Resonant backoff method and system for a casing-collar sub-system

Abstract

The present application relates to the technical field of tooling, and particularly relates to a resonance loosening method and system for a casing-coupling sub-system. The method comprises: obtaining a make-up torque of the casing-coupling sub-system, determining a maximum loosening torque according to the make-up torque; determining basic parameters of the casing-coupling, establishing a finite element model according to the basic parameters, carrying out modal simulation analysis and test measurement according to the finite element model, and determining an inherent frequency of the casing-coupling sub-system, a position of an excitation point and an excitation acceleration; according to the excitation point and the excitation acceleration, a middle / high frequency excitation device is used to apply vibration excitation under the inherent frequency to the casing-coupling sub-system, a larger resonance amplitude and resonance acceleration are excited in the casing-coupling sub-system, a violent transverse or longitudinal swing is generated at the coupling, a loosening effect is generated, the loosening torque of the casing-coupling sub-system is significantly reduced, and efficient unmake-up is ensured.

Description

Technical Field

[0001] This invention relates to the field of tooling technology, and in particular to a resonant loosening method and system for a sleeve-coupling system. Background Technology

[0002] For the redevelopment of old wells or the sealing of abandoned wells, one of the main steps is to remove the already installed casing string. Typically, the casing length can reach hundreds or even thousands of meters. Traditional milling operations use a milling cylinder to mill downwards from the wellhead, which is extremely inefficient, and the casing is milled into scrap, losing its secondary value and resulting in a significant waste of resources. Currently, the casing string installed in the well consists of multiple casings connected by threads. If a torque wrench is used at the wellhead to reverse the uncoupling, and a pulling tool is used in conjunction, the casing can be directly retrieved. However, due to the long service time and complex service environment of the casing downhole, corrosion and adhesion inevitably occur at the threaded connection couplings, greatly increasing the uncoupling torque, even exceeding the maximum load of the torque wrench, thus making uncoupling impossible. Summary of the Invention

[0003] The technical problem to be solved by this invention is to address the shortcomings of existing technologies, specifically the problem of inability to loosen the coupling. Specifically, it provides a resonant loosening method and system for a sleeve-coupling subsystem, as detailed below:

[0004] 1) In a first aspect, the present invention provides a method for resonant loosening of a sleeve-coupling subsystem, the specific technical solution of which is as follows:

[0005] Obtain the maximum uncoupling torque of the sleeve-coupling system;

[0006] Determine the basic parameters of the sleeve-coupling subsystem, and establish a finite element model based on the basic parameters. Based on the finite element model, preliminarily determine the location of the excitation point and the excitation acceleration of the sleeve-coupling subsystem.

[0007] The natural frequency of the sleeve-coupling system was measured using an instrument. Based on the measurement results, the position of the initially determined excitation point and the initially determined excitation acceleration were calibrated to obtain the calibrated position of the excitation point and the calibrated excitation acceleration.

[0008] The sleeve-coupling system is subjected to resonance loosening treatment based on the position of the calibrated excitation point and the calibrated excitation acceleration.

[0009] The beneficial effects of the resonance loosening method for a sleeve-coupling system provided by this invention are as follows:

[0010] Through a series of simulations and experiments, the excitation acceleration and excitation point location of the bushing-coupling system were determined. By using medium / high frequency excitation equipment, a large resonance amplitude and acceleration were generated in the bushing-coupling system, causing violent lateral or longitudinal oscillation at the coupling, resulting in a loosening effect. This significantly reduced the uncoupling torque of the bushing-coupling system and ensured high-efficiency uncoupling.

[0011] Based on the above solution, the present invention can be further improved as follows.

[0012] Furthermore, the method for obtaining the maximum uncoupling torque of the sleeve-coupling subsystem is as follows:

[0013] The maximum uncoupling torque of the sleeve-coupling system is determined by the up-coupling torque of the sleeve-coupling system.

[0014] Furthermore, the basic parameters include: the steel grade of the sleeve in the sleeve-coupling system, the thread type of the coupling in the sleeve-coupling system, the inner diameter of the sleeve in the sleeve-coupling system, and the outer diameter of the sleeve in the sleeve-coupling system.

[0015] Furthermore, the natural frequency of the sleeve-coupling system is measured using an instrument. Based on the measurement results, the initially determined location of the excitation point and the initially determined excitation acceleration are calibrated to obtain the calibrated location of the excitation point and the calibrated excitation acceleration, specifically including:

[0016] The sleeve-coupling system is tested using an excitation hammer to obtain its multiple natural frequencies. These frequencies are then input into the finite element model to calibrate and determine the precise excitation point and acceleration of the sleeve-coupling system. The precise excitation point position obtained after calibration is used as the excitation point position, and the precise excitation acceleration obtained after calibration is used as the excitation acceleration for resonance uncoupling treatment.

[0017] 2) In a second aspect, the present invention also provides a resonant loosening system for a sleeve-coupling subsystem, the specific technical solution of which is as follows:

[0018] The acquisition module is used to: acquire the maximum uncoupling torque of the sleeve-coupling subsystem;

[0019] The determination module is used to: determine the basic parameters of the sleeve-coupling subsystem, establish a finite element model based on the basic parameters, and preliminarily determine the location of the excitation point and the excitation acceleration of the sleeve-coupling subsystem based on the finite element model;

[0020] The calibration module is used to: measure the natural frequency of the sleeve-coupling system using instruments, and calibrate the initially determined position of the excitation point and the initially determined excitation acceleration based on the measurement results, so as to obtain the calibrated position of the excitation point and the calibrated excitation acceleration.

[0021] The processing module is used to perform resonance loosening processing on the sleeve-coupling subsystem based on the position of the calibrated excitation point and the calibrated excitation acceleration.

[0022] Based on the above solution, the present invention can be further improved as follows.

[0023] Furthermore, the method for obtaining the maximum uncoupling torque of the sleeve-coupling subsystem is as follows:

[0024] The maximum uncoupling torque of the sleeve-coupling system is determined by the up-coupling torque of the sleeve-coupling system.

[0025] Furthermore, the basic parameters include: the steel grade of the sleeve in the sleeve-coupling system, the thread type of the coupling in the sleeve-coupling system, the inner diameter of the sleeve in the sleeve-coupling system, and the outer diameter of the sleeve in the sleeve-coupling system.

[0026] Furthermore, the natural frequency of the sleeve-coupling system is measured using an instrument. Based on the measurement results, the initially determined location of the excitation point and the initially determined excitation acceleration are calibrated to obtain the calibrated location of the excitation point and the calibrated excitation acceleration, specifically including:

[0027] The sleeve-coupling system is tested using an excitation hammer to obtain its multiple natural frequencies. These frequencies are then input into the finite element model to calibrate and determine the precise excitation point and acceleration of the sleeve-coupling system. The precise excitation point position obtained after calibration is used as the excitation point position, and the precise excitation acceleration obtained after calibration is used as the excitation acceleration for resonance uncoupling treatment.

[0028] It should be noted that the beneficial effects of the technical solution of the second aspect of the present invention and the corresponding possible implementation can be found in the above description of the technical effects of the first aspect and its corresponding possible implementation, and will not be repeated here. Attached Figure Description

[0029] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0030] Figure 1This is a schematic flowchart of a resonant loosening method for a sleeve-coupling system according to an embodiment of the present invention;

[0031] Figure 2 This is a schematic diagram of the architecture of a resonant loosening system for a sleeve-coupling subsystem according to an embodiment of the present invention;

[0032] Figure 3 This is a schematic diagram of the cross-section of the bushing string. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0034] like Figure 1 As shown, an embodiment of the present invention provides a resonant loosening method for a sleeve-coupling system, comprising the following steps:

[0035] S1, obtain the maximum uncoupling torque of the sleeve-coupling system;

[0036] S2, determine the basic parameters of the sleeve-coupling subsystem, and establish a finite element model based on the basic parameters. Based on the finite element model, preliminarily determine the location of the excitation point and the excitation acceleration of the sleeve-coupling subsystem.

[0037] S3. The natural frequency of the sleeve-coupling system is measured using an instrument. Based on the measurement results, the position of the preliminarily determined excitation point and the preliminarily determined excitation acceleration are calibrated to obtain the calibrated position of the excitation point and the calibrated excitation acceleration.

[0038] S4. Perform resonance loosening treatment on the sleeve-coupling subsystem according to the position of the calibrated excitation point and the calibrated excitation acceleration.

[0039] The beneficial effects of the resonance loosening method for a sleeve-coupling system provided by this invention are as follows:

[0040] Through a series of simulation and experimental methods, a large resonance amplitude and acceleration are excited in the sleeve-coupling system, causing violent lateral or longitudinal oscillation at the coupling, resulting in a loosening effect. This significantly reduces the loosening torque of the sleeve-coupling system and ensures high-efficiency uncoupling.

[0041] The process of obtaining the tightening torque of the sleeve-coupling system and determining the maximum loosening torque based on the tightening torque is as follows:

[0042] like Figure 3 As shown, the x-direction is the pipe length direction, and the y-direction and z-direction are two mutually perpendicular directions of the pipe cross-section. Nodes 1, 2, 3, and 4 are points taken at the 1 / 4 arc of the cross-section, d0 and d...i These are the inner diameter and outer diameter of the tube, respectively.

[0043] Based on the upper torque data of the sleeve-coupling subsystem, estimate the lower torque (≥ upper torque) at the coupling, and determine the maximum achievable uncoupling torque based on the maximum load of the on-site torque wrench.

[0044] The sleeve-coupling subsystem consists of two parts: a sleeve and a cylindrical coupling. The sleeve joint is externally threaded, while the coupling cylinder is internally threaded. The two sleeves are connected together by the coupling.

[0045] The estimation process is as follows: the connection process between the sleeve and the coupling is generally called the upper connection, which is achieved by a torque wrench. The upper connection torque can be read by the reading of the torque wrench.

[0046] The maximum achievable release torque is determined as follows: based on the maximum load of the torque machine on site during the tightening process, the maximum release torque can be obtained, i.e., tightening torque ≤ maximum release torque ≤ maximum load of the torque machine.

[0047] The process of determining the basic parameters of the sleeve-coupling subsystem, establishing a finite element model based on the basic parameters, and initially determining the location of the excitation point and the excitation acceleration of the sleeve-coupling subsystem based on the finite element model is as follows:

[0048] Determine the steel grade of the casing, the thread type at the coupling, the length of the casing string, and the inner and outer diameters of the casing (i.e., Figure 3 (d0 and d1 in the text);

[0049] Steel grade refers to the strength grade of steel pipes. In the petroleum industry, the general unit is ksi, where 1 ksi ≈ 6.895 MPa.

[0050] Steel grades can generally include: 80ksi, 105ksi, and 110ksi.

[0051] The thread type refers to the threaded connection method between the casing and the coupling. Generally, the casing end is connected to the inner wall of the coupling body with a tapered thread, while the coupling end is connected to the casing with a flat thread of the same pitch. This design alleviates stress concentration at the root of the external thread of the tubing in a single tapered thread connection, is less prone to fatigue fracture, and provides a good connection effect.

[0052] Buckle types include: trapezoidal buckle, oblong buckle, short round buckle, etc.

[0053] The bushing string is a long string formed by a cycle of bushing-coupling system-buffer-coupling system.

[0054] A finite element model of the sleeve string-coupling system is established. Based on symmetry, a node is selected for each quarter arc. Figure 3The positions of points 1, 2, 3, and 4 in the model are determined by modal analysis to obtain the multi-order natural frequencies (orders 1 to 10) of the sleeve-coupling system. Based on the results of the multi-order modes, the resonance amplitude and resonance acceleration under different modal orders are calculated, and the position of the excitation point and the excitation acceleration (a0) are analyzed and determined.

[0055] Multimode refers to multiple natural frequencies.

[0056] The calculation in the context of different modal orders refers to the use of finite element modal analysis to calculate the resonance amplitude and resonance acceleration at different natural frequencies.

[0057] The analysis and determination process is as follows:

[0058] Using the finite element method, the placement position of the external exciter (i.e., the excitation point) that can excite the sleeve-coupling system to generate the maximum resonance amplitude and the external exciter acceleration (i.e., the excitation acceleration) that can excite the sleeve-coupling system to generate the maximum resonance acceleration were determined.

[0059] The process of resonantly loosening the sleeve-coupling system based on the location and excitation acceleration is as follows:

[0060] The multi-order natural frequencies of the sleeve string-coupler system were determined using instruments such as excitation hammers, and the results of finite element modal analysis (including but not limited to the magnitude of excitation acceleration and the location of excitation point) were calibrated.

[0061] Among them, the excitation hammer refers to the impact hammer, which is a device for testing the multiple natural frequencies of an object. By installing a sensor on the surface of the object to be tested, the surface of the object is struck, and the multiple natural frequencies of the object are calculated by the response data of the object displayed by the sensor.

[0062] The calibration process involves updating the finite element modal analysis data results using the multi-order natural frequency data obtained from the excitation hammer.

[0063] Based on the results of the finite element modal analysis, the magnitude and location of the excitation acceleration were initially obtained. Subsequently, experimental tests were conducted using methods such as excitation hammers to determine the multiple natural frequencies of the sleeve-coupling system. The experimentally measured multiple natural frequencies were then input into the finite element modal analysis software for a second finite element analysis to calibrate and determine the precise excitation acceleration and excitation point location.

[0064] Based on the results of the calibration modal analysis, the excitation points are determined at the locations (p1, p2, p3...) of the sleeve-coupling subsystem. Medium-frequency / high-frequency excitation equipment is then used to apply load, achieving resonance in the sleeve-coupling system. During this process, the number of excitation devices can be selected according to the actual working conditions. For example, a single excitation device can be used for loading, or multiple excitation devices can be placed at multiple locations such as p1, p2, p3, etc., for simultaneous loading.

[0065] The proposed loading acceleration is the excitation acceleration a0. A0 is adjusted to be freely selected within the range of 0.5g to 10g to excite the sleeve string to resonate.

[0066] 10 per resonance 3 ~10 5 After one vibration cycle, pause the excitation and attempt to unfasten the coil using a torque wrench set to one-half to two-thirds of the upper clamping torque; if unfastening is still not possible, continue resonance for 10 cycles. 3 ~10 5 Try again after one vibration cycle.

[0067] Furthermore, the method for obtaining the maximum uncoupling torque of the sleeve-coupling subsystem is as follows:

[0068] The maximum uncoupling torque of the sleeve-coupling system is determined by the up-coupling torque of the sleeve-coupling system.

[0069] Furthermore, the basic parameters include: the steel grade of the sleeve in the sleeve-coupling system, the thread type of the coupling in the sleeve-coupling system, the inner diameter of the sleeve in the sleeve-coupling system, and the outer diameter of the sleeve in the sleeve-coupling system.

[0070] Furthermore, the natural frequency of the sleeve-coupling system is measured using an instrument. Based on the measurement results, the initially determined location of the excitation point and the initially determined excitation acceleration are calibrated to obtain the calibrated location of the excitation point and the calibrated excitation acceleration, specifically including:

[0071] The sleeve-coupling system is tested using an excitation hammer to obtain its multiple natural frequencies. These frequencies are then input into the finite element model to calibrate and determine the precise excitation point and acceleration of the sleeve-coupling system. The precise excitation point position obtained after calibration is used as the excitation point position, and the precise excitation acceleration obtained after calibration is used as the excitation acceleration for resonance uncoupling treatment.

[0072] like Figure 2 As shown, the present invention also provides a resonant loosening system 200 for a sleeve-coupling system, the specific technical solution of which is as follows:

[0073] The acquisition module 210 is used to: acquire the maximum uncoupling torque of the sleeve-coupling subsystem;

[0074] The determination module 220 is used to: determine the basic parameters of the sleeve-coupling subsystem, establish a finite element model based on the basic parameters, and preliminarily determine the location of the excitation point and the excitation acceleration of the sleeve-coupling subsystem based on the finite element model;

[0075] The calibration module 230 is used to: measure the natural frequency of the sleeve-coupling system using an instrument, calibrate the initially determined position of the excitation point and the initially determined excitation acceleration based on the measurement results, and obtain the calibrated position of the excitation point and the calibrated excitation acceleration.

[0076] Processing module 240 is used to perform resonance loosening processing on the sleeve-coupling subsystem according to the position of the calibrated excitation point and the calibrated excitation acceleration.

[0077] Furthermore, the method for obtaining the maximum uncoupling torque of the sleeve-coupling subsystem is as follows:

[0078] The maximum uncoupling torque of the sleeve-coupling system is determined by the up-coupling torque of the sleeve-coupling system.

[0079] Furthermore, the basic parameters include: the steel grade of the sleeve in the sleeve-coupling system, the thread type of the coupling in the sleeve-coupling system, the inner diameter of the sleeve in the sleeve-coupling system, and the outer diameter of the sleeve in the sleeve-coupling system.

[0080] Furthermore, the natural frequency of the sleeve-coupling system is measured using an instrument. Based on the measurement results, the initially determined location of the excitation point and the initially determined excitation acceleration are calibrated to obtain the calibrated location of the excitation point and the calibrated excitation acceleration, specifically including:

[0081] The sleeve-coupling system is tested using an excitation hammer to obtain its multiple natural frequencies. These frequencies are then input into the finite element model to calibrate and determine the precise excitation point and acceleration of the sleeve-coupling system. The precise excitation point position obtained after calibration is used as the excitation point position, and the precise excitation acceleration obtained after calibration is used as the excitation acceleration for resonance uncoupling treatment.

[0082] It should be noted that the beneficial effects of the resonant loosening system 200 for a sleeve-coupling system provided in the above embodiments are the same as those of the resonant loosening method for a sleeve-coupling system described above, and will not be repeated here. Furthermore, the system provided in the above embodiments is only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the system can be divided into different functional modules according to the actual situation to complete all or part of the functions described above. In addition, the system and method embodiments provided in the above embodiments belong to the same concept, and their specific implementation process is detailed in the method embodiments, and will not be repeated here.

[0083] In an exemplary embodiment, a computer program product or computer program is also provided, comprising computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform any of the methods described above.

[0084] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and represent a limitation on a specific order or sequence. Where appropriate, the order of use for similar objects can be interchanged so that the embodiments of this application described herein can be implemented in an order other than that shown or described.

[0085] Those skilled in the art will recognize that this invention can be implemented as a system, method, or computer program product. Therefore, this disclosure can be specifically implemented in the following forms: it can be entirely hardware, entirely software (including firmware, resident software, microcode, etc.), or a combination of hardware and software, generally referred to herein as a "circuit," "module," or "system." Furthermore, in some embodiments, this invention can also be implemented as a computer program product in one or more computer-readable media containing computer-readable program code.

[0086] Any combination of one or more computer-readable media may be used. A computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this document, a computer-readable storage medium can be any tangible medium that contains or stores a program that can be used by or in connection with an instruction execution system, apparatus, or device.

[0087] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A resonant loosening method for a sleeve-coupling system, characterized in that, include: Obtain the maximum uncoupling torque of the sleeve-coupling system; The basic parameters of the sleeve-coupling subsystem are determined, and a finite element model is established based on the basic parameters. A finite element model of the sleeve string-coupling system is established. According to the symmetry, a node is selected for each 1 / 4 arc. The modal analysis method is used to obtain the multiple natural frequencies of the sleeve-coupling system. Based on the results of the multiple modes, the resonance amplitude and resonance acceleration under different modal orders are calculated. The location of the excitation point and the excitation acceleration are analyzed and determined. Multimode refers to multiple natural frequencies; The calculation in the case of different modal orders refers to: using the finite element modal analysis method to calculate the resonance amplitude and resonance acceleration at different natural frequencies; The analysis and determination process is as follows: Using the finite element method, the location of the excitation point that can excite the sleeve-coupler system to generate the maximum resonance amplitude and the excitation acceleration that can excite the sleeve-coupler system to generate the maximum resonance acceleration were obtained; The natural frequency of the sleeve-coupling system was measured using an instrument. Based on the measurement results, the position of the initially determined excitation point and the initially determined excitation acceleration were calibrated to obtain the calibrated position of the excitation point and the calibrated excitation acceleration. The sleeve-coupling system is subjected to resonance loosening treatment based on the position of the calibrated excitation point and the calibrated excitation acceleration.

2. The resonant loosening method for a sleeve-coupling system according to claim 1, characterized in that, The method for obtaining the maximum uncoupling torque of the sleeve-coupling subsystem is as follows: The maximum uncoupling torque of the sleeve-coupling system is determined by the up-coupling torque of the sleeve-coupling system.

3. The resonant loosening method for a sleeve-coupling system according to claim 1, characterized in that, The basic parameters include: the steel grade of the sleeve in the sleeve-coupling system, the thread type of the coupling in the sleeve-coupling system, the inner diameter of the sleeve in the sleeve-coupling system, and the outer diameter of the sleeve in the sleeve-coupling system.

4. A resonant loosening method for a sleeve-coupling system according to any one of claims 1-3, characterized in that, The natural frequency of the sleeve-coupling system was measured using an instrument. Based on the measurement results, the initially determined location of the excitation point and the initially determined excitation acceleration were calibrated to obtain the calibrated location of the excitation point and the calibrated excitation acceleration, specifically including: The sleeve-coupling system is tested using an excitation hammer to obtain its multiple natural frequencies. These frequencies are then input into the finite element model to calibrate and determine the precise excitation point and acceleration of the sleeve-coupling system. The precise excitation point position obtained after calibration is used as the excitation point position, and the precise excitation acceleration obtained after calibration is used as the excitation acceleration for resonance uncoupling treatment.

5. A resonant loosening system for a sleeve-coupling system, employing the resonant loosening method for a sleeve-coupling system as described in claim 1, characterized in that... The system includes: The acquisition module is used to: acquire the maximum uncoupling torque of the sleeve-coupling subsystem; The determination module is used to: determine the basic parameters of the sleeve-coupling subsystem, establish a finite element model based on the basic parameters, and preliminarily determine the location of the excitation point and the excitation acceleration of the sleeve-coupling subsystem based on the finite element model; The calibration module is used to: measure the natural frequency of the sleeve-coupling system using instruments, and calibrate the initially determined position of the excitation point and the initially determined excitation acceleration based on the measurement results, so as to obtain the calibrated position of the excitation point and the calibrated excitation acceleration. The processing module is used to perform resonance loosening processing on the sleeve-coupling subsystem based on the position of the calibrated excitation point and the calibrated excitation acceleration.

6. The resonant loosening system of a sleeve-coupling system according to claim 5, characterized in that, The method for obtaining the maximum uncoupling torque of the sleeve-coupling subsystem is as follows: The maximum uncoupling torque of the sleeve-coupling system is determined by the up-coupling torque of the sleeve-coupling system.

7. The resonant loosening system of a sleeve-coupling system according to claim 5, characterized in that, The basic parameters include: the steel grade of the sleeve in the sleeve-coupling system, the thread type of the coupling in the sleeve-coupling system, the inner diameter of the sleeve in the sleeve-coupling system, and the outer diameter of the sleeve in the sleeve-coupling system.

8. A resonant loosening system for a sleeve-coupling system according to any one of claims 5-7, characterized in that, The natural frequency of the sleeve-coupling system was measured using an instrument. Based on the measurement results, the initially determined location of the excitation point and the initially determined excitation acceleration were calibrated to obtain the calibrated location of the excitation point and the calibrated excitation acceleration, specifically including: The sleeve-coupling system is tested using an excitation hammer to obtain its multiple natural frequencies. These frequencies are then input into the finite element model to calibrate and determine the precise excitation point and acceleration of the sleeve-coupling system. The precise excitation point position obtained after calibration is used as the excitation point position, and the precise excitation acceleration obtained after calibration is used as the excitation acceleration for resonance uncoupling treatment.

Images