Throttling manifold for controlling oil jacket venting and its control method

Abstract

This invention relates to a throttling manifold and its control method for controlling oil well blowout. The manifold includes an internal control line, a five-way connector, a first four-way connector, a second four-way connector, a third four-way connector, a fourth four-way connector, a fifth four-way connector, and a sixth four-way connector. The throttling manifold is a novel system composed of a conventional throttling manifold, two manual throttling valves, six flat valves, two four-way connectors, and a flanged short section. This throttling manifold has a dual-channel structure, with each channel controlled by a manual throttling valve and a manual flat valve, and a direct discharge in the middle. This invention significantly improves the safety factor of on-site operations, meets energy-saving, emission-reduction, and environmental protection requirements, effectively solves construction problems during gas well depressurization, well control, and water absorption index measurement, and has strong practicality and operability, extending the service life of the manifold and improving its throttling effect.

Description

Technical Field

[0001] This invention relates to the field of oil and gas well operations, and more specifically, to a choke manifold for controlling oil casing blowout and a control method thereof. Background Technology

[0002] During well workover operations, oil and gas wells require the installation of various supporting well control devices to ensure well control safety at the construction site. Choke manifolds are particularly important in practical applications, enabling choke circulation, pressure relief, flow diversion and venting, and control of wellhead back pressure. Currently, conventional choke manifolds are used for well workover operations in the Northwest work area, which have the following problems: ① In abnormal situations, simultaneous choke pressure relief in the tubing and casing annulus is impossible, resulting in slow choke venting speed; ② The size and direction of the tubing vent outlet cannot be controlled, preventing toxic and harmful gases from entering the separator; ③ The tubing outlet cannot be fixed; ④ The fluid channel is singular, and there is no backup channel if the valve is punctured, leading to low reliability. Therefore, there is an urgent need to solve problems such as the inability to fix the outlet during tubing venting, the inability to adjust the discharge rate, and the inability to separate and treat toxic and harmful gases such as hydrogen sulfide. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a choke manifold and its control method for controlling oil casing blowout, which solves a series of problems such as the need for choke blowout in oil and gas well depressurization, well control, and water absorption index measurement operations, and helps to reduce well control risks, reduce equipment and pipeline installation, and improve production efficiency.

[0004] The technical solution adopted by this invention to solve its technical problem is as follows: A throttling manifold for controlling oil jacket blowout is constructed, comprising an internal control line, a five-way valve, a first four-way valve, a second four-way valve, a third four-way valve, a fourth four-way valve, a fifth four-way valve, and a sixth four-way valve. The internal control line is connected to the five-way valve via a first manual flat gate valve. The five-way valve is also connected to the third, fourth, and sixth manual flat gate valves. The third manual flat gate valve is connected to the first manual throttling gate valve via a second manual flat gate valve. The first manual throttling gate valve is connected to the second four-way valve via a seventh manual flat gate valve. The fourth manual flat gate valve is connected to the second manual throttling gate valve via a fifth manual flat gate valve. The second manual throttling gate valve is connected to the sixth four-way valve via a thirteenth manual flat gate valve. The sixth manual flat gate valve is connected to the first four-way valve.

[0005] The first pipeline four-way connection is also connected to the eighth manual flat gate valve, the ninth manual flat gate valve and the eleventh manual flat gate valve. The eighth manual flat gate valve is connected to the third manual throttle gate valve. The third manual throttle gate valve is connected to the third pipeline four-way through the tenth manual flat gate valve. The ninth manual flat gate valve is connected to the fourth manual throttle valve. The fourth manual throttle gate valve is connected to the fifth pipeline four-way through the twelfth manual flat gate valve. The eleventh manual flat gate valve is connected to the fourth pipeline four-way.

[0006] The fourth pipeline four-way valve is also connected to the fifteenth manual flat gate valve, the sixteenth manual flat gate valve and the seventeenth manual flat gate valve. The fifteenth manual flat gate valve is connected to the third pipeline four-way valve. The sixteenth manual flat gate valve is used to connect to the oil pipe outlet. The seventeenth manual flat gate valve is connected to the fifth pipeline four-way valve.

[0007] The fifth pipeline tee is connected to the sixth pipeline tee, and the sixth pipeline tee is also connected to the eighteenth manual flat gate valve; the third pipeline tee is connected to the second pipeline tee, and the second pipeline tee is also connected to the fourteenth manual flat gate valve, which is used to connect to the circulation tank.

[0008] According to the above scheme, each manual throttling gate valve, each manual throttling gate valve, each pipeline four-way valve, each pipeline five-way valve, and each flange short section are equipped with connecting flanges on both sides.

[0009] According to the above scheme, the contact surface of the connecting flange is provided with a sealing steel ring groove, and the two flanges are sealed by the steel ring.

[0010] According to the above scheme, eight through holes are evenly distributed on the connecting flange, and the two connecting flanges are connected and fastened by connecting bolts.

[0011] The present invention also provides a control method for a throttling manifold for controlling oil jacket blowout, comprising the following steps:

[0012] 1) When both the tubing and casing require emergency pressure relief and blowout release, and the casing outlet needs to enter the separator, the casing outlet enters the separator for combustion and exhaust treatment via the internal control line → first manual flat gate valve → pipeline five-way valve → fourth manual flat gate valve → fifth manual flat gate valve → second manual throttle valve → thirteenth manual flat gate valve → eighteenth manual flat gate valve; the tubing outlet enters the circulation tank via the sixteenth manual flat gate valve → fourth pipeline four-way valve → eleventh manual flat gate valve → first pipeline four-way valve → eighth manual flat gate valve → third manual throttle valve → tenth manual flat gate valve → third pipeline four-way valve → second pipeline four-way valve → fourteenth manual flat gate valve.

[0013] 2) When both the tubing and casing require emergency pressure relief and blowout release, and the tubing outlet needs to enter the separator, the casing outlet is connected to the internal control line → first manual flat gate valve → pipeline five-way valve → third manual flat gate valve → second manual flat gate valve → first manual throttle gate valve → seventh manual flat gate valve → second pipeline four-way valve → fourteenth manual flat gate valve, and enters the circulation tank; the tubing outlet is connected to the sixteenth manual flat gate valve → fourth pipeline four-way valve → eleventh manual flat gate valve → first pipeline four-way valve → ninth manual flat gate valve → fourth manual throttle gate valve → twelfth manual flat gate valve → fifth pipeline four-way valve → sixth pipeline four-way valve → eighteenth manual flat gate valve, and enters the separator for exhaust treatment.

[0014] 3) Adjust the first, second, third, and fourth manual choke valves respectively to regulate the discharge rate at the casing outlet or tubing outlet, ensuring that the bottom hole pressure is slightly greater than the formation pressure, maintaining wellbore balance, and preventing overflow, leakage, and blowout hazards.

[0015] The throttling manifold and its control method for controlling oil jacket blowout according to the present invention have the following beneficial effects:

[0016] This invention provides a novel throttling manifold composed of a manual throttling valve and a flat valve. This manifold allows for rigid fixing of the tubing outlet, resolving pipeline fluctuation issues; it also allows for adjustment of the manual throttling valve to control the tubing venting outlet flow; in emergencies, it enables simultaneous throttling and venting of the tubing and casing; and it features a dual configuration of the manual throttling valve and access channels, allowing for the use of the alternative channel if one channel fails. On-site, based on pressure, gas volume, and hydrogen sulfide levels, the outlet can be controlled to either enter a tank or a separator, achieving selective and safe venting. This invention meets energy-saving, emission-reduction, and environmental protection requirements, effectively solving construction difficulties during gas well depressurization, well control, and water absorption index measurement. It boasts a high safety factor, simple operation, and excellent throttling and venting effect, significantly improving operational safety. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0018] Figure 1 This is a schematic diagram of one of the flow directions of the throttling manifold used to control the blowout of the oil jacket;

[0019] Figure 2 This is a schematic diagram of the flow direction of the throttling manifold used to control the blowout of the oil jacket;

[0020] Figure 3 This is the front view of the throttling manifold used to control the blowout of the oil jacket;

[0021] Figure 4 This is a top view of the throttling manifold used to control the blowout of the oil jacket.

[0022] Explanation of reference numerals in the attached diagram: 1-Internal control pipeline; 2-First manual flat gate valve; 3-First manual throttle gate valve; 4-Second manual flat gate valve; 5-Third manual flat gate valve; 6-Pipeline five-way valve; 7-Fourth manual flat gate valve; 8-Fifth manual flat gate valve; 9-Second manual throttle gate valve; 10-Sixth manual flat gate valve; 11-Seventh manual flat gate valve; 12-Third manual throttle gate valve; 13-Eighth manual flat gate valve; 14-First pipeline four-way valve; 15-Ninth manual flat gate valve; 16-Fourth manual flat gate valve; Manual throttling gate valve; 17-Tenth manual flat gate valve; 18-Eleventh manual flat gate valve; 19-Twelfth manual flat gate valve; 20-Thirteenth manual flat gate valve; 21-Fourteenth manual flat gate valve; 22-Second pipeline four-way valve; 23-Third pipeline four-way valve; 24-Fifteenth manual flat gate valve; 25-Fourth pipeline four-way valve; 26-Sixteenth manual flat gate valve; 27-Seventeenth manual flat gate valve; 28-Fifth pipeline four-way valve; 29-Sixth pipeline four-way valve; 30-Eighteenth manual flat gate valve. Detailed Implementation

[0023] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0024] like Figure 1-4 As shown, the present invention provides a simple, safe and reliable method that utilizes a novel throttling manifold to fix the oil pipe outlet, control the outlet size, simultaneously release pressure from the oil casing, perform emergency release, and separate toxic and harmful substances such as hydrogen sulfide.

[0025] The throttling manifold for controlling oil casing venting consists of a conventional throttling manifold, two manual throttling valves, six flat valves, two four-way valves, and flanged short sections, forming a new type of throttling manifold. Each valve, four-way valve, and flanged short section has connecting flanges on both sides. The contact surfaces of the connecting flanges have sealing steel ring grooves, and the two flanges are sealed together by the steel rings. Eight through holes are evenly distributed on the connecting flanges, each equipped with matching connecting bolts. The two connecting flanges are connected and secured with these bolts. By using the manual throttling valves and flat valves to change the flow direction of the oil pipe and casing outlets, mutual interference between the oil pipe and casing is achieved. The venting outlet size is controlled by adjusting the opening and closing of the manual throttling valves. A dual configuration of manual throttling valves and channels is used; if one channel fails, the gate valve can be switched to control the oil pipe outlet to use the other channel. On-site, based on pressure, gas volume, and hydrogen sulfide levels, the outlet can be controlled to either enter the tank or the separator, achieving selective and safe venting.

[0026] The throttling manifold for controlling oil jacket blowout of the present invention includes an internal control line 1, a five-way valve 6, a first four-way valve 14, a second four-way valve 22, a third four-way valve 23, a fourth four-way valve 25, a fifth four-way valve 28, and a sixth four-way valve 29. The internal control line is connected to the five-way valve 6 via a first manual flat gate valve 2. The five-way valve 6 is also connected to the third manual flat gate valve 5, the fourth manual flat gate valve 7, and the sixth manual flat gate valve 10. The third manual flat gate valve 5 is connected to the first manual throttling gate valve 3 via a second manual flat gate valve 4. The first manual throttling gate valve 3 is connected to the second four-way valve 22 via a seventh manual flat gate valve 11. The fourth manual flat gate valve 7 is connected to the second manual throttling gate valve 9 via a fifth manual flat gate valve 8. The second manual throttling gate valve 9 is connected to the sixth four-way valve 29 via a thirteenth manual flat gate valve 20. The sixth manual flat gate valve 10 is connected to the first four-way valve 14.

[0027] The first pipeline four-way 14 is also connected to the eighth manual flat gate valve 13, the ninth manual flat gate valve 15 and the eleventh manual flat gate valve 18. The eighth manual flat gate valve 13 is connected to the third manual throttle gate valve 12. The third manual throttle gate valve 12 is connected to the third pipeline four-way 23 through the tenth manual flat gate valve 17. The ninth manual flat gate valve 15 is connected to the fourth manual throttle valve 16. The fourth manual throttle valve 16 is connected to the fifth pipeline four-way 28 through the twelfth manual flat gate valve 19. The eleventh manual flat gate valve 18 is connected to the fourth pipeline four-way 25.

[0028] The fourth pipeline four-way 25 is also connected to the fifteenth manual flat gate valve 24, the sixteenth manual flat gate valve 26 and the seventeenth manual flat gate valve 27. The fifteenth manual flat gate valve 24 is connected to the third pipeline four-way 23. The sixteenth manual flat gate valve 26 is used to connect to the oil pipe outlet. The seventeenth manual flat gate valve 27 is connected to the fifth pipeline four-way 28.

[0029] The fifth pipeline tee 28 is connected to the sixth pipeline tee 29, and the sixth pipeline tee 29 is also connected to the eighteenth manual flat gate valve 30; the third pipeline tee 23 is connected to the second pipeline tee 22, and the second pipeline tee 22 is also connected to the fourteenth manual flat gate valve 21, which is used to connect to the circulation tank.

[0030] Each manual throttle gate valve, each pipeline four-way valve, each pipeline five-way valve, and each flange short section is equipped with connecting flanges on both sides. The contact surface of the connecting flanges has a sealing steel ring groove, and the two flanges are sealed together by the steel ring. Eight through holes are evenly distributed on the connecting flanges, and the two connecting flanges are connected and fastened together using connecting bolts.

[0031] The present invention also provides a control method for a throttling manifold for controlling oil jacket blowout, comprising the following steps:

[0032] 1) When both the tubing and casing require emergency pressure relief and blowout release, and the casing outlet needs to enter the separator, the casing outlet enters the separator for combustion and exhaust treatment via internal control line 1 → first manual flat gate valve 2 → pipeline five-way valve 6 → fourth manual flat gate valve 7 → fifth manual flat gate valve 8 → second manual throttle valve 9 → thirteenth manual flat gate valve 20 → eighteenth manual flat gate valve 30; the tubing outlet enters the circulation tank via sixteenth manual flat gate valve 26 → fourth pipeline four-way valve 25 → eleventh manual flat gate valve 18 → first pipeline four-way valve 14 → eighth manual flat gate valve 13 → third manual throttle valve 12 → tenth manual flat gate valve 17 → third pipeline four-way valve 23 → second pipeline four-way valve 22 → fourteenth manual flat gate valve 21.

[0033] 2) When both the tubing and casing require emergency pressure relief and blowout release, and the tubing outlet needs to enter the separator, the casing outlet is connected to the internal control line 1 → first manual flat gate valve 2 → pipeline five-way valve 6 → third manual flat gate valve 5 → second manual flat gate valve 4 → first manual throttle valve 3 → seventh manual flat gate valve 11 → second pipeline four-way valve 22 → fourteenth manual flat gate valve 21, and enters the circulation tank; the tubing outlet is connected to the sixteenth manual flat gate valve 26 → fourth pipeline four-way valve 25 → eleventh manual flat gate valve 18 → first pipeline four-way valve 14 → ninth manual flat gate valve 15 → fourth manual throttle valve 16 → twelfth manual flat gate valve 19 → fifth pipeline four-way valve 28 → sixth pipeline four-way valve 29 → eighteenth manual flat gate valve 30, and enters the separator for combustion and exhaust treatment;

[0034] 3) Adjust the first manual choke valve 3, the second manual choke valve 9, the third manual choke valve 12, and the fourth manual choke valve 16 respectively to adjust the discharge rate of the casing outlet or tubing outlet, so as to ensure that the bottom hole pressure is slightly greater than the formation pressure, maintain the wellbore balance, and prevent the occurrence of dangerous situations such as leakage, overflow, and blowout.

[0035] The present invention has the following advantages:

[0036] 1) By adjusting the manual throttle valve, flat valve, and flange short section switch, the independent venting of the oil pipe and casing is achieved, realizing simultaneous venting of the oil pipe and casing without interference between them.

[0037] 2) On-site, the outlet can be controlled to enter the tank or the separator according to the pressure and gas volume, so as to achieve selective venting.

[0038] 3) The flow rate at the vent outlet is controlled by adjusting the switch of the manual throttle valve. The throttle venting effect is good and can effectively prevent the occurrence of phenomena such as severe wellbore depletion, formation collapse, and formation activation caused by uncontrolled venting. It can achieve the effect of safe venting and pressure relief.

[0039] 4) If the casing annulus is blocked, preventing normal pressure relief and venting, and the well pressure is high, the gas volume is large, and it contains toxic and harmful gases such as hydrogen sulfide, the tubing pressure can be controlled through a new type of throttling manifold, and the outlet can be introduced into a separator to introduce toxic and harmful gases such as hydrogen sulfide into the separator for desulfurization treatment, effectively solving the problem of the casing being difficult to safely vent.

[0040] 5) The new throttling manifold uses a manual throttling valve and dual channel configuration. If one channel fails, the gate valve can be adjusted to control the oil pipe outlet to use the other channel, ensuring the operability and safety of oil pipe venting and improving the reliability of the new throttling manifold.

[0041] 6) It can effectively solve the problems of well-killing fluid overflow and spraying during tubing blowout, effectively reduce environmental risks, realize the recycling of well-killing fluid, and reduce construction costs.

[0042] 7) When the oil pipe is vented, a rigid pipeline is used at the outlet and fixed with a base or other rigid means to achieve rapid connection of the pipeline and improve the safety factor of the work site.

[0043] 8) The new type of throttling manifold has a simple structure and features easy operation, labor saving and high efficiency.

[0044] 9) The new type of throttling manifold is suitable for downhole operations such as gas well depressurization, well control, and water absorption index measurement, and can effectively solve the construction difficulties when gas well depressurization, well control, and water absorption index measurement.

[0045] This invention, applied to oil and gas wells, utilizes a novel throttling manifold to solve the problems of mutual interference at the outlets during simultaneous pressure relief, blowout control, well control, and water suction testing operations in oil and gas wells. These problems include the inability to control the tubing outlet flow, the inability to fix the tubing outlet, and the introduction of toxic and harmful gases such as hydrogen sulfide into the separator. The novel throttling manifold of this invention offers a high safety factor, simple operation, and excellent throttling and blowout control effects.

[0046] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A throttling manifold for controlling oil jacket venting, characterized in that, The system includes an internal control pipeline (1), a five-way valve (6), a first four-way valve (14), a second four-way valve (22), a third four-way valve (23), a fourth four-way valve (25), a fifth four-way valve (28), and a sixth four-way valve (29). The internal control pipeline is connected to the five-way valve (6) via a first manual flat gate valve (2). The five-way valve (6) is also connected to a third manual flat gate valve (5), a fourth manual flat gate valve (7), and a sixth manual flat gate valve (10). The third manual flat gate valve (5) is open to... The second manual flat gate valve (4) is connected to the first manual throttle gate valve (3). The first manual throttle gate valve (3) is connected to the second pipeline four-way (22) through the seventh manual flat gate valve (11). The fourth manual flat gate valve (7) is connected to the second manual throttle gate valve (9) through the fifth manual flat gate valve (8). The second manual throttle gate valve (9) is connected to the sixth pipeline four-way (29) through the thirteenth manual flat gate valve (20). The sixth manual flat gate valve (10) is connected to the first pipeline four-way (14). The first pipeline four-way (14) is also connected to the eighth manual flat gate valve (13), the ninth manual flat gate valve (15) and the eleventh manual flat gate valve (18). The eighth manual flat gate valve (13) is connected to the third manual throttle gate valve (12). The third manual throttle gate valve (12) is connected to the third pipeline four-way (23) through the tenth manual flat gate valve (17). The ninth manual flat gate valve (15) is connected to the fourth manual throttle gate valve (16). The fourth manual throttle gate valve (16) is connected to the fifth pipeline four-way (28) through the twelfth manual flat gate valve (19). The eleventh manual flat gate valve (18) is connected to the fourth pipeline four-way (25). The fourth pipeline tee (25) is also connected to the fifteenth manual flat gate valve (24), the sixteenth manual flat gate valve (26) and the seventeenth manual flat gate valve (27). The fifteenth manual flat gate valve (24) is connected to the third pipeline tee (23). The sixteenth manual flat gate valve (26) is used to connect to the oil pipe outlet. The seventeenth manual flat gate valve (27) is connected to the fifth pipeline tee (28). The fifth pipeline tee (28) is connected to the sixth pipeline tee (29), and the sixth pipeline tee (29) is also connected to the eighteenth manual flat gate valve (30); the third pipeline tee (23) is connected to the second pipeline tee (22), and the second pipeline tee (22) is also connected to the fourteenth manual flat gate valve (21), which is used to connect to the circulation tank.

2. The throttling manifold for controlling oil jacket blowout according to claim 1, characterized in that, Each manual throttle gate valve, each manual throttle gate valve, each pipeline four-way valve, each pipeline five-way valve, and each flange short section is equipped with a connecting flange on both sides.

3. The throttling manifold for controlling oil jacket blowout according to claim 2, characterized in that, The connecting flange contact surface is provided with a sealing steel ring groove, and the two flanges are sealed by the steel ring.

4. The throttling manifold for controlling oil jacket blowout according to claim 2, characterized in that, The connecting flange has eight through holes evenly distributed on it, and the two connecting flanges are connected and fastened by connecting bolts.

5. A control method for a throttling manifold for controlling oil jacket blowout as described in claim 1, characterized in that, Includes the following steps: 1) When the tubing and casing need to be depressurized and vented simultaneously, and the casing outlet needs to enter the separator, the casing outlet enters the separator for combustion and exhaust treatment via the internal control line (1) → first manual flat gate valve (2) → pipeline five-way (6) → fourth manual flat gate valve (7) → fifth manual flat gate valve (8) → second manual throttle gate valve (9) → thirteenth manual flat gate valve (20) → eighteenth manual flat gate valve (30); the tubing outlet enters the circulating tank via the sixteenth manual flat gate valve (26) → fourth pipeline four-way (25) → eleventh manual flat gate valve (18) → first pipeline four-way (14) → eighth manual flat gate valve (13) → third manual throttle gate valve (12) → tenth manual flat gate valve (17) → third pipeline four-way (23) → second pipeline four-way (22) → fourteenth manual flat gate valve (21); 2) When the oil pipe and casing need to be depressurized and released simultaneously, and the oil pipe outlet needs to enter the separator, the casing outlet enters the circulation tank via the internal control line (1) → first manual flat gate valve (2) → pipeline five-way (6) → third manual flat gate valve (5) → second manual flat gate valve (4) → first manual throttle gate valve (3) → seventh manual flat gate valve (11) → second pipeline four-way (22) → fourteenth manual flat gate valve (21); the oil pipe outlet enters the separator for combustion treatment via the sixteenth manual flat gate valve (26) → fourth pipeline four-way (25) → eleventh manual flat gate valve (18) → first pipeline four-way (14) → ninth manual flat gate valve (15) → fourth manual throttle gate valve (16) → twelfth manual flat gate valve (19) → fifth pipeline four-way (28) → sixth pipeline four-way (29) → eighteenth manual flat gate valve (30). 3) Adjust the first manual choke valve (3), the second manual choke valve (9), the third manual choke valve (12), and the fourth manual choke valve (16) respectively to adjust the discharge rate of the casing outlet or tubing outlet, ensure that the bottom hole pressure is slightly greater than the formation pressure, maintain the wellbore balance, and prevent overflow, leakage, and blowout.

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