Oil tubing cutter for oil and water well workover

Abstract

This utility model discloses a tubing cutting device for oil and water well workover. The device includes a rotary actuator, a cutting body fixedly connected to the rotary actuator, and a cutting blade and a retraction mechanism mounted on the cutting body. This device uses magnetic force to control the retraction of the cutting blade, reducing the probability of the cutting blade getting stuck and minimizing economic losses caused by the cutter malfunctioning due to jamming.

Description

Technical Field

[0001] This utility model relates to the technical field of equipment for oil and water well repair operations in oilfields, specifically to a tubing cutting device for oil and water well repair operations. Background Technology

[0002] In stratified oil and water injection wells, downhole tools such as packers, water distributors, and electric submersible pumps are installed. When these tools become stuck during well workover operations, they must first be left in the well, the tubing above them removed, and then a milling tool installed to complete the well workover. Removing the tubing above the downhole tools requires using a tubing cutter, and this can only be done using an internal cutting method. The tubing's inner diameter is generally small, making it challenging to design a cutter for such a small diameter.

[0003] Existing tubing cutters typically use a spring-loaded return mechanism. However, due to limited space and spring force, the performance of currently designed tubing cutters is unsatisfactory. Sometimes they cannot open to the required cutting size, rendering them unusable; other times they fail to retract after operation, becoming stuck in the tubing string. These problems prevent proper well repairs and cause significant economic losses to the oilfield. Utility Model Content

[0004] The purpose of this invention is to provide a tubing cutting device for oil and water well workover, which solves the problem in the prior art where the limited elasticity of the spring causes it to get stuck and unable to work properly when opening and retracting.

[0005] The technical solution adopted by this utility model is that the tubing cutting device for oil and water well repair includes a rotary device, a cutting body is fixedly connected to the rotary device, and a cutting blade and a retraction mechanism are installed on the cutting body.

[0006] The features of this utility model also include: The cutting body includes a cutting tube, one end of which is fixed with a sealing plug, and the other end of which is equipped with a cutter.

[0007] The cutting body includes a cutting tube, a magnet is fixed inside the cutting tube, a sealing plug is fixed at one end of the cutting tube, and a cutter is installed at the other end of the cutting tube.

[0008] The rotator includes a rotating tube with a cone fixed to one end. A cutting tube passes through the two side walls of the rotating tube and is fixed to the rotating tube. The inside of the cutting tube is connected to the inside of the rotating tube.

[0009] The shrinking mechanism includes a magnet fixed to the middle of the cutting tube, and a magnetic block on the cutter that cooperates with and attracts the magnet.

[0010] The cutter includes a piston, which is coaxial with the cutting tube. The diameter of the piston is the same as the inner diameter of the cutting tube. A magnetic block is fixed to the side of the piston near the magnet. The blade body is fixed to the side of the piston away from the magnetic block, and the blade edge of the blade body is located on the side away from the piston.

[0011] The inner wall of the cutting tube near the blade body is provided with a blocking step to limit the range of movement of the cutter.

[0012] A sealing ring is installed between the piston and the cutting tube.

[0013] The rotating tube and the cutting tube are perpendicular to each other.

[0014] The beneficial effects of this utility model are: This device uses magnetic force to control the retraction of the cutter, which can reduce the probability of the cutter getting stuck and reduce the economic losses caused by the cutter being stuck and unable to work properly. Attached Figure Description

[0015] Figure 1 This is an overall structural diagram of the present invention.

[0016] In the diagram: 1. Rotator; 101. Rotating tube; 102. Cone; 2. Cutting body; 201. Cutting tube; 202. Sealing plug; 203. Blocking step; 3. Retraction mechanism; 301. Magnet; 302. Magnetic block; 4. Cutting blade; 401. Piston; 402. Blade body. Detailed Implementation

[0017] The following detailed description is provided in conjunction with specific implementation methods.

[0018] The oil tubing cutting device for oil and water well workover of this utility model includes a rotary device 1, a cutting body 2 fixedly connected to the rotary device 1, and a retraction mechanism 3 and a cutting blade 4 installed on the cutting body 2.

[0019] The shrinking mechanism 3 includes a magnet 301 fixed inside the cutting body 2, and the cutter 4 is provided with a magnetic block 302 that cooperates with and attracts the magnet 301.

[0020] The cutting body 2 includes a cutting tube 201, a magnet 301 fixed inside the cutting tube 201, a sealing plug 202 fixed at one end of the cutting tube 201, and a cutter 4 installed at the other end of the cutting tube 201.

[0021] The rotator 1 includes a rotating tube 101, a cone 102 fixedly connected to one end of the rotating tube 101, and a cutting tube 201 passing through the two side walls of the rotating tube 101 and fixedly connected to the rotating tube 101. The interior of the cutting tube 201 is connected to the interior of the rotating tube 101.

[0022] The cutter 4 includes a piston 401, which is coaxial with the cutting tube 201. The diameter of the piston 401 is the same as the inner diameter of the cutting tube 201. A magnetic block 302 is fixed to the side of the piston 401 near the magnet 301. A blade body 402 is fixed to the side of the piston 401 away from the magnetic block 302. The blade edge of the blade body 402 is located on the side away from the piston 401.

[0023] The inner wall of the cutting tube 201 near the blade body 402 is provided with a blocking step 203 to limit the movement range of the cutter 4.

[0024] A sealing ring is installed between piston 401 and cutting tube 201.

[0025] The rotating tube 101 and the cutting tube 201 are perpendicular to each other.

[0026] Example 1 The oil tubing cutting device for oil and water well repair of this utility model includes a rotary device 1, a cutting body 2 fixedly connected to the rotary device 1, and a cutting blade 4 and a retraction mechanism 3 installed on the cutting body 2.

[0027] This application has the following advantages: 1. High operating efficiency: The rotary unit 1 can drive the cutting body 2 and the cutting blade 4 to rotate at high speed and stably, enabling the cutting blade 4 to quickly act on the tubing wall, significantly shortening the cutting time of a single tubing. In scenarios involving continuous cutting of multiple tubings, it can effectively reduce the overall well workover cycle, reduce production losses caused by well shutdowns, and buy more time for subsequent operations.

[0028] 2. The cut quality is good. The shrinkage mechanism 3 can control the shrinkage of the cutter 4, so that the cutter 4 can always maintain a stable feed and cutting angle during cutting. The cut end face of the oil pipe after cutting has a high degree of flatness, which lays a good foundation for subsequent oil pipe retrieval, docking or replacement operations, and saves the secondary processing process.

[0029] 3. Convenient operation: The retraction mechanism 3 controls the retraction of the cutter 4, eliminating the need for operators to go down into the well. Operators can control the extension length, cutting speed, and rotation frequency of the cutter 4 from the operator's perspective. This not only reduces the labor intensity of operators but also minimizes manual intervention. Even inexperienced personnel can master the operation after simple training.

[0030] 4. Strong environmental adaptability: It can be adapted to different well types and tubing materials and inner diameters by replacing the appropriate cutter 4 and adjusting the rotation speed of the rotator 1 and the extension stroke of the retraction mechanism 3. It can operate stably under various complex well conditions, improving the versatility and reusability of the device.

[0031] Example 2 Based on Embodiment 1, the cutting body 2 of this application includes a cutting tube 201, one end of which is fixedly connected to a sealing plug 202, and the other end of which is equipped with a cutter 4.

[0032] The cutting body 2 adopts a cutting tube 201 structure. The tubular shape itself is highly rigid, providing stable support for the cutting blade 4 at the end and preventing the cutting blade 4 from shaking or shifting due to force during the cutting process. At the same time, the cutting tube 201 can form a circumferential constraint on the cutting blade 4, ensuring that the cutting blade 4 always cuts the oil pipe along a preset circumferential trajectory, ensuring a flat and regular cutting surface, and providing a basic condition for the smooth progress of subsequent well workover procedures.

[0033] The design of blocking one end of the cutting pipe 201 can effectively prevent impurities such as mud and sand from entering the device, avoiding wear of the cutting blade 4 or affecting the flexible operation of the internal retraction mechanism 3. The other end is equipped with the cutting blade 4, so that the working end of the cutting blade 4 extends outward and the non-working parts are concealed inside, reducing the impact damage between the cutting blade 4 and the well wall or other parts when it is not in operation, and extending the service life of the cutting blade 4 and its internal components.

[0034] The tubular structure of the cutting tube 201 can directly serve as the mounting carrier for core components such as the cutter 4 and the retraction mechanism 3. Its internal space can neatly accommodate all components without the need for an additional complex installation frame, making the overall structure of the device more compact. Within the limited space downhole, this facilitates the raising and lowering of the device and reduces the probability of interference with other components in the well.

[0035] Example 3 Based on Embodiment 2, the rotator 1 of this application includes a rotating tube 101, a cone 102 fixedly connected to one end of the rotating tube 101, and a cutting tube 201 passing through both side walls of the rotating tube 101 and fixedly connected to the rotating tube 101. The interior of the cutting tube 201 is in communication with the interior of the rotating tube 101.

[0036] As the core component of the rotator 1, the rotating tube 101 can stably output rotational power, and the cutting tube 201 is fixed to its two side walls, which can directly and evenly transmit the rotational power to the cutting tube 201 and the end cutter 4, ensuring that the cutter 4 rotates and cuts continuously and stably, avoiding the decrease in cutting efficiency caused by power loss, and helping to quickly complete the oil pipe cutting operation.

[0037] Enhance overall structural stability and ensure cutting accuracy: The cutting tube 201 and the rotating tube 101 are fixedly connected and interconnected, forming a stable whole and reducing the loosening or displacement of components during the cutting process.

[0038] The cone 102 structure at one end of the rotating tube 101 can play a guiding role downhole, preventing the device from shifting position due to the well environment during rotating cutting, ensuring that the cutter 4 always cuts along the preset trajectory, and ensuring that the cut surface is flat and regular.

[0039] The structure in which the cutting tube 201 is connected to the rotating tube 101 can form an internal fluid channel for hydraulic drive. High-pressure fluid can smoothly enter the cutting tube 201 through the rotating tube 101 and act on the cutter 4, fixing the cutter 4 to the outside of the cutting tube 201.

[0040] The cone 102 structure not only has a guiding function, but also reduces friction and collision with the well wall when the device is being pulled up or down the well, thus reducing the risk of stuck drill bit. The stable connection and communication design between the cutting pipe 201 and the rotating pipe 101 makes the overall structure of the device compact, more adaptable in the limited space downhole, reduces the possibility of interference with other downhole components, and ensures operational safety.

[0041] Example 4 Based on Embodiment 3, the shrinkage mechanism 3 of this application includes a magnet 301 fixed to the middle of the cutting tube 201, and a magnetic block 302 on the cutter 4 that cooperates with and attracts the magnet 301.

[0042] The magnetic control method offers rapid response, driving the cutter 4 to quickly retract into the cutting tube 201 without the need for complex mechanical transmissions, thus reducing operational delays. Especially in complex downhole environments, it can instantly control the retraction state of the cutter 4 according to operational needs, avoiding prolonged exposure of the cutter 4 and improving the device's adaptability to operational rhythms.

[0043] Magnetic control eliminates the need for hydraulic lines, gears, and other easily worn components, reducing the complexity of the mechanism. The absence of redundant transmission components within the cutting tube 201 reduces friction and jamming between parts, lowers the risk of the cutter 4 failing to retract due to mechanical failure, and improves the reliability and service life of the retraction mechanism 3.

[0044] Magnetic control requires no electric drive or chemical assistance and is unaffected by the high temperature and high pressure environment downhole, enabling stable retraction of the cutter. Furthermore, the operation process requires no disassembly or adjustment of the device, avoiding downhole safety accidents caused by manual intervention and improving operational safety under harsh conditions.

[0045] Example 5 Based on Embodiment 4, the cutter 4 of this application includes a piston 401, which is coaxial with the cutting tube 201. The diameter of the piston 401 is the same as the inner diameter of the cutting tube 201. A magnetic block 302 is fixed to the side of the piston 401 near the magnet 301. A blade body 402 is fixed to the side of the piston 401 away from the magnetic block 302. The blade edge of the blade body 402 is located on the side away from the piston 401.

[0046] The magnetic block 302 at the end of piston 401 away from cutter body 402 cooperates with magnet 301 to precisely convert magnetic force into linear motion power for piston 401, driving piston 401 to slide smoothly within cutting tube 201, thereby causing cutter body 402 to retract. Magnetic force transmission is direct and without mechanical loss, avoiding power transmission deviation and ensuring that cutter body 402 always moves along a preset trajectory, guaranteeing uniform force during cutting and improving the flatness of the cut surface.

[0047] Optimized component layout and enhanced protection: The blade body 402 and the magnetic block 302 are located on both sides of the piston 401, forming an orderly layout within the cutting tube 201, avoiding mutual interference between components. The design of the magnetic block 302 being far from the blade body 402 prevents metal debris generated during cutting from wearing down the magnetic block 302, ensuring the stability of the magnetic force. At the same time, the piston 401 can isolate impurities when moving within the cutting tube 201, reducing contamination of the magnetic block 302 and the blade body 402, and extending their service life.

[0048] To improve cutting safety and reduce the risk of malfunction: The piston 401 moves within the enclosed space of the cutting tube 201, preventing external impurities from jamming the moving parts and reducing the risk of malfunctions in the extension and retraction of the cutter body 402. Furthermore, when the cutter body 402 retracts, the piston 401 can drive it completely into the cutting tube 201. The magnetic block 302 is separated from the cutter body 402 by the piston 401, protecting the cutter body 402 from impacts and preventing the magnetic block 302 from being affected by cutting impacts, thus reducing the probability of accidents during downhole operations.

[0049] Example 6 Based on Embodiment 5, the inner wall of the cutting tube 201 of this application near the blade 402 is provided with a blocking step 203 for limiting the movement range of the cutter 4.

[0050] The blocking step 203 forms a protruding structure at the end of the cutting tube 201 near the cutter 4, which can directly and rigidly limit the movement range of the piston 401 and the cutter body 402. When the piston 401 drives the cutter body 402 to extend outward from the cutting tube 201, the step can prevent the piston 401 from moving forward further, avoiding the piston 401 and the cutter body 402 from detaching from the cutting tube 201 as a whole due to abnormal conditions, ensuring that the cutter 4 always remains connected to the main body of the device, and preventing the components from falling off and causing downhole operation failures.

[0051] By limiting the movement of the blocking step 203, the extension and retraction of the cutter 4 are always within a controllable range, preventing the piston 401 from increasing the clearance between itself and the cutting tube 201 after long-term reciprocating motion, which could cause the cutter body 402 to loosen or shift during cutting vibration. This further ensures the relative position stability of the cutter 4 and the cutting tube 201, reducing the impact of the potential for the cutter 4 to come off on the overall operation of the device.

[0052] If the cutter 4 detaches, it will not only interrupt the operation but may also cause serious problems such as stuck drill bit and component damage. The blocking step 203 completely avoids this risk structurally, ensuring that the cutter 4 is always under control during the cutting and retraction process, ensuring that the operation proceeds as planned, while reducing the probability of downhole safety accidents caused by component detachment and improving the reliability of the equipment operation.

[0053] Example 7 Based on Embodiment Six, the piston 401 and the cutting tube 201 of this application are sealed by a sealing ring.

[0054] The sealing ring forms a tight barrier between the piston 401 and the cutting tube 201, preventing impurities such as mud, sand, and metal fragments from entering the cutting tube 201. This avoids impurities adhering to the magnetic block 302, the moving surface of the piston 401, or the connection point of the cutter body 402, preventing magnetic failure, piston 401 jamming, or cutter body 402 extension / retraction malfunction, ensuring the normal operation of the cutter 4 and the retraction mechanism 3, and extending the service life of the components.

[0055] This device uses hydraulically driven piston 401 to move. The sealing ring effectively prevents fluid leakage from the gap between piston 401 and cutting tube 201, ensuring stable pressure inside cutting tube 201. Stable pressure can push piston 401 to slide at a uniform speed, allowing the blade 402 to extend or retract smoothly, avoiding problems such as insufficient power and uneven cutting force caused by pressure loss, thus ensuring cutting accuracy and efficiency.

[0056] The sealing ring fills the gap between the piston 401 and the cutting tube 201, reducing the loss caused by direct friction between the two. At the same time, the sealing ring itself has lubricating properties, which can reduce the resistance during the reciprocating motion of the piston 401, prevent scratches and deformation of the inner wall of the piston 401 or the cutting tube 201 caused by friction, improve the sealing performance and durability of the fit between the two, and reduce the probability of device failure.

[0057] The sealing ring can withstand high temperatures, high pressures, and corrosive environments downhole, maintaining its sealing performance over a long period without aging or cracking due to harsh working conditions. This ensures that the interior of the cutting pipe 201 remains sealed in complex downhole environments, preventing safety hazards caused by impurities and guaranteeing stable power transmission, thus supporting the safe advancement of cutting operations.

[0058] Example 8 Based on Embodiment 7, the rotating tube 101 and the cutting tube 201 of this application are perpendicular to each other.

[0059] The rotating tube 101 is perpendicular to the cutting tube 201, allowing the rotational power of the rotating tube 101 to be transmitted perpendicularly to the cutting tube 201 and the cutter 4. This causes the cutter 4 to generate a uniform radial cutting force around the circumference of the oil pipe. During the cutting process, the force direction of the cutter 4 is perpendicular to the axis of the oil pipe, avoiding skewness of the cutting surface caused by force offset, ensuring a flat and regular cutting surface, and reducing wear on the cutter 4 caused by uneven force, thus extending the service life of the cutter 4.

[0060] The vertical structure makes the overall shape of the device more compact, and the cutting tube 201 can extend radially along the rotating tube 101 without occupying additional axial space. In the narrow tubing environment downhole, it can effectively avoid collisions with the well wall and the inner wall of the tubing, reduce the risk of interference when raising and lowering the device, and at the same time facilitate the precise alignment of the cutter 4 with the cutting position in a limited space, improving the device's adaptability to complex downhole spaces.

[0061] The vertical connection method ensures more balanced force distribution at the connection point between the rotating tube 101 and the cutting tube 201, resulting in a shorter and more direct power transmission path and reducing power loss during transmission. When the rotating tube 101 rotates, it simultaneously drives the cutting tube 201 and the cutter 4 to rotate stably, avoiding power lag or fluctuations caused by improper connection angles. This ensures that the cutter 4 maintains a stable rotation speed, quickly completing the tubing cutting operation and shortening cutting time.

[0062] The vertical connection forms a stable "T" or "L" shaped structure between the rotating tube 101 and the cutting tube 201, resulting in a stronger load-bearing capacity at the connection point. The reaction force generated during the cutting process can be evenly distributed to the rotating tube 101 through the vertical structure, avoiding component deformation or loosening caused by excessive local stress, reducing failures such as the cutting tube 201 falling off and the cutter 4 shifting, and improving the overall reliability of the device.

Claims

1. A tubing severing device for use in workover of oil and water wells, characterized in that Includes a rotator (1), on which a cutting body (2) is fixedly connected, and on which a cutter (4) and a retraction mechanism (3) are mounted. The cutting body (2) includes a cutting tube (201), one end of which is fixedly connected to a sealing plug (202), and the other end of which is equipped with a cutter (4). The shrinking mechanism (3) includes a magnet (301) fixed to the middle of the cutting tube (201), and the cutter (4) is provided with a magnetic block (302) that cooperates with and attracts the magnet (301).

2. The tubing cutting device for oil and water well workover according to claim 1, characterized in that, The rotator (1) includes a rotating tube (101), one end of which is fixedly connected to a cone (102). The cutting tube (201) passes through both sides of the rotating tube (101) and is fixedly connected to the rotating tube (101). The interior of the cutting tube (201) is connected to the interior of the rotating tube (101).

3. The tubing cutting device for oil and water well workover according to claim 1, characterized in that, The cutter (4) includes a piston (401), which is coaxial with the cutting tube (201). The diameter of the piston (401) is the same as the inner diameter of the cutting tube (201). The magnetic block (302) is fixed to the side of the piston (401) near the magnet (301). The blade body (402) is fixed to the side of the piston (401) away from the magnetic block (302). The blade edge of the blade body (402) is located on the side away from the piston (401).

4. The tubing cutting device for oil and water well workover according to claim 3, characterized in that, The inner wall of the cutting tube (201) near the blade body (402) is provided with a blocking step (203) to limit the movement range of the cutter (4).

5. The tubing cutting device for oil and water well workover according to claim 3, characterized in that, A sealing ring is installed between the piston (401) and the cutting tube (201).

6. The tubing cutting device for oil and water well workover according to claim 2, characterized in that, The rotating tube (101) and the cutting tube (201) are perpendicular to each other.

Images