Well shut-in protection device for wellhead sealing failure of pumping well of mining stopping machine

Abstract

The utility model discloses a shut-in protection device for well mouth sealing failure of a shut-off machine pumping well. The shut-in protection device comprises a lower bottom plate, an upper bottom plate, a sealing rubber ring, a pressure-bearing bolt, a nut, a slip outer cylinder, a slip, a propelling cylinder, an assembly of the propelling cylinder and a semi-sealing flashboard. According to the device, the lower polish rod is hung through the slip outer cylinder and the slip, and preparation is made for cutting off the upper polish rod to install the device; the device is installed and fixed on the upper portion of the double-ram blowout preventer through the lower bottom plate, the upper bottom plate, the sealing rubber ring, the pressure-bearing bolt and the nut, and oil gas leaked from a wellhead is controlled in the device. By starting an external hydraulic pump, hydraulic oil drives the piston in the propelling cylinder to move towards a well mouth, and the semi-sealing flashboard sealing core is driven to tightly hold the outer shell of the polish rod sealer, so that well sealing is achieved. Compared with the mode that the wellhead is controlled through a well killing means, the device can safely and effectively control the wellhead, and the situation that the oil well reservoir is damaged by well killing operation, and then the oil well recovery ratio is affected is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of oil well wellhead overflow control, in particular to a wellhead sealing failure protection device for a pumping well with a stopped production machine. Background Art

[0002] After the oil wells were machine-drained for a period of time, the formation and reservoir pressure dropped significantly, resulting in extremely low liquid production, which was insufficient to support the mining cost. The operation site adopted the method of shutting down the well and stopping production. Due to the long shut-in time, the rubber sealing components inside the double-gate blowout preventer and the polished rod seal at the wellhead corroded and aged, resulting in the failure of the wellhead seal. After the formation and reservoir pressure recovered, it increased, pushing the oil and gas in the wellbore to gush out to the wellhead, and the oil and gas broke through the wellhead seal to form an overflow.

[0003] At present, well killing is used on site to control wellhead overflow. Once the well is killed, the reservoir will be damaged, which will have irreversible consequences on the subsequent recovery rate of the oil well.

[0004] Therefore, this problem urgently needs to be improved and enhanced. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the purpose of the utility model is to provide a wellhead sealing protection device for wells pumping out of production machinery, aiming to solve the wellhead control problem after the double gate blowout preventer and the bare rod sealer of the well pumping out of production machinery all fail.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] In the first aspect, a sealing and protection device for a wellhead seal failure of a pumping wellhead of a stopped production machine is provided, which comprises a polished rod, a polished rod sealer is arranged on the outer sleeve of the polished rod, and a double-gate blowout preventer is connected to the lower end of the polished rod sealer, and further comprises:

[0008] A sealing cylinder is sleeved outside the polished rod sealer, and two cylinders are symmetrically provided on the sealing cylinder;

[0009] At least two hydraulic assemblies are arranged in the cylinder barrel, and a semi-closed gate is connected in the hydraulic assembly, and the semi-closed gate is adapted to the outer diameter of the polished rod sealer;

[0010] A fixing assembly is provided on the double-gate blowout preventer and is connected to the sealing cylinder to fix the sealing cylinder to the upper end of the double-gate blowout preventer;

[0011] The polished rod fixing piece is arranged on the polished rod and is located at the upper end of the polished rod sealer.

[0012] Furthermore, the hydraulic assembly comprises:

[0013] The connecting sleeve A is provided with double-ended threads and is screwed and fixed in the cylinder;

[0014] A straightening sleeve, arranged on a side of the connecting sleeve A away from the cylinder barrel;

[0015] A propulsion cylinder is threadedly fixed on the centralizing sleeve, and the propulsion cylinder is provided with an oil port A and an oil port B;

[0016] A propulsion piston has one end abutting against the inside of the propulsion cylinder, and the other end passes through the straightening sleeve and abuts against the connecting sleeve, and the other end of the propulsion piston is connected to the semi-closed gate plate.

[0017] Furthermore, the fixing assembly comprises:

[0018] The upper bottom plate is in contact with the upper end of the double-gate blowout preventer and is connected to the sealing cylinder as a whole. The lower end surface is provided with a circular notch for placing a sealing rubber ring;

[0019] A lower bottom plate abutting against the lower end of the double-gate blowout preventer;

[0020] A plurality of pressure-bearing screw rods penetrate through the four corners of the upper base plate and the lower base plate and are fixed by nuts.

[0021] Furthermore, the lower base plate includes a first clamping plate and a second clamping plate, and the first clamping plate and the second clamping plate are clamped together via a Z-shaped protrusion.

[0022] Furthermore, the polished rod fixing member comprises:

[0023] The slip outer cylinder is sleeved outside the polished rod and abuts against the upper end of the polished rod sealer;

[0024] The slip is inserted between the slip outer tube and the polished rod to fix the polished rod.

[0025] Furthermore, the sealing cylinder includes a main cylinder and a secondary cylinder, the diameter of the secondary cylinder is smaller than that of the main cylinder, and the main cylinder and the secondary cylinder are fixedly connected by a connecting sleeve B, the inner diameter of the connecting sleeve B is adapted to the light rod, and the main cylinder is sleeved outside the light rod sealer.

[0026] Furthermore, a stopcock is provided in the auxiliary tube, and two lifting ears are symmetrically provided on the auxiliary tube.

[0027] Furthermore, a cock is provided at one end of the auxiliary cylinder away from the main cylinder. The cock is connected to the auxiliary cylinder via a connecting sleeve C, and a pressure relief port is provided on the cock.

[0028] Furthermore, a pressure gauge is provided on the main cylinder to detect the pressure value in the main cylinder.

[0029] The utility model discloses a wellhead sealing protection device for failure of sealing of a wellhead of a pumping well stopped by a production stop machine, comprising: a lower base plate, an upper base plate, a sealing rubber ring, a pressure-bearing bolt, a nut, a slip outer cylinder, a slip, a propulsion cylinder and its components, and a semi-sealed gate plate; in the present application, the lower light rod is suspended by means of the slip outer cylinder and the slip, so as to prepare for cutting off the upper light rod and installing the present device; the present device is installed and fixed on the upper part of the double gate blowout preventer by means of the lower base plate, the upper base plate, the sealing rubber ring, the pressure-bearing bolt and the nut, so as to control the oil and gas leaking from the wellhead inside the device; by starting an external hydraulic pump, the hydraulic oil drives the piston in the propulsion cylinder to move toward the wellhead, driving the semi-sealed gate plate sealing core to hold the outer shell of the light rod sealer tightly, thereby sealing the well. Compared with the method of controlling the wellhead by well killing means, the present device can safely and effectively control the wellhead, and prevent the well killing operation from damaging the oil well reservoir and thus affecting the oil well recovery rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of the structure of a wellhead sealing protection device for a pumping well with a stopped production machine provided by the utility model;

[0031] Figure 2 A schematic diagram of a partial cross-sectional structure of a wellhead sealing protection device for a pumping well with a stopped production machine provided by the utility model;

[0032] Figure 3 A schematic diagram of the secondary cylinder structure of a wellhead sealing protection device for a pumping well with a stopped production machine provided by the utility model;

[0033] Figure 4 The utility model provides a structural schematic diagram of the fixing components of a well sealing protection device for failure of the seal of a wellhead when a pumping machine is shut down.

[0034] 1. Bare rod; 2. Pressure-bearing screw; 3. Nut; 4. Lower base plate; 5. Double-gate blowout preventer; 6. Sealing rubber ring; 7. Upper base plate; 8. Oil port A; 9. Propelling cylinder; 10. Propelling piston; 11. Oil port B; 12. Straightening sleeve; 13. Connecting sleeve A; 14. Cylinder barrel; 15. Semi-closed gate; 16. Main barrel; 17. Bare rod sealer; 18. Slip outer barrel; 19. Slip; 20. Pressure gauge; 21. Connecting sleeve B; 22. Auxiliary cylinder; 23. Plug valve; 24. Lifting ear; 25. Connecting sleeve C; 26 Cock; 27. Pressure relief port. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and effect of the utility model clearer and more specific, the utility model is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0036] It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it can be directly on the other component or indirectly on the other component. When a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component.

[0037] It should also be noted that the same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0038] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0039] In the implementation of the present utility model, please refer to Figure 1-Figure 4 , a wellhead sealing protection device for wells with wellhead seal failure when the well is stopped from pumping oil. The light rod 1, the light rod sealer 17, and the double gate blowout preventer 5 are devices installed at the wellhead. The light rod 1 is an independent entity connected to the oil pumping device in the wellbore of the oil well. It is composed of multiple sections of rods, and they are threadedly connected in pairs. The uppermost part is connected to the oil production machine during the well pumping. The outer sleeve of the light rod 1 is provided with a light rod sealer 17, and the lower end of the light rod sealer 17 is screwed to the double gate blowout preventer 5. The light rod sealer 17 is a combined sealing device with a through hole in the middle, and the intermediate hole is for the light rod 1 to pass through. The stuffing box has a tubular stuffing, and the plugging device is equipped with a sealing capsule to seal the light rod 1 to prevent oil and gas leakage.

[0040] It should be noted that, in this embodiment, please refer to Figure 1 and Figure 2 The semi-closed gate plate 15 is an L-shaped plate with a semicircular inner side and abuts against the inner wall of the sealing cylinder. When in use, the hydraulic assembly is started to push the semi-closed gate plate 15 inward, and the semi-closed gate plates 15 on both sides move inward to lock the polished rod sealer 17, so that the inside of the polished rod sealer 17 further locks the polished rod 1 and forms a sealed partition to block oil and gas leakage.

[0041] In addition, even if oil and gas leak from the inside of the polished rod sealer 17, the sealing tube will carry the leaked oil and gas, and the semi-closed gate 15 will also seal the bottom of the sealing tube to further form a seal to prevent oil and gas from leaking outward and polluting the surrounding environment.

[0042] Specifically, see Figure 1 and Figure 2 Before installing this device, the wellhead needs to be processed. Place the slip outer tube 18 and slip 19 on the upper part of the polished rod sealer 17 to hang all the polished rods in the wellbore, and then use a shearing tool to cut the polished rods within 500mm from the upper end of the slip outer tube 18 to facilitate the installation of this device.

[0043] In this example, see Figure 1 and Figure 2 The hydraulic assembly includes a connecting sleeve A13, a straightening sleeve 12, a thrust cylinder 9 and a thrust piston 10; the connecting sleeve A13 is provided with a double-end thread and is screwed and fixed in the cylinder 14; the thrust cylinder 9 is screwed and fixed on the outside of the connecting sleeve A13, and the thrust cylinder 9 is provided with an oil port A8 and an oil port B11; the straightening sleeve 12 is provided on the side of the thrust cylinder 9 away from the cylinder 14, and is screwed and fixed thereto; one end of the thrust piston 10 abuts against the inside of the thrust cylinder 9, and the other end passes through the straightening sleeve 12 and abuts against the connecting sleeve, and the other end of the thrust piston 10 is connected to the semi-closed gate plate 15.

[0044] Please note that Figure 2 In this embodiment, the thrust piston 10 is I-shaped, with pistons at both ends, connected by a connecting rod in the middle, and the middle connecting rod is limited by a straightening sleeve 12 to prevent the thrust piston 10 from shifting; when in use, hydraulic oil is input into the thrust cylinder 9 through the oil port A8, and the hydraulic oil pushes the thrust piston 10 to move inward, thereby causing the inside of the thrust piston 10 to move inward along the cylinder 14, pushing the semi-sealed gate plate 15 to move, forming a locking seal to prevent oil and gas leakage.

[0045] In the implementation of the present utility model, please refer to Figure 1 and Figure 4 The fixing assembly includes an upper base plate 7 and a lower base plate 4: the upper base plate 7 is abutted against the upper end of the double-gate blowout preventer 5 and is connected to the sealing cylinder as a whole. In addition, a circular notch is opened on the downward side of the upper base plate 7, and a sealing rubber ring 6 is arranged in the notch to further prevent oil and gas leakage; the lower base plate 4 is abutted against the lower end of the double-gate blowout preventer 5; a plurality of pressure-bearing screws 2 pass through the four corners of the upper base plate 7 and the lower base plate 4, and are fixed by nuts 3 to stably fix the sealing cylinder on the double-gate blowout preventer 5, thereby improving the stability of the device.

[0046] Also, see Figure 4The lower bottom plate 4 is divided into two parts, a first clamping plate and a second clamping plate. The first clamping plate and the second clamping plate are clamped together by a Z-shaped protrusion, and the middle part of the lower bottom plate 4 is a circular hole to facilitate fitting to the connection at the lower end of the double-gate blowout preventer 5.

[0047] In this example, see Figure 1-Figure 3 The sealing tube includes a main tube 16 and a secondary tube 22. The diameter of the secondary tube 22 is smaller than that of the main tube 16. Two lifting ears 24 are symmetrically arranged on the secondary tube 22. The main tube 16 and the secondary tube 22 are fixedly connected by a connecting sleeve B21. The inner diameter of the connecting sleeve B21 is adapted to the light rod 1. The main tube 16 is sleeved outside the light rod sealer 17.

[0048] See also Figure 3 A plug valve 23 is provided in the secondary cylinder 22 to form a third-level sealing structure to prevent oil and gas leakage. When the oil and gas in the main cylinder 16 are full, the plug valve 23 can be rotated to form a seal for the secondary cylinder 22.

[0049] Also, see Figure 3 A cock 26 is also provided at one end of the secondary cylinder 22 away from the main cylinder 16. The cock 26 is connected to the secondary cylinder 22 through a connecting sleeve C25, and a pressure relief port 27 is also provided on the cock 26. When the stopcock 23 is damaged, the cock 26 is still used to seal the secondary cylinder 22. If the pressure in the cylinder is too high, the pressure relief port 27 can be opened to relieve the pressure.

[0050] Specifically, the present invention includes the following steps when implemented:

[0051] 1. Installation: Before installation, open the surface flow diversion to reduce the wellhead pressure and facilitate wellhead operation. First, place the slip outer tube 18 and slip 19 on the rod sealer 17, clamp the rod 1, and then use the shearing tool to cut the rod about 500mm from the upper end of the slip outer tube 18. Next, open the plug valve 23 and cock 26, fix the sling on the lifting lug 24, and use the lifting tool to accurately place the device on the double gate blowout preventer 5, then place the lower base plate 4 under the double gate blowout preventer 5, and fix it with the pressure screw 2 and nut 3. The sealing rubber ring installed at the bottom of the upper base plate 7 of this device can control the oil and gas leaking from the wellhead inside the device.

[0052] 2. Well sealing: Connect the hydraulic pump pipeline to the oil ports A8 and B11 on the left and right sides, start the hydraulic pump, turn the reversing valve, and the hydraulic oil enters the thrust cylinder 9 from the oil port A8 to drive the thrust piston 10 to move toward the wellhead along the straightening sleeve 12. The sealing core in the semi-sealed gate 15 slowly holds the outer shell of the rod sealer 17. At the same time, the hydraulic oil and air in the cylinder 14 flow back to the hydraulic pump tank from the oil port B11. When the pressure reaches about 10Mpa, turn off the hydraulic pump. At the same time, observe that there is no oil or gas flowing out of the pressure relief port 27, then close the plug valve 23 and cock 26 to complete the well sealing.

[0053] 3. Disassembly: First, open cock 26 and plug valve 23 respectively to eliminate the trapped pressure in the device, then remove the hydraulic pump oil pressure, start the hydraulic pump, turn the reversing valve, and the hydraulic oil enters the thrust cylinder 9 from the oil port B11 to drive the thrust piston 10 to move away from the wellhead along the straightening sleeve 12. The sealing core in the semi-closed gate 15 slowly loosens the rod sealer 17. At the same time, the hydraulic oil in the thrust cylinder 9 flows back to the hydraulic pump tank from the oil port A8. When the thrust piston 10 contacts the side wall of the thrust cylinder 9, the hydraulic pump starts to pressurize, and the hydraulic pump can be turned off to remove the connecting pipeline. Finally, fix the sling on the lifting lug 24, use the lifting tool to gently drive, remove the pressure nut 3 and screw 2, take out the lower base plate 4, and hang down the device.

[0054] The technical solution adopted by the utility model can safely and effectively control the wellhead during use, without performing well killing operations to damage the oil well reservoir and thus affect the oil well recovery rate, and has the following beneficial effects:

[0055] 1. Practical and cost-saving: When the double-gate blowout preventer and the polished rod sealer of the well stop pumping machine all fail, the wellhead overflows. This device can quickly realize the wellhead control, solving the problems of high well killing cost and great damage to the oil well reservoir.

[0056] 2. Safe and effective: This device utilizes existing wellhead equipment and is equipped with matching components. Through the components, it can successively realize the functions of hanging the lower polished rod, controlling the oil and gas leaking from the wellhead inside the device, and sealing the well, which can safely and effectively control the wellhead.

[0057] 3. Environmental protection: After the device is installed, crude oil will not continue to overflow to the ground and pollute the environment.

[0058] Those skilled in the art will readily come up with other embodiments of the present invention after considering the specification and practicing the solutions disclosed herein. The present invention is intended to cover any variations, uses or adaptations of the present invention, which follow the general principles of the present invention and include common knowledge or customary technical means in the art that are not disclosed in the present disclosure. The specification and examples are to be regarded as exemplary only, and the true scope and spirit of the present invention are indicated by the claims.

Claims

1. A wellhead sealing protection device for a pumping well when the wellhead seal fails, comprising a polished rod, a polished rod sealer is disposed on the outer sleeve of the polished rod, and a double-gate blowout preventer is connected to the lower end of the polished rod sealer, characterized in that: It also includes: A sealing cylinder is sleeved outside the polished rod sealer, and two cylinders are symmetrically provided on the sealing cylinder; At least two hydraulic assemblies are arranged in the cylinder barrel, and a semi-closed gate is connected in the hydraulic assembly, and the semi-closed gate is adapted to the outer diameter of the polished rod sealer; A fixing assembly is provided on the double-gate blowout preventer and is connected to the sealing cylinder to fix the sealing cylinder to the upper end of the double-gate blowout preventer; The polished rod fixing piece is arranged on the polished rod and is located at the upper end of the polished rod sealer.

2. The wellhead sealing protection device for pumping wells without production as claimed in claim 1 is characterized in that: The hydraulic assembly comprises: The connecting sleeve A is provided with double-ended threads, one end of which is screwed and fixed in the cylinder; A propulsion cylinder is threadedly fixed to the other end of the connecting sleeve A, and the propulsion cylinder is provided with an oil port A and an oil port B; A straightening sleeve is threadedly connected to the propulsion tube and is located on a side of the propulsion tube facing the cylinder barrel; A propulsion piston has one end abutting against the inside of the propulsion cylinder, and the other end passes through the straightening sleeve and abuts against the connecting sleeve, and the other end of the propulsion piston is connected to the semi-closed gate plate.

3. The wellhead sealing protection device for pumping wells without production as claimed in claim 1 is characterized in that: The fixing assembly comprises: The upper bottom plate is in contact with the upper end of the double-gate blowout preventer and is connected to the sealing cylinder as a whole. The lower end surface is provided with a circular notch for placing a sealing rubber ring; A lower bottom plate abutting against the lower end of the double-gate blowout preventer; A plurality of pressure-bearing screw rods penetrate through the four corners of the upper base plate and the lower base plate and are fixed by nuts.

4. The wellhead sealing protection device for pumping wells without production as claimed in claim 3 is characterized in that: The lower base plate includes a first clamping plate and a second clamping plate, and the first clamping plate and the second clamping plate are clamped together via a Z-shaped protrusion.

5. The wellhead sealing protection device for pumping wells without production as claimed in claim 1 is characterized in that: The polished rod fixing member comprises: The slip outer cylinder is sleeved outside the polished rod and abuts against the upper end of the polished rod sealer; The slip is sleeved and inserted between the slip outer tube and the polished rod to suspend and fix the polished rod, and the slip is conical.

6. The wellhead sealing protection device for pumping wells without production as claimed in claim 1 is characterized in that: The sealing cylinder includes a main cylinder and a secondary cylinder. The diameter of the secondary cylinder is smaller than that of the main cylinder. The main cylinder and the secondary cylinder are fixedly connected by a connecting sleeve B. The inner diameter of the connecting sleeve B is adapted to the polished rod. The main cylinder is sleeved outside the polished rod sealer.

7. The wellhead sealing protection device for pumping wells without production as claimed in claim 6 is characterized in that: A stopcock is arranged in the auxiliary tube, and two lifting ears are symmetrically arranged on the auxiliary tube.

8. The wellhead sealing protection device for pumping wells without production as claimed in claim 6 is characterized in that: A cock is also provided at one end of the secondary cylinder away from the main cylinder. The cock is connected to the secondary cylinder via a connecting sleeve C, and a pressure relief port is also provided on the cock.

9. The wellhead sealing protection device for pumping wells without production as claimed in claim 6 is characterized in that: The main cylinder is also provided with a pressure gauge to detect the pressure value in the main cylinder.

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