of the straightening sleeve 26. The guide sleeve 28 is connected to the bottom end of the straightening sleeve 26 by threads.

[0032] The technical parameters of the sealing cannula 2 are as follows: maximum outer diameter of the tool Φ150mm, working temperature ≤350℃, working pressure ≤21MPa, anchoring load 80-100Kn, applicable sleeve: Φ159mm-Φ162mm.

[0033] When the production tubing is lowered, the sealing tube 2, guided by the guide sleeve 28, is inserted into the central through-hole of the hollow anchor packer 1 in the well. After insertion, the boss on the locking sleeve 25 engages with the groove on the inner wall of the rubber sleeve shaft 15 to achieve locking. At the same time, the outer combined sealing gasket 27 on the straightening sleeve 26 is tightly fitted with the smooth inner surface of the rubber sleeve shaft 15 to form a high-pressure seal. During steam injection, the tubing expands due to heat, and the sliding sealing sleeve 21 can slide downward relative to the compressed inner combined sealing gasket 24, thereby absorbing the expansion and preventing seal failure or tubing bending.

[0034] When oil production is required, the sucker rod and the inner working barrel of the rod pump are directly lowered into the outer working barrel of the rod pump to start pumping. When pump inspection or maintenance is required, simply lift the production tubing string and remove the sealing insert 2, while the hollow anchor packer 1 remains at the bottom of the well and can be reused.

[0035] It is understood that the above specific description of this utility model is only used to illustrate this utility model and is not limited to the technical solutions described in the embodiments of this utility model. Those skilled in the art should understand that modifications or equivalent substitutions can still be made to this utility model to achieve the same technical effect; as long as the use needs are met, they are all within the protection scope of this utility model.

Claims

1. A production-injection integrated tubing string for heavy oil wells, characterized in that, Hollow anchor packer (1) and sealing tube (2); the hollow anchor packer (1) is anchored and sealed inside the sleeve, and has a central through hole inside; the lower end of the sealing tube (2) can be inserted into the central through hole of the hollow anchor packer (1) and form a sealing and anchoring connection with the inner wall of the central through hole.

2. The integrated injection and production process tubing for heavy oil wells according to claim 1, characterized in that, The hollow anchor packer (1) includes an outer cylinder (11), a central tube (12), a ball seat (13), a seated piston (14), a rubber sleeve shaft (15), a combined sealing rubber sleeve (16), a cone (17), slips (18), and a lower connector (19); the upper end of the outer cylinder (11) is used to connect to an oil pipe, and the lower end is connected to the lower connector (19); the central tube (12) is located inside the outer cylinder (11); the ball seat (13) is connected to the lower part inside the central tube (12), and the seated piston (14)... The plug (14) is positioned above the ball seat (13) and inside the central tube (12); the rubber sleeve shaft (15) is positioned below the seated piston (14) and contacts or connects to it; the combined sealing rubber sleeve (16) and the cone (17) are sequentially sleeved outside the central tube (12), and the lower end face of the rubber sleeve shaft (15) contacts the upper end face of the combined sealing rubber sleeve (16); the slip (18) is positioned in the conical space between the cone (17) and the lower connector (19).

3. The injection-production integrated tubing string for heavy oil wells according to claim 2, characterized in that, The combined sealing sleeve (16) includes an upper shoulder (161), a sleeve (162) and a lower shoulder (163); the sleeve (162) is disposed between the upper shoulder (161) and the lower shoulder (163).

4. The injection-production integrated tubing string for heavy oil wells according to claim 2, characterized in that, The sealing cannula (2) includes a sliding sealing sleeve (21), an upper back cap (22), a pressure ring (23), an inner combined sealing gasket (24), a locking sleeve (25), a straightening sleeve (26), an outer combined sealing gasket (27), and a guide sleeve (28). The upper end of the sliding sealing sleeve (21) is used to connect to an external tubing. The upper back cap (22) and the pressure ring (23) are sequentially fitted onto the outside of the sliding sealing sleeve (21) and press the inner combined sealing gasket (24) onto the sliding sealing sleeve (21). The locking sleeve (25) and the straightening sleeve (26) are connected below the sliding sealing sleeve (21). The outer combined sealing gasket (27) is fitted onto the outside of the straightening sleeve (26). The guide sleeve (28) is connected to the bottom end of the straightening sleeve (26).

5. The injection-production integrated tubing string for heavy oil wells according to claim 4, characterized in that, The outer wall of the locking sleeve (25) is provided with a radially protruding locking mechanism, which is used to cooperate with the corresponding groove provided on the inner wall of the rubber tube shaft (15) of the hollow anchor packer (1).

6. The injection-production integrated tubing string for heavy oil wells according to claim 4, characterized in that, The outer surface of the outer combined sealing gasket (27) is used to form an interference seal with the inner smooth surface of the rubber sleeve shaft (15) of the hollow anchor packer (1).

7. The injection-production integrated tubing string for heavy oil wells according to claim 4, characterized in that, The sliding sealing sleeve (21) and the inner combined sealing gasket (24) pressed by the upper back cap (22) and the pressure ring (23) form an axially sliding sealing pair.

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