Christmas tree gate valve under-pressure replacing device

Abstract

The utility model discloses a Christmas tree gate valve under-pressure replacement device which comprises an all-terrain vehicle, an under-pressure delivery mechanism detachably connected to the all-terrain vehicle and a temporary plugging mechanism detachably connected to the under-pressure delivery mechanism and used for temporarily plugging an oil pipe in a Christmas tree. Wherein the pressurized delivery mechanism can deliver the temporary plugging mechanism to a plugging position of an oil pipe in a Christmas tree. The device is reasonable in structure, convenient to use, high in safety and strong in practicability, can be used for safely replacing a faulty gate valve under pressure under the state of no production stop and no pressure relief, can recover the control and regulation functions of a Christmas tree in crude oil production in a short time, can effectively improve the production efficiency, and is suitable for popularization and application. And the production cost and the labor intensity of production workers are reduced. The Christmas tree gate valve replacing tool is suitable for replacing Christmas tree gate valves.

Description

Technical Field

[0001] The utility model relates to a pressure replacement device, in particular to a pressure replacement device for a Christmas tree gate valve. Background Art

[0002] The gate valve at the oil wellhead usually refers to the gate valve in the Christmas tree. The Christmas tree is a wellhead device used to extract oil in self-flowing wells and machine-extracted wells. It is the main equipment for controlling and regulating oil production at the top of the oil well. During the production process, the gate valve on the Christmas tree is prone to failures such as poor sealing and inflexible gate valve adjustment under the effects of fluid erosion, corrosion aging, high temperature and high pressure, which will cause oil spills and pollute the environment. In addition, when the gate valve cannot be closed, it is easy to induce a blowout accident, which will seriously affect the normal production of the oil well.

[0003] To avoid the above situation, when the gate valve on the Christmas tree in the oil production wellhead fails, it needs to be replaced in time. However, routine maintenance and replacement of the gate valve requires stopping production and releasing pressure, which will affect the progress of oil production and seriously affect production efficiency. Pressure release will pump a large amount of chemicals and water that have been injected into the well back into the tanker. After replacing the gate valve, a large amount of chemicals and water will be injected into the well again, which will increase a lot of workload, resulting in a long construction period, high production costs, and high labor intensity for production workers. Summary of the invention

[0004] In order to solve the above deficiencies in the prior art, the utility model aims to provide a pressure-replacing device for a Christmas tree gate valve, so as to achieve the purpose of improving production efficiency, reducing labor intensity of workers and reducing production costs.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is as follows: a pressure replacement device for a Christmas tree gate valve, comprising an all-terrain vehicle, a pressure delivery mechanism detachably connected to the all-terrain vehicle, and a temporary blocking mechanism detachably connected to the pressure delivery mechanism for temporarily blocking an oil pipe in the Christmas tree, wherein the pressure delivery mechanism can deliver the temporary blocking mechanism to a blocking position of the oil pipe in the Christmas tree.

[0006] As defined in the present utility model, the all-terrain vehicle includes a vehicle body, a plurality of hydraulic leg components fixed on the vehicle body and capable of limiting the position of the vehicle body, two hydraulic arm components fixed at intervals on one side of the vehicle body and capable of being folded, stored or unfolded, and two clamp components respectively fixed on the top of the two hydraulic arm components.

[0007] As a further limitation of the present invention, the pressurized delivery mechanism includes two first hydraulic cylinders and one second hydraulic cylinder; the first piston rods in the two first hydraulic cylinders are respectively detachably connected to two clamping members, the bottoms of the two first cylinder barrels in the two first hydraulic cylinders are each detachably connected to a clamping member, two limit rods are detachably connected between the two clamping members, and the two clamping members and the two limit rods cooperate with each other to firmly fix the two first hydraulic cylinders on the large four-way in the oil production tree; the second cylinder barrel in the second hydraulic cylinder is fixedly connected between the two first piston rods in the two first hydraulic cylinders through a mounting plate, and the second piston rod in the second hydraulic cylinder is detachably connected to the temporary blocking mechanism through a force transmission rod member, and a sealing member for sealing the oil production tree is sleeved on the outer side of the force transmission rod member.

[0008] As a further limitation of the present invention, the temporary blocking mechanism includes a shell having a cavity, a transmission shaft threadedly connected in the shell cavity, a bearing rotatably connected to the outside of the transmission shaft and fixedly connected to the bottom of the shell, a seating component slidably connected to the outside of the transmission shaft and located below the bearing, and a sealing component slidably connected to the outside of the transmission shaft and located below the seating component, wherein the top of the shell is detachably connected to the force transmission rod component.

[0009] As a further limitation of the present invention, the seating component includes a claw seat slidably connected to the outside of the transmission shaft, a plurality of claws hinged on the bottom circumference of the claw seat, and a sliding adjustment component slidably connected to the outside of the transmission shaft and capable of tilting the claws and expanding outward, wherein a return spring is fixed between the top of each claw and the claw seat, and shear nails are inserted between the sliding adjustment component and the transmission shaft.

[0010] As a further limitation of the present invention, the sealing component includes a skeleton seat slidably connected to the outside of the transmission shaft, a rubber cylinder skeleton hooked on the bottom end of the skeleton seat and slidably connected to the outside of the transmission shaft, a rubber cylinder fixed on the rubber cylinder skeleton and slidably connected to the outside of the transmission shaft, and a top ring fixed at the bottom end of the transmission shaft and located below the rubber cylinder.

[0011] As another limitation of the present invention, a monitor for monitoring oil leakage is threadedly connected to the bottom of the temporary plugging mechanism.

[0012] Due to the adoption of the above technical solution, the utility model has the following beneficial effects compared with the prior art:

[0013] (1) The utility model adopts a structural form that combines an all-terrain vehicle, a pressure delivery mechanism and a temporary plugging mechanism. The all-terrain vehicle can travel stably in various complex terrains and can quickly reach a designated location to replace a gate valve. The pressure delivery mechanism can deliver the temporary plugging machine to the plugging position of the oil pipe in the oil tree. The temporary plugging mechanism can temporarily plug the oil pipe in the oil tree. Under the condition of not stopping production and not releasing pressure, the utility model can be used to safely replace a faulty gate valve under pressure, and the control and regulation functions of the oil tree in crude oil production can be restored in a short time, which can effectively improve production efficiency, reduce production costs and reduce the labor intensity of production workers.

[0014] (2) The multiple hydraulic leg components on the all-terrain vehicle of the utility model can limit the position of the all-terrain vehicle after the all-terrain vehicle reaches the designated location, so that the all-terrain vehicle can be stably parked at the designated location. In addition, the hydraulic arm components on the all-terrain vehicle can be folded or unfolded, which is more convenient to use.

[0015] (3) The two first hydraulic cylinders and the second hydraulic cylinder on the pressure delivery mechanism of the utility model cooperate with each other to deliver the temporary plugging mechanism into the oil production tree. The second hydraulic cylinder can limit the temporary plugging component to prevent the temporary plugging component from moving upward, which can effectively improve the safety and reliability of the utility model.

[0016] (4) The utility model has a reasonable structure and good plugging effect. The seating component and the sealing component cooperate with each other to firmly limit the temporary plugging mechanism at a designated position in the Christmas tree and seal the oil pipe of the Christmas tree.

[0017] (5) The present invention is provided with a rubber cylinder frame, which can prevent the rubber cylinder from overturning when the lower pressure is too large, effectively prevent the setting failure, and further improve the safety and reliability of the present invention.

[0018] (6) The utility model is provided with a monitor which can detect oil leakage and help the staff to find the danger of oil leakage in time, thereby effectively improving the safety of the utility model.

[0019] In summary, the utility model has a reasonable structure, is easy to use, has high safety and is highly practical. The utility model can be used to replace a faulty gate valve safely under pressure without stopping production or releasing pressure, and can restore the control and regulation functions of the Christmas tree in crude oil production in a short time, which can effectively improve production efficiency, reduce production costs and reduce the labor intensity of production workers. The utility model is suitable for use when replacing the gate valve of the Christmas tree. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention is described in further detail below in conjunction with the accompanying drawings and specific embodiments.

[0021] Figure 1It is a schematic diagram of the structure of an embodiment of the utility model;

[0022] Figure 2 It is a structural schematic diagram of two hydraulic arm components in the all-terrain vehicle in an embodiment of the utility model in a folded and stored state;

[0023] Figure 3 It is a structural schematic diagram of two hydraulic arm components in an all-terrain vehicle in an embodiment of the utility model in an unfolded state;

[0024] Figure 4 It is a structural schematic diagram of the pressure delivery mechanism and the temporary blocking mechanism in the embodiment of the utility model;

[0025] Figure 5 It is a cross-sectional view of the pressure delivery mechanism and the temporary blocking mechanism in the embodiment of the utility model;

[0026] Figure 6 This is a structural schematic diagram of the temporary blocking mechanism in the embodiment of the utility model;

[0027] Figure 7 It is a cross-sectional view of the temporary blocking mechanism in the embodiment of the utility model;

[0028] Figure 8 for Figure 7 A magnified schematic diagram of part A;

[0029] Fig. 9 This is a schematic diagram of the use state of an embodiment of the utility model;

[0030] In the figure: 1, vehicle body; 2, hydraulic leg component; 3, hydraulic arm component; 4, clamp component; 5, first hydraulic cylinder; 6, clamping component; 7, limit rod; 8, second hydraulic cylinder; 9, sealing component; 10, force transmission rod component;

[0031] 11. Temporary blocking mechanism; 1101. Housing; 1102. Transmission shaft; 1103. Cylindrical cavity; 1104. Bearing; 1105. Claw seat; 1106. Return spring; 1107. Claw; 1108. Sliding adjustment member; 1109. Frame seat; 1110. Shear pin; 1111. Rubber cartridge frame; 1112. First rubber cartridge unit; 1113. Washer; 1114. Second rubber cartridge unit; 1115. Top ring; 1116. Monitor;

[0032] 12. Mounting plate; 13. Limit claw component; 14. Gate valve support plate; 15. Christmas tree; 16. Large four-way. DETAILED DESCRIPTION

[0033] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and understand the present invention, and are not used to limit the present invention.

[0034] Embodiment A device for replacing a gate valve of a Christmas tree under pressure

[0035] like Figure 1 As shown, this embodiment includes an all-terrain vehicle, a pressure delivery mechanism detachably connected to the all-terrain vehicle, and a temporary plugging mechanism 11 detachably connected to the pressure delivery mechanism for temporarily plugging the oil pipe in the oil tree 15, wherein the pressure delivery mechanism can deliver the temporary plugging mechanism 11 to the plugging position of the oil pipe in the oil tree 15.

[0036] like Figure 2 , Figure 3 As shown, the all-terrain vehicle includes a vehicle body 1, a plurality of hydraulic leg members 2 fixed on the vehicle body 1 and capable of limiting the position of the vehicle body 1, two hydraulic arm members 3 fixed at intervals on one side of the vehicle body 1 and capable of being folded, stored or unfolded, and two clamp members 4 respectively fixed on the top of the two hydraulic arm members 3. Specifically, in this embodiment, a total of four hydraulic leg members 2 are provided, the vehicle body 1 is an existing tracked vehicle, and the tracked vehicle can stably travel in various complex terrains. The hydraulic leg members 2 and the hydraulic arm members 3 are both existing structures, wherein the lifting height of the legs in each hydraulic leg member 2 can be adjusted so that the tracked vehicle can be stably parked on various complex terrains. When the tracked vehicle is moving, the legs in each hydraulic leg member 2 need to be lifted off the ground. When the tracked vehicle is moving, the hydraulic arm member 3 is in a folded and stored state. After the tracked vehicle moves to the designated place for replacing the gate valve, the hydraulic arm member 3 needs to be unfolded.

[0037] like Figure 4 , Figure 5As shown, the pressure delivery mechanism includes two first hydraulic cylinders 5 and a second hydraulic cylinder 8. The first piston rods in the two first hydraulic cylinders 5 are detachably connected to the two clamping members 4, respectively. The bottoms of the two first cylinder barrels in the two first hydraulic cylinders 5 are detachably connected to a clamping member 6, and two limit rods 7 are detachably connected between the two clamping members 6. The two clamping members 6 and the two limit rods 7 cooperate with each other to firmly fix the two first hydraulic cylinders 5 on the large four-way 16 in the oil production tree 15. Specifically, in this embodiment, the two clamping members 6 have the same structure, and the clamping member 6 includes a bottom plate detachably connected to the bottom of the first hydraulic cylinder 5, a mounting frame fixed at the bottom of the bottom plate, and a clamping plate fixed on the mounting frame. A limit rod 7 is detachably connected between the two sides of the two mounting frames, and the limit rod 7 includes a round rod and two threaded rods fixed at both ends of the round rod. The two threaded rods are each fixed at the corresponding positions of the two mounting frames by a nut. The second cylinder barrel in the second hydraulic cylinder 8 is fixedly connected between the two first piston rods in the two first hydraulic cylinders 5 through the mounting plate 12. The second piston rod in the second hydraulic cylinder 8 passes through the mounting plate 12 and is slidably connected to the mounting plate 12. The second piston rod in the second hydraulic cylinder 8 is detachably connected to the temporary blocking mechanism 11 through the force transmission rod member 10. When the force transmission rod member 10 is rotated, the force transmission rod member 10 can transmit the rotational force to the temporary blocking mechanism 11 so that the temporary blocking mechanism 11 can temporarily block the oil pipe in the Christmas tree 15 or release the temporary blocking of the oil pipe in the Christmas tree 15. The outer side of the force transmission rod member 10 is sleeved with a sealing member 9 for sealing the Christmas tree 15. The outer side of the sealing member 9 has a rotating hand wheel to facilitate the installation of the sealing member 9 on the Christmas tree 15. In order to improve the practicality of this embodiment, this embodiment has two limit claw components 13 that can be rotatably connected to the upper ends of the two first piston rods, and the two limit claw components 13 cooperate with each other to limit and fix the force transmission rod component 10 to prevent the force transmission rod component 10 from moving. Any one of the two first piston rods is rotatably connected to a gate valve support plate 14 that can be positioned and used to temporarily place the gate valve when replacing the gate valve.

[0038] like Figure 6-8As shown, the temporary blocking mechanism 11 includes a housing 1101 having a cavity, a transmission shaft 1102 threadedly connected in the cavity of the housing 1101, a bearing 1104 rotatably connected to the outside of the transmission shaft 1102 and fixedly connected to the bottom of the housing 1101, a seating component slidably connected to the outside of the transmission shaft 1102 and located below the bearing 1104, and a sealing component slidably connected to the outside of the transmission shaft 1102 and located below the seating component. Specifically, in this embodiment, the housing 1101 includes a cylinder having a cylindrical cavity 1103 and a hexagonal column fixedly arranged on the top of the cylinder, wherein the hexagonal column in the housing 1101 is detachably connected to the force transmission rod component 10. The seating component includes a claw seat 1105 slidably connected to the outside of the transmission shaft 1102, a plurality of claws 1107 hinged on the bottom circumference of the claw seat 1105, and a sliding adjustment component 1108 slidably connected to the outside of the transmission shaft 1102 and capable of tilting the claws 1107 and expanding outward, wherein a return spring 1106 is fixedly provided between the top of each claw 1107 and the claw seat 1105, and a shear nail 1110 is inserted between the sliding adjustment component 1108 and the transmission shaft 1102, and a total of two shear nails 1110 are provided in this embodiment. In this embodiment, a total of four claws 1107 are provided, and the four claws 1107 are arranged at equal intervals along the bottom circumference of the claw seat 1105. The sliding adjustment member 1108 is a bullet-shaped hollow member. The sliding adjustment member 1108 and the transmission shaft 1102 are fixed together by inserted shear nails 1110. When the sliding adjustment member 1108 moves upward, it can be inserted into the position between each claw 1107 and the transmission shaft 1102. At this time, each claw 1107 can be tilted and expanded outward. When the sliding adjustment member 1108 moves downward, it can leave the position between each claw 1107 and the transmission shaft 1102. At this time, each claw 1107 can be restored to a vertical state under the action of each return spring 1106. The sealing member includes a frame seat 1109 slidably connected to the outside of the transmission shaft 1102, a rubber cylinder frame 1111 hooked at the bottom of the frame seat 1109 and slidably connected to the outside of the transmission shaft 1102, a rubber cylinder fixed on the rubber cylinder frame 1111 and slidably connected to the outside of the transmission shaft 1102, and a top ring 1115 fixed at the bottom of the transmission shaft 1102 and located below the rubber cylinder. Specifically, the rubber cylinder frame 1111 includes a plurality of rubber cylinder frame units, which are arranged in sequence along the circumference of the bottom end of the frame seat 1109 to form a closed loop, and each rubber cylinder frame unit is hooked on the frame seat 1109. The rubber cylinder frame 1111 can expand as the rubber cylinder expands, and the rubber cylinder frame 1111 can always be firmly hooked on the frame seat 1109.The rubber cylinder includes a first rubber cylinder unit 1112, a gasket 1113 fixed at the bottom of the first rubber cylinder unit 1112, and a second rubber cylinder unit 1114 fixed at the bottom of the gasket 1113. The upper end of the first rubber cylinder unit 1112 is fixedly connected to the rubber cylinder frame 1111, wherein the first rubber cylinder unit 1112 and the second rubber cylinder unit 1114 are both made of fluororubber material. It should be supplemented that when the present embodiment is actually used, it is necessary to seal the temporary blocking mechanism 11 in the oil pipe under the corresponding gate valve according to the position of the gate valve in the Christmas tree 15 to temporarily block the gate valve to be replaced and the oil pipe passage, and then the gate valve can be normally replaced.

[0039] In order to improve the safety and practicality of the utility model, in this embodiment, a monitor 1116 for monitoring oil leakage is threadedly connected to the bottom of the temporary plugging mechanism 11. Specifically, the monitor 1116 is threadedly connected to the bottom of the transmission shaft 1102. The monitor 1116 is an existing device that can monitor the pressure in the well in real time to prevent blowouts caused by excessive pressure.

[0040] like Fig. 9 As shown, the method of replacing the gate valve in the Christmas tree 15 under pressure using this embodiment is as follows:

[0041] 1. Drive the all-terrain vehicle to the designated location for repairing the gate valve, find a suitable parking position, park the vehicle, and adjust the four hydraulic outrigger components 2 so that the four hydraulic outrigger components 2 are stably supported on the ground.

[0042] Second, the sealing member 9 is removed and installed on the Christmas tree 15, and then the two hydraulic arm members 3 are unfolded, and then the two clamping members 6 are clamped at the position of the large four-way 16 in the Christmas tree 15, and the two first hydraulic cylinders 5 are stably fixed on the Christmas tree 15 through the two limit rods 7, and then the two first piston rods are removed from the two clamp members 4. At this time, the pressure delivery mechanism and the temporary blocking mechanism 11 are separated from the all-terrain vehicle. At this time, the all-terrain vehicle is no longer in effect, and the staff can drive the all-terrain vehicle away as needed.

[0043] 3. Start the two first hydraulic cylinders 5 to make the two first piston rods in the two first hydraulic cylinders 5 move downward, the two first piston rods move downward to drive the second hydraulic cylinder 8 to move downward, the second hydraulic cylinder 8 moves downward to drive the temporary plugging mechanism 11 to move downward, until the temporary plugging mechanism 11 is delivered to the position in the oil pipe of the Christmas tree 15 that needs to be blocked.

[0044] Fourth, remove the second piston rod from the top of the force transmission rod component 10, and then use a wrench to rotate the top of the force transmission rod component 10 to move the transmission shaft 1102 upward until the temporary blocking mechanism 11 is completely seated. Specifically, the rotation of the force transmission rod member 10 can drive the shell 1101 in the temporary plugging mechanism 11 to rotate, and the rotation of the shell 1101 can drive the top of the transmission shaft 1102 to move upward along the cylindrical cavity 1103 in the shell 1101. The upward movement of the transmission shaft 1102 can drive the sliding adjustment member 1108, the skeleton seat 1109, the rubber cylinder skeleton 1111, the rubber cylinder, the top ring 1115 and the monitor 1116 to move upward together. When the sliding adjustment member 1108 moves upward, it can be inserted into the position between each claw 1107 and the transmission shaft 1102. At this time, each claw 1107 can be tilted and expanded outward, and the claw 1107 can be smoothly attached to the inner wall of the oil pipe in the oil tree 15 and complete the seat. At this time, the temporary plugging mechanism 11 can be firmly fixed on the inner wall of the oil pipe in the oil tree 15.

[0045] 5. Continue to use a wrench to rotate the top of the force transmission rod member 10 to move the transmission shaft 1102 upward until the temporary plugging mechanism 11 is set. Specifically, the rotation of the force transmission rod member 10 can drive the transmission shaft 1102 to move upward. After the temporary plugging mechanism 11 is set, when the transmission shaft 1102 continues to move upward, the shear nails 1110 inserted between the sliding adjustment member 1108 and the transmission shaft 1102 will be cut off under the action of the shear force. At this time, the top ring 1115 continues to move upward under the drive of the transmission shaft 1102. The top ring 1115 compresses the rubber cylinder to make the rubber cylinder expand radially and close to the wall of the oil pipe. At this time, the oil pipe is effectively blocked and the setting is completed.

[0046] Sixth, start the second hydraulic cylinder 8 to make the second piston rod press against the top of the force transmission rod member 10, and then close the second hydraulic cylinder 8. At this time, the second piston rod plays a role in limiting the temporary blocking member to prevent the temporary blocking mechanism 11 from moving upward. After that, the faulty gate valve can be replaced.

[0047] After the gate valve in the Christmas tree 15 is replaced, the temporary plugging mechanism 11 and the force transmission rod member 10 in this embodiment need to be taken out from the Christmas tree 15, and then the sealing member 9 is removed from the Christmas tree 15, and then the temporary plugging mechanism 11, the force transmission rod member 10, and the sealing member 9 are assembled on the pressure delivery mechanism, and then the two clamping members 6 and the two limit rods 7 are removed from the Christmas tree 15 and assembled on the pressure delivery mechanism again, and finally the pressure delivery mechanism is assembled on the all-terrain vehicle, after which the all-terrain vehicle can be driven to other places that need maintenance to replace the gate valve. When the temporary plugging mechanism 11 and the force transmission rod member 10 in this embodiment are taken out from the Christmas tree 15, it is only necessary to reverse the corresponding steps in the above-mentioned method for replacing the gate valve in the Christmas tree 15 under pressure, so it will not be repeated here. Here, only the principle of unblocking and unjamming of the temporary blocking mechanism 11 is explained. The reverse rotation of the force transmission rod component 10 can drive the transmission shaft 1102 to move downward, and the corresponding rubber cylinder rebounds due to its own tension to complete the unblocking. Then, the sliding adjustment component 1108 moves downward and leaves the position between each claw 1107 and the transmission shaft 1102. Under the action of the reset spring 1106, each claw 1107 contracts inward to complete the unblocking.

[0048] It should be noted that the above is only a preferred embodiment of the utility model and is not intended to limit the utility model. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A pressure replacement device for a Christmas tree gate valve, characterized in that: The invention comprises an all-terrain vehicle, a pressure delivery mechanism detachably connected to the all-terrain vehicle, and a temporary plugging mechanism detachably connected to the pressure delivery mechanism for temporarily plugging the oil pipe in the oil tree, wherein the pressure delivery mechanism can deliver the temporary plugging mechanism to the plugging position of the oil pipe in the oil tree.

2. The device for replacing a gate valve of a Christmas tree under pressure according to claim 1, characterized in that: The all-terrain vehicle comprises a vehicle body, a plurality of hydraulic leg components fixed on the vehicle body and capable of limiting the position of the vehicle body, two hydraulic arm components fixed at intervals on one side of the vehicle body and capable of being folded, stored or unfolded, and two clamp components respectively fixed on the top of the two hydraulic arm components.

3. The device for replacing a gate valve of a Christmas tree under pressure according to claim 2, characterized in that: The pressure delivery mechanism includes two first hydraulic cylinders and one second hydraulic cylinder; the first piston rods in the two first hydraulic cylinders are detachably connected to the two clamping members respectively, the bottoms of the two first cylinder barrels in the two first hydraulic cylinders are detachably connected to a clamping member, two limit rods are detachably connected between the two clamping members, and the two clamping members and the two limit rods cooperate with each other to firmly fix the two first hydraulic cylinders on the large four-way in the oil production tree; the second cylinder barrel in the second hydraulic cylinder is fixedly connected between the two first piston rods in the two first hydraulic cylinders through a mounting plate, and the second piston rod in the second hydraulic cylinder is detachably connected to the temporary blocking mechanism through a force transmission rod member, and a sealing member for sealing the oil production tree is sleeved on the outer side of the force transmission rod member.

4. The device for replacing a gate valve of a Christmas tree under pressure according to claim 3, characterized in that: The temporary blocking mechanism includes a shell with a cavity, a transmission shaft threadedly connected in the shell cavity, a bearing rotatably connected to the outside of the transmission shaft and fixedly connected to the bottom of the shell, a seating component slidably connected to the outside of the transmission shaft and located below the bearing, and a sealing component slidably connected to the outside of the transmission shaft and located below the seating component, wherein the top of the shell is detachably connected to the force transmission rod component.

5. The device for replacing a gate valve of a Christmas tree under pressure according to claim 4, characterized in that: The seating component includes a claw seat slidably connected to the outside of the transmission shaft, a plurality of claws hinged on the bottom circumference of the claw seat, and a sliding adjustment component slidably connected to the outside of the transmission shaft and capable of tilting the claws and expanding outward, wherein a return spring is fixed between the top of each claw and the claw seat, and shear nails are inserted between the sliding adjustment component and the transmission shaft.

6. The device for replacing a gate valve of a Christmas tree under pressure according to claim 4, characterized in that: The sealing component includes a skeleton seat slidably connected to the outside of the transmission shaft, a rubber cylinder skeleton hooked on the bottom end of the skeleton seat and slidably connected to the outside of the transmission shaft, a rubber cylinder fixed on the rubber cylinder skeleton and slidably connected to the outside of the transmission shaft, and a top ring fixed at the bottom end of the transmission shaft and located below the rubber cylinder.

7. A Christmas tree gate valve under pressure replacement device according to any one of claims 1 to 6, characterized in that: The bottom thread connection of the temporary plugging mechanism is provided with a monitor for monitoring oil leakage.

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