Self-adaptive high-pressure sealing oil well annular blowout preventer

Abstract

The invention provides a self-adaptive high-pressure sealing oil well annular blowout preventer, and relates to the technical field of oilfield exploitation equipment. The device comprises a central control unit, a hydraulic execution unit and an annular blowout preventer, the annular blowout preventer comprises a pipe main body shell and a cover body, a conical rubber core is arranged above a piston in the cover body, a lubricating liquid injection one-way valve is arranged on the cover body, and a pressing piece sensor is arranged between the cover body and the top of the conical rubber core. The high-frequency hydraulic reversing valve control unit loop is added to an original hydraulic execution unit loop in parallel, the high-frequency hydraulic reversing valve control unit loop controls a piston to vibrate up and down in a high-frequency mode when a drill column is forcibly lifted, abrasion to a conical rubber core when the drilling tool pipe column is forcibly lifted can be greatly reduced, the efficiency of lifting the drilling tool pipe column is improved, and the service life of the drilling tool pipe column is prolonged. The vigorous popularization is worthy.

Description

Technical Field

[0001] This invention relates to the field of oilfield extraction equipment technology, specifically to an adaptive high-pressure sealing annular blowout preventer for oil wells. Background Technology

[0002] Annular blowout preventers (BOPs) are typically used in conjunction with gate-type BOPs. When activated, they create a sealed annular space between the tubing string and the wellbore, allowing for well sealing even when no tubing string is present. An annular BOP contains a rubber core that seals the annular space between the tubing string and the wellhead when the tubing string is present, or completely seals the wellhead when the well is empty. In the initial stages of blowout control without well pressure, annular BOPs often require forced tripping of the tubing string, which causes severe wear on the rubber core. The pressure on the rubber core increases significantly when the drill string joint passes through it, shortening its lifespan. To extend the lifespan of the rubber core, current technology limits the tripping speed to no more than 2 meters per second and imposes strict dimensional requirements on the joints used for tripping the tubing string. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides an adaptive high-pressure sealing annular blowout preventer for oil wells, which solves the problems of severe wear of the rubber core and low efficiency of tripping drill strings during forced tripping.

[0004] To achieve the above objectives, the present invention provides the following technical solution: an adaptive high-pressure sealing well annular blowout preventer, comprising a central control unit, a hydraulic control unit, and an annular blowout preventer. The annular blowout preventer includes: an annular blowout preventer body, a support cylinder, a piston, a starting oil line, a conical rubber core, and a closing oil line; a cover, wherein a pressure sensor is installed between the cover and the top surface of the conical rubber core block; a high-frequency hydraulic directional valve control unit circuit is connected in parallel to the control circuit of the hydraulic control unit; the central control unit is electrically connected to a conversion module, and the conversion module is electrically connected to both the hydraulic control unit and the high-frequency hydraulic directional valve control unit.

[0005] Preferably, the conical core is composed of conical core blocks arranged circumferentially, with gaps between the conical core blocks.

[0006] Preferably, a lubricating fluid injection check valve is provided in the cavity between the cover and the shoulder surface of the conical rubber core block.

[0007] Preferably, the conical rubber core is provided with elastic reinforcing ribs inside, and the rubber core block of the conical rubber core and the reinforcing ribs are integrally formed.

[0008] Preferably, the tablet pressure sensor is electrically connected to the central control unit via a control line.

[0009] An operating method for an adaptive high-pressure sealing ring blowout preventer for oil wells, characterized by: Step 1, conventional operation as in existing technology: When a blowout occurs, the operator sends a signal to the conversion module via the central control unit to select the hydraulic control unit circuit for operation. The operator observes the pressure signal from the pressure sensor reaching the sealing working pressure. At this time, the piston rises to open the sealing working state between the conical rubber core and the drill string; Step 2, when tripping the drill string, the operator injects lubricating fluid into the cavity between the cover and the shoulder of the conical rubber core block through the lubricating fluid injection check valve. The operator sends a signal to the conversion module via the central control unit to select the high-frequency hydraulic directional valve control unit for operation, closing the hydraulic control unit circuit. At this time, the piston oscillates at high frequency in the sealed state; Step 3, when tripping the drill string is completed, or after blowout control, when it is necessary to release the sealing state between the conical rubber core and the drill string, the operator sends a signal to the conversion module via the central control unit to select the hydraulic control unit circuit for operation, closing the valve control unit circuit, restoring the conventional operation as in existing technology.

[0010] This invention provides an adaptive high-pressure sealing annular blowout preventer for oil wells. It has the following beneficial effects:

[0011] 1. This invention adds a high-frequency hydraulic reversing valve control unit circuit, which can control the piston to vibrate up and down at high frequency when the drill string is forcibly pulled up or down. This allows for a working mode with a movable clearance between the conical rubber core and the drill string, which can greatly reduce the wear on the conical rubber core caused by the drill string during forced pulling up or down, and at the same time increase the speed of pulling up or down the drill string.

[0012] 2. This invention injects lubricating fluid into the space between the cover and the top surface of the conical rubber core block through a one-way lubricating fluid injection valve. Then, when the drill string is forcibly pulled up or down, the lubricating fluid passes through the gap of the conical rubber core block onto the drill string, thereby playing a lubricating role. This greatly reduces the wear on the conical rubber core block caused by the drill string during forced pulling up or down, and extends the service life of the conical rubber core block. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the main structure of the present invention;

[0014] Figure 2 This is a schematic diagram of the main structure of the existing technology;

[0015] Figure 3 A schematic diagram of the conical core structure of the present invention.

[0016] The components include: 1. Ring-shaped blowout preventer body; 2. Support cylinder; 3. Piston; 4. Starting oil line; 5. Conical rubber core; 5.1. Top surface of conical rubber core block; 5.2. Gap of conical rubber core block; 5.3. Shoulder surface of conical rubber core block; 6. Closing oil line; 7. Cover; 8. Lubricating fluid injection check valve; 9. Pressure sensor; 10. Central control unit; 11. Conversion module; 12. Hydraulic control unit; 13. High-frequency hydraulic directional valve control unit; and 14. Drill string. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example:

[0019] like Figure 1-3 As shown, this embodiment of the invention provides an adaptive high-pressure sealing well annular blowout preventer. The annular blowout preventer includes a central control unit 10, a hydraulic control unit 12, and an annular blowout preventer. The annular blowout preventer includes: an annular blowout preventer body 1, a support cylinder 2, a piston 3, a starting oil line 4, a conical rubber core 5, and a closing oil line 6. The starting oil line 4 and the closing oil line 6 are connected in parallel to the hydraulic oil circuits of the hydraulic control unit 12 and the high-frequency hydraulic directional valve control unit 13, respectively. A cover 7... A pressure sensor 9 is installed between the cover 7 and the top surface 5.1 of the conical rubber core block. The pressure sensor 9 is electrically connected to the central control unit 10 via a control line. The pressure value can be displayed on the display page of the central control unit. A high-frequency hydraulic directional valve control unit 13 circuit is connected in parallel to the control circuit of the hydraulic control unit 12. The central control unit 10 is electrically connected to the conversion module 11. The conversion module 11 is electrically connected to both the hydraulic control unit 12 and the high-frequency hydraulic directional valve control unit 13. The conical rubber core 5 is composed of conical rubber core blocks arranged in a circle. There is a gap 5.2 between the conical rubber core blocks. A lubricating fluid injection check valve 8 is installed in the cavity between the cover 7 and the shoulder surface 5.3 of the conical rubber core block. The lubricating fluid flows into the drill string 14 through the gap 5.2 of the rubber core block and lubricates it. An elastic reinforcing rib is installed inside the conical rubber core 5. The conical rubber core block and the reinforcing rib are integrally formed.

[0020] An operating method for an adaptive high-pressure sealing ring blowout preventer for oil wells: Step one is the conventional operation of existing technology. When a blowout occurs, the operator sends a signal to the conversion module 11 via the central control unit 10 to select the hydraulic control unit 12 circuit for operation. The hydraulic control unit 12 controls the hydraulic fluid to flow in from the starting oil line 4 and flow out from the closing oil line 6. The piston 3 moves upward, and the top surface 5.1 of the conical rubber core block contacts the pressure sensor 9 inside the cover 7. By observing the pressure signal of the pressure sensor 9, the sealing working pressure is reached. At this time, the piston 3 rises to open the seal. The conical rubber core 5 and the drill string 14 are in a sealed working state; Step 2, when it is necessary to trip the drill string, the operator injects lubricating fluid into the cavity between the cover 7 and the shoulder surface 5.3 of the conical rubber core block through the lubricating fluid injection check valve 8. The lubricating fluid flows into the drill string 14 through the gap 5.2 of the rubber core block. The operator sends a signal to the conversion module 11 through the central control unit 10 to select the high-frequency hydraulic directional valve control unit 13 to work, and closes the hydraulic control unit 12 circuit. At this time, the hydraulic oil flows in and out alternately between the hydraulic fluid starting oil line 4 and the closing oil line 6. At this time, the piston 3 oscillates at high frequency in the sealed state; the operator observes the pressure signal change of the pressure sensor 9 and controls the frequency of the high-frequency hydraulic directional valve control unit 13 accordingly to ensure the vibration amplitude and frequency of the piston 3. Step 3: When the tripping of the drill string is completed or the blowout is controlled, and it is necessary to release the seal between the conical rubber core 5 and the drill string 14, the operator sends a signal to the conversion module 11 through the central control unit 10 to select the hydraulic control unit 12 circuit to operate, closes the valve control unit 13 circuit, and restores the conventional operation of the existing technology. At this time, the hydraulic control unit 12 controls the hydraulic fluid to flow out from the starting oil line 4 and flow in from the closing oil line 6. The piston 3 moves downward, and the top surface 5.1 of the conical rubber core block separates from the pressure sensor 9 inside the cover 7. The conical rubber core 5 returns to its original state and forms an unsealed working state with the drill string 14.

[0021] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An adaptive high-pressure sealed well annular blowout preventer, comprising a central control unit (10), a hydraulic control unit (12), and an annular blowout preventer, the annular blowout preventer comprising: The annular blowout preventer body (1), support cylinder (2), piston (3), start oil line (4), conical rubber core (5), and shut-off oil line (6); cover (7), characterized in that: a pressure sensor (9) is provided between the cover (7) and the top surface (5.1) of the conical rubber core block, and a high-frequency hydraulic directional valve control unit (13) circuit is connected in parallel on the control circuit of the hydraulic control unit (12), the central control unit (10) is electrically connected to the conversion module (11), and the conversion module (11) is electrically connected to the hydraulic control unit (12) and the high-frequency hydraulic directional valve control unit (13) respectively.

2. The adaptive high-pressure sealing annular blowout preventer for oil wells according to claim 1, characterized in that: The conical core (5) is composed of conical core blocks arranged in a circle, with conical core block gaps (5.2) between the conical core blocks.

3. The adaptive high-pressure sealing annular blowout preventer for oil wells according to claim 1, characterized in that: A lubricating fluid injection check valve (8) is provided in the cavity between the cover (7) and the shoulder surface (5.3) of the conical rubber core block.

4. The adaptive high-pressure sealing annular blowout preventer for oil wells according to claim 2, characterized in that: The conical rubber core (5) is provided with elastic reinforcing ribs inside, and the conical rubber core block and the reinforcing ribs are integrally formed.

5. The adaptive high-pressure sealing annular blowout preventer for oil wells according to claim 1, characterized in that: The tablet pressure sensor (9) is electrically connected to the central control unit (10) via a control line.

6. The operating method of the adaptive high-pressure sealing annular blowout preventer for oil wells according to claim 1, characterized in that: Step one, which is the conventional operation of existing technology, when a blowout occurs, the operator sends a signal to the conversion module (11) through the central control unit (10) to select the hydraulic control unit (12) circuit to work. By observing the pressure signal of the pressure sensor (9) reaching the sealing working pressure, the piston (3) rises to open the sealing working state between the conical rubber core (5) and the drill string (14); Step two, when it is necessary to lift or lower the drill string, the operator injects lubricating fluid into the cavity between the cover (7) and the shoulder surface (5.3) of the conical rubber core block through the lubricating fluid injection check valve (8). The central control unit (10) sends a signal to the conversion module (11) to select the high-frequency hydraulic directional valve control unit (13) to work, and closes the hydraulic control unit (12) circuit. At this time, the piston (3) oscillates at high frequency in a sealed state. Step 3: When the tripping of the drill string is completed or after the blowout control is completed, and it is necessary to release the sealing state between the conical rubber core (5) and the drill string (14), the operator sends a signal to the conversion module (11) through the central control unit (10) to select the hydraulic control unit (12) circuit to work, closes the valve control unit (13) circuit, and restores the conventional operation of the prior art.

7. The operating method of the adaptive high-pressure sealing well annular blowout preventer according to claim 1, characterized in that: Step 1, which is the conventional operation of existing technology, when a blowout occurs, the operator sends a signal to the conversion module (11) through the central control unit (10) to select the hydraulic control unit (12) circuit for operation. The hydraulic control unit (12) controls the hydraulic fluid to flow in from the starting oil line (4) and flow out from the closing oil line (6). The piston (3) moves upward, and the top surface (5.1) of the conical rubber core block contacts the pressure sensor (9) inside the cover (7). By observing the pressure signal of the pressure sensor (9), the sealing working pressure is reached. At this time, the piston (3) is rising to open the sealing working state of the conical rubber core (5) and the drill string (14). Step 2, when it is necessary to lift or lower the drill string, the operator injects lubricant into the one-way valve (8) to... Lubricating fluid is injected into the cavity between the cover (7) and the shoulder surface (5.3) of the conical rubber block. The lubricating fluid flows into the drill string (14) through the gap (5.2) of the rubber block. The operator sends a signal to the conversion module (11) through the central control unit (10) to select the high-frequency hydraulic directional valve control unit (13) to work and closes the hydraulic control unit (12) circuit. At this time, the hydraulic oil flows in and out alternately between the hydraulic fluid in the starting oil line (4) and the closing oil line (6). At this time, the piston (3) oscillates at high frequency in the sealed state. The operator controls the frequency of the high-frequency hydraulic directional valve control unit (13) accordingly by observing the pressure signal change of the pressure sensor (9) to ensure the vibration amplitude and frequency of the piston (3). Step 3: When the tripping of the drill string is completed or the blowout is controlled, and it is necessary to release the seal between the conical rubber core (5) and the drill string (14), the operator sends a signal to the conversion module (1)1 through the central control unit (10) to select the hydraulic control unit (12) circuit to work, closes the valve control unit (13) circuit, and restores the conventional operation of the prior art. At this time, the hydraulic control unit (12) controls the hydraulic fluid to flow out from the starting oil line (4) and flow in from the closing oil line (6). The piston (3) moves down, the top surface (5.1) of the conical rubber core block separates from the pressure sensor (9) inside the cover (7), and the conical rubber core (5) returns to its original state and forms an unsealed working state with the drill string (14).

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