A downhole pressure dynamic monitoring dismounting tool

Abstract

At present, the main yield of southwest oil and gas field is derived from high pressure sulfur block, but due to the harsh downhole environment of the block, the coverage of long period dynamic monitoring of the block is extremely low, because the dynamic monitoring is still carried out by using the traditional pressure build-up technology, and the equipment and personnel need to be on duty in the well site for a long time, the labor intensity is large, the work efficiency is low, the monitoring cost is high, and at the same time, for the equipment to withstand high temperature, high pressure and high sulfur environment for a long time, there is a great safety risk. In view of this, the purpose of the present application is to develop a pressure gauge unhooking tool suitable for high pressure sulfur gas well, which can place the pressure gauge in the well for a long time to monitor the pressure. The whole monitoring process only needs 2 days of operation time for launching and fishing, which fundamentally reduces the operation cost, relieves the labor intensity of employees, improves the utilization rate of well testing equipment, and reduces the safety risks such as blowout prevention system leakage, wire corrosion and the like.

Description

Technical Field

[0001] This invention belongs to the technical field of gas well dynamic monitoring devices, specifically relating to a downhole pressure dynamic monitoring and uncoupling tool for high-pressure sulfur-containing gas wells. The uncoupling tool consists of a pressure gauge monitoring device mounted on a release device, which is lowered into the well to perform dynamic pressure monitoring. It also provides a matching delivery device and a retrieval device. Background Technology

[0002] From 2014 to 2019, the Chuanzhong Oil and Gas Field conducted 4,237 well tests of various types. The data provided by these tests offered insights into reservoir engineering characteristics, dynamic features, and well production organization, resulting in a wealth of research findings. However, of the planned 556 well tests (including production capacity tests, pressure reduction tests, pressure recovery tests, and interference tests) from 2014 to 2019, only 344 were actually completed, achieving a completion rate of 61.87%. Simultaneously, conventional well tests on high-pressure, high-sulfur wells were planned for 705 times over these six years, with only 526 actually completed, achieving a completion rate of 74.61%. One of the main reasons for the low completion rate is the heavy workload and insufficient equipment. The well testing team currently has only two vehicle crews capable of conducting conventional well tests on high-pressure, high-sulfur wells, and these two crews also handle over 90% of the oil and gas field's production capacity tests, pressure reduction tests, and pressure recovery tests. Currently, the main production of the Southwest Oil and Gas Field comes from high-pressure sulfur-containing blocks. However, due to the harsh downhole environment of these blocks, the coverage of long-term dynamic monitoring is extremely low. This is because dynamic monitoring still uses traditional pressure well testing technology, which requires equipment and personnel to stay at the well site for a long time. This results in high labor intensity, low work efficiency, and high monitoring costs. At the same time, there are significant safety risks for equipment that has to withstand high temperature, high pressure, and high sulfur content environments for extended periods.

[0003] If a new type of safe and reliable mechanical detachment tool for pressure gauges, which utilizes wire ropes for deployment and retrieval, can be developed, allowing the pressure gauges to be placed in the well for extended periods to collect data, pressure monitoring costs can be reduced. This would also save significant manpower and resources, enabling well testing teams to complete more conventional well tests on high-pressure, high-sulfur wells using their 105MPa and 70MPa units. This would allow for better utilization of well testing equipment, improve the completion rate of well testing in oil and gas fields, and provide more fundamental data for oil and gas production and development and dynamic monitoring of oil and gas reservoirs in central Sichuan. Summary of the Invention

[0004] In view of this, the purpose of this invention is to develop a pressure gauge detachment tool suitable for high-pressure sulfur-containing gas wells, which allows the pressure gauge to be placed in the well for a long time for pressure monitoring.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0006] First, a detachment device is designed, comprising a detachment cylinder. Inside the detachment cylinder is an axially movable retrieval rod. The retrieval rod has an L-shaped groove on its side wall. A fixing pin is located inside the detachment cylinder within the L-shaped groove. The top of the retrieval rod extends out of the detachment cylinder and has a retrieval head. The retrieval head is a frustum-shaped cone, wider at the bottom than the top, and has a torsion section at its top. Inside the detachment cylinder is an axially movable anchoring rod. The top of the anchoring rod is axially rotatably connected to the bottom of the retrieval rod. The anchoring rod is in contact with a first compression spring under downward force. The bottom of the anchoring rod extends out of the detachment cylinder and has a pressure gauge mounting section. The detachment device also includes mutually hinged anchoring claws and a connecting rod. The anchoring claws are also hinged to the anchoring rod, and the connecting rod is also hinged to the detachment cylinder. An anchoring claw extension hole is provided on the detachment cylinder. The release device also includes a locking block, which is hinged to the release cylinder. The release cylinder has a locking block extension hole, and the inner side of the locking block is in contact with the second compression spring under upward force.

[0007] The developed electronic release device must be able to be smoothly lowered to a designated location using a steel wire rope. Upon electric triggering, the outer diameter of the release device rapidly increases, locking onto the inner wall of the gas well tubing. The steel wire rope is then retrieved, leaving the release device and pressure gauge downhole. After testing, a special tool is used for retrieval with the steel wire rope. The structure used for anchoring to the inner wall of the tubing employs three anchoring claws, not anchoring the entire circumference, thus avoiding interference with the flow of fluid within the tubing. The anchoring claws utilize a linkage mechanism, relying on springs for energy storage. Upon reaching the trigger condition, the spring force is released, causing the anchoring claws to expand from the retracted state, completing the anchoring action.

[0008] As a preferred design for the decoupling device, three anchoring claws are evenly distributed along the circumference at the same height position on the decoupling cylinder. Two sets of anchoring claws are provided along the length of the decoupling cylinder, and the tooth profiles of the two sets of anchoring claws are opposite.

[0009] Secondly, a dispensing device is designed for dispensing the aforementioned detachment device. The dispensing device includes a dispensing cylinder with a hollow dispensing connector at the bottom end. The side wall of the dispensing connector has a hanging hole that mates with a locking block. During dispensing, the retrieval head extends into the dispensing connector. The dispensing cylinder is also equipped with a torsion rod and a motor. The torsion rod extends into the dispensing connector and mates with the torsion part. The motor drives the torsion rod to rotate axially. A dispensing rope cap is provided at the top of the dispensing cylinder.

[0010] As a preferred solution for the dispenser, the dispenser body is composed of a battery section and a dispenser section connected vertically. The battery section contains a battery assembly, which is connected to the dispenser section via a socket connector. The dispenser section contains a control circuit for controlling the start and stop of the motor.

[0011] The method for deploying the aforementioned release device using the aforementioned release device involves the following steps: First, place the release device fixing pin in the horizontal groove of the L-shaped groove, at which point the anchoring claw retracts; then, place the release device release connector onto the top of the release device release cylinder, at which point the locking block is located in the hanging hole, the retrieval rod extends into the release connector, and the torsion rod is inserted into the torsion part; lower the release device and release device connected together to the depth to be measured downhole by connecting the release rope cap with a rope, the motor drives the torsion rod to place the fixing pin in the vertical groove of the L-shaped groove, the anchoring rod moves downward under the action of the first compression spring, the anchoring claw unfolds, and the release device is anchored inside the wellbore; pull the rope to detach the release connector from the top of the release cylinder and pull it back to the surface.

[0012] Next, a retrieval device is designed for retrieving the aforementioned detachment device. It includes a retrieval cylinder with an axially movable unlocking rod inside. The unlocking rod is in contact with a third compression spring under downward force. An axially movable thrust cylinder is fitted externally, also in contact with a thrust spring under downward force. A locking steel ball is located on the side wall of the retrieval cylinder. The inner side of the locking steel ball abuts against a groove on the side wall of the unlocking rod, and the outer side abuts against a groove on the side wall of the thrust cylinder. The unlocking rod, located below the locking steel ball, has a smaller diameter, forming a receiving portion for the unlocked locking steel ball. The retrieval device also includes a relief rod. A hollow slip is located at the bottom of the retrieval cylinder. The bottom end of the relief rod extends into the slip, and its top end connects to the unlocking rod. During retrieval, the frustum-shaped retrieval head of the detachment device extends into the slip and strikes the relief rod. A retrieval rope cap is located at the top of the retrieval cylinder.

[0013] As a preferred design for the salvage device, the restoring force of the thrust spring is greater than that of the first compression spring. The collet and the fourth compression spring are pressed downwards by the force.

[0014] The method for retrieving the aforementioned detachment device using the aforementioned retrieval device involves the following steps: The retrieval device is lowered above the detachment device downhole via a rope connected to a retrieval rope cap. It impacts the detachment device with initial velocity, causing the retrieval head to extend into the slips and impact the unloading rod. The unlocking rod moves upward under force, locking the steel ball into the receiving part. The thrust cylinder unlocks and moves downward under the action of the thrust spring. This continues until the thrust cylinder acts downward on the detachment cylinder, the slips act upward on the retrieval head, causing the anchoring rod to move upward, and the anchoring claw retracts, releasing the anchor from the wellbore. Finally, the retrieval device and detachment device, connected together, are pulled back to the surface via a rope.

[0015] Finally, a downhole pressure dynamic monitoring and decoupling tool is provided, including the aforementioned decoupling device, as well as the aforementioned matching dropper and retrieval device.

[0016] In summary, compared with the prior art, the advantages and beneficial effects of this invention are as follows: the entire monitoring process only requires no more than 2 days of operation time for deployment and retrieval, which fundamentally reduces operating costs, alleviates the labor intensity of employees, improves the utilization rate of well testing equipment, and reduces safety risks such as wellhead blowout prevention system leakage and wire corrosion. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of the embodiments of the present invention and form part of this application, are not intended to limit the embodiments of the present invention.

[0018] Figure 1 The dispenser is designed to withstand pressure.

[0019] Figure 2 Flowchart of a microcontroller program.

[0020] Figure 3 The dispenser dispenses short sections.

[0021] Figure 4 Dispenser battery short section.

[0022] Figure 5 Schematic diagram of the anchoring mechanism for the decoupling device.

[0023] Figure 6 Decoupling device anchor claw.

[0024] Figure 7 Reverse anchoring claw of the decoupling device.

[0025] Figure 8 Decoupling device.

[0026] Figure 9 Salvage equipment.

[0027] Figure 10 XGQV100 software interface.

[0028] Figure 11 Dispenser section.

[0029] Figure 12 Decoupling short section.

[0030] Figure 13 Short section of the salvage device.

[0031] Figure 14 The dispenser is connected to the unattachment device.

[0032] Figure 15 Delivery process one.

[0033] Figure 16 Delivery process two.

[0034] Figure 17 The process of the dispenser detaching from the de-attachment device (Part 1).

[0035] Figure 18 Part Two: The process of the dispenser detaching from the de-attachment device.

[0036] Figure 19 The salvage process, part one.

[0037] Figure 20 The second part of the salvage process.

[0038] Figure 21 The third step in the salvage process.

[0039] The reference numerals and corresponding component names in the attached diagrams are as follows:

[0040] 100-Decoupling device; 101-Decoupling cylinder; 102-Retrieval rod; 103-L-shaped groove; 104-Fixing pin; 105-Retrieval head; 106-Torsion part; 107-Anchoring rod; 108-First compression spring; 109-Pressure gauge mounting part; 110-Anchoring claw; 111-Connecting rod; 112-Locking block; 113-Second compression spring;

[0041] 200-Dispenser; 201-Dispensing cylinder; 202-Dispensing connector; 203-Hanging hole; 204-Torsion rod; 205-Motor; 206-Dispensing rope cap; 207-Battery assembly; 208-Socket connector; 209-Control circuit.

[0042] 300-Retrieving device; 301-Retrieving cylinder body; 302-Unlocking rod; 303-Third compression spring; 304-Thrust cylinder; 305-Thrust spring; 306-Locking steel ball; 307-Receiving part; 308-Unloading rod; 309-Clamping slip; 310-Retrieving rope cap; 311-Fourth compression spring. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of the present invention clearer, the principles and features of the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the scope of protection of the present invention.

[0044] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other instances, well-known structures, circuits, materials, or methods have not been specifically described in order to avoid obscuring the invention.

[0045] Throughout this specification, references to "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the invention. Therefore, the phrases "an embodiment," "an example," "an example," or "an example" appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. Moreover, those skilled in the art will understand that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0046] The following discloses various implementation methods or embodiments of the described subject matter technical solutions. To simplify the disclosure, specific embodiments of one or more arrangements of the features are described below, but the embodiments are not intended to limit this specification. The connection between the first feature and the second feature described later in the specification can include implementations with direct connection, implementations that form additional features, and further, implementations that use one or more other intervening features to indirectly connect or combine the first feature and the second feature with each other, so that the first feature and the second feature are not directly connected.

[0047] In the description of this invention, it should be understood that the terms "front", "rear", "left", "right", "upper", "lower", "vertical", "horizontal", "top", "bottom", "high", "low", "inner", "outer", "center", "length", "circumference", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0048] In the description of this specification, "multiple" means at least two, such as two, three, etc., unless otherwise expressly and specifically limited.

[0049] The terminology used in this specification is that which is currently widely used in the art in consideration of the functionality of this disclosure; however, these terms may vary depending on the intent, precedent, or new technology of those skilled in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of this disclosure. Therefore, the terminology used in this specification should not be construed as simple names, but rather based on the meaning of the terms and the overall description of this disclosure.

[0050] This specification uses flowcharts or text to illustrate the operational steps performed according to the embodiments of this application. It should be understood that the operational steps in the embodiments of this application are not necessarily performed precisely in the order described. Instead, as needed, various steps can be processed in reverse order or simultaneously. Furthermore, other operations can be added to these processes, or one or more operations can be removed from these processes.

[0051] The purpose of this invention is to develop a pressure gauge detachment tool suitable for high-pressure sulfur-containing gas wells. Specifically, the design utilizes a wireline-operated, safe, and reliable mechanical detachment tool for the pressure gauge, allowing it to remain in the well for extended periods to collect pressure data. To achieve the above objective, this invention adopts the following specific implementation scheme:

[0052] Example 1

[0053] Regarding the design of the decoupling device:

[0054] (1) Design of the triggering mechanism

[0055] The release device is deployed using a dispenser, and is triggered by a motor after being placed at the designated location. The structure of the triggering mechanism is an important part of the design.

[0056] After the release device is triggered, it anchors inside the oil pipe, and the force ensuring reliable anchoring is provided by a spring. The locking mechanism uses a groove on the retrieval rod and a fixing pin to achieve axial displacement of the fixed frame, thus achieving limit locking. By rotating the retrieval head, the axial displacement is released through a pre-reserved opening on the retrieval rod, thereby triggering the release device.

[0057] (2) Design of anchoring mechanism

[0058] As a key component of the decoupling device, the reliability of the anchoring mechanism directly affects the instrument's operational status.

[0059] The anchoring mechanism employs a linkage structure, which is simple in design. Because it uses a low-pair structure, it can withstand larger loads, ensuring reliable anchoring. The principle of the anchoring mechanism is as follows: Figure 5 As shown.

[0060] The anchoring mechanism also includes the design of the anchoring claws; different claw tooth profiles can affect anchoring reliability. Based on design experience from other instruments, selecting a tooth profile validated by other instruments reduces working time and improves reliability. Anchoring claws, such as... Figure 6 As shown, the reverse anchoring claw is as follows Figure 7 As shown.

[0061] Since the anchoring claw is a key component of the release device and bears significant forces, its material and heat treatment process must be strictly controlled. Because other instruments in the Southwest Oil and Gas Field have used similar structures with good results, the same materials and heat treatment processes were selected to shorten the testing cycle. To improve the surface hardness of the anchoring claw, the tooth surfaces were carburized.

[0062] (3) Design results

[0063] Decoupling device Figure 8 As shown.

[0064] Based on the above design concept, this embodiment designs a detachment device 100, which includes a detachment cylinder 101. The detachment cylinder 101 is provided with an axially movable retrieval rod 102 inside. The side wall of the retrieval rod 102 is provided with an L-shaped groove 103. The detachment cylinder 101 is provided with a fixing pin 104 inside. The fixing pin 104 is located in the L-shaped groove 103. Two sets of fixing pins 104 and L-shaped grooves 103 are arranged opposite to each other. The top of the retrieval rod 102 extends out of the detachment cylinder 101 and is provided with a retrieval head 105. The retrieval head 105 is in the shape of a frustum with a smaller top and a larger bottom (the "upper" and "lower" in this invention refer to the direction from the wellhead to the bottom of the gas well). The top of the retrieval head 105 has a torsion part 106, which is hexagonal. The detachment cylinder 101 is equipped with an axially movable anchor rod 107. The top end of the anchor rod 107 is axially rotatably connected to the bottom end of the retrieval rod 102. The anchor rod 107 is in contact with the first compression spring 108 under downward force. The bottom end of the anchor rod 107 extends out of the detachment cylinder 101 and is equipped with a pressure gauge mounting part 109. The detachment device 100 also includes an anchor claw 110 and a connecting rod 111 that are hinged to each other. The anchor claw 110 is also hinged to the anchor rod 107, and the connecting rod 111 is also hinged to the detachment cylinder 101. An extension hole for the anchor claw 110 is provided on the detachment cylinder 101. The detachment device 100 also includes a locking block 112, which is hinged to the detachment cylinder 101. An extension hole for the locking block 112 is provided on the detachment cylinder 101, and the inner side of the locking block 112 is in contact with the second compression spring 113 under upward force.

[0065] In one optional embodiment, three anchoring claws 110 are evenly distributed along the circumferential direction at the same height position of the detachment cylinder 101. Two sets of anchoring claws 110 are provided along the length direction of the detachment cylinder 101, and the tooth profiles of the two sets of anchoring claws 110 are opposite.

[0066] Example 2

[0067] Regarding the design of the dispenser:

[0068] The initial purpose of developing the electronic release device was to free well testing operations from the constraints of wirelines, allowing instruments to be placed downhole, increasing wireline utilization, and reducing downhole costs. The release device must be able to be smoothly lowered to a designated location using wirelines. Upon triggering in a certain way, the outer diameter of the release device rapidly increases, locking onto the inner wall of the tubing. Then, the wireline is retrieved, leaving the release device and instruments downhole. After testing, a special tool is used to retrieve them using wirelines.

[0069] The dispenser uses an electric structure. According to the set time, the motor rotates, which drives the central rod of the decoupling device to rotate through the transmission shaft. After reaching a certain position, the spring can be released.

[0070] The triggering mechanism can be either electric or mechanical. Electric mechanisms are more complex, have lower reliability of electronic components, and are relatively more expensive. Mechanical mechanisms are compact, more reliable, and can significantly reduce costs.

[0071] After analyzing and comparing the advantages and disadvantages of the two structures, the mechanical structure was ultimately chosen. The structure used for anchoring to the inner wall of the tubing employs three anchoring claws, not anchoring the entire circumference, thus avoiding interference with the flow of fluid within the tubing. The anchoring claws utilize a linkage mechanism, relying on springs for energy storage. Once the trigger condition is met, the spring force is released, causing the anchoring claws to expand from their retracted state, completing the anchoring action.

[0072] (1) Motor selection

[0073] The motors are mainly from Shanghai Xinyi Motor and Swiss Maxon Motor. The Shanghai Xinyi motor is rated for 150℃, but based on past experience, its operation is unreliable at 150℃. To ensure instrument reliability, the more stable imported Swiss Maxon motor was selected.

[0074] (2) Battery selection

[0075] For downhole instruments, all batteries used are high-temperature resistant imported batteries. Initially, two types of motors were selected. Through comparison, the 3B1065 had a small battery capacity, insufficient driving force, and a short operating time; the ER26505, although with a slightly lower battery voltage, had a large capacity, which could increase battery life. The disadvantage was that it was larger in size, increasing the length of the instrument.

[0076] Table 1 Comparison of the dimensions and performance of the two types of batteries

[0077] Diameter (mm) 14 25.5 Length (mm) 48.5 49 Voltage (V) 3.9 3.67 Battery capacity (Ah) 1.6 5.2

[0078] Since the rated voltage of the motor is 24V, the battery pack needs to be at least 12V to ensure the output torque of the motor. Therefore, four batteries are connected in series to ensure the battery voltage.

[0079] (3) Pressure bearing and sealing design

[0080] The dispenser is electrically controlled and requires pressure-bearing and sealing design. O-rings are used for sealing, including seals at the battery connection, circuit sleeve, and drive shaft. The sealing design is standard for petroleum instruments and can be directly referenced. The instrument's design specification is a pressure resistance of 80MPa, based on the theory of metal pipes withstanding external pressure.

[0081] The steel pipe strength calculation is for downhole instruments, which can be simplified as a cylinder sealed at both ends subjected to external pressure, with the material under triaxial compressive stress.

[0082] For typical downhole instruments, the ratio of the outer diameter to the inner diameter of the tube, d2 / d1, is greater than 1.1, so the calculation formula for a thick-walled cylinder is used. The principal stresses on the cylindrical surface with radius r are considered when a cylinder subjected to external pressure p is subjected to external pressure p.

[0083] σ r ---Radial stress;

[0084] σ t --- Tangential stress;

[0085] σ z ---Radial stress;

[0086] The formula is:

[0087] σ r =-pr 22 (1-r 12 / r2) / (r 22 -r 12 )

[0088] σ r =-pr 22 (1+r 12 / r2) / (r 22 -r 12 )

[0089] σ r =-pr 22 / (r 22 -r 12 )

[0090] Based on the triaxial compressive stress state of the material, steel pipes are classified as ductile materials.

[0091] According to the third strength theory, the failure condition is: σ1 - σ3 = σ s ;

[0092] Strength condition: σ III =σ1-σ3≤[σ]=σ s / n ;

[0093] The strength theory is limited to room temperature and static load; isotropic materials; σ1, σ2, and σ3 are three mutually perpendicular principal stresses, and their algebraic values ​​are specified as σ1 > σ2 > σ3; the safety factor n = 1.2 to 2.2.

[0094] Based on this theory, we used a small software program to verify the pressure resistance of pipelines. According to the inner and outer radii of the thinnest part of the pipe wall and the materials used, we checked the pressure resistance performance of the casing. The pressure resistance design of the 200-ton delivery device is as follows: Figure 1 As shown, it meets the design requirements.

[0095] (4) Circuit Design

[0096] The instrument's communication interface uses a U-to-serial port, which is compatible with the pressure gauge direct reader and is used for debugging and parameter reading and writing settings.

[0097] The microcontroller uses internal Flash memory to store information such as instrument number, remaining battery cycles, and deployment delay time. See the microcontroller program flowchart below. Figure 2 The communication baud rate is 115200, which is compatible with pressure gauges.

[0098] (5) XGQV100 software system

[0099] The XGQV100 software is used to set the action time of the electric feeder and define the trigger time for the suspension device. It is easy to operate. The XGQV100 software interface is as follows: Figure 10 As shown.

[0100] (6) Design Results

[0101] Short sections such as Figure 3 As shown, the battery segment is as follows Figure 4 As shown.

[0102] Based on the above design concept, this embodiment designs a dispenser 200 for dispensing the detacher 100 of Embodiment 1. The dispenser 200 includes a dispensing cylinder 201, a hollow dispensing connector 202 at the bottom of the dispensing cylinder 201, and a hanging hole 203 on the side wall of the dispensing connector 202 that cooperates with the locking block 112. During dispensing, the retrieval head 105 extends into the dispensing connector 202. The dispensing cylinder 201 is also provided with a torsion rod 204 and a motor 205. The torsion rod 204 extends into the dispensing connector 202 and cooperates with the torsion part 106. The motor 205 drives the torsion rod 204 to rotate axially. A dispensing rope cap 206 is provided at the top of the dispensing cylinder 201.

[0103] In one optional embodiment, the dispensing cylinder 201 is composed of a battery section and a dispensing section connected vertically. The battery section contains a battery assembly 207, which is connected to the dispensing section via a socket connector 208. The dispensing section contains a control circuit 209 for controlling the start and stop of the motor.

[0104] (7) Delivery process

[0105] The connection between the dispenser and the unattachment device is as follows: Figure 14 As shown, the delivery process is as follows: Figure 15-16 As shown, after the instrument is lowered to the predetermined position, the motor starts to operate. The hexagon on the release device drives the hexagon inside the release device to rotate. The fixing pin rotates in the radial groove relative to the retrieval head until it rotates to the radial groove contact limit. Under the action of the spring, the retrieval head and the center rod move downward (relatively, the fixed lower body moves upward), and the anchoring claw and the reverse anchoring claw open and anchor to the inner wall of the oil pipe.

[0106] Disengagement of the dispenser and the release device Figure 17-18 As shown, after the decoupling device is anchored, the dispenser is lifted. Since the locking block has been released, the locking block can be flipped upwards, thereby disengaging the dispenser from the decoupling device.

[0107] Specifically, dispenser 200, such as Figure 11 As shown, the decoupling device 100 is as follows Figure 12 As shown. The method for deploying the detacher 100 of Embodiment 1 using the deployer 200 of this embodiment comprises the following steps: First, the fixing pin 104 of the detacher 100 is placed in the transverse groove of the L-shaped groove 103, at which time the anchoring claw 110 retracts; then, the deployment connector 202 of the deployer 200 is fitted onto the top of the detachment cylinder 101 of the detacher 100, at which time the locking block 112 is located in the hanging hole 203, the retrieval rod 102 extends into the deployment connector 202, and the torsion rod 204 is inserted into the torsion bar. The rotating part 106; the delivery cap 206 is connected by a rope to lower the delivery device 200 and the release device 100 connected together to the depth to be measured in the well. The motor 205 drives the torsion bar 204 to place the fixing pin 104 in the vertical groove of the L-shaped groove 103. The anchoring rod 107 moves downward under the action of the first compression spring 108, and the anchoring claw 110 unfolds, so that the release device 100 is anchored in the well. The rope is pulled to disengage the delivery joint 202 from the top of the release cylinder 101 and pull it back to the surface.

[0108] Example 3

[0109] Regarding the design of the salvage device:

[0110] The docking of the retrieval device with the release device downhole is quite complex. Using an electrically powered mechanism would significantly increase design difficulty and is unnecessary. Ultimately, the retrieval device adopts a purely mechanical structure, relying on the impact between the retrieval device and the release device to achieve docking and simultaneously trigger the retrieval device, causing the release device to disengage. The retrieval device uses a purely mechanical structure, based on the original tack device, with added release functionality.

[0111] (1) Design of the card unlocking function

[0112] The release mechanism is activated by the spring force pushing against the fixed frame. To release the anchor during retrieval, simply press down on the fixed frame to retract the spring. The release function of the retrieval device is designed based on this principle.

[0113] The retrieval device's unblocking function also relies on a spring. In the initial state, the spring contracts and stores energy. Once it successfully docks with the release device, it triggers the retrieval device, causing the spring on the retrieval device to release. The outer shell of the retrieval device then presses down on the fixed frame of the release device, thus achieving the unblocking function.

[0114] By calculating that the minimum spring force after the spring on the retrieval device is extended is greater than the spring force after the spring on the release device is compressed, the anchoring claw of the release device can be guaranteed to be fully retracted after release. The spring force is calculated as follows.

[0115] The basic formulas for designing and calculating cylindrical helical compression springs are:

[0116]

[0117]

[0118]

[0119]

[0120] In the formula: τ -- shear stress (MPa);

[0121] τ p --Allowable shear stress (MPa);

[0122] F -- The working load of the spring (N);

[0123] f -- Deformation under working load (mm);

[0124] k -- Spring stiffness (N / mm);

[0125] U -- Spring deformation energy (N·mm);

[0126] d -- Material diameter (mm);

[0127] D -- Spring mean diameter (mm);

[0128] C -- winding ratio, C = D / d;

[0129] K -- curvature coefficient, calculated by the following formula:

[0130]

[0131] n -- the effective number of coils of the spring;

[0132] G -- Shear modulus (MPa).

[0133] From the above formula, the formula for calculating the diameter of the material can be derived as follows:

[0134]

[0135] The formula for calculating the effective number of coils of a spring is:

[0136]

[0137] F0 -- The load on the spring in its free state when compressed, F0 = 0.

[0138] (2) Design Results

[0139] Salvage equipment such as Figure 9 As shown.

[0140] Based on the above design concept, this embodiment designs a retrieval device 300 for retrieving the detachment device 100 of the above embodiment 1. It includes a retrieval cylinder 301, an axially movable unlocking rod 302 inside the retrieval cylinder 301, the unlocking rod 302 and the third compression spring 303 are subjected to downward force and abut against each other, and an axially movable thrust cylinder 304 is sleeved on the outside, the thrust cylinder 304 and the thrust spring 305 are subjected to downward force and abut against each other, a locking steel ball 306 is provided on the side wall of the retrieval cylinder 301, the inner side of the locking steel ball 306 abuts against the groove on the side wall of the unlocking rod 302, and the outer side abuts against the groove on the side wall of the thrust cylinder 304. The unlocking rod 302 is located below the locking steel ball 306 and its diameter decreases to form a receiving part 307 after the locking steel ball is unlocked. The retrieval device 300 also includes a jacking rod 308. A hollow slip 309 is provided at the bottom of the retrieval cylinder 301. The bottom end of the jacking rod 308 extends into the slip 309, and its top end is connected to the unlocking rod 302. During retrieval, the frustum-shaped retrieval head 105 of the release device 100 extends into the slip 309 and impacts the jacking rod 308. A retrieval rope cap 310 is provided at the top of the retrieval cylinder 301.

[0141] In an optional embodiment, the restoring force of the thrust spring 305 is greater than the restoring force of the first compression spring 108. The collide 309 and the fourth compression spring 311 are subjected to downward force and abut against each other.

[0142] (3) Salvage process

[0143] like Figure 19-21 As shown, when the retrieval device descends to about 10 meters above the release device, it begins to fall freely. Under the impact, the retrieval head of the release device enters the retrieval device's slip, and after entering, it hits the unloading rod, causing the locking steel ball to release the thrust spring's limit. The thrust spring pushes the thrust cylinder downward, pressing down on the release device's fixed frame. The anchoring claw and the reverse anchoring claw flip downward and retract, allowing the retrieval device and the release device to be retrieved together smoothly.

[0144] Specifically, the decoupling device 100, such as Figure 12 As shown, the 300-type salvage device Figure 13 As shown. The method for retrieving the detachment device 100 of Embodiment 1 using the retrieval device 300 of this embodiment includes the following steps: The retrieval device 300 is lowered above the detachment device 100 in the well using a retrieval rope cap 310 connected by a rope, and impacts the detachment device 100 with initial velocity. The retrieval head 105 of the detachment device 100 extends into the slip 309 and impacts the unloading rod 308. The unlocking rod 302 moves upward under force, the locking steel ball 306 enters the receiving part 307, the thrust cylinder 304 unlocks and moves downward under the action of the thrust spring 305; until the thrust cylinder 304 acts downward on the detachment cylinder 101, the slip 309 acts upward on the retrieval head 105, causing the anchoring rod 107 to move upward, and the anchoring claw 110 retracts to release the anchor from the wellbore; the retrieval device 300 and the detachment device 100, which are connected together, are pulled back to the surface using a rope.

[0145] Example 4

[0146] This embodiment provides a downhole pressure dynamic monitoring detachment tool, including a detacher 100 as described in Embodiment 1, a dispenser 200 as described in Embodiment 2, and a retrieval tool 300 as described in Embodiment 3.

[0147] Key technical specifications of each part of the unloading tool:

[0148] Instrument outer diameter: Φ42mm;

[0149] Instrument operating length: <1500mm;

[0150] Applicable pressure range: 0~80MPa;

[0151] Applicable temperature range: -40℃~+150℃;

[0152] Instrument power consumption: <120mA (motor start), <0.1mA (sleep mode);

[0153] Battery voltage: 3.67V × 4 = 14.68V;

[0154] Battery capacity: 5.2AH;

[0155] Battery life: 256 cycles;

[0156] Programming time: 1 minute to 24 hours.

[0157] In this embodiment, the downhole pressure dynamic monitoring decoupling tool completes anchoring, deployment, and retrieval through the following steps:

[0158] 1) Use specialized software to set the electronic release time point of 100°, connect the tool string, and then use wireline operation to lower the tool string and downhole pressure gauge into the wellbore;

[0159] 2) Descend to the target layer, and when the release time arrives, the motor 205 of the release device 200 rotates, triggering the anchoring claw 110 of the release device 100 to open, so that the release device 100 is anchored on the inner wall of the oil pipe.

[0160] 3) At the same time, the dispenser 200 and the detacher 100 automatically separate, then the dispenser 200 is lifted up and pulled out of the wellbore to complete the dispensing operation. The detacher 100 carries the pressure gauge to monitor downhole.

[0161] 4) After monitoring is completed, the detachment device 100 and the downhole pressure gauge are retrieved from the well using a wireline retrieval device 300.

[0162] In summary, this invention presents an electronic decoupling device with a pressure resistance of 80MPa and a temperature resistance of 150℃. It features a large-capacity battery pack for the decoupling device, strong motor drive, and smooth deployment. The decoupling device's oil production linkage mechanism design ensures rapid action, a compact structure, bidirectional anchoring, mechanical self-locking, and high reliability. Indoor and simulation tests have proven that the materials meet design requirements, and the mechanical movement is reliable and stable. The successful development of this decoupling device can change the traditional processes of production well testing, interference well testing, and pressure recovery well testing, which involve long pressure monitoring times, require significant manpower and resources, and incur high operating costs. It improves the utilization rate of personnel and equipment, alleviates the labor intensity of on-site operators, and reduces the safety risks of oil and gas well testing and construction. It provides a set of high-tech, adaptable, and safe supporting technologies for dynamic monitoring of oil and gas fields in central Sichuan.

[0163] This tool is suitable for long-term downhole pressure dynamic monitoring in high-pressure sulfur-containing gas wells. Using this detacher for pressure monitoring directly reduces the operation time for special well tests from 10 days to 2 days, lowering the labor intensity of operators and improving equipment efficiency. It also ensures the integrity of the wellhead and reduces the safety risks of testing operations. Furthermore, it offers significant economic benefits. Calculations show that the cost of well test monitoring is 37,600 yuan per day. Currently, it has been applied in 9 wells, saving approximately 4,211,200 yuan in monitoring costs. It can reduce the downhole risks of high temperature, high pressure, and high sulfur content in high-temperature, high-grind gas wells in high-oil-density areas, solving the downhole pressure monitoring problem in key oil and gas reservoirs, and has promising application prospects.

[0164] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A decoupling device, characterized in that: The detachment device includes a detachment cylinder, inside which is a retrieval rod that can move axially relative to the detachment rod. The side wall of the retrieval rod is provided with an L-shaped groove. Inside the detachment cylinder, there is a fixing pin located in the L-shaped groove. The top of the retrieval rod extends out of the detachment cylinder and is provided with a retrieval head. The retrieval head is a frustum-shaped cone with a smaller top and a larger bottom, and the top of the retrieval head has a torsion part. The detachment cylinder is equipped with an axially movable anchor rod. The top of the anchor rod is axially rotatably connected to the bottom of the retrieval rod. The anchor rod is pressed against the first compression spring under downward force. The bottom of the anchor rod extends out of the detachment cylinder and is equipped with a pressure gauge mounting part. The release device also includes anchoring claws and connecting rods that are hinged to each other. The anchoring claws are also hinged to the anchoring rods, and the connecting rods are also hinged to the release cylinder. An anchoring claw protrusion holes are opened on the release cylinder. The anchoring claws are arranged in the circumferential direction at the same height position of the release cylinder. Two sets of anchoring claws are arranged along the length of the release cylinder, and the tooth shape of the two sets of anchoring claws is opposite. The release device also includes a locking block, which is hinged to the release cylinder. The release cylinder has a locking block extension hole, and the inner side of the locking block is in contact with the second compression spring under upward force.

2. The decoupling device according to claim 1, characterized in that: Three anchoring claws are evenly distributed along the circumference at the same height position on the detachment cylinder.

3. A downhole pressure dynamic monitoring and decoupling tool, characterized in that: The device includes the detachment device as described in any one of claims 1-2, and further includes a release device. The release device includes a release cylinder, a hollow release connector at the bottom end of the release cylinder, a hanging hole on the side wall of the release connector that cooperates with the locking block, and a retrieval head that extends into the release connector during release. The release cylinder is also provided with a torsion rod and a motor. The torsion rod extends into the release connector and cooperates with the torsion part. The motor drives the torsion rod to rotate axially. A release rope cap is provided at the top of the release cylinder.

4. The downhole pressure dynamic monitoring and uncoupling tool according to claim 3, characterized in that: The dispensing cylinder is composed of a battery section and a dispensing section connected vertically. The battery section contains a battery assembly, which is connected to the dispensing section via a socket connector. The dispensing section contains a control circuit for controlling the start and stop of the motor.

5. A method for deploying the decoupling device using the downhole pressure dynamic monitoring decoupling tool as described in any one of claims 3-4, characterized in that, The following steps are to be performed: First, place the fixing pin of the release device in the horizontal groove of the L-shaped groove, at which point the anchoring claw retracts; then, place the release connector of the release device onto the top of the release cylinder of the release device, at which point the locking block is located in the hanging hole, the retrieval rod extends into the release connector, and the torsion rod is inserted into the torsion part; lower the release device and the release device connected together to the depth to be measured downhole by connecting the release rope cap with the rope, the motor drives the torsion rod to place the fixing pin in the vertical groove of the L-shaped groove, the anchoring rod moves downward under the action of the first compression spring, the anchoring claw unfolds, and the release device is anchored in the wellbore; pull the rope to disengage the release connector from the top of the release cylinder and pull it back to the surface.

6. A downhole pressure dynamic monitoring and decoupling tool, characterized in that: The device includes the detachment device as described in any one of claims 1-2, and further includes a retrieval device. The retrieval device includes a retrieval cylinder, an axially movable unlocking rod inside the retrieval cylinder, the unlocking rod abutting downwards with a third compression spring, and an axially movable thrust cylinder sleeved on the outside, the thrust cylinder abutting downwards with a thrust spring. A locking steel ball is provided on the side wall of the retrieval cylinder, the inner side of the locking steel ball abutting against a groove on the side wall of the unlocking rod, and the outer side abutting against a groove on the side wall of the thrust cylinder. The unlocking rod is located below the locking steel ball, and its diameter decreases to form a receiving part after the locking steel ball is unlocked. The restoring force of the thrust spring is greater than the restoring force of the first compression spring. The retrieval device also includes a jacking rod. The bottom of the retrieval cylinder is equipped with a hollow slip. The bottom end of the jacking rod extends into the slip, and the top end is connected to the unlocking rod. During retrieval, the frustum-shaped retrieval head of the release device extends into the slip and impacts the jacking rod. The slip and the fourth compression spring are pressed downwards. A retrieval rope cap is installed at the top of the retrieval cylinder.

7. A method for retrieving the decoupling device using the downhole pressure dynamic monitoring decoupling tool as described in claim 6, characterized in that, The following steps are performed: Connect the retrieval rope cap via a rope, lower the retrieval device above the downhole release device, and impact the release device with initial velocity. The retrieval head of the release device extends into the slips and impacts the unloading rod. The unlocking rod moves upward under force, locking the steel ball into the receiving part. The thrust cylinder unlocks and moves downward under the action of the thrust spring. Until the thrust cylinder acts downward on the release cylinder body, the slips act upward on the retrieval head, causing the anchoring rod to move upward, and the anchoring claw retracts to release the anchoring from the wellbore. The retrieval device and release device, which are connected together, are pulled back to the surface via a rope.

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