Sliding bearing-rotor system stability test system and method under impact load

Abstract

The invention discloses a sliding bearing-rotor system stability test system and method under an impact load, and relates to the field of rotating machinery test in mechanical engineering. According to the technical scheme, different types of impact loads are applied through a vibration acceleration platform, and starting, stopping or external impact force in actual working conditions is simulated. In the testing process, a high-precision sensor and a multi-channel acquisition board card are used for monitoring the vibration characteristic and the rotating speed of the system in real time, it is guaranteed that signals of different positions and types can be synchronously acquired, and comprehensive system state information is provided. Then, in combination with time domain and frequency domain analysis technologies, key features are extracted from mass data by applying an advanced Fourier transform algorithm, the resonant frequency, modal characteristics and potential fault modes of the system are identified, and accurate evaluation of the stability of the system is realized. Experimental results show that the real-time monitoring and analysis method can effectively improve the stability test precision of the sliding bearing-rotor system under the impact load, and provides powerful technical support for engineering application. The method is used for evaluating the stability of the sliding bearing-rotor system under the impact load.

Description

Technical Field

[0001] The invention relates to the field of rotating machinery testing in mechanical engineering, and in particular to a system and method for testing the stability of a sliding bearing-rotor system under an impact load. Background Art

[0002] Sliding bearing-rotor systems are widely used in various industrial equipment, such as steam turbines, compressors, pumps, etc. The working performance of these systems is directly related to the safety and reliability of the entire mechanical equipment. In actual operating environments, sliding bearing-rotor systems may encounter sudden starts, stops or external impact forces. These impact loads will cause instantaneous high stress and large deformation in the system, which will in turn cause vibration, noise, wear and even failure, posing a challenge to the stability of the system. Especially in some extreme working conditions, such as aerospace, marine engineering and heavy industrial equipment, the impact load poses a particularly prominent challenge to the stability of the system.

[0003] At present, the stability test methods for sliding bearing-rotor systems are mainly focused on evaluation under static load and steady-state operating conditions. Common test methods include: evaluating the bearing's load capacity and friction characteristics by applying constant axial and radial loads; using an exciter to apply periodic or random dynamic loads to simulate the vibration environment under normal operating conditions; and evaluating the fatigue life of bearings and rotors through long-term cyclic loading.

[0004] Existing test methods often cannot accurately simulate the impact loads under actual working conditions, resulting in deviations between the test results and the actual situation, making it difficult to fully evaluate the dynamic response characteristics and stability of the sliding bearing-rotor system. In addition, traditional methods often lack precision, have limited scope of application, and are difficult to process data. In order to achieve a more realistic test environment, in some cases it is necessary to build a large test bench, which increases a lot of manpower investment and test time.

[0005] For example, document number CN115791168A is an existing patent document, which discloses a simulation test system and method for sliding bearings, which includes an environmental simulation device providing a first simulated working environment and a second simulated working environment for the sliding bearing, collecting feedback signals of the sliding bearing in the first simulated working environment and the second simulated working environment through a signal acquisition device, controlling the first simulated working environment and the second simulated working environment according to the feedback signal, and analyzing the feedback signal to obtain the test result of the sliding bearing, so as to realize process simulation and dynamic simulation of the real working condition and improve the accuracy of the sliding bearing test. However, it is only for sliding bearings, not suitable for the test of sliding bearing-rotor system, and its simulated working environment is not the working condition under impact load. Summary of the invention

[0006] The technical problems to be solved by the present invention are:

[0007] The prior art does not propose to perform stability testing of the bearing-rotor system under impact load conditions, and cannot comprehensively and accurately evaluate the bearing-rotor system under impact load conditions, and has not been able to solve the problems of low test accuracy, difficult data processing, complex test bench construction, and excessive resource investment of the sliding bearing-rotor system under impact load conditions. To this end, the present invention provides a stability testing system and method for a sliding bearing-rotor system under impact load.

[0008] The present invention adopts the following technical solutions to solve the above technical problems:

[0009] A sliding bearing-rotor system stability test system under impact load, the stability test system is used to test the stability of the sliding bearing-rotor system under the working condition under impact load; the stability test system comprises a sliding bearing-rotor system test bench, an impact load applying device, and a monitoring and measuring system;

[0010] The sliding bearing-rotor system test bench comprises a drive motor (3), a coupling (4), a thrust bearing assembly (5), at least two radial bearing seat assemblies (6), eddy current displacement sensor brackets (7) having the same number as the radial bearing seat assemblies (6), a drive motor bracket (8) and a base plate (9); the thrust bearing assembly (5) comprises two thrust bearings (5-1), a thrust plate (thrust plate) (5-2) located between the two thrust bearings (5-1), two thrust bearing end covers (5-3) installed on the outside of the two thrust bearings (5-1), and a thrust bearing seat (5-4) installed on the base plate (9); each radial bearing seat assembly (6) comprises a radial sliding bearing (6-1), a thrust plate (5-2) installed on the radial sliding bearing (6-1), and a thrust bearing seat (5-4) installed on the base plate (9). 1) radial sliding bearing end covers (6-2) on both sides and a radial sliding bearing seat (6-3) installed on a base plate (9); each eddy current displacement sensor bracket (7) is installed on the base plate (9) and close to a corresponding radial bearing seat assembly (6); the thrust bearing assembly (5) is close to the coupling (4), and the at least two radial bearing seat assemblies (6) are far away from the coupling (4); the motor (3) is installed on the base plate (9) through the driving motor bracket 8, the output shaft of the motor (3) is connected to the rotating shaft (1) through the coupling (4), and the rotating shaft (1) is installed on the two thrust bearings (5-1) and each radial sliding bearing (6-1) in sequence; the wheel disc (2-1) is installed at a specific position of the rotating shaft (1) according to design requirements;

[0011] The impact load applying device is a vibration acceleration platform for outputting different types of impact loads. The sliding bearing-rotor system test bench and the object to be tested thereon are installed on the vertical extension table of the vibration acceleration platform. By selecting one of the classical impact, random impact, and swept frequency impact on the vibration acceleration platform, and inputting acceleration, frequency, and time parameters, the impact load is applied to the sliding bearing-rotor system test bench on which the object to be tested is installed.

[0012] The monitoring and measuring system comprises eddy current displacement sensors (10) whose number is twice that of radial sliding shafts, photoelectric speed sensors (11), an acquisition board (12), and a processor (13). Each eddy current displacement sensor bracket (7) is equipped with two eddy current displacement sensors which are arranged in 90-degree directions to each other. The photoelectric speed sensor is installed on the output shaft of the driving motor (3) to measure its speed. The processor (13) is configured with a test program for the stability of the sliding bearing-rotor system under impact load. The eddy current displacement sensor (10) is used to measure the relative displacement between the rotating shaft (1) and the sensor, and convert it into a voltage signal proportional to the displacement. The voltage signal is transmitted to the processor for real-time analysis after signal conditioning and analog-to-digital conversion by the acquisition board (12). analysis and processing; at the same time, the photoelectric speed sensor (11) generates a pulse signal proportional to the speed by detecting the rotation of the rotating shaft (1), and the pulse signal is transmitted to the processor (13) for real-time analysis and processing after signal conditioning and analog-to-digital conversion by the acquisition board (12); the test program of the processor (13) simultaneously analyzes and processes the collected voltage signal and pulse signal, and obtains an axis trajectory diagram of the rotating shaft (1) rotating one circle and a vibration spectrum diagram of the sliding bearing-rotor system that can be displayed on the display interface, and judges whether the vibration amplitude of the rotating shaft exceeds the design safety range, whether there are abnormal frequency components, and whether the axis trajectory diverges according to the axis trajectory diagram and the vibration spectrum diagram, thereby obtaining whether the stability of the sliding bearing-rotor system under the impact load is good.

[0013] A method for testing the stability of a sliding bearing-rotor system under an impact load, the method being implemented based on the above stability testing system, the object to be tested of the stability testing method being a sliding bearing-rotor system, and the working condition being under an impact load; the sliding bearing-rotor system comprising a rotating shaft (1), a plurality of wheel disc assemblies (2), each wheel disc assembly (2) comprising a wheel disc (2-1) and a tension sleeve (2-2), each wheel disc being mounted on the rotating shaft (1) via a corresponding tension sleeve; the method comprising the following steps:

[0014] S1. Installation and configuration: The tested sliding bearing-rotor system is installed on the sliding bearing-rotor system test bench, and then the entire sliding bearing-rotor system test bench is installed on the impact load applying device, and the impact load applying device for simulating impact conditions is connected to the ground;

[0015] S2. Setting the loading program: through the host computer of the impact load applying device, according to the actual working conditions or the preset load spectrum, use the interactive interface of the host computer to set the loading parameters of the impact load applying device (vibration acceleration platform): impact type, acceleration, frequency;

[0016] S3, start the drive motor; start the drive motor (3) of the sliding bearing-rotor system test bench, make the shaft reach a predetermined speed, and keep stable operation, monitor the shaft speed and vibration amplitude through the test program in the monitoring and measurement system processor, and ensure that the speed fluctuates within the allowable range;

[0017] S4, start the impact load applying device (vibration acceleration platform); apply the impact load to the sliding bearing-rotor system according to the loading program preset in step S2, and the control system of the impact load applying device will adjust the output of each actuator in real time to ensure that the load change meets the set requirements;

[0018] S5, data acquisition: data acquisition is performed through the processor of the monitoring and measuring system. During the entire test process, the eddy current displacement sensor (10) acquires the displacement and vibration parameters of the rotating shaft (1) in real time; the photoelectric rotation speed sensor (11) acquires the rotation speed of the rotating shaft (1) in real time. The eddy current displacement sensor (10) and the photoelectric rotation speed sensor (11) synchronously record the data of multiple channels at a high sampling rate through an acquisition board to ensure the integrity and accuracy of the data;

[0019] S6. Data processing: Data processing is performed through the processor of the monitoring and measurement system. The collected data is preliminarily processed using the test program: filtering and calibration; the collected data is deeply analyzed using the test program to extract characteristic values: time domain diagram, spectrum diagram, speed, axis trajectory; the data at various speeds is processed using the MATLAB script file and a report is generated to provide an intuitive and concise analysis of the stability of the sliding bearing-rotor system under impact loads;

[0020] S7. Data analysis: Data analysis is performed through the processor of the monitoring and measurement system. Based on the extracted characteristic values, the stability of the sliding bearing-rotor system under impact load is evaluated. The specific evaluation indicators are whether the vibration amplitude exceeds the safety range, whether there are abnormal frequency components, and whether the axis trajectory diverges.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention applies impact loads of different types and frequencies through a vibration acceleration platform to simulate the start, stop or external impact force in actual working conditions. During the test, high-precision sensors (such as eddy current displacement sensors, photoelectric speed sensors) and multi-channel acquisition boards are used to monitor the vibration characteristics and speed of the system in real time to ensure that signals of different positions and types can be collected synchronously and provide comprehensive system status information. Then, combining time domain and frequency domain analysis techniques, the fast Fourier transform (FFT) algorithm is applied to extract key features from massive data, identify the system's resonant frequency, modal characteristics and potential failure modes, and achieve an accurate assessment of the system's stability. Experimental results show that the real-time monitoring and analysis method of the present invention can effectively improve the stability test accuracy of the sliding bearing-rotor system under impact loads, providing strong technical support for engineering applications. The specific advantages are manifested in the following aspects:

[0023] 1) By applying an impact load in the direction of gravity through a vibration acceleration platform, the dynamic response of the sliding bearing-rotor system in actual work can be truly reproduced; compared with the traditional method, the present invention can simulate the impact load more accurately, ensure that the test conditions are highly consistent with the actual operating environment, and avoid errors caused by simplified assumptions;

[0024] 2) High-speed, high-resolution data acquisition equipment is used to synchronously record the output signals of multiple sensors to ensure the integrity and accuracy of the data; traditional testing methods often lead to data loss or inaccuracy due to insufficient sampling rate or limited sensor accuracy, and the present invention effectively solves these problems through advanced data acquisition technology.

[0025] 3) Use the graphical programming language to process the test data in real time and extract features; simplify the data interpretation process through frequency domain analysis, time-frequency analysis and other means, identify potential failure modes and abnormal conditions, provide early warnings and make improvement suggestions.

[0026] 4) Key components such as sensors and data acquisition cards all support plug-and-play functionality, allowing users to quickly start testing without complex configuration. This feature makes the construction and operation of the test bench easier and reduces the possibility of human error.

[0027] The invention is used to evaluate the stability of a sliding bearing-rotor system under impact load. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention can be better understood by referring to the following description given in conjunction with the accompanying drawings, which together with the following detailed description are included in this specification and form a part of this specification, and are used to further illustrate the preferred embodiments of the present invention and explain the principles of the present invention.

[0029] Figure 1 This is a front view of a sliding bearing-rotor system stability test system under impact load according to the present invention (the impact load applying device is located below the bottom plate 9 in the figure);

[0030] Figure 2 A three-dimensional diagram of a sliding bearing-rotor system stability test system under impact load according to the present invention;

[0031] Figure 3 An exploded view of the wheel assembly of the present invention;

[0032] Figure 4 An exploded view of the radial bearing seat assembly of the present invention;

[0033] Figure 5 An exploded view of the thrust bearing assembly of the present invention;

[0034] Figure 6 This is a schematic diagram of the acquisition board and processor of the present invention;

[0035] Figure 7 It is a schematic diagram of the flow of a system and method for testing the stability of a sliding bearing-rotor system under an impact load according to the present invention;

[0036] Figure 8 This is a diagram verifying the technical effects of the present invention.

[0037] Fig. 9 It is a schematic diagram comparing the stability test results of the sliding bearing-rotor system under the impact load described in the present invention. DETAILED DESCRIPTION

[0038] Combined with Figures 1 to 9 To illustrate the implementation of a sliding bearing-rotor system stability test system and method under impact load described in the present invention:

[0039] The present invention provides a sliding bearing-rotor system stability measurement system under impact load, comprising a sliding bearing-rotor system test bench, an impact load applying device, and a monitoring and measuring system. The impact load applying device can be a vibration acceleration platform produced by Suzhou Weibo Testing Instrument Co., Ltd., model ATS-53 / HE0606, which can perform classical impact (sine wave impact, half-sine wave impact), random impact, and frequency sweep impact;

[0040] The sliding bearing-rotor system stability test system under impact load described in this embodiment is used to test the stability of the sliding bearing-rotor system under the working condition under impact load; the stability test system includes a sliding bearing-rotor system test bench, an impact load application device, and a monitoring and measurement system;

[0041] The sliding bearing-rotor system test bench comprises a drive motor 3, a coupling 4, a thrust bearing assembly 5, at least two radial bearing seat assemblies 6, eddy current displacement sensor brackets 7 having the same number as the radial bearing seat assemblies 6, a drive motor bracket 8 and a base plate 9; the thrust bearing assembly 5 comprises two thrust bearings 5-1, a thrust plate (thrust plate) 5-2 located between the two thrust bearings 5-1, two thrust bearing end covers 5-3 installed on the outside of the two thrust bearings 5-1 and a thrust bearing seat 5-4 installed on the base plate 9; each radial bearing seat assembly 6 comprises a radial sliding bearing 6-1, a thrust plate 5-2 installed on the radial sliding bearing The radial sliding bearing end covers 6-2 on both sides of 6-1 and the radial sliding bearing seats 6-3 installed on the base plate 9; each eddy current displacement sensor bracket 7 is installed on the base plate 9 and close to a corresponding radial bearing seat assembly 6; the thrust bearing assembly 5 is close to the coupling 4, and the at least two radial bearing seat assemblies 6 are far away from the coupling 4. The motor 3 is installed on the base plate 9 through the driving motor bracket 8, and the output shaft of the motor 3 is connected to the rotating shaft 1 through the coupling 4. The rotating shaft 1 is installed on two thrust bearings 5-1 and each radial sliding bearing 6-1 in turn; the wheel disc 2-1 is installed at a specific position of the rotating shaft 1 according to the design requirements;

[0042] The impact load applying device is a vibration acceleration platform for outputting different types of impact loads. The sliding bearing-rotor system test bench and the object to be tested thereon are installed on the vertical extension table of the vibration acceleration platform. By selecting one of the classical impact, random impact, and swept frequency impact on the vibration acceleration platform, and inputting acceleration, frequency, and time parameters, the impact load is applied to the sliding bearing-rotor system test bench on which the object to be tested is installed.

[0043] The monitoring and measuring system comprises eddy current displacement sensors 10, which are twice the number of radial sliding shafts, photoelectric speed sensors 11, acquisition boards 12, and processors 13. Each eddy current displacement sensor bracket 7 is equipped with two eddy current displacement sensors in directions of 90 degrees to each other. The photoelectric speed sensor is installed on the output shaft of the driving motor 3 to measure its speed. The processor 13 is configured with a test program for the stability of the sliding bearing-rotor system under impact load. The eddy current displacement sensor (10) is used to measure the relative displacement between the rotating shaft 1 and the sensor, and convert it into a voltage signal proportional to the displacement. After the voltage signal is conditioned and converted into analog-to-digital by the acquisition board 12, it is transmitted to the processor for real-time analysis and Processing; at the same time, the photoelectric speed sensor 11 generates a pulse signal proportional to the speed by detecting the rotation of the shaft 1. The pulse signal is transmitted to the processor 13 for real-time analysis and processing after signal conditioning and analog-to-digital conversion by the acquisition board 12; the test program of the processor 13 simultaneously analyzes and processes the collected voltage signal and pulse signal, and obtains an axis trajectory diagram of the shaft 1 rotating one circle and a vibration spectrum diagram of the sliding bearing-rotor system that can be displayed on the display interface. According to the axis trajectory diagram and the vibration spectrum diagram, it is judged whether the vibration amplitude of the shaft exceeds the designed safety range, whether there are abnormal frequency components, and whether the axis trajectory diverges, thereby obtaining whether the stability of the sliding bearing-rotor system under impact load is good.

[0044] The thrust bearing assembly also includes a sleeve 5-5 and a locking nut 5-6. Two thrust bearings 5-1 are installed on the thrust bearing seat 5-4, and the thrust plate 5-2 is installed on the inner side (that is, installed between the two thrust bearings 5-1). The thrust plate 5-2 is sleeved on the rotating shaft 1. The sleeve 5-5 is installed between a thrust bearing 5-1 close to the coupling 4 and the rotating shaft 1. The locking nut 5-6 is installed on the rotating shaft 1 close to the coupling 4. The locking nut 5-6 is axially limited by the sleeve 5-5 (the locking nut 5-6 fixes the sleeve 5-5 and the thrust plate 5-2), so that the thrust plate 5-2 rotates with the rotating shaft 1. The bearing end covers installed on both sides of the thrust bearing seat are used to prevent foreign matter from entering the bearing.

[0045] The radial bearing seat assembly includes a radial sliding bearing, a radial bearing seat, and a bearing end cover. The radial sliding bearing is fixed on the radial bearing seat. The bearing end covers are installed on both sides of the radial bearing seat to prevent foreign matter from entering the bearing. The radial bearing seat is fixed on the bottom plate. The rotating shaft is installed inside the radial bearing to support rotation.

[0046] A coupling is installed at the output shaft (spindle) of the driving motor, and the coupling is connected to the end of the rotating shaft. The wheel assembly includes a wheel and a tension sleeve, and the tension sleeve is used to be placed inside the wheel. The tension sleeve and the wheel (disc) are installed on the rotating shaft by screws, and the bottom plate 9 is rigidly fixed on the vibration acceleration platform by bolts;

[0047] The impact load application device adopts the vibration acceleration platform produced by Suzhou Weibo Testing Instrument Co., Ltd., model ATS-53 / HE0606, which can perform classic impact, random impact, and sweep frequency impact. Before measurement, it is connected to the ground through expansion bolts to maintain sufficient rigidity to avoid significant errors in the test measurement; the operating parameters are rated acceleration 1000m / s 2 , frequency range 2~3000Hz, maximum displacement 51mm; fix the above-assembled sliding bearing rotor system test bench (the sliding bearing-rotor system test bench after installing the object to be tested) to the vibration acceleration platform by bolts, and input different acceleration and frequency parameters through the vibration acceleration platform control cabinet to apply impact load to the sliding bearing rotor system test bench;

[0048] The eddy current displacement sensor 10 is installed horizontally and vertically on the sensor bracket, the sensor bracket is installed at the radial bearing support position, the photoelectric speed sensor is installed on the sensor bracket, and the sensor bracket is fixed on the supporting structure; the acquisition board model is NI USB-4432, which can collect data on speed and vibration; the test program can collect, process and display vibration and speed signals in real time.

[0049] A method for testing the stability of a sliding bearing-rotor system under an impact load, the method is implemented based on a system for testing the stability of a sliding bearing-rotor system under an impact load, the object of the stability measurement method is a sliding bearing-rotor system, and the working condition is under an impact load; the sliding bearing-rotor system comprises a rotating shaft 1, a plurality of wheel disc assemblies 2, each wheel disc assembly 2 comprises a wheel disc 2-1 and a tension sleeve 2-2, and each wheel disc is mounted on the rotating shaft 1 through a corresponding tension sleeve;

[0050] The stability testing method comprises the following steps:

[0051] S1. Installation and configuration: The tested sliding bearing-rotor system is installed on the sliding bearing-rotor system test bench, and then the entire sliding bearing-rotor system test bench is installed on the impact load application device, and the impact load application device for simulating impact conditions is connected to the ground; (S1 also includes: assembling all components on the test bench according to design requirements, ensuring that all components are firmly connected and the sensor position is accurate; checking whether each actuator of the vibration acceleration platform is working properly, and performing preload tests to ensure the stability of the system;)

[0052] S2. Setting the loading program: through the host computer of the impact load applying device, according to the actual working conditions or the preset load spectrum, use the interactive interface of the host computer to set the loading parameters of the impact load applying device (vibration acceleration platform): impact type, acceleration, frequency;

[0053] S3, start the drive motor; start the drive motor 3 of the sliding bearing-rotor system test bench, make the shaft reach a predetermined speed, and keep stable operation, monitor the shaft speed and vibration amplitude through the test program in the monitoring and measurement system processor, and ensure that the speed fluctuates within the allowable range;

[0054] S4, start the impact load applying device (vibration acceleration platform); apply the impact load to the sliding bearing-rotor system according to the loading program preset in step S2, and the control system of the impact load applying device will adjust the output of each actuator in real time to ensure that the load change meets the set requirements;

[0055] S5, data acquisition: data acquisition is performed through the processor of the monitoring and measuring system. During the entire test process, the eddy current displacement sensor 10 collects the displacement and vibration parameters of the shaft 1 in real time; the photoelectric speed sensor 11 collects the speed of the shaft 1 in real time. The eddy current displacement sensor 10 and the photoelectric speed sensor 11 synchronously record the data of multiple channels at a high sampling rate through the acquisition board to ensure the integrity and accuracy of the data;

[0056] S6. Data processing: Data processing is performed through the processor of the monitoring and measurement system. The collected data is preliminarily processed using the test program: filtering and calibration; the collected data is deeply analyzed using the test program to extract characteristic values: time domain diagram, spectrum diagram, speed, axis trajectory; the data at various speeds is processed using the MATLAB script file and a report is generated to provide an intuitive and concise analysis of the stability of the sliding bearing rotor system under impact loads;

[0057] S7. Data analysis: Data analysis is performed through the processor of the monitoring and measurement system. Based on the extracted characteristic values, the stability of the sliding bearing-rotor system under impact load is evaluated. The specific evaluation indicators are whether the vibration amplitude exceeds the safety range, whether there are abnormal frequency components, and whether the axis trajectory diverges.

[0058] The present invention discloses a system and method for testing the stability of a sliding bearing-rotor system under an impact load. Figure 7 The process is as follows: under impact load conditions, the stability data of the sliding bearing-rotor system is collected by using an eddy current displacement sensor 10 and a photoelectric speed sensor 11; the data collected by the above sensors is transmitted to a processor 13 through a data acquisition board 12; the eddy current displacement sensor and the photoelectric speed sensor used are calibrated to ensure that the voltage signal and the pulse signal can be accurately converted into the corresponding displacement and rotation speed, and necessary filtering is performed in the process to eliminate noise interference; for the experimental data obtained after preliminary processing, the Hanning window function is used for weighting and then a fast Fourier transform (FFT) is performed to improve the frequency resolution and reduce the spectrum leakage phenomenon; the data that has completed the FFT conversion is deeply analyzed, the characteristic values ​​are extracted from it, and the time domain diagram, the spectrum diagram, the axis trajectory and the rotation speed are generated; through the MATLAB script program, a comprehensive report including the time domain diagram, the frequency domain diagram, the axis trajectory and the rotation speed is automatically generated, so as to more conveniently evaluate the stability of the sliding bearing-rotor system under complex alternating loads.

[0059] For verification of the technical effects of the present invention, please refer to Figure 8 , Figure 8 The test results of the sliding bearing-rotor system under impact load using the test system method of the present invention are shown, including time domain diagram, frequency domain diagram, axis trajectory and speed. Analysis can be performed based on the characteristic values ​​extracted from the test program to check whether there are abnormal frequency components, whether the vibration amplitude exceeds the safe range, and whether the axis trajectory has divergence, so as to evaluate whether the stability of the sliding bearing-rotor system under impact load is good. Figure 8 As shown in the figure, after the vibration acceleration platform is started, under the half-sine wave type impact, the impact load is 2g and the pulse width is 6ms. When the shaft speed is 5882r / min, the following phenomena are observed: the signal in the time domain diagram is an irregular sine waveform; the axis trajectory is chaotic and has no obvious rules; in the frequency domain diagram, in addition to the rotation frequency of the shaft, abnormal low-frequency components also appear, and the vibration amplitude is significantly higher than the rotation frequency amplitude. Based on the above characteristics, it can be judged that the stability of the sliding bearing-rotor system is close to the instability boundary.

[0060] The comparison diagram of the stability test results of the sliding bearing-rotor system under the impact load of the present invention is shown in FIG. Fig. 9 . The comprehensive report automatically generated by the MATLAB script file includes information such as time domain diagram, frequency domain diagram, shaft trajectory and speed. The test type is half-sine wave impact, the impact load is 8g, and the pulse width is 6ms. When the shaft speed is 5460r / min and there is no impact, the time domain diagram shows a stable sine waveform; there is no obvious abnormal frequency in the frequency domain diagram; the shaft trajectory is a stable ellipse. Under the impact at the shaft speed of 5520r / min, the originally stable sine waveform evolves into a sharp peak and quickly decays into a sine waveform; in the frequency domain diagram, abnormal low frequency and high vibration amplitude appear; the shaft trajectory evolves from a stable ellipse to an obvious envelope shape. At the shaft speed of 5580r / min, the time domain diagram shows obvious non-sinusoidal wave characteristics; the frequency domain diagram shows abnormal low frequency and high vibration amplitude; the shaft trajectory evolves from a stable ellipse to a divergent petal shape, which is at the boundary of instability. These changes make it more convenient and intuitive to evaluate the stability of the sliding bearing-rotor system under impact load.

[0061] Although the present invention has been described according to a limited number of embodiments, it will be apparent to those skilled in the art, with the benefit of the above description, that other embodiments are contemplated within the scope of the invention thus described. The disclosure of the present invention is intended to be illustrative rather than restrictive of the scope of the invention, which is defined by the appended claims.

Claims

1. A sliding bearing-rotor system stability test system under impact load, characterized in that: The stability test system is used to test the stability of the sliding bearing-rotor system under the working condition of the impact load; the stability test system includes a sliding bearing-rotor system test bench, an impact load applying device, and a monitoring and measuring system; The sliding bearing-rotor system test bench comprises a drive motor (3), a coupling (4), a thrust bearing assembly (5), at least two radial bearing seat assemblies (6), eddy current displacement sensor brackets (7) having the same number as the radial bearing seat assemblies (6), a drive motor bracket (8) and a base plate (9); the thrust bearing assembly (5) comprises two thrust bearings (5-1), a thrust plate (thrust plate) (5-2) located between the two thrust bearings (5-1), two thrust bearing end covers (5-3) installed on the outside of the two thrust bearings (5-1), and a thrust bearing seat (5-4) installed on the base plate (9); each radial bearing seat assembly (6) comprises a radial sliding bearing (6-1), a thrust plate (5-2) installed on the radial sliding bearing (6-1), and a thrust bearing seat (5-4) installed on the base plate (9). 1) radial sliding bearing end covers (6-2) on both sides and a radial sliding bearing seat (6-3) installed on a base plate (9); each eddy current displacement sensor bracket (7) is installed on the base plate (9) and close to a corresponding radial bearing seat assembly (6); the thrust bearing assembly (5) is close to the coupling (4), and the at least two radial bearing seat assemblies (6) are far away from the coupling (4); the motor (3) is installed on the base plate (9) through the driving motor bracket 8, the output shaft of the motor (3) is connected to the rotating shaft (1) through the coupling (4), and the rotating shaft (1) is installed on the two thrust bearings (5-1) and each radial sliding bearing (6-1) in sequence; the wheel disc (2-1) is installed at a specific position of the rotating shaft (1) according to design requirements; The impact load applying device is a vibration acceleration platform for outputting different types of impact loads. The sliding bearing-rotor system test bench and the object to be tested thereon are installed on the vertical extension table of the vibration acceleration platform. By selecting one of the classical impact, random impact, and swept frequency impact on the vibration acceleration platform, and inputting acceleration, frequency, and time parameters, the impact load is applied to the sliding bearing-rotor system test bench on which the object to be tested is installed. The monitoring and measuring system comprises eddy current displacement sensors (10) whose number is twice that of radial sliding shafts, photoelectric speed sensors (11), an acquisition board (12), and a processor (13). Each eddy current displacement sensor bracket (7) is equipped with two eddy current displacement sensors which are arranged in 90-degree directions to each other. The photoelectric speed sensor is installed on the output shaft of the driving motor (3) to measure its speed. The processor (13) is configured with a test program for the stability of the sliding bearing-rotor system under impact load. The eddy current displacement sensor (10) is used to measure the relative displacement between the rotating shaft (1) and the sensor, and convert it into a voltage signal proportional to the displacement. The voltage signal is transmitted to the processor for real-time analysis after signal conditioning and analog-to-digital conversion by the acquisition board (12). analysis and processing; at the same time, the photoelectric speed sensor (11) generates a pulse signal proportional to the speed by detecting the rotation of the rotating shaft (1), and the pulse signal is transmitted to the processor (13) for real-time analysis and processing after signal conditioning and analog-to-digital conversion by the acquisition board (12); the test program of the processor (13) simultaneously analyzes and processes the collected voltage signal and pulse signal, and obtains an axis trajectory diagram of the rotating shaft (1) rotating one circle and a vibration spectrum diagram of the sliding bearing-rotor system that can be displayed on the display interface, and judges whether the vibration amplitude of the rotating shaft exceeds the design safety range, whether there are abnormal frequency components, and whether the axis trajectory diverges according to the axis trajectory diagram and the vibration spectrum diagram, thereby obtaining whether the stability of the sliding bearing-rotor system under the impact load is good.

2. A sliding bearing-rotor system stability test system under impact load according to claim 1, characterized in that: The thrust bearing assembly also includes a sleeve (5-5) and a locking nut (5-6). Two thrust bearings (5-1) are mounted on the thrust bearing seat (5-4), and a thrust plate (5-2) is mounted on the inner side (i.e., mounted between the two thrust bearings 5-1). The thrust plate (5-2) is sleeved on the rotating shaft (1). The sleeve (5-5) is mounted between a thrust bearing (5-1) close to the coupling (4) and the rotating shaft (1). The locking nut (5-6) is mounted on the rotating shaft (1) close to the coupling (4). The locking nut (5-6) is axially limited by the sleeve (5-5) (the locking nut 5-6 fixes the sleeve 5-5 and the thrust plate 5-2), so that the thrust plate (5-2) rotates with the rotating shaft (1). The bearing end covers mounted on both sides of the thrust bearing seat are used to prevent foreign matter from entering the interior of the bearing.

3. A sliding bearing-rotor system stability test system under impact load according to claim 1 or 2, characterized in that: The radial bearing seat assembly includes a radial sliding bearing, a radial bearing seat, and a bearing end cover. The radial sliding bearing is fixed on the radial bearing seat. The bearing end covers are installed on both sides of the radial bearing seat to prevent foreign matter from entering the bearing. The radial bearing seat is fixed on the base plate, and the rotating shaft is installed inside the radial bearing to support its rotation.

4. A sliding bearing-rotor system stability test system under impact load according to claim 3, characterized in that: A coupling is installed at the output shaft (main shaft) of the driving motor, and the coupling is connected to the end of the rotating shaft. The wheel assembly comprises a wheel and a tension sleeve, and the tension sleeve is used to be placed inside the disc. The tension sleeve and the disc are installed on the rotating shaft by screws, and the base plate (9) is rigidly fixed on the vibration acceleration platform by bolts.

5. A sliding bearing-rotor system stability test system under impact load according to claim 3, characterized in that: The impact load applying device can select a vibration acceleration platform produced by Suzhou Weibo Testing Instrument Co., Ltd., model ATS-53 / HE0606, which is used to output different types of impact loads loaded on a sliding bearing-rotor system test bench on which the sliding bearing-rotor system is installed.

6. A method for testing the stability of a sliding bearing-rotor system under impact load, characterized in that: The object to be measured in the stability measurement method is a sliding bearing-rotor system, and the working condition is an impact load; the sliding bearing-rotor system comprises a rotating shaft (1), a plurality of wheel disc assemblies (2), each wheel disc assembly (2) comprises a wheel disc (2-1) and a tension sleeve (2-2), and each wheel disc is mounted on the rotating shaft (1) via a corresponding tension sleeve; and the method comprises the following steps: S1. Installation and configuration: The tested sliding bearing-rotor system is installed on the sliding bearing-rotor system test bench, and then the entire sliding bearing-rotor system test bench is installed on the impact load applying device, and the impact load applying device for simulating impact conditions is connected to the ground; S2. Setting the loading program: through the host computer of the impact load applying device, according to the actual working conditions or the preset load spectrum, use the interactive interface of the host computer to set the loading parameters of the impact load applying device (vibration acceleration platform): impact type, acceleration, frequency; S3, start the drive motor; start the drive motor (3) of the sliding bearing-rotor system test bench, make the shaft reach a predetermined speed, and keep stable operation, monitor the shaft speed and vibration amplitude through the test program in the monitoring and measurement system processor, and ensure that the speed fluctuates within the allowable range; S4, start the impact load applying device (vibration acceleration platform); apply the impact load to the sliding bearing-rotor system according to the loading program preset in step S2, and the control system of the impact load applying device will adjust the output of each actuator in real time to ensure that the load change meets the set requirements; S5, data acquisition: data acquisition is performed through the processor of the monitoring and measuring system. During the entire test process, the eddy current displacement sensor (10) acquires the displacement and vibration parameters of the rotating shaft (1) in real time; the photoelectric rotation speed sensor (11) acquires the rotation speed of the rotating shaft (1) in real time. The eddy current displacement sensor (10) and the photoelectric rotation speed sensor (11) synchronously record the data of multiple channels at a high sampling rate through an acquisition board to ensure the integrity and accuracy of the data; S6. Data processing: Data processing is performed through the processor of the monitoring and measurement system. The collected data is preliminarily processed using the test program: filtering and calibration; the collected data is deeply analyzed using the test program to extract characteristic values: time domain diagram, spectrum diagram, speed, axis trajectory; the data at various speeds is processed using the MATLAB script file and a report is generated to provide an intuitive and concise analysis of the stability of the sliding bearing-rotor system under impact loads; S7. Data analysis: Data analysis is performed through the processor of the monitoring and measurement system. Based on the extracted characteristic values, the stability of the sliding bearing-rotor system under impact load is evaluated. The specific evaluation indicators are whether the vibration amplitude exceeds the safety range, whether there are abnormal frequency components, and whether the axis trajectory diverges.

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