A method and system for controlling parameters of a drill collar sub

Abstract

The application discloses a kind of drill casing joint parameter control method and system, it is related to the technical field of drill casing joint parameter control, comprising the following steps, step 1, carry out the operation of screwing and unthreading, step 2, detect whether the casing box occurs silk, if yes, then the first parameter is regulated, if no, then the first parameter is bound with finished product model.This application can significantly improve the scientificity and accuracy of drill casing joint parameter setting by deeply integrating finite element simulation pre-optimization, temperature compensation torque monitoring and machine vision online detection, building a closed-loop control system, effectively inhibiting the generation of casing box silk defect, reducing the cost of field trial and error, improving the consistency and repeatability of screwing and unthreading operation, providing strong guarantee for the safety and reliability of casing connection in oil drilling and production operation.

Description

Technical Field

[0001] This invention relates to the technical field of drill casing joint parameter control, and in particular to a method and system for controlling drill casing joint parameters. Background Technology

[0002] In oil and gas drilling and production operations, drill casing, as a core component of the wellbore structure, undertakes critical functions such as supporting the wellbore, isolating the formation, and transporting drilling fluid. The drill casing joint, as a key component connecting different sections of casing, directly determines the sealing performance and structural integrity of the entire wellbore. In actual operations, the drill casing joint and the casing thread require repeated tightening and loosening operations. Factors such as torque control, thread parameter matching, and material performance compatibility during these operations directly affect whether the casing thread will become threaded. Once the casing thread becomes threaded, it not only leads to sealing failure but may also cause serious accidents such as casing string breakage, resulting in huge economic losses and safety risks.

[0003] Currently, the control of drill casing joint parameters mainly relies on empirical formulas and on-site trial and error. Specifically, technicians initially set parameters such as the joint thread profile, bearing surface angle, female thread hardness, and coating thickness based on recommended values ​​in API standards or historical operational experience, and then verify the rationality of these parameters through on-site unloading tests. This approach has significant drawbacks: First, the parameter settings lack quantitative mechanical basis. Existing methods fail to establish a clear mapping relationship between joint parameters and stress distribution during the tightening and loosening process, resulting in a large degree of blindness in parameter selection. It is impossible to assess the stress state of the sleeve female thread under a specific parameter combination in advance, making it difficult to fundamentally avoid the risk of threading.

[0004] Second, the interference of temperature factors on torque monitoring is not effectively compensated. During the unloading operation, the torque sensor experiences thermal drift due to the temperature rise of the motor rotor, causing the measured torque value to deviate from the true value, thus resulting in a deviation between the actual applied torque and the set value. Existing technologies typically use fixed thresholds or simple linear corrections, failing to provide fine-grained compensation based on the segmented characteristics of temperature deviation, resulting in insufficient torque control accuracy.

[0005] Third, there is a lack of a closed-loop linkage mechanism between fraying detection and parameter control. In existing technologies, fraying detection mostly relies on manual visual inspection, which is inefficient and highly subjective. Even when machine vision is used, it is mostly offline inspection, and the inspection results cannot be fed back to the parameter control system in real time, making it impossible to achieve closed-loop iterative optimization, resulting in long parameter optimization cycles and high costs.

[0006] While existing technologies have conducted preliminary studies on the strength of threaded connections through finite element analysis or conducted simple monitoring of equipment status through temperature sensors, they have not yet been able to integrate finite element simulation-driven parameter pre-optimization, temperature-compensated precise torque monitoring, and machine vision-based online threading detection to form a complete, closed-loop iterative method for controlling drill sleeve joint parameters. Summary of the Invention

[0007] The purpose of this application is to provide a method and system for controlling drill casing joint parameters. By pre-optimizing the initial combination of joint parameters and female thread parameters through finite element simulation, a torque sensor with temperature compensation function is used to achieve accurate torque monitoring during the tightening and loosening operation. The screwing status of the female thread is detected online based on machine vision, and the detection results are fed back to the parameter control module for closed-loop iterative optimization. Thus, the overall drill casing joint parameters are automated, quantitative, and closed-loop controlled, effectively avoiding screwing of the female thread and improving the reliability and consistency of tightening and loosening operations.

[0008] In a first aspect, this application provides a method for controlling the parameters of a drill casing joint, comprising the following steps: Step 1: Perform unscrewing operations on the finished product according to the first parameters, which include the sleeve connector parameters and the sleeve female thread parameters. The parameters for the unscrewing operation include torque and number of cycles; Obtain the finished product model, obtain the parameters of the historical tightening and loosening operations corresponding to the finished product model, set the torque and number of cycles, and monitor the torque based on a torque sensor with temperature compensation function; Step 2: Check if the threaded part of the bushing is fraying; If so, adjust the first parameter and repeat steps 1 to 2 until the sleeve female thread no longer gets tangled. Then bind the adjusted first parameter to the finished product model. If not, then bind the first parameter to the finished product model; Each cycle of steps 1-2 yields a new finished product.

[0009] Optionally, the sleeve fitting parameters include the fitting thread profile and the bearing surface angle of the fitting thread profile; The parameters of the sleeve female thread include the sleeve female thread hardness and the sleeve female thread coating thickness; The first parameter is set based on finite element simulation; Based on the parameters of the unscrewing operation corresponding to the finished product model and the structural parameters of the finished product, finite element simulation is performed on the finished product to obtain the stress distribution of the finished product under the parameters of the unscrewing operation. When the stress distribution meets the preset conditions, the finished product structural parameters are output. When the stress distribution does not meet the preset conditions, the finished product structural parameters are adjusted until the stress distribution meets the preset conditions, at which point the finished product structural parameters are output.

[0010] Optionally, the finished product structural parameters include sleeve connector parameters, sleeve female thread parameters, and sleeve body parameters; The casing body parameters include the three-dimensional shape of the casing body and the casing body material; When the stress distribution does not meet the preset conditions, adjust the parameters of the casing joint and the casing female thread, while keeping the casing body parameters unchanged. The preset condition is defined as follows: the maximum value of the stress is less than or equal to the first value, and the stress concentration area is distributed outside the three-dimensional area of ​​the sleeve female thread.

[0011] Optionally, methods for adjusting the parameters of the casing joint and the casing thread include: Set the adjustment priority of the bushing connector parameters to the first priority and the adjustment priority of the bushing female thread parameters to the second priority. Adjust the sleeve joint parameters until the stress distribution meets the preset conditions, then stop adjusting the sleeve joint parameters and output the adjusted sleeve joint parameters. If the stress distribution does not meet the preset conditions after iterating through all sets of casing joint parameters, then the casing joint parameters and casing female thread parameters are adjusted simultaneously until the stress distribution meets the preset conditions. Then the adjustment of the casing female thread parameters is stopped, and the adjusted casing joint parameters and adjusted casing female thread parameters are output.

[0012] Optionally, methods for adjusting the parameters of the casing joint and the casing thread also include: The range of the bearing surface angle of the connector thread profile is 10° to 30°, the range of the hardness of the sleeve female thread is HRC25 to HRC35, the range of the coating thickness of the sleeve female thread is 50μm to 200μm, and the connector thread profile is trapezoidal thread or off-trapezoidal thread. Set the adjustment priority of the bearing surface angle of the connector thread profile to the first sub-level of the first priority, and set the adjustment priority of the connector thread profile to the second sub-level of the first priority; The control priority of the coating thickness of the casing female thread is set to the first sub-level of the second priority, and the control priority of the hardness of the casing female thread is set to the second sub-level of the second priority.

[0013] Optionally, the methods for setting the parameters of the unscrewing operation include: Obtain the finished product model, match the parameters of the historical tightening and loosening operations for that finished product model, calculate the average value of the parameters of the historical tightening and loosening operations for that finished product model, and use the average value as the parameter for the tightening and loosening operation.

[0014] Optionally, the torque sensor with temperature compensation function is configured at the rotor of the torque generating motor to detect the rotor temperature and rotor torque. The torque sensor with temperature compensation function is configured with a calculation method, the calculation method including: Obtain the rotor torque and rotor temperature, generate a compensation factor based on the temperature, and calculate the product of torque and compensation factor, where the product is the torque. The compensation factor is distributed between 0 and 1.

[0015] Optionally, in step 2, machine vision is used to detect whether the sleeve thread has become tangled.

[0016] Optionally, methods for detecting whether threading has occurred on the sleeve female thread include: An industrial camera is used to capture an image of the female sleeve buckle. Based on the percentage of pixels occupied by the female sleeve buckle in the image, the shooting distance and focal length of the industrial camera are adjusted so that the percentage of pixels occupied by the female sleeve buckle reaches 95% of the total pixels in the image, and the final image is output. Obtain a standard fraying image, extract the first feature value of the standard fraying image, and extract the second feature value of the final image. Calculate the similarity between the first and second feature values ​​based on cosine similarity. Based on the comparison between similarity and a preset threshold, it is determined whether the sleeve female thread has become filamentous; If the similarity is less than or equal to the preset threshold, the sleeve female thread has not been frayed; otherwise, the sleeve female thread has been frayed. Each new finished product obtained must meet the first condition, which is that the new finished product has the same model number as the original finished product and the production time is similar, where "similar" means that the interval between the production times is less than or equal to 15 days.

[0017] Secondly, a drill casing joint parameter control system includes a detection module and a control module; The detection module performs a screw-on / unscrew operation based on the finished product according to the first parameter, which includes the sleeve connector parameter and the sleeve female thread parameter. The parameters for the unscrewing operation include torque and number of cycles; Obtain the finished product model, obtain the parameters of the historical tightening and loosening operations corresponding to the finished product model, set the torque and number of cycles, and monitor the torque based on a torque sensor with temperature compensation function; The control module detects whether the sleeve thread has become unraveled; If so, adjust the first parameter and repeat steps 1 to 2 until the sleeve female thread no longer gets tangled. Then bind the adjusted first parameter to the finished product model. If not, then bind the first parameter to the finished product model; Each cycle of steps 1-2 yields a new finished product.

[0018] Compared with existing technologies, the drill casing joint parameter control method and system provided in this application deeply integrates finite element simulation pre-optimization, temperature-compensated torque monitoring and machine vision online detection to construct a closed-loop control system. This can significantly improve the scientificity and accuracy of drill casing joint parameter setting, effectively suppress the generation of casing female thread defects, reduce on-site trial and error costs, and improve the consistency and repeatability of tightening and loosening operations, thus providing a strong guarantee for the safety and reliability of casing connections in oil drilling and production operations. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a basic flowchart illustrating a method for controlling drill casing joint parameters according to an embodiment of the present invention. Detailed Implementation

[0021] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly set on the other component; when a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to the other component.

[0023] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", 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 application 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 limitations on this application.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "a plurality of" or "several" means two or more, unless otherwise explicitly specified.

[0025] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce.

[0026] Example, refer to Figure 1 As an embodiment of the present invention, a method for controlling the parameters of a drill casing joint is provided, comprising the following steps: Step 1: Perform unscrewing operations on the finished product according to the first parameters, which include the sleeve connector parameters and the sleeve female thread parameters. The parameters for the unscrewing operation include torque and number of cycles; Obtain the finished product model, obtain the parameters of the historical tightening and loosening operations corresponding to the finished product model, set the torque and number of cycles, and monitor the torque based on a torque sensor with temperature compensation function; Step 2: Check if the threaded part of the bushing is fraying; If so, adjust the first parameter and repeat steps 1 to 2 until the sleeve female thread no longer gets tangled. Then bind the adjusted first parameter to the finished product model. If not, then bind the first parameter to the finished product model; Each cycle of steps 1-2 yields a new finished product.

[0027] This invention integrates finite element simulation pre-optimization, temperature-compensated torque monitoring, and machine vision online detection to construct a closed-loop control system. This system can significantly improve the scientificity and accuracy of drill casing joint parameter settings, effectively suppress the occurrence of casing thread defects, reduce on-site trial and error costs, and improve the consistency and repeatability of tightening and loosening operations. It provides a strong guarantee for the safety and reliability of casing connections in oil drilling and production operations.

[0028] The parameters of the sleeve fitting include the thread profile and the bearing surface angle of the thread profile. The parameters of the sleeve female thread include the sleeve female thread hardness and the sleeve female thread coating thickness; The first parameter is set based on finite element simulation; Based on the parameters of the unscrewing operation corresponding to the finished product model and the structural parameters of the finished product, finite element simulation is performed on the finished product to obtain the stress distribution of the finished product under the parameters of the unscrewing operation. When the stress distribution meets the preset conditions, the finished product structural parameters are output. When the stress distribution does not meet the preset conditions, the finished product structural parameters are adjusted until the stress distribution meets the preset conditions, at which point the finished product structural parameters are output.

[0029] Specifically, finite element simulation includes the following steps: Step a1: Based on the three-dimensional shape of the casing body, the thread profile of the connector, the bearing surface angle of the thread profile of the connector, and the coating thickness of the casing female thread corresponding to the finished product model, establish the three-dimensional geometric model of the finished product. Step a2: Based on the casing material, set the elastic modulus, Poisson's ratio, and yield strength of the casing body; based on the hardness of the casing female thread, set the elastic modulus, Poisson's ratio, and yield strength of the casing female thread; based on the bearing surface angle of the joint thread profile, set the friction coefficient of the thread contact surface. Step a3: Perform finite element mesh generation on the three-dimensional geometric model. The thread engagement area, which is defined by the joint thread profile, the bearing surface angle of the joint thread profile, and the coating thickness of the sleeve female thread, adopts a fine mesh with a mesh size less than or equal to one-tenth of the height of the joint thread. The sleeve body area, which is defined by the three-dimensional shape and material of the sleeve body, adopts a conventional mesh. Step a4: Apply axial constraint to the end face of the casing body and apply rotational constraint to the end face of the casing female thread; apply rotational torque corresponding to the torque in the parameters of the tightening and loosening operation to the torque generation end, and apply axial force corresponding to the number of cycles to the end of the casing female thread; Step a5: Run the finite element solver to calculate the stress distribution of the finished product under the parameters of the unscrewing operation, and output the stress cloud diagram and stress numerical matrix. Step a6: Determine whether the stress distribution meets the following two conditions: Condition 1 is that the maximum stress value in the stress numerical matrix is ​​less than or equal to the quotient of the yield strength of the sleeve female thread and the safety factor, with the safety factor ranging from 1.2 to 2.0. Condition 2 is that the position coordinates of the stress concentration area in the stress cloud diagram are all located outside the three-dimensional area of ​​the sleeve nut in the three-dimensional geometric model; Step a7: If both conditions one and two are met, output the current finished product structure parameters as the first parameter. If either condition one or condition two is not met, the finished product structure parameters are adjusted, and the process returns to step a1. Steps a1 to a6 are executed again until both conditions one and two are met. Then, the current finished product structure parameters are output as the first parameter.

[0030] The finished product structural parameters include the sleeve connector parameters, the sleeve female thread parameters, and the sleeve body parameters; The casing body parameters include the three-dimensional shape of the casing body and the casing body material; When the stress distribution does not meet the preset conditions, adjust the parameters of the casing joint and the casing female thread, while keeping the casing body parameters unchanged. The preset condition is defined as follows: the maximum value of the stress is less than or equal to the first value, and the stress concentration area is distributed outside the three-dimensional area of ​​the sleeve female thread.

[0031] Specifically, the first value is the quotient of the yield strength of the sleeve female thread and the safety factor, with the safety factor ranging from 1.2 to 2.0; The preset conditions are derived from the basic principles of the allowable stress design method, the expression of which is: ; in, The first value is... The yield strength of the bushing thread. This is for the safety factor.

[0032] It should be noted that in the field of oil pipe materials, the safety factor for finite element analysis of casing joints is usually taken as 1.2 to 2.0.

[0033] It should be noted that the core idea of ​​distributing stress concentration areas outside the three-dimensional area of ​​the bushing thread can be summarized as controlling the risk of failure in replaceable components. The sealing criterion of the API 5C5 standard requires that the maximum stress on the sealing contact surface does not exceed the material's yield strength divided by the safety factor, and that the stress distribution is reasonable. According to the principles of engineering failure control, once the female thread of the bushing is damaged, the replacement cost is much higher than that of the joint. Therefore, the design should ensure that stress concentration occurs primarily on the joint, and that the female thread area maintains elastic deformation to avoid plastic deformation and threading. In the finite element analysis of bushing joints, stress concentration is generally observed to occur at the farthest thread root of the free end of the external thread. This is precisely the design embodiment of controlling stress concentration in the joint area and protecting the female thread.

[0034] In one embodiment, the material of the bushing female thread is P110 steel grade, the yield strength of the bushing female thread material is 825.6MPa, and the safety factor is 1.5, so the first value is 550.4MPa.

[0035] After finite element simulation, the calculated maximum stress is 600 MPa, so the parameters need to be adjusted.

[0036] In one embodiment, after obtaining the stress cloud map through finite element simulation, stress concentration areas are identified, such as areas with stress exceeding 400 MPa. If all these high-stress areas are located in the sleeve joint area, while there is no stress concentration in the sleeve female thread area.

[0037] Methods for adjusting the parameters of the casing joint and the casing thread include: Set the adjustment priority of the bushing connector parameters to the first priority and the adjustment priority of the bushing female thread parameters to the second priority. Adjust the sleeve joint parameters until the stress distribution meets the preset conditions, then stop adjusting the sleeve joint parameters and output the adjusted sleeve joint parameters. If the stress distribution does not meet the preset conditions after iterating through all sets of casing joint parameters, then the casing joint parameters and casing female thread parameters are adjusted simultaneously until the stress distribution meets the preset conditions. Then the adjustment of the casing female thread parameters is stopped, and the adjusted casing joint parameters and adjusted casing female thread parameters are output.

[0038] Specifically, based on the range of values ​​for the bearing surface angle of the connector thread profile and the selectable types of connector thread profiles, all combinations of sleeve connector parameters are generated; Following the principle that the adjustment priority of the bearing surface angle of the connector thread profile is higher than the adjustment priority of the connector thread profile, the parameters of each set of sleeve connectors are selected in sequence, and finite element simulation is performed.

[0039] Specifically, the parameters of the casing joint and the casing thread are adjusted simultaneously, including: Keeping the currently traversed bushing joint parameters unchanged, generate all combinations of bushing female thread parameters based on the range of values ​​for bushing female thread coating thickness and bushing female thread hardness. Following the principle that the control priority of the sleeve female thread coating thickness is higher than the control priority of the sleeve female thread hardness, each set of sleeve female thread parameters is selected in sequence and combined with the current sleeve joint parameters for finite element simulation. If the stress distribution still does not meet the preset conditions after iterating through the combination of each set of casing female thread parameters and the current casing joint parameters, then return to the step of adjusting the casing joint parameters, select the next set of casing joint parameters, and re-execute the step of simultaneously adjusting the casing joint parameters and casing female thread parameters until the stress distribution meets the preset conditions or all combinations have been traversed. If all combinations have been traversed and the stress distribution still does not meet the preset conditions, a control failure signal will be output, and a prompt will be made to expand the value range of the bushing joint parameters or the bushing female thread parameters.

[0040] Methods for adjusting the parameters of the casing joint and the casing thread also include: The range of the bearing surface angle of the connector thread profile is 10° to 30°, the range of the hardness of the sleeve female thread is HRC25 to HRC35, the range of the coating thickness of the sleeve female thread is 50μm to 200μm, and the connector thread profile is trapezoidal thread or off-trapezoidal thread. Set the adjustment priority of the bearing surface angle of the connector thread profile to the first sub-level of the first priority, and set the adjustment priority of the connector thread profile to the second sub-level of the first priority; The control priority of the coating thickness of the casing female thread is set to the first sub-level of the second priority, and the control priority of the hardness of the casing female thread is set to the second sub-level of the second priority.

[0041] Furthermore, based on the range of 10° to 30° for the bearing surface angle of the connector thread profile (in 1° increments) and the selectable type of connector thread profile (trapezoidal thread or off-trapezoidal thread), all combinations of sleeve connector parameters are generated, totaling 42 parameter combinations. Following the order that the adjustment priority of the bearing surface angle of the connector thread profile is higher than the adjustment priority of the connector thread profile, the parameters of each set of sleeve connectors are selected in sequence. First, the connector thread profile is fixed as a trapezoidal thread, and the bearing surface angle of the connector thread profile is gradually increased from 10° to 30° in increments of 1°. 21 sets of finite element simulations are performed in sequence. Then, the connector thread profile is fixed as a deviated trapezoidal thread, and the bearing surface angle of the connector thread profile is gradually increased from 10° to 30° in increments of 1°. 21 sets of finite element simulations are performed in sequence. After each finite element simulation, it is determined whether the stress distribution meets the preset conditions. If the stress distribution corresponding to a certain set of sleeve joint parameters meets the preset conditions, the adjustment of the sleeve joint parameters is stopped, and the current joint thread profile bearing surface angle value and the current joint thread profile are output as the adjusted sleeve joint parameters. If the above 42 sets of sleeve joint parameters are traversed and the stress distribution does not meet the preset conditions, the step of simultaneously adjusting the sleeve joint parameters and the sleeve female thread parameters is entered.

[0042] Keeping the parameters of the currently traversed bushing joints unchanged, that is, keeping the bearing surface angle value of the current joint thread profile and the current joint thread profile unchanged, and generating all combinations of bushing female thread parameters based on the range of bushing female thread coating thickness from 50μm to 200μm (step size of 10μm) and the range of bushing female thread hardness from HRC25 to HRC35 (step size of 1HRC), a total of 176 sets of parameter combinations are generated; Following the principle that the control priority of the casing female thread coating thickness is higher than that of the casing female thread hardness, the parameters of each set of casing female threads are selected in sequence. First, the casing female thread hardness is fixed at HRC25, and the casing female thread coating thickness is gradually increased from 50μm to 200μm in increments of 10μm. Sixteen sets of finite element simulations are performed in sequence. Then, the casing female thread hardness is increased by 1HRC to HRC26, and the casing female thread coating thickness is again gradually increased from 50μm to 200μm in increments of 10μm. Sixteen sets of finite element simulations are performed in sequence, and so on, until the casing female thread hardness reaches HRC35, completing all 176 sets of finite element simulations. After each finite element simulation, it is determined whether the stress distribution meets the preset conditions. If the stress distribution corresponding to a combination of a certain set of sleeve thread parameters and the current sleeve joint parameters meets the preset conditions, the adjustment of the sleeve thread parameters is stopped, and the current joint thread profile bearing surface angle value, the current joint thread profile, the current sleeve thread coating thickness value, and the current sleeve thread hardness value are output as the first parameter after adjustment. If the above 176 combinations of sleeve thread parameters and the current sleeve joint parameters are traversed and the stress distribution does not meet the preset conditions, the step of adjusting the sleeve joint parameters is returned, the next set of sleeve joint parameters is selected (according to the order set in the first priority, the joint thread profile bearing surface angle is increased by 1° or the joint thread profile is switched), and the step of simultaneously adjusting the sleeve joint parameters and sleeve thread parameters is re-executed. Repeat the above process until the stress distribution meets the preset conditions or all 42 sets of sleeve joint parameters and 176 sets of sleeve female thread parameters (a total of 7392 combinations) have been traversed. If all 7392 combinations have been traversed and the stress distribution still does not meet the preset conditions, an adjustment failure signal will be output, and a prompt will be made to expand the value range of the bearing surface angle of the joint thread profile in the sleeve joint parameters (currently 10° to 30°) or expand the value range of the coating thickness of the sleeve female thread in the sleeve female thread parameters (currently 50μm to 200μm) or the value range of the hardness of the sleeve female thread (currently HRC25 to HRC35).

[0043] The methods for setting parameters for unscrewing operations include: Obtain the finished product model, match the parameters of the historical tightening and loosening operations for that finished product model, calculate the average value of the parameters of the historical tightening and loosening operations for that finished product model, and use the average value as the parameter for the tightening and loosening operation.

[0044] The torque sensor with temperature compensation function is configured at the rotor of the torque generating motor to detect the rotor temperature and rotor torque. The torque sensor with temperature compensation function is configured with a calculation method, the calculation method including: Obtain the rotor torque and rotor temperature, generate a compensation factor based on the temperature, and calculate the product of torque and compensation factor, where the product is the torque. The compensation factor is distributed between 0 and 1.

[0045] Specifically, the calculation methods include: Step b1: Obtain the reference temperature T0 and reference torque value M0 of the rotor under rated operating conditions. The reference temperature T0 is the stable temperature when the rotor reaches thermal equilibrium during continuous operation, and the reference torque value M0 is the torque value measured by the calibrated standard torque sensor at the reference temperature T0. Step b2: Obtain the real-time temperature T of the rotor through a temperature detection unit configured at the rotor, and obtain the real-time torque measurement value Mraw of the rotor through a strain gauge torque detection unit. Step b3, calculate the temperature deviation ΔT between the real-time temperature T and the reference temperature T0, ΔT=T-T0; Step b4: Based on the sign and absolute value of the temperature deviation ΔT, generate a segmented compensation factor k. If the sign of ΔT is negative, then k=1, meaning the rotor temperature does not exceed the reference temperature, and no positive compensation is performed. If the sign of ΔT is positive, and the absolute value of ΔT is less than or equal to ΔT1, then k=1-α·ΔT, where α is the first temperature sensitivity coefficient and ΔT1 is the first temperature deviation threshold. If the sign of ΔT is positive, and the absolute value of ΔT is distributed in [ΔT1, ΔT2], then k=k1-β·(ΔT-ΔT1), where k1=1-α·ΔT1, β is the second temperature sensitivity coefficient, and ΔT2 is the second temperature deviation threshold. If the sign of ΔT is positive, and the absolute value of ΔT is greater than ΔT2, then output a temperature over-limit alarm signal and terminate the current unscrewing operation. The first temperature sensitivity coefficient α ranges from 0.001 / ℃ to 0.005 / ℃, and the second temperature sensitivity coefficient β ranges from 0.003 / ℃ to 0.008 / ℃, with β being greater than α; The first temperature deviation threshold ΔT1 ranges from 20℃ to 40℃, and the second temperature deviation threshold ΔT2 ranges from 60℃ to 80℃. Step b5: Calculate the product of the real-time torque measurement value Mrab and the compensation factor k. The product is the compensated torque Mcomp, Mcomp = Mrab·k. Step b6: Output the compensated torque Mcomp as the torque monitoring value in the parameters of the unscrewing operation; Step b7: After completing a preset number of unscrewing operation cycles, repeat step b1 to update the reference temperature T0 and reference torque value M0. The preset number of values ​​ranges from 50 to 200.

[0046] Furthermore, the automatic generation of compensation factors is achieved through PLC code, specifically including: Step c1: In the analog input module of the PLC, configure the first input channel to receive the rotor real-time temperature analog signal T output by the temperature detection unit, and configure the second input channel to receive the rotor real-time torque measurement analog signal Mraw output by the strain gauge torque detection unit. The sampling period for both the first and second input channels is set to ts, with ts ranging from 10ms to 100ms. Step c2: In the PLC's data register area, allocate a first data register to store the reference temperature T0, allocate a second data register to store the reference torque value M0, allocate a third data register to store the first temperature sensitivity coefficient α, allocate a fourth data register to store the second temperature sensitivity coefficient β, allocate a fifth data register to store the first temperature deviation threshold ΔT1, and allocate a sixth data register to store the second temperature deviation threshold ΔT2. The reference temperature T0 and the reference torque value M0 are written by an external calibration command when the PLC is first powered on, or are automatically updated by internal logic when the PLC reaches thermal equilibrium after continuous operation. Step c3: Using the PLC's arithmetic operation instructions, read the real-time temperature T of the first input channel and the reference temperature T0 of the first data register, perform a subtraction operation, the expression for the subtraction operation is ΔT=T-T0, and store the result in the seventh data register. Step c4: Using the PLC's comparison and conditional jump instructions, the value range of ΔT in the seventh data register is determined sequentially. If ΔT≤0, the compensation factor k=1 is written to the eighth data register; if 0<ΔT≤ΔT1, the first multiplication instruction is called to calculate α·ΔT, and the first subtraction instruction is called to calculate k=1-α·ΔT, and the result is written to the eighth data register; if ΔT1<ΔT≤ΔT2, the second multiplication instruction is called to calculate β·(ΔT-ΔT1), and the third subtraction instruction is called to calculate k=k1-β·(ΔT-ΔT1), where k1=1-α·ΔT1 is pre-stored in the ninth data register, and the result is written to the eighth data register; if ΔT>ΔT2, the temperature over-limit alarm flag is set, and a control signal to terminate the unscrewing operation is sent to the external actuator through the PLC's digital output module. Step c5: Using the second multiplication instruction of the PLC, read the real-time torque measurement value Mraw from the second input channel and the compensation factor k from the eighth data register, perform the multiplication operation, and the expression for the multiplication operation is Mcomp = Mraw·k. Store the compensated torque Mcomp in the tenth data register. Step c6: Through the analog output module or communication module of the PLC, the compensated torque Mcomp in the tenth data register is output to the torque display unit or torque closed-loop control unit as the torque monitoring value in the parameters of the unscrewing operation. Step c7: The number of completed unscrewing operations is accumulated using the PLC's counter instruction. When the count reaches the preset number, the interrupt service routine is updated. The interrupt service routine performs the following operations: Read the real-time temperature under the current thermal equilibrium state as the new reference temperature T0 and write it into the first data register. Read the torque value calibrated by the external standard torque sensor as the new reference torque value M0 and write it into the second data register. Clear the counter and return to the main program. The preset quantity ranges from 50 to 200.

[0047] In step 2, machine vision is used to detect whether the sleeve thread has become tangled.

[0048] Methods for detecting whether thread breakage has occurred in the bushing female thread include: An industrial camera is used to capture an image of the female sleeve buckle. Based on the percentage of pixels occupied by the female sleeve buckle in the image, the shooting distance and focal length of the industrial camera are adjusted so that the percentage of pixels occupied by the female sleeve buckle reaches 95% of the total pixels in the image, and the final image is output. Obtain a standard fraying image, extract the first feature value of the standard fraying image, and extract the second feature value of the final image. Calculate the similarity between the first and second feature values ​​based on cosine similarity. Based on the comparison between similarity and a preset threshold, it is determined whether the sleeve female thread has become filamentous; If the similarity is less than or equal to the preset threshold, the sleeve female thread has not been frayed; otherwise, the sleeve female thread has been frayed. Each new finished product obtained must meet the first condition, which is that the new finished product has the same model number as the original finished product and the production time is similar, where "similar" means that the interval between the production times is less than or equal to 15 days.

[0049] Specifically, the standard fraying image is obtained in the following way: Under laboratory conditions, using samples of the same model, material, and process as the sleeve female thread to be tested, different degrees of thread defects are artificially created through controlled unscrewing experiments. The same model and parameters of industrial camera as the on-site test are used for shooting, ensuring that the sleeve female thread occupies 95% of the total pixels of the image during shooting, consistent with the on-site test conditions. The degree of stringiness in the pre-made samples is calibrated. For example, slight stringiness: string length less than or equal to 2 mm, number of stringiness less than or equal to 3; moderate stringiness: string length 2~5 mm, number of stringiness 4~6; severe stringiness: string length greater than 5 mm, number of stringiness greater than 6. The standard fraying image contains sample images of moderate fraying as a benchmark for determining when fraying has occurred.

[0050] The standards for capturing images of the sleeve thread include: 1) Use a ring-shaped LED light source or a coaxial light source to eliminate shadow interference; 2) Use an automatic focusing system to ensure that the sleeve female clasp occupies 95% of the total pixels of the image; 3) The image resolution is greater than or equal to 1920×1080; 4) Use a solid color background, such as black or white, to facilitate feature extraction.

[0051] Specifically, the preset threshold is 0.65, and the selection methods include: Step d1: Collect N1 images confirmed to have fraying, recorded as positive samples; collect N2 images confirmed not to have fraying, recorded as negative samples; ensure that positive samples cover slight fraying, moderate fraying, and severe fraying. Step d2: Compare each verification image with the standard frayed image, calculate the cosine similarity, and draw a histogram of the similarity distribution of positive and negative samples. Step d3: Determine the optimal threshold using the ROC curve method or the F1 score maximization method. For example, when recall ≥ 90% and precision ≥ 85%, find the optimal threshold that meets the conditions through a traversal method. Step d4: Write the determined optimal threshold into the system configuration file. In actual operation, this threshold is used as the preset threshold.

[0052] In one embodiment, the API 5CT P110 7-5 / 8 drill casing connector, a pre-fabricated product used in oilfields, was used as the subject to verify and apply the parameter control method for the drill casing connector. First, based on the API 5CT P1107-5 / 8 pre-fabricated product model, historical tightening and loosening operation records for this model were retrieved from the system database. This model had undergone 326 tightening and loosening operations in the past year, with historical tightening and loosening torque data ranging from 28,000 N·m to 34,000 N·m and cycle counts ranging from 8 to 15. The calculated average historical tightening and loosening torque was 31,000 N·m, and the average number of historical cycles was 11. 31,000 N·m was used as the torque setting value for this tightening and loosening operation, and 11 cycles were used as the cycle count setting value.

[0053] Before the unscrewing operation is performed, the first parameter is preset based on finite element simulation. Specifically, the initial parameter settings for the sleeve joint are as follows: the joint thread profile is a trapezoidal thread, and the bearing surface angle of the joint thread profile is 15°; the initial parameter settings for the sleeve female thread are as follows: the sleeve female thread hardness is HRC28, and the sleeve female thread coating thickness is 80μm.

[0054] The finite element simulation process is as follows: Step a1: Based on the three-dimensional shape of the casing body (outer diameter 193.7mm, wall thickness 12.7mm, length 12m), the thread profile (trapezoidal thread), the bearing surface angle of the thread profile 15°, and the coating thickness of the casing female thread 80μm corresponding to the finished product model API 5CT P110 7-5 / 8, a three-dimensional geometric model of the finished product is established in ANSYS Workbench. The thread engagement area is modeled parametrically, with a thread profile height of 1.575mm, a pitch of 5.08mm, and a thread engagement length of approximately 76.2mm.

[0055] Step a2: Set the material parameters. The casing body material is P110 steel grade, with an elastic modulus of 210 GPa, Poisson's ratio of 0.3, and a yield strength of 758 MPa. The casing female thread has a hardness of HRC28, corresponding to an elastic modulus of 206 GPa, a Poisson's ratio of 0.29, and a yield strength of 825.6 MPa. Based on the 15° angle of the bearing surface of the thread profile, the friction coefficient of the thread contact surface is set to 0.12.

[0056] Step a3: Perform finite element mesh generation on the three-dimensional geometric model. The thread engagement area uses a fine mesh with a mesh size of 0.15 mm (less than one-tenth of the thread tooth height of 1.575 mm) and a hexahedral element type. The sleeve body area uses a conventional mesh with a mesh size of 5 mm and a tetrahedral element type. The total number of elements is approximately 2.85 million and the number of nodes is approximately 4.12 million.

[0057] Step a4: Apply boundary conditions. Apply axial constraints (Ux=Uy=Uz=0) to the end face of the casing body and rotational constraints (Rx=Ry=Rz=0) to the end face of the casing female thread. Apply a rotational torque of 31000 N·m to the torque generation end and apply an axial force to the end of the casing female thread. This axial force is determined based on the preload-cycle number relationship curve corresponding to 11 cycles and is set to 1850 kN.

[0058] Step a5: Run the finite element solver (ANSYS Mechanical APDL) to calculate the stress distribution of the finished product under the unscrewing operation parameters, and output the stress cloud diagram and stress numerical matrix.

[0059] Step a6: Determine whether the stress distribution meets the preset conditions. Condition 1: The maximum stress value in the stress numerical matrix should be less than or equal to the quotient of the yield strength of the bushing thread and the safety factor. The safety factor is 1.5, and the first value is 550.4 MPa.

[0060] Condition 2: The coordinates of the stress concentration areas in the stress cloud diagram are all located outside the three-dimensional area of ​​the bushing thread in the three-dimensional geometric model.

[0061] The finite element simulation results show that the maximum stress value is 587.3 MPa, which is greater than the first value of 550.4 MPa. Therefore, condition one is not met. The stress concentration area is mainly distributed at the farthest thread root of the external thread at the free end of the joint, and does not enter the sleeve female thread area. Therefore, condition two is met. Since condition one is not met, the finished product structural parameters need to be adjusted.

[0062] According to the control priority, the parameters of the sleeve joint are controlled first. The value range of the bearing surface angle of the joint thread profile is 10° to 30° (in increments of 1°). The joint thread profile can be either trapezoidal thread or off-trapezoidal thread, with a total of 42 combinations. Keeping the off-trapezoidal thread unchanged, the bearing surface angle is gradually increased from 15°.

[0063] When the bearing surface angle increases to 18°, the finite element simulation is re-executed (steps a1 to a6). The simulation results show that the maximum stress value is 542.1 MPa, which is less than 550.4 MPa, so condition one is met; the stress concentration area is still located in the joint area, so condition two is met. At this time, the adjustment of the sleeve joint parameters is stopped, and the adjusted sleeve joint parameters are output, including that the joint thread profile is a trapezoidal thread and the bearing surface angle of the joint thread profile is 18°.

[0064] The adjusted first parameter (joint thread profile: trapezoidal thread, joint thread profile bearing surface angle: 18°; sleeve female thread hardness: HRC28, sleeve female thread coating thickness: 80μm) is pre-bound with the finished product model API 5CT P110 7-5 / 8.

[0065] Torque during unscrewing operations is monitored using a torque sensor with temperature compensation. The torque sensor, model HBM T40B, is located on the rotor of the torque-generating motor, with a measuring range of 50,000 N·m and an accuracy class of 0.05. The temperature compensation calculation process is as follows: Step b1: When the rotor reaches thermal equilibrium (30 minutes of continuous operation with temperature fluctuation less than ±1℃ / 5 minutes), the stable temperature T0 = 42.5℃. The reference torque value M0 = 31000 N·m measured by the calibrated standard torque sensor at T0.

[0066] Step b2: The real-time rotor temperature T=58.3℃ is obtained through the PT100 temperature detection unit, and the real-time torque measurement value Mraw=32560N·m is obtained through the strain gauge torque detection unit.

[0067] Step b3, calculate the temperature deviation ΔT = 15.8℃.

[0068] Step b4: Set the first temperature sensitivity coefficient α = 0.002 / ℃, the second temperature sensitivity coefficient β = 0.005 / ℃, the first temperature deviation threshold ΔT1 = 30℃, and the second temperature deviation threshold ΔT2 = 70℃.

[0069] The compensation factor k = 1 - α·ΔT = 0.9684.

[0070] Step b5, calculate the compensated torque Mcomp = 31530.7 N·m.

[0071] Step b6: The compensated torque of 31530.7 N·m is output to the torque closed-loop control unit and compared with the set value of 31000 N·m. The control deviation is 530.7 N·m. Within the allowable deviation range (±1000 N·m), the unscrewing operation continues.

[0072] The unscrewing operation is repeated 11 times. After each cycle, the torque sensor automatically records the compensated torque value. After 11 cycles, the cumulative number of cycles reaches 11, meeting the preset cycle count requirement.

[0073] After the unscrewing operation is completed, the sleeve nut is transferred from the unscrewing station to the machine vision inspection station. The inspection system is configured as follows: the industrial camera is a Basler acA2500-14gm with a resolution of 2592×2048 pixels and a lens focal length of 35mm; the light source is a ring LED light source with a color temperature of 5600K and a power of 24W; the background is a black light-absorbing cloth.

[0074] Images of the female bushing thread are captured using an industrial camera. Initially, the female bushing thread occupies 78% of the pixels in the image. The autofocus system adjusts the camera's shooting distance (from the initial 350mm to 280mm) and focal length so that the female bushing thread occupies 95% of the total image pixels. The final image output has a resolution of 2592×2048 pixels, and the effective area of ​​the female bushing thread is approximately 2462×1946 pixels.

[0075] Obtaining standard fraying images: These standard fraying images were obtained through laboratory pre-made samples. Samples of the same model (API 5CT P110 7-5 / 8), material, and process as the female thread to be tested were used. A moderate fraying defect (fraying length 3.2mm, number of fraying points) was artificially created through a controlled unscrewing experiment. The images were taken using an industrial camera of the same model, and the shooting conditions were the same as on-site (the female thread occupies 95% of the image, ring LED light source, black background).

[0076] The first feature value of the standard frayed image is extracted using a pre-trained ResNet-50 convolutional neural network to extract deep features, outputting a 2048-dimensional feature vector, denoted as the first feature value F_std. The second feature value of the final image is then extracted using the same ResNet-50 network, outputting a 2048-dimensional feature vector, denoted as the second feature value F_test.

[0077] The similarity between the first and second features was calculated based on cosine similarity, and the similarity was found to be 0.38.

[0078] Since 0.38 is less than 0.65, it is determined that the thread of the bushing nut has not been broken.

[0079] Since no thread breakage occurred in the female bushing thread, the current first parameter (joint thread profile: trapezoidal thread, joint thread profile bearing surface angle: 18°; female bushing thread hardness: HRC28, female bushing thread coating thickness: 80μm) was formally bound to the finished product model API5CT P110 7-5 / 8 and stored in the system database as the standard parameter configuration for this model.

[0080] This invention integrates finite element simulation pre-optimization, temperature-compensated torque monitoring, and machine vision online detection to construct a closed-loop control system. This system can significantly improve the scientificity and accuracy of drill casing joint parameter settings, effectively suppress the occurrence of casing thread defects, reduce on-site trial and error costs, and improve the consistency and repeatability of tightening and loosening operations. It provides a strong guarantee for the safety and reliability of casing connections in oil drilling and production operations.

[0081] It should be understood that the use of terms such as "system," "device," "unit," and / or "module" in this application is merely one method of distinguishing different components, elements, parts, sections, or assemblies at different levels. However, if other terms can achieve the same purpose, they may be replaced by other expressions.

[0082] Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for controlling the parameters of a drill casing joint, characterized in that, Includes the following steps: Step 1: Perform unscrewing operations on the finished product according to the first parameters, which include the sleeve connector parameters and the sleeve female thread parameters. The parameters for the unscrewing operation include torque and number of cycles; Obtain the finished product model, obtain the parameters of the historical tightening and loosening operations corresponding to the finished product model, set the torque and number of cycles, and monitor the torque based on a torque sensor with temperature compensation function; Step 2: Check if the threaded part of the bushing is fraying; If so, adjust the first parameter and repeat steps 1 to 2 until the sleeve female thread no longer gets tangled. Then bind the adjusted first parameter to the finished product model. If not, then bind the first parameter to the finished product model; Each cycle of steps 1-2 yields a new finished product.

2. The method for controlling drill casing joint parameters as described in claim 1, characterized in that, The parameters of the sleeve fitting include the thread profile and the bearing surface angle of the thread profile. The parameters of the bushing thread include the hardness of the bushing thread and the coating thickness of the bushing thread. The first parameter is set based on finite element simulation; Based on the parameters of the unscrewing operation corresponding to the finished product model and the structural parameters of the finished product, finite element simulation is performed on the finished product to obtain the stress distribution of the finished product under the parameters of the unscrewing operation. When the stress distribution meets the preset conditions, the finished product structural parameters are output. When the stress distribution does not meet the preset conditions, the finished product structural parameters are adjusted until the stress distribution meets the preset conditions, at which point the finished product structural parameters are output.

3. The method for controlling drill casing joint parameters as described in claim 2, characterized in that, The finished product structural parameters include the sleeve connector parameters, the sleeve female thread parameters, and the sleeve body parameters; The casing body parameters include the three-dimensional shape of the casing body and the casing body material; When the stress distribution does not meet the preset conditions, adjust the parameters of the casing joint and the casing female thread, while keeping the casing body parameters unchanged. The preset condition is defined as follows: the maximum value of the stress is less than or equal to the first value, and the stress concentration area is distributed outside the three-dimensional area of ​​the sleeve female thread.

4. The method for controlling drill casing joint parameters as described in claim 2, characterized in that, Methods for adjusting the parameters of the casing joint and the casing thread include: Set the adjustment priority of the bushing connector parameters to the first priority and the adjustment priority of the bushing female thread parameters to the second priority. Adjust the sleeve joint parameters until the stress distribution meets the preset conditions, then stop adjusting the sleeve joint parameters and output the adjusted sleeve joint parameters. If the stress distribution does not meet the preset conditions after iterating through all sets of casing joint parameters, then the casing joint parameters and casing female thread parameters are adjusted simultaneously until the stress distribution meets the preset conditions. Then the adjustment of the casing female thread parameters is stopped, and the adjusted casing joint parameters and adjusted casing female thread parameters are output.

5. The method for controlling drill casing joint parameters as described in claim 3, characterized in that, Methods for adjusting the parameters of the casing joint and the casing thread also include: The range of the bearing surface angle of the connector thread profile is 10° to 30°, the range of the hardness of the sleeve female thread is HRC25 to HRC35, the range of the coating thickness of the sleeve female thread is 50μm to 200μm, and the connector thread profile is trapezoidal thread or off-trapezoidal thread. Set the adjustment priority of the bearing surface angle of the connector thread profile to the first sub-level of the first priority, and set the adjustment priority of the connector thread profile to the second sub-level of the first priority; The control priority of the casing female thread coating thickness is set to the first sub-level of the second priority, and the control priority of the casing female thread hardness is set to the second sub-level of the second priority.

6. The method for controlling drill casing joint parameters as described in claim 1, characterized in that, The methods for setting parameters for the unscrewing and loosening operations include: Obtain the finished product model, match the parameters of the historical tightening and loosening operations for that finished product model, calculate the average value of the parameters of the historical tightening and loosening operations for that finished product model, and use the average value as the parameter for the tightening and loosening operation.

7. The method for controlling drill casing joint parameters as described in claim 1, characterized in that, The torque sensor with temperature compensation function is configured at the rotor of the torque generating motor to detect the rotor temperature and rotor torque. The torque sensor with temperature compensation function is configured with a calculation method, the calculation method including: Obtain the rotor torque and rotor temperature, generate a compensation factor based on the temperature, and calculate the product of torque and compensation factor, where the product is the torque. The compensation factor is distributed between 0 and 1.

8. The method for controlling drill casing joint parameters as described in claim 1, characterized in that, In step 2, machine vision is used to detect whether the sleeve thread has become tangled.

9. The method for controlling drill casing joint parameters as described in claim 8, characterized in that, Methods for detecting whether thread breakage has occurred in the bushing female thread include: An industrial camera is used to capture an image of the female sleeve buckle. Based on the percentage of pixels occupied by the female sleeve buckle in the image, the shooting distance and focal length of the industrial camera are adjusted so that the percentage of pixels occupied by the female sleeve buckle reaches 95% of the total pixels in the image, and the final image is output. Obtain a standard fraying image, extract the first feature value of the standard fraying image, and extract the second feature value of the final image. Calculate the similarity between the first and second feature values ​​based on cosine similarity. Based on the comparison between similarity and a preset threshold, it is determined whether the sleeve female thread has become taut. If the similarity is less than or equal to the preset threshold, the sleeve female thread has not been frayed; otherwise, the sleeve female thread has been frayed. Each new finished product obtained must meet the first condition, which is that the new finished product has the same model number as the original finished product and the production time is similar, where "similar" means that the interval between the production times is less than or equal to 15 days.

10. A drill casing joint parameter control system, the system being used to execute the drill casing joint parameter control method according to claim 1, characterized in that, Includes a detection module and a control module; The detection module performs a screw-on / unscrew operation based on the finished product according to the first parameter, which includes the sleeve connector parameter and the sleeve female thread parameter. The parameters for the unscrewing operation include torque and number of cycles; Obtain the finished product model, obtain the parameters of the historical tightening and loosening operations corresponding to the finished product model, set the torque and number of cycles, and monitor the torque based on a torque sensor with temperature compensation function; The control module detects whether the sleeve thread has become unraveled; If so, adjust the first parameter and repeat steps 1 to 2 until the sleeve female thread no longer gets tangled. Then bind the adjusted first parameter to the finished product model. If not, then bind the first parameter to the finished product model; Each cycle of steps 1-2 yields a new finished product.

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