A downhole drill string stroke monitoring and torque protection device

Abstract

The present invention discloses a downhole drill tool stroke monitoring and torque protection device, wherein the outer side of the upper joint pipe is rotatably connected to a tube shell, and an annular device installation cavity section is provided between the inner wall of the tube shell and the outer wall of the upper joint pipe; the clutch assembly is located at the top of the device installation cavity section and is used to connect the power between the upper joint pipe and the tube shell; the telescopic end of the hollow hydraulic jack is connected to the clutch assembly and is used to control the access state of the clutch assembly; the lower joint pipe can be connected to the external downhole drill tool transmission, the lower joint pipe is axially slidingly connected between the upper joint pipe and the tube shell, the tube shell and the lower joint pipe rotate synchronously, the piston cylinder of the drill tool stroke monitoring assembly is connected to the top end of the lower joint pipe and monitors the axial displacement stroke of the lower joint pipe through the component assembly, the present invention realizes high-precision real-time monitoring of the telescopic amount of the downhole drill tool through air pressure detection, can safely cut off the torque power, significantly reduces the fatigue risk of the drill tool and the drilling accident rate, and improves the safety and efficiency of complex formation operations.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas drilling engineering, and particularly relates to a downhole drilling tool stroke monitoring and torque protection device. Background Art

[0002] In oil and gas drilling, PDC drill bits commonly experience dynamic instability caused by stick-slip vibration when penetrating soft and hard formations. Existing technical solutions primarily focus on controlling the cutting depth of the PDC bit or using constant torque tools to suppress stick-slip vibration.

[0003] While controlling the cutting depth of a PDC drill bit can regulate drilling speed and efficiency to a certain extent, it focuses on intervening in the bit's cutting behavior rather than directly monitoring the expansion and contraction of the lower drill string. This approach fails to provide real-time insight into the actual expansion and contraction of the drill string during drilling. In complex and changing geological environments, drill string expansion and contraction can be extremely complex. Without accurate monitoring of this expansion and contraction, potential risks cannot be anticipated, increasing the likelihood of damage to the drill string or even drilling accidents.

[0004] The strategy of using constant torque tools to suppress stick-slip vibrations primarily focuses on regulating torque fluctuations to reduce the adverse effects of vibration on drill tools and the drilling process. However, it lacks targeted monitoring and effective control of the telescopic displacement of the lower drill tool. In actual drilling, drill tool expansion and contraction are influenced by numerous factors, such as sudden changes in formation hardness and fluctuations in drilling fluid pressure. Without real-time monitoring of drill tool expansion and contraction, exceeding safety limits can easily lead to fatigue damage to the drill tool, loosening of joints, or even fracture, seriously threatening the smooth progress of drilling operations.

[0005] Furthermore, existing technologies often exhibit limited adaptability when dealing with complex geological conditions and specialized drilling scenarios. For example, when encountering extremely hard formations or sudden structural changes, drill tool expansion and contraction changes can become more dramatic and unpredictable. However, existing technologies are unable to accurately and timely capture these rapidly changing expansion and contraction dynamics, making it impossible to quickly and effectively implement appropriate protective measures, significantly hindering the efficient and safe conduct of drilling operations.

[0006] Therefore, how to provide a downhole tool that can effectively monitor the downhole drilling tool stroke and provide torque protection is a problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0007] In view of this, the present invention provides a downhole drill tool stroke monitoring and torque protection device, which is connected between the drill tool and the rotary power source and becomes the key to ensuring drilling safety and improving the durability of the drill tool system.

[0008] In order to achieve the above-mentioned object, the present invention adopts the following technical solution: a downhole drilling tool stroke monitoring and torque protection device for transmitting and connecting a rotating power source at the top and a downhole drilling tool at the bottom, comprising:

[0009] An upper joint pipe, the upper joint pipe being drivingly connected to an external rotating power source, the outer side of the upper joint pipe being rotatably connected to a tube shell, an annular device mounting cavity section being provided between the inner wall of the tube shell and the outer wall of the upper joint pipe;

[0010] a clutch assembly, the clutch assembly being located at the top of the device mounting cavity section and being used to connect the power between the upper joint tube and the tube shell;

[0011] A hollow hydraulic jack, located in the middle of the device mounting cavity section and fixedly connected to the tube housing, the telescopic end of the hollow hydraulic jack being connected to the clutch assembly and used to control the engagement state of the clutch assembly;

[0012] A drill stroke monitoring assembly, comprising a piston cylinder, a component assembly, and an air chamber. The piston cylinder is located at the bottom of the component mounting cavity section and is fixedly connected to the tubular housing. The air chamber is connected to and communicates with one side of the piston cylinder. The component assembly is used to detect pressure and temperature data inside the air chamber. The component assembly is electrically connected to the controller of the hollow hydraulic jack.

[0013] The lower joint pipe is used for transmission connection with the external downhole drilling tool. The lower joint pipe is axially slidably connected between the upper joint pipe and the tube shell. A key connection section for transmitting torque is provided between the tube shell and the lower joint pipe. The telescopic end of the piston cylinder is connected to the top end of the lower joint pipe. The movement of the telescopic end of the piston cylinder changes the pressure and temperature state inside the gas tank.

[0014] The beneficial effects of the present invention are as follows: the upper joint pipe is used to connect to the rotating power source, and the lower joint pipe is used to connect to the downhole drill tool. When in use, the displacement of the downhole drill tool is directly monitored by the drill tool stroke monitoring component, and the displacement stroke of the downhole drill tool is timely monitored by the internal sensor, which can accurately capture the dynamic expansion and contraction changes of the drill tool under complex geological conditions, provide real-time data support for drilling operations, and effectively avoid drill tool damage and drilling accidents caused by abnormal expansion and contraction displacement. In addition, when the monitoring exceeds the normal expansion and contraction change, the expansion and contraction state of the hollow hydraulic jack can be controlled to adjust the access of the clutch assembly, thereby effectively cutting off the power transmission between the upper joint pipe and the tube shell, preventing the drill tool from being damaged by excessive torque, and realizing the torque protection function. The present invention realizes high-precision real-time monitoring of the expansion and contraction amount of the expansion and contraction end of the piston cylinder through air pressure detection of the component assembly, combined with adaptive torque protection threshold adjustment, significantly reduces the fatigue risk of the drill tool and the drilling accident rate, and improves the safety and efficiency of complex formation operations.

[0015] Preferably, an anti-drop component is fixed on the outer wall of the upper joint pipe near the top to prevent the pipe shell from moving downward, and an anti-drop component is fixed on the bottom end of the pipe shell to prevent the lower joint pipe from falling.

[0016] The resulting technical effect is: the pipe shell is connected to the outside of the upper joint pipe by fixed axis rotation, the anti-drop component can ensure that the pipe shell falls off from the upper joint pipe when the drill tool is lifted, and the anti-fall component can limit the downward movement of the lower joint pipe to prevent the lower joint pipe from falling from the pipe shell.

[0017] Preferably, the anti-drop component includes an anti-drop ring and an anti-drop ring cover, the anti-drop ring is fixedly connected to the outer wall of the upper joint tube, the anti-drop ring cover is fixed to the top of the inner wall of the tube shell, the anti-drop ring abuts the bottom of the anti-drop ring cover and prevents the anti-drop ring cover and the tube shell from moving downward; the anti-drop component includes an anti-drop ring and an anti-drop ring cover, the anti-drop ring is fixedly connected to the outer wall of the lower joint tube, the anti-drop ring cover is fixedly connected to the bottom end edge of the tube shell, the anti-drop ring cover abuts the bottom of the anti-drop ring and prevents the anti-drop ring and the lower joint tube from falling.

[0018] The resulting technical effect is: the cooperation of the anti-drop component and the anti-fall component can ensure the overall relationship between the upper joint pipe, the pipe shell and the lower joint pipe, and avoid the parts from coming off and affecting the subsequent use of the equipment. It should be noted that during the specific implementation, a sealing ring is set on the inner wall of the anti-drop ring cover to ensure the dynamic sealing connection between the anti-drop ring cover and the upper joint pipe, and a sealing ring is set on the inner wall of the anti-drop ring cover to ensure the dynamic sealing connection between the anti-drop ring cover and the lower joint pipe, so as to avoid drilling fluid from entering the interior of the device and damaging components, thereby extending the service life of the equipment.

[0019] Preferably, a thrust string bearing is installed between the inner wall of the tube shell and the outer wall of the upper joint tube, and the thrust string bearing is located below the anti-drop component.

[0020] The resulting technical effect is that the thrust string bearing realizes the rotational connection between the pipe shell and the upper joint pipe, and can also meet the use of high-thrust drilling. Based on the installation of the thrust string bearing, the anti-drop component provides safety insurance.

[0021] Preferably, the clutch assembly includes a plurality of friction ring plates and a torque engagement sleeve arranged in a stacked manner, a plurality of key grooves are provided on the circumferential sides of the plurality of friction ring plates, the torque engagement sleeve is located on the outside of some of the friction ring plates, a plurality of splines are provided on the inner and outer walls of the torque engagement sleeve corresponding to the axial direction of the torque engagement sleeve, the inner side wall of the tube shell is provided with a key groove matching the splines, the torque engagement sleeve rotates synchronously with the friction ring plate on its inner side and the tube shell on its outer side, the friction ring plate on the top layer is fixed to the outer wall of the upper joint tube, and the friction ring plate on the bottom layer is fixedly connected to the telescopic end of the hollow hydraulic jack, and the telescopic end of the hollow hydraulic jack provides axial pressure and promotes the synchronous rotation of the plurality of friction ring plates.

[0022] The resulting technical effect is that the clutch assembly is used to connect the torque transmission between the upper joint pipe and the pipe shell. It can be understood that the torque engagement sleeve is not completely sleeved on the outside of all the friction ring plates, but some friction ring plates are exposed, in order to ensure the engagement of the clutch. Only when multiple friction ring plates are compressed by axial force can the rotational torque of the upper joint pipe be transmitted to the pipe shell through the friction ring plates and the torque engagement sleeve, so that the synchronous rotation of the upper joint pipe and the pipe shell can be achieved. When the multiple friction ring plates are not axially pressed, the rotational power of the upper joint pipe is interrupted at the friction ring plates and cannot be transmitted to the torque engagement sleeve, thereby cutting off the rotation of the pipe shell and protecting the drilling tool below.

[0023] Preferably, the gas chamber is connected to and communicated with the cylinder body side of the piston cylinder, the component assembly is fixed on the gas chamber, and a thermal insulation layer is provided on the outer side of the gas chamber and the outer side of the component assembly.

[0024] The resulting technical effect is: the expansion and contraction of the piston cylinder can change the internal pressure state and temperature state of the gas chamber. The sensor calculates the expansion and contraction of the drill tool below by monitoring the pressure state and temperature state, thereby judging the working condition of the drill tool below. In order to ensure the accuracy of data monitoring, an insulation layer is arranged to reduce the impact of the external environment on the detection data. At the same time, the insulation layer also ensures the normal use environment of the components. Before specific implementation, it is necessary to correct the data on the ground and obtain the relationship curve between temperature, pressure and expansion and contraction of the piston cylinder. It should be noted that this product does not rely on an external air supply source to pump air into the piston cylinder, and the piston cylinder is not a hydraulic cylinder body. Instead, it relies on the change of the air pressure inside the existing piston cylinder to obtain the movement of the expansion and contraction end of the piston cylinder, thereby obtaining the expansion and contraction of the downhole drill tool.

[0025] Preferably, the component assembly includes a temperature sensor, a pressure sensor, a battery and a microprocessor. The temperature sensor is used to detect the temperature data in the gas chamber, and the pressure sensor is used to detect the pressure data in the gas chamber. The microprocessor electrical signal connects the temperature sensor, the pressure sensor and the controller of the hollow hydraulic jack, and the battery supplies power to the temperature sensor, the pressure sensor and the controller of the hollow hydraulic jack.

[0026] The resulting technical effect is that the microprocessor is linked to the controller of the hollow hydraulic jack. When the telescopic displacement of the drill tool exceeds the safe range, the hollow hydraulic jack can be controlled to quickly cut off the torque transmission, preventing the drill tool from being damaged by excessive torque. At the same time, through the precise control of the hydraulic jack by the controller, the torque protection threshold can be dynamically adjusted according to the actual working conditions to adapt to different geological conditions and drilling conditions. In specific implementation, the heat dissipation of the components can be achieved by the drilling fluid inside the upper joint pipe. Part of the component assembly can be close to the outer wall of the upper joint pipe, relying on the high-speed drilling fluid flowing in the pipe to remove the heat from the components. The remaining area is wrapped with a thermal insulation layer to achieve thermal insulation protection for the components. Note that the components do not need to be completely wrapped, and the side close to the outer wall of the upper joint pipe is relatively exposed to facilitate heat exchange.

[0027] Preferably, a support and limiting sleeve is fixed on the inner side of the tube shell and corresponds to the top area of the lower joint tube. The inner wall of the support and limiting sleeve is slidably connected to the outer wall of the lower joint tube. The support and limiting sleeve is used to limit the telescopic end stroke of the piston cylinder.

[0028] The resulting technical effect is that the support and limiting sleeve can, on the one hand, limit the terminal stroke of the telescopic end of the piston cylinder, and on the other hand, provide support and guidance for the movement of the lower joint pipe, making its movement more reliable.

[0029] Preferably, the support and limiting sleeve is located above the key connection section, and a key block and a strip slide groove are provided in the key connection section. The key block is connected to the axial sliding of the tube shell in the strip slide groove, and the key block is fixed on the outer wall of the lower joint tube, and the strip slide groove is provided on the inner side wall of the tube shell; or the key block is fixed on the inner wall of the tube shell, and the strip slide groove is provided on the outer wall of the lower joint tube.

[0030] The resulting technical effect is that the key connection section is provided to ensure axial mobility between the lower joint tube and the tube shell, while also enabling torque transmission from the tube shell to the lower joint tube.

[0031] Preferably, a boss is provided near the bottom end of the inner wall of the tube shell, a step is provided on the outer wall of the lower joint tube and near the top side of the anti-fall component, a wave spring is sleeved on the outer wall of the lower joint tube, the bottom end of the wave spring abuts against the step, and the top end of the wave spring abuts against the boss.

[0032] The resulting technical effect is that the wave spring can act as a buffer when the drill tool is extended and retracted, and is used to buffer the mechanical impact of the drill tool during normal extension and retraction. The wave spring has a strong vibration reduction ability, thereby ensuring the stability of the overall device. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is an overall structural diagram of a downhole drilling tool stroke monitoring and torque protection device of the present invention;

[0034] Figure 2 This is an AA cross-sectional view of a downhole drilling tool stroke monitoring and torque protection device according to the present invention;

[0035] Figure 3 This is a schematic diagram of a downhole drilling tool stroke monitoring and torque protection device of the present invention without the casing;

[0036] Figure 4 This is a schematic diagram of the piston-cylinder layout of a downhole drilling tool stroke monitoring and torque protection device of the present invention;

[0037] Figure 5 This is a structural diagram of a clutch assembly of a downhole drilling tool stroke monitoring and torque protection device of the present invention;

[0038] Figure 6 This is a schematic diagram of an anti-drop component of a downhole drilling tool stroke monitoring and torque protection device of the present invention;

[0039] Figure 7 This is a schematic diagram of an anti-fall component of a downhole drilling tool stroke monitoring and torque protection device of the present invention;

[0040] Figure 8 This is a schematic diagram of a lower joint pipe of a downhole drilling tool stroke monitoring and torque protection device of the present invention;

[0041] Figure 9 This is a schematic diagram of a pipe shell of a downhole drilling tool stroke monitoring and torque protection device of the present invention.

[0042] 1 Upper joint tube, 2 tube shell, 201 boss, 3 device installation cavity section, 4 clutch assembly, 401 friction ring plate, 4011 keyway, 402 torque coupling sleeve, 4021 spline, 5 hollow hydraulic jack, 6 drill stroke monitoring assembly, 601 piston cylinder, 602 component assembly, 603 air chamber, 7 lower joint tube, 701 step, 8 key connection section, 9 anti-drop assembly, 901 anti-drop ring, 902 anti-drop ring cover, 10 anti-drop assembly, 101 anti-drop ring, 102 anti-drop ring cover, 11 thrust string bearing, 12 support limit sleeve, 13 wave spring, 14 spring preload gasket. DETAILED DESCRIPTION

[0043] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0044] See the attached Figures 1 to 9 According to an embodiment of the present invention, a downhole drilling tool stroke monitoring and torque protection device is provided, which is used to transmit and connect a rotary power source at a top end and a downhole drilling tool at a bottom end, and includes:

[0045] The upper joint tube 1 is connected to the external rotating power source in a transmission manner. The upper joint tube is a stepped tube with a non-uniform outer diameter. The outer side of the upper joint tube 1 is rotatably connected to the tube shell 2. An annular device installation cavity section 3 is provided between the inner wall of the tube shell 2 and the outer wall of the upper joint tube 1. In specific implementation, in order to facilitate assembly, the tube shell 2 is usually installed in a multi-section structure;

[0046] The clutch assembly 4 is located at the top of the device installation cavity section 3 and is used to connect the power between the upper joint tube 1 and the tube shell 2. The power transmission between the tube shell 2 and the upper joint tube 1 depends on the working state of the clutch assembly 4;

[0047] The hollow hydraulic jack 5 is located in the middle of the device installation cavity section 3. Its cylinder is fixedly connected to the tube shell 2. The telescopic end of the hollow hydraulic jack 5 is the plunger, which is connected to the clutch assembly 4 and is used to control the engagement state of the clutch assembly 4.

[0048] The drilling tool stroke monitoring assembly 6 includes a piston cylinder 601, a component assembly 602 and an air chamber 603. The piston cylinder 601 is located at the bottom of the device installation cavity section 3 and is fixedly connected to the tube shell 2. The air chamber 603 is connected and communicated with one side of the piston cylinder. The component assembly 602 is used to detect the pressure and temperature data inside the air chamber. The component assembly 602 is electrically connected to the controller of the hollow hydraulic jack 5 through the lower joint pipe 7. The lower joint pipe 7 is connected to the lower downhole drilling tool for transmission. The lower joint pipe 7 is axially slidably connected between the upper joint pipe 1 and the tube shell 2. It should be noted that there is a sealing ring between the lower joint pipe 7 and the upper joint pipe 1. The lower joint pipe 7 and the upper joint pipe 1 are relatively slidable, that is, they can move axially and rotate circumferentially.

[0049] A key connection section 8 for transmitting torque is provided between the tube shell 2 and the lower joint tube 7 to ensure that the torque of the tube shell is smoothly transmitted to the lower joint tube and the downhole drilling tool. The telescopic end of the piston cylinder 601 is connected to the top of the lower joint tube 7. The component assembly 602 can detect the pressure state in the air chamber 603, thereby monitoring the axial displacement stroke of the lower joint tube 7. When it exceeds the safety range, the hollow hydraulic jack 5 can be used to control the access state of the clutch assembly 4, thereby cutting off the torque transmission between the upper joint tube 1 and the tube shell 2, thereby protecting the use of the downhole drilling tool.

[0050] In other embodiments, an anti-drop component 9 is fixed on the outer wall of the upper joint tube 1 near the top to prevent the tube shell 2 from moving downward, and an anti-drop component 10 is fixed on the bottom end of the tube shell 2 to prevent the lower joint tube 7 from falling.

[0051] Specifically, the anti-drop assembly 9 includes an anti-drop ring 901 and an anti-drop ring cover 902. The anti-drop ring 901 is threadedly fixedly connected to the outer wall of the upper joint pipe 1, and the anti-drop ring cover 902 is threadedly fixed to the top of the inner wall of the tube shell 2. The anti-drop ring 901 abuts the bottom of the anti-drop ring cover 902 and prevents the anti-drop ring cover 902 and the tube shell 2 from moving downward. In specific implementation, in order to improve the sealing performance, an annular groove is provided on the inner wall of the anti-drop ring cover 902, and an O-ring is installed in the annular groove, thereby achieving a seal between the anti-drop ring cover 902 and the outer wall of the upper joint pipe 1.

[0052] The anti-fall component 10 includes an anti-fall ring 101 and an anti-fall ring cover 102. The anti-fall ring 101 is threadedly connected to the outer wall of the lower joint pipe 7, and the anti-fall ring cover 102 is threadedly connected to the bottom edge of the tube shell 2. The anti-fall ring cover 102 abuts the bottom of the anti-fall ring 101 and prevents the anti-fall ring 101 and the lower joint pipe 7 from falling. Similarly, in order to improve the sealing of the system, an O-ring is arranged between the anti-fall ring cover 102 and the outer wall of the lower joint pipe 7 to form a double sealing ring anti-well fluid intrusion structure. After installing the O-ring, it can effectively prevent well fluid from entering the interior of the device, protect internal components from corrosion and damage, and further improve the reliability and durability of the device.

[0053] It should be noted that abutment is not a fixed connection relationship, and circumferential rotation can occur between the relative components.

[0054] In other specific embodiments, a thrust string bearing 11 is installed between the inner wall of the pipe shell 2 and the outer wall of the upper joint pipe 1. The thrust string bearing 11 is located below the anti-drop component 9. The thrust string bearing is the basis for the rotation between the pipe shell 2 and the upper joint pipe 1. This component can also ensure the downward pressure of the device and ensure the downward exploration of the downhole drilling tool.

[0055] In some other embodiments, the clutch assembly 4 includes a plurality of friction ring plates 401 and a torque engagement sleeve 402 arranged in a stacked manner. A plurality of key slots 4011 are provided on the circumference of each of the friction ring plates 401. The torque engagement sleeve 402 is located outside some of the friction ring plates 401. It should be noted that when the torque engagement sleeve is located outside all of the friction ring plates, the clutch loses its torque-cutting function.

[0056] A plurality of splines 4021 are respectively provided on the inner and outer walls of the torque coupling sleeve 402 corresponding to the axial direction of the torque coupling sleeve, and a keyway matching the spline 4021 is provided on the inner side wall of the tube shell 2. The torque coupling sleeve 402 rotates synchronously with the friction ring plate 401 inside it and the tube shell 2 outside. The friction ring plate 401 on the top layer is fixed on the outer wall of the upper joint tube 1, and the friction ring plate 401 on the bottom layer is fixedly connected to the telescopic end of the hollow hydraulic jack 5. The telescopic end of the hollow hydraulic jack is the plunger of the jack. The telescopic end of the hollow hydraulic jack 5 provides axial pressure and causes the multiple friction ring plates 401 to rotate synchronously. When the hollow hydraulic jack 5 does not provide axial pressure, the multiple friction ring plates are loosely abutted against each other, and the friction force between adjacent friction ring plates cannot effectively transmit torque, so the torque transmission is interrupted.

[0057] In some other specific embodiments, the cylinder body side close to the piston cylinder 601 is connected and communicated with an air tank 603. The piston cylinder is not a conventional air cylinder. It has a sealing cylinder part and a piston rod part. There is gas in the sealing cylinder part, which is connected to the air tank 603. The movement of the piston rod part will link the change of the pressure and temperature conditions in the sealing cylinder part and the air tank, so as to know the movement amount of the telescopic end of the piston cylinder. The component assembly 602 is fixed on the air tank 603 and is used to detect the pressure and temperature data inside the air tank. The component assembly 602 is electrically connected to the controller of the hollow hydraulic jack 5. The outside of the air tank 603 and the outside of the component assembly 602 are provided with a thermal insulation layer to ensure that all electronic components in the component assembly 602 can operate at high temperature. For example, laying porous vacuum silicon with a thickness of 4 mm or thicker can ensure the normal operation of the internal components of the device at 150°C.

[0058] It should be noted that before use, the sensors in the component assembly need to be calibrated and the corresponding relationship between pressure, temperature and the numerical changes of the telescopic end of the piston cylinder needs to be obtained.

[0059] The component assembly 602 includes a temperature sensor, a pressure sensor, a battery and a microprocessor. The temperature sensor is used to detect the temperature data in the gas chamber 603. The pressure sensor is used to detect the pressure data in the gas chamber 603. The microprocessor electrical signal is connected to the temperature sensor, the pressure sensor and the controller of the hollow hydraulic jack. The battery supplies power to the temperature sensor, the pressure sensor and the controller of the hollow hydraulic jack. The microprocessor can be connected to an external electronic control system to implement the setting of predetermined programs and online operations.

[0060] The component assembly 602 is partially close to the outer wall of the upper joint pipe 1, which facilitates heat exchange between the high-speed flowing drilling fluid inside and the component assembly 602, effectively cooling and protecting the components. This cooperates with the insulation layer to achieve the protection of the component assembly 602.

[0061] The air pressure sensor detects the air chamber pressure fluctuations caused by the extension and retraction of the drill tool in real time. The microprocessor determines whether to trigger the retraction action of the hydraulic jack's plunger based on the preset safety threshold. The microprocessor is connected to an external electronic control system. The staff can dynamically adjust the torque protection threshold through the electronic control system and adaptively correct the safety range according to the formation hardness and drilling fluid pressure parameters.

[0062] The calculation method of the present invention for monitoring the expansion and contraction dynamics of the drilling tool by detecting the air pressure in the air chamber is as follows:

[0063] When the drilling tool is extended or retracted, the piston (i.e., the retractable end of the piston cylinder) moves, causing the volume of gas in the gas chamber 603 to change. The specific relationship is:

[0064] ΔV=AΔx

[0065] Where A is the effective cross-sectional area of the piston, unit is m 2 ; Δx is the drilling tool telescopic displacement, unit is m; ΔV is the volume change of gas in the gas chamber 603, unit is m 3 .

[0066] Assuming that the gas in the gas chamber is an ideal gas and the temperature is constant (isothermal process), when the drilling tool displacement is Δx, the volume change of the gas in the gas chamber is ΔV = AΔx. According to the ideal gas state equation:

[0067] p0V0=p(V0+AΔx)

[0068] Where p0 is the initial pressure in the gas chamber, in Pa; V0 is the initial volume of gas in the gas chamber, in m 3 ; ΔV is the change in gas volume in the gas chamber.

[0069] The relationship between the air pressure change (Δp) and the drilling tool telescopic displacement (Δx) is derived as follows:

[0070]

[0071] If the underground temperature changes significantly, the temperature sensor data T should also be introduced for correction:

[0072]

[0073] Where T0 is the initial temperature of the temperature sensor, unit is K, and T is the real-time temperature collected by the temperature sensor, unit is K.

[0074] Therefore, the calculation formula for the drilling tool expansion displacement after adding temperature correction is:

[0075]

[0076] In practical applications, data deviations may occur due to piston-cylinder friction, gas chamber leakage, or nonlinear deformation. Experimental calibration can also be used:

[0077] Δx=aΔp+b(Δp) 2 +C

[0078] The formula uses a combination of static calibration and dynamic compensation. The air pressure is measured under known displacement, the fitting coefficients a, b, and C are then adjusted based on the temperature data. Where a0 is the initial calibration coefficient.

[0079] The safety displacement threshold set in actual use is x max , the torque protection function is executed when the following conditions are met:

[0080]

[0081] In some other embodiments, a support and limiting sleeve 12 is fixed to the inner side of the tube shell 2 and corresponds to the top area of the lower joint tube 7. The inner wall of the support and limiting sleeve 12 is slidably connected to the outer wall of the lower joint tube 7. The support and limiting sleeve 12 is used to limit the telescopic end stroke of the piston cylinder 601. The support and limiting sleeve 12 also provides support and guidance for the movement of the lower joint tube.

[0082] In some other specific embodiments, the support and limiting sleeve 12 is located above the key connection section 8, and a key block and a strip slide groove are provided in the key connection section 8. The key block is connected to the strip slide groove in an axial sliding manner corresponding to the tube shell 2. The key block is fixed on the outer wall of the lower joint tube 7, and the strip slide groove is opened on the inner side wall of the tube shell 2; or the key block is fixed on the inner wall of the tube shell 2, and the strip slide groove is opened on the outer wall of the lower joint tube 7, so as to ensure the torque transmission between the tube shell and the lower joint tube.

[0083] In some other embodiments, a boss 201 is provided near the bottom end of the inner wall of the tube shell 2, a step 701 is provided on the outer wall of the lower joint tube 7 and near the top side of the anti-fall component 10, and a wave spring 13 is sleeved on the outer wall of the lower joint tube 7. The bottom end of the wave spring 13 abuts against the step 701, and the top end of the wave spring 13 abuts against the boss 201. The wave spring can buffer the expansion and contraction of the downhole drilling tool. In specific implementation, a pre-tightening gasket 14 can also be added to the end of the wave spring 13, and the pre-tightening gasket 14 can abut against the step 701 or the boss 201.

[0084] The principle and working process of the present invention are as follows:

[0085] Initial state:

[0086] At the start of drilling operations, the system is initially stationary. The hollow hydraulic jack plunger is in the extended position, providing upward thrust to the system. The friction rings in the clutch assembly are now pressed against each other. Torque is transmitted to the casing via the torque coupling sleeve, driving the lower joint pipe and tool rotation. The telescopic end of the piston cylinder in the drill tool stroke monitoring assembly is in a floating position, allowing the drill tool to perform normal telescopic movement.

[0087] During the torque transmission process between components, the upper joint pipe 1 transmits the torque to the torque coupling sleeve 402 through the friction ring 401 of the clutch assembly 4. The torque coupling sleeve 402 rotates synchronously with the pipe shell 2. The key connection section 8 between the pipe shell 2 and the lower joint pipe 7 causes the lower joint pipe 7 to rotate, thereby driving the downhole drilling tool to rotate.

[0088] Torque cut-off is the cutting off of power transmission at the clutch assembly 4;

[0089] Displacement relationship of components under the extension and contraction state of the drill tool:

[0090] The expansion and contraction of the downhole drilling tool will directly cause the lower joint pipe 7 to undergo axial displacement, and the lower joint pipe 7 will move upward relative to the upper joint pipe 1 and the pipe shell 2. Based on the axial relative displacement between the lower joint pipe 7 and the pipe shell 2, the wave spring 13 is compressed at this time to buffer the mechanical impact. When the lower joint pipe 7 moves upward, the expansion end of the piston cylinder is directly retracted, and the pressure in the air chamber changes. The sensor detects the pressure value, thereby determining the specific displacement of the lower joint pipe 7 and the downhole drilling tool. During this process, the pipe shell 2 and the upper joint pipe 1 do not undergo relative axial displacement.

[0091] Normal drilling operation:

[0092] When the lower drill string penetrates complex formations, it periodically expands and contracts due to interlaced soft and hard formations and variations in the drill bit's cutting depth. The telescopic end of the piston cylinder senses the drill string's expansion and contraction in real time. This movement causes pressure fluctuations within the piston cylinder and the gas chamber. The pressure and temperature sensors in the component assembly collect real-time pressure and temperature data within the gas chamber and provide feedback to the embedded microprocessor.

[0093] Implementation of the torque protection mechanism:

[0094] When abnormal telescopic displacement of the drill tool is detected, the hollow hydraulic jack receives instructions from the microprocessor to quickly retract the plunger, so that the friction ring is in a loosened abutment state. At this time, the torque coupling sleeve no longer transmits power, thereby stopping the transmission of torque to the drill tool.

[0095] Reset preparation and continue drilling:

[0096] When the drill tool's telescopic displacement returns to a safe range, the microprocessor re-controls the hollow hydraulic jack to eject the plunger, re-tightening the multi-layer friction rings and resuming torque transmission. The system then enters normal operating mode, with the sensor assembly continuously monitoring the drill tool's telescopic movement.

[0097] The thermal insulation design of this invention can extend the service life of components. The thermal insulation material on the outer layer of the component assembly can effectively isolate the impact of the high temperature environment underground from the sensors and controllers, ensuring the accuracy of monitoring data and the long-term stability of the equipment, while reducing equipment maintenance costs and replacement frequency.

[0098] The present invention features a compact structure and strong adaptability. Its modular design, with components connected by threads and splines, ensures overall structural stability and reliability. Furthermore, the device can accommodate drilling tools of varying sizes and complex drilling environments, demonstrating its wide applicability.

[0099] The present invention realizes real-time monitoring of the expansion and contraction amount of the drilling tool through air pressure detection, and cuts off torque transmission through a clutch component when the displacement exceeds the limit, thereby protecting the drilling tool from fatigue damage.

[0100] As for the devices and methods of use disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the methods.

[0101] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A downhole drilling tool stroke monitoring and torque protection device, used for transmitting and connecting a rotary power source at the top and a downhole drilling tool at the bottom, characterized in that: include: An upper joint pipe (1), the upper joint pipe (1) is connected to an external rotating power source in a transmission manner, the outer side of the upper joint pipe (1) is rotatably connected to a tube shell (2), and an annular device installation cavity section (3) is provided between the inner wall of the tube shell (2) and the outer wall of the upper joint pipe (1); A clutch assembly (4), the clutch assembly (4) being located at the top of the device installation cavity section (3) and being used to connect the power between the upper joint tube (1) and the tube shell (2); a hollow hydraulic jack (5), the hollow hydraulic jack (5) being located in the middle of the device installation cavity section (3) and fixedly connected to the tube shell (2), the telescopic end of the hollow hydraulic jack (5) being connected to the clutch assembly (4) and being used to control the engagement state of the clutch assembly (4); A drilling tool stroke monitoring assembly (6), the drilling tool stroke monitoring assembly (6) comprising a piston cylinder (601), a component assembly (602) and an air chamber (603), the piston cylinder (601) being located at the bottom of the device installation cavity section (3) and fixedly connected to the tube shell (2), the air chamber (603) being connected to and in communication with one side of the piston cylinder, the component assembly (602) being used to detect pressure and temperature data inside the air chamber, and the component assembly (602) being electrically connected to a controller of the hollow hydraulic jack (5); A lower joint pipe (7) is used for transmission connection with an external downhole drilling tool. The lower joint pipe (7) is axially slidably connected between the upper joint pipe (1) and the tube shell (2). A key connection section (8) for transmitting torque is provided between the tube shell (2) and the lower joint pipe (7). The telescopic end of the piston cylinder (601) is connected to the top end of the lower joint pipe (7). The movement of the telescopic end of the piston cylinder (601) changes the pressure and temperature state inside the gas chamber (603).

2. A downhole drilling tool stroke monitoring and torque protection device according to claim 1, characterized in that: An anti-drop component (9) is fixed on the outer wall of the upper joint tube (1) near the top end to prevent the tube shell (2) from moving downward, and an anti-drop component (10) is fixed on the bottom end of the tube shell (2) to prevent the lower joint tube (7) from falling.

3. A downhole drilling tool travel monitoring and torque protection device according to claim 2, characterized in that: The anti-drop assembly (9) comprises an anti-drop ring (901) and an anti-drop ring cover (902), wherein the anti-drop ring (901) is fixedly connected to the outer wall of the upper joint tube (1), and the anti-drop ring cover (902) is fixed to the top of the inner wall of the tube shell (2), and the anti-drop ring (901) abuts against the bottom of the anti-drop ring cover (902) and prevents the anti-drop ring cover (902) and the tube shell (2) from moving downward; the anti-drop assembly (10) comprises an anti-drop ring (101) and an anti-drop ring cover (102), wherein the anti-drop ring (101) is fixedly connected to the outer wall of the lower joint tube (7), and the anti-drop ring cover (102) is fixedly connected to the bottom edge of the tube shell (2), and the anti-drop ring cover (102) abuts against the bottom of the anti-drop ring (101) and prevents the anti-drop ring (101) and the lower joint tube (7) from falling.

4. A downhole drilling tool stroke monitoring and torque protection device according to claim 2, characterized in that: A thrust string bearing (11) is installed between the inner wall of the tube shell (2) and the outer wall of the upper joint tube (1), and the thrust string bearing (11) is located below the anti-drop assembly (9).

5. The downhole drilling tool stroke monitoring and torque protection device according to claim 1, characterized in that: The clutch assembly (4) comprises a plurality of friction ring plates (401) and a torque engagement sleeve (402) arranged in a stacked manner. The circumferential sides of the plurality of friction ring plates (401) are provided with a plurality of key grooves (4011). The torque engagement sleeve (402) is located outside a portion of the friction ring plates (401). A plurality of splines (4021) are provided on the inner and outer walls of the torque engagement sleeve (402) corresponding to the axial direction of the torque engagement sleeve. The inner side wall of the tube shell (2) is provided with a plurality of key grooves (4011). The torque coupling sleeve (402) is matched with the keyway of the spline (4021), and the friction ring plate (401) inside it and the outer tube shell (2) rotate synchronously. The friction ring plate (401) on the top layer is fixed on the outer wall of the upper joint tube (1), and the friction ring plate (401) on the bottom layer is fixedly connected to the telescopic end of the hollow hydraulic jack (5). The telescopic end of the hollow hydraulic jack (5) provides axial pressure and promotes the synchronous rotation of the multiple friction ring plates (401).

6. The downhole drilling tool stroke monitoring and torque protection device according to claim 1, characterized in that: The gas chamber (603) is connected to and communicates with the cylinder body side of the piston cylinder (601), the component assembly (602) is fixed on the gas chamber (603), and a thermal insulation layer is provided on the outer side of the gas chamber (603) and the outer side of the component assembly (602).

7. A downhole drilling tool travel monitoring and torque protection device according to claim 6, characterized in that: The component assembly (602) includes a temperature sensor, a pressure sensor, a battery and a microprocessor. The temperature sensor is used to detect temperature data in the gas chamber (603), and the pressure sensor is used to detect pressure data in the gas chamber (603). The microprocessor is connected to the temperature sensor, the pressure sensor and the controller of the hollow hydraulic jack through electrical signals. The battery supplies power to the temperature sensor, the pressure sensor and the controller of the hollow hydraulic jack.

8. The downhole drilling tool stroke monitoring and torque protection device according to claim 6, characterized in that: A support and limiting sleeve (12) is fixed on the inner side of the tube shell (2) and in the top area corresponding to the lower joint tube (7). The inner wall of the support and limiting sleeve (12) is slidably connected to the outer wall of the lower joint tube (7). The support and limiting sleeve (12) is used to limit the telescopic end stroke of the piston cylinder (601).

9. The downhole drilling tool stroke monitoring and torque protection device according to claim 8, characterized in that: The supporting and limiting sleeve (12) is located above the key connection section (8), and a key block and a strip slide groove are provided in the key connection section (8). The key block is connected to the strip slide groove in an axial sliding manner corresponding to the tube shell (2). The key block is fixed on the outer wall of the lower joint tube (7), and the strip slide groove is provided on the inner wall of the tube shell (2); or the key block is fixed on the inner wall of the tube shell (2), and the strip slide groove is provided on the outer wall of the lower joint tube (7).

10. The downhole drilling tool stroke monitoring and torque protection device according to claim 1, characterized in that: A boss (201) is provided near the bottom end of the inner wall of the tube shell (2), a step (701) is provided on the outer wall of the lower joint tube (7) and near the top side of the anti-fall component (10), a wave spring (13) is sleeved on the outer wall of the lower joint tube (7), the bottom end of the wave spring (13) abuts against the step (701), and the top end of the wave spring (13) abuts against the boss (201).

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