CN110907112A - Non-sinusoidal vibration table equipment fault diagnosis method and system - Google Patents
Non-sinusoidal vibration table equipment fault diagnosis method and system Download PDFInfo
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Abstract
The application discloses a method and a system for diagnosing equipment faults of a non-sinusoidal vibration table, wherein the method comprises the steps of obtaining preset parameters of the non-sinusoidal vibration table equipment, wherein the preset parameters comprise vibration and temperature of a motor, an electric cylinder and the vibration table and displacement of a balance position of the electric cylinder; collecting preset parameters; and analyzing the preset parameters to diagnose the fault type. The system comprises a preset parameter acquisition device, a vibration temperature sensor and a displacement sensor, wherein the preset parameter acquisition device is used for acquiring preset parameters of non-sinusoidal vibration table equipment and comprises a motor, an electric cylinder, a vibration temperature sensor arranged on the vibration table and the displacement sensor arranged on the electric cylinder; the collecting device is used for collecting preset parameters; and the analysis device is used for analyzing the preset parameters and diagnosing the fault type. The method and the system can effectively acquire and monitor the equipment fault characteristics, accurately predict the fault occurrence rate, establish a predictive maintenance mechanism, reduce the operation and maintenance cost of the equipment and improve the energy efficiency, safety and reliability of the equipment.
Description
Technical Field
The invention belongs to the technical field of casting, and particularly relates to a method and a system for diagnosing equipment faults of a non-sinusoidal vibration table.
Background
The vibration in the non-sinusoidal system vibration table equipment is that a cable is used for transmitting electric energy to replace a hydraulic pipeline for transmitting pressure energy of hydraulic oil, a digital servo electric cylinder is used for replacing a hydraulic cylinder to drive a crystallizer weighing several tons to dozens of tons to perform non-sinusoidal vibration, the control precision of the vibration table equipment is higher than that of the hydraulic cylinder by one order of magnitude, the vibration table equipment is small in installation and maintenance amount, energy-saving and environment-friendly, the surface quality of a casting blank can be obviously improved, and the vibration table equipment is widely applied to continuous casting machines such as plate blanks, square blanks, round blanks, special-shaped blanks and the like and becomes core key equipment in. The non-sinusoidal equipment is affected by the field environment and the working condition, the frequency of faults is different, the faults in the electrical aspect are basically monitored and are easy to be checked on the whole, an effective diagnosis means is lacked in the mechanical and medium aspects, wherein the mechanical loss of different degrees can occur in the motor, the screw rod and the vibration table along with the use of the equipment, and the faults of thin oil (square billet lubricating oil) and cooling gas (motor cooling gas) media can accelerate the faults of the equipment. At present, maintenance of non-sinusoidal equipment only depends on timing inspection of a field engineering department, and mainly comprises motor current inspection and screw lubrication inspection, potential faults and hidden dangers of the equipment are difficult to find in time, fault reasons are difficult to troubleshoot when the equipment fails, most of conditions are required to be returned to a factory for maintenance, and abnormal shutdown and maintenance caused by the fault cause can bring serious economic loss to a steel mill.
In particular, condition monitoring, like regular "health checks" of each machine, is usually achieved by measuring physical quantities such as vibrations and temperature, in particular vibration measuring instruments, which give a value, by comparing this measured value with a standard value, the condition of the machine can be determined. Vibration analysis is generally divided into two phases: trend monitoring and fault diagnosis, wherein the trend monitoring means that a vibration value of a certain measuring point is measured periodically and trend tracking is performed, when a trend state changes, a machine state changes and a fault occurs, and another problem is involved, when the vibration value of a certain measuring point rises, it can be determined that the machine state changes and the fault occurs, but a specific fault reason is still unknown, so that the following maintenance work has no direction, and a second level of vibration analysis needs to be entered at this time: and (5) fault diagnosis. The fault diagnosis through vibration analysis refers to the determination of the precise cause of the fault by using advanced diagnosis means equipped with a vibration measuring instrument, such as a vibration frequency spectrum, an envelope spectrum, a time domain waveform and the like. However, a single vibration monitor cannot accurately predict the failure of the vibrating equipment of the vibrating table.
Disclosure of Invention
In order to solve the problems, the invention provides a method and a system for diagnosing equipment faults of a non-sinusoidal vibration table, which can effectively acquire and monitor the equipment fault characteristics, accurately predict the fault occurrence rate, establish a predictive maintenance mechanism, reduce the operation and maintenance cost of the equipment and improve the energy efficiency, safety and reliability of the equipment.
The invention provides a fault diagnosis method for equipment of a non-sinusoidal vibration table, which comprises the following steps:
acquiring preset parameters of non-sinusoidal vibration table equipment, wherein the preset parameters comprise vibration and temperature of a motor, an electric cylinder and a vibration table, and displacement of a balance position of the electric cylinder;
collecting the preset parameters;
and analyzing the preset parameters to diagnose the fault type.
Preferably, in the method for diagnosing the equipment fault of the non-sinusoidal vibration table, the preset parameters further include the flow and quality of the thin oil, the temperature, pressure, flow and humidity of the cooling air, the temperature and humidity of the motor junction box and the temperature and humidity of the control cabinet.
Preferably, in the method for diagnosing a fault of a non-sinusoidal vibration table device, before collecting the preset parameters, the method further includes:
and performing signal conditioning on the preset parameters.
Preferably, in the method for diagnosing the equipment fault of the non-sinusoidal vibration table, the preset parameter is analyzed by a characteristic value method, a frequency spectrum analysis method or an envelope spectrum analysis method.
Preferably, in the method for diagnosing a fault of a non-sinusoidal vibration table device, after the fault type is diagnosed, the method further includes:
a fault level and fault code are displayed.
The invention provides a fault diagnosis system for equipment of a non-sinusoidal vibration table, which comprises:
the device comprises a preset parameter acquisition device, a vibration temperature sensor and a displacement sensor, wherein the preset parameter acquisition device is used for acquiring preset parameters of non-sinusoidal vibration table equipment and comprises a motor, an electric cylinder, a vibration temperature sensor arranged on the vibration table and the displacement sensor arranged on the electric cylinder;
the collecting device is used for collecting the preset parameters;
and the analysis device is used for analyzing the preset parameters and diagnosing the fault type.
Preferably, in the non-sinusoidal vibration table equipment fault diagnosis system, the preset parameter acquiring device further includes an oil flow sensor and an oil quality sensor which are arranged at the position of the thin oil outlet, a temperature and pressure sensor, a flow sensor and a temperature and humidity sensor which are arranged at the position of the cooling gas outlet, a temperature and humidity sensor which is arranged on the motor junction box, and a temperature and humidity sensor which is arranged on the control cabinet.
Preferably, in the system for diagnosing a fault of a non-sinusoidal vibration table device, the system further includes a signal conditioning device disposed between the preset parameter obtaining device and the collecting device, and configured to perform signal conditioning on the preset parameter.
Preferably, in the non-sinusoidal vibration table equipment fault diagnosis system, the analysis device is a characteristic value analysis device, a spectrum analysis device, or an envelope spectrum analysis device.
Preferably, in the above non-sinusoidal vibration table equipment fault diagnosis system, the system further comprises a fault display device connected to the analysis device, for displaying a fault level and a fault code.
According to the above description, the method for diagnosing the equipment fault of the non-sinusoidal vibration table provided by the invention comprises the steps of obtaining preset parameters of the non-sinusoidal vibration table equipment, wherein the preset parameters comprise the vibration and the temperature of the motor, the electric cylinder and the vibration table, and the displacement of the balance position of the electric cylinder; then collecting the preset parameters; and analyzing the preset parameters to diagnose the fault type, so that more preset parameters can be utilized to more fully know the equipment state, the fault type of the equipment can be better diagnosed, the fault characteristics of the equipment can be effectively collected and monitored, the fault occurrence rate can be accurately predicted, a predictive maintenance mechanism can be established, the operation and maintenance cost of the equipment can be reduced, and the energy efficiency, the safety and the reliability of the equipment can be improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is a schematic diagram of a non-sinusoidal vibration table apparatus fault diagnosis method provided herein;
FIG. 2 is an electrical layout schematic of another embodiment of a non-sinusoidal vibration table apparatus fault diagnosis method provided herein;
FIG. 3 is a schematic diagram of a non-sinusoidal vibration table equipment fault diagnosis system provided by the present application.
Detailed Description
The core of the invention is to provide a method and a system for diagnosing equipment failure of a non-sinusoidal vibration table, which can effectively collect and monitor equipment failure characteristics, accurately predict failure occurrence rate, establish a predictive maintenance mechanism, reduce operation and maintenance cost of equipment, and improve energy efficiency, safety and reliability of the equipment.
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Fig. 1 is a schematic view of an embodiment of a fault diagnosis method for non-sinusoidal vibration table equipment provided by the present application, where fig. 1 is a schematic view of the fault diagnosis method for non-sinusoidal vibration table equipment provided by the present application, and the method includes the following steps:
s1: acquiring preset parameters of non-sinusoidal vibration table equipment, wherein the preset parameters comprise vibration and temperature of a motor, an electric cylinder and a vibration table, and displacement of a balance position of the electric cylinder;
specifically, the vibration parameters may be detected by using 3 vibration sensors respectively mounted on the motor, the electric cylinder and the vibration table, and the temperature parameters may be detected by using 3 temperature sensors, and the condition of the offset of the balance position of the electric cylinder may be detected by using a displacement sensor mounted on the electric cylinder. It should be noted that, the motor needs to be provided with 1 three-axis vibration sensor for respectively monitoring the vibration information of the motor bearing in the axial direction, the vertical direction and the horizontal direction, and the vibration sensor needs to have a temperature monitoring function at the same time; 1 vibration sensor is required to be installed at a bearing above the electric cylinder to monitor the acceleration information of the reciprocating motion of the electric cylinder; the shaking table needs to be provided with 1 vibration sensor for monitoring the acceleration information of the shaking table. The vibration sensor may be a custom made imported industrial sensor with integral cable 15M (or other length) with either top or side outlet to meet specific installation conditions. The integrated cable has good waterproof and splash-proof performances, the sealing grade reaches IP67, the side outlet sensor is directly installed by using an M6 screw without moving the sensor, the top outlet sensor adopts a quick installation screw, one end of the quick installation screw is an M6 screw thread and is firstly fixed at a machine measuring point, and the other end of the quick installation screw is connected with the sensor and can be screwed down within one turn, so that the installation and maintenance are simple, and the sensor cable cannot be distorted. The installation position of the motor vibration sensor is as close to the equipment bearing to be monitored as possible, and the transmission of the vibration signal is a rigid path, so that high sensitivity to the vibration in a fault state is obtained. The vibration sensor of the electric cylinder and the vibration table is arranged on a reciprocating mechanism, the vibration sensor is fixed at a measuring point position through M6/M8 threads, and a protective cover needs to be added to the sensor at a position which is frequently touched during equipment maintenance. The displacement sensor can adopt an eddy current displacement sensor, is arranged at the electric cylinder and is used for monitoring the balance position offset condition of the electric cylinder.
S2: collecting preset parameters;
specifically, the physical quantity information transmitted by the sensor can be collected by using a data collection box, and the physical quantity information is communicated with the server through the Ethernet and the serial port.
S3: and analyzing the preset parameters to diagnose the fault type.
Specifically, the system server can be used for communicating with the non-sinusoidal PLC through Ethernet and communicating with the remote diagnosis platform in a wireless 4G mode.
As can be seen from the above description, in the embodiment of the method for diagnosing the fault of the non-sinusoidal vibration table device provided by the present application, the preset parameters of the non-sinusoidal vibration table device are obtained first, where the preset parameters include the vibration and temperature of the motor, the electric cylinder and the vibration table, and the displacement of the balance position of the electric cylinder; then collecting preset parameters; and then the preset parameters are analyzed to diagnose the fault type, so that more preset parameters can be utilized to more fully know the equipment state, the fault type of the equipment can be better diagnosed, the fault characteristics of the equipment are effectively collected and monitored, the fault occurrence rate is accurately predicted, a predictive maintenance mechanism is established, the operation and maintenance cost of the equipment is reduced, and the energy efficiency, the safety and the reliability of the equipment are improved.
In a specific embodiment of the above non-sinusoidal vibration table equipment fault diagnosis method, the preset parameters further include flow and quality of thin oil, temperature, pressure, flow and humidity of cooling air, temperature and humidity of a motor junction box, and temperature and humidity of a control cabinet.
Specifically, can utilize an fluid flow sensor of installation at lead screw thin oil entrance to monitor the circulation state of thin oil, but output switching value signal, when the thin oil flow is less than the setting value, but remote output alarm signal, replace artifical naked eye to go to observe whether the thin oil circulates. The quality of thin oil can be monitored by utilizing an oil quality sensor, the quality comprises the conditions of viscosity, particulate matters and the like, the temperature and the pressure of cooling gas are monitored by utilizing a temperature and pressure sensor arranged on a cooling gas pipeline, the flow of the cooling gas is monitored by utilizing a flow sensor arranged on the cooling gas pipeline, and the temperature and the humidity of the cooling gas, the temperature and the humidity of a motor wiring box and the temperature and the humidity of a control cabinet are respectively monitored by 3 wireless temperature and humidity sensors arranged at a motor cooling gas outlet, in the motor wiring box and in the control cabinet.
In this embodiment, the data acquisition box can comprise two parts of data acquisition and state display, wherein the data acquisition comprises the acquisition of signals such as vibration, temperature, pressure, oil, displacement, flow and the like, and the state display comprises the display of a nixie tube and a signal indicator lamp. For the vibration signal acquisition of equipment, a very high sampling frequency is required, and the sampling frequency is at least more than 2 times of the signal frequency. Taking an electric motor with a rated rotation speed of 1500r/min as an example, the rotation frequency f is 1500/60-25 HZ, and the data acquisition rate can be obtained according to an empirical formula, i.e., V is f 70-2.56-4480/s. Taking the example of 4 streams non-sinusoidal, there are 3 vibration sensors, 1 displacement sensor per stream. The motor vibration sensor needs to collect the z direction, each vibration sensor of the electric cylinder and the vibration table needs to collect the vibration value of the x, y and z axes, the electric cylinder also needs to collect displacement signals, so 8 vibration signals need to be collected at each flow, the sampling rate of the AD conversion chip needs to be more than 4480X 6X 8-215 kSPS, and in order to ensure the real-time performance and the precision of the collected data, the AD conversion chip with 8 channels, high precision and 16-bit resolution is selected. The temperature signal refers to the temperature collected by the motor, the electric cylinder and the vibration table sensor, the signal is an analog quantity voltage signal, and each flow has 3 temperature signals. The temperature and pressure signals refer to the collection of temperature and pressure signals of motor cooling air, and each flow is provided with 1 temperature and pressure sensor and collected to a 485 bus after passing through a signal conditioning module. The flow signal refers to the flow of cooling air, and 1 flow sensor is arranged in each flow, and is collected to a 485 bus after passing through the signal conditioning module. Each stream of non-sinusoidal equipment is provided with 3 wireless temperature and humidity sensors, and wireless signals are received by a wireless gateway and then transmitted to an industrial personal computer through an RS485 bus. Each flow of non-sinusoidal equipment is provided with an oil flowmeter, the output is a 24V switching value signal, and the switching value signal can be acquired through optical coupling detection. The oil quality sensor can collect the dielectric constant and temperature of thin oil, 1 oil quality sensor is arranged in every 4 streams, and the signals are collected to a 485 bus after passing through the signal conditioning module.
In another specific embodiment of the above method for diagnosing equipment failure of a non-sinusoidal vibration table, before collecting the preset parameters, the method further includes:
and performing signal conditioning on the preset parameters.
Specifically, aiming at the characteristic of multi-machine and multi-flow of the continuous casting machine, each flow needs to be provided with a non-sinusoidal device which can generate a non-sinusoidal vibration waveform, and the non-sinusoidal device has unique advantages in the aspects of controlling negative slip time and reducing the friction force of a crystallizer, can improve the surface quality of a casting blank of the continuous casting machine and prevent bonding breakout, and the more the flow number is, the more sensors are needed, and the more complicated wiring is. Due to the fact that the types and the number of the sensors are numerous, the data collecting modes of the sensors are various, and considering the system installation mode, the cost and the reliability, a signal conditioning module can be configured on each stream of non-sinusoidal equipment, only signal conditioning and operational amplification are carried out, then all signals are collected into a data collecting box, and network communication is carried out between the data collecting box and a server through a network port, and reference can be made to fig. 2, wherein fig. 2 is an electrical layout schematic diagram of another specific embodiment of the non-sinusoidal vibration table equipment fault diagnosis method provided by the application.
In another embodiment of the above method for diagnosing a fault of a non-sinusoidal vibration table apparatus, the predetermined parameter may be analyzed by a eigenvalue method, a frequency spectrum analysis method, or an envelope spectrum analysis method.
Specifically, first, characteristic values, such as a root mean square value, an average value, a peak value and the like, which can represent the running state of the equipment, are acquired, and then, according to experience or the trend situation of long-term running of the equipment, threshold value planning is performed on characteristic parameters of the equipment by using an intelligent data processing and analyzing method, so that the characteristic threshold value when the equipment fails is determined. When the alarm threshold is monitored, a fault signal needs to be preprocessed by using a wavelet decomposition technology, the fault signal is decomposed into independent frequency bands in a non-redundant, non-leakage and orthogonal mode, then the characteristic value of the fault signal is extracted according to the change of the energy proportion in the corresponding frequency band, so that the fault threshold is defined, and once the amplitude of the fault signal exceeds the alarm threshold set by the system, the system sends out an equipment fault alarm.
① root mean square analysis
The root mean square value of the signal { Xi } (i is 1 to N, and N is the number of sampling points) is
Since the root mean square value is a value averaged with time, the measured value fluctuates greatly in the case of an abnormality of a random vibration waveform such as surface wear, and an appropriate evaluation can be given. However, it is not suitable for transient shock vibration abnormalities such as surface peeling or indentation.
② Peak analysis
The peak value is the maximum value reflecting the vibration at a certain moment, and the calculation method is as follows:
let us assume that N peaks { X } have been found from N values of { Xi } by a certain peak counting methodpjJ 1 to n, the peak value of { Xi } is:
the peak value is suitable for fault diagnosis with instantaneous impact such as surface pitting damage, and is particularly easy to detect from the change of the peak value when the surface falls off in the initial stage. In addition, when the rotation speed is low (for example, below 300 r/min), the peak value is often used for diagnosis.
2) Spectrum analysis method
The frequency spectrum analysis of the vibration signal is the most widely applied method in engineering, the frequency spectrum analysis is to calculate the amplitude and phase frequency characteristic curve of the acquired data, the basic starting point is to rapidly perform Fourier transform on the acquired digital signal, so that the complex time history waveform is decomposed into a plurality of single harmonic components to be researched, and the frequency structure of the signal and the amplitude and phase information of each harmonic are obtained. The existence of the equipment fault can be presumed through spectrum analysis, but the information such as the type and the part of the fault cannot be determined. In the spectral analysis, analysis is mainly performed from 3 basic spectra of an amplitude spectrum, a power spectrum and a cepstrum.
① amplitude spectrum analysis
The amplitude frequency spectrum is obtained by performing Fourier transform (FFT) on a vibration signal obtained by processing an original signal sampled by a sensor once, calculating and drawing a frequency spectrum of the time domain vibration signal, wherein the expression of the Fourier transform is as follows:
the amplitude spectrum can represent the effective value of the harmonic frequency time domain signal, and is a linear distribution of the amplitude of each harmonic of the time domain signal along with the frequency.
② Power Spectrum analysis
The power spectrum is the situation that the distribution of the signal power is shown in the frequency domain, namely the energy of the vibration signal is shown. Its spectrum contains the same information as the amplitude spectrum, since it is the square of the amplitude and therefore more distinct than the prominent frequencies of the amplitude spectrum. The expression of the power spectrum is as follows:
③ cepstrum
The cepstrum is also called secondary spectrum. The method can effectively detect periodic components in a complex frequency spectrum, the cepstrum is usually used in mechanical vibration, and the cepstrum is more applied to vibration signal analysis in order to detect and diagnose faults.
The power cepstrum can be defined as a spectrum obtained by performing inverse fourier transform on a result of an operation after logarithmic operation on a power spectrum, that is:
Gx(t)＝F-1[logs(f)]
by cepstrum analysis, different frequency components in the signal can be identified, and periodic components important for diagnosis can be found.
3) Envelope analysis method
Envelope analysis is one of the most effective methods in fault diagnosis, and it can clearly indicate the location and severity of a fault. The envelope analysis method is mainly characterized in that a useful resonance frequency area is selected, a low-frequency envelope signal containing fault frequency is obtained through filtering, translation and transformation, and the envelope signal is subjected to time-frequency analysis, so that the fault can be diagnosed. The envelope analysis reconciles the fault-related signal from the high-frequency modulated signal, thereby avoiding confusion with other low-frequency interferences, and having high diagnostic reliability and sensitivity.
The analysis steps of the envelope analysis method are as follows: 1. comparing the power spectrums of the normal signal and the fault signal, finding out a maximum difference point as a basis for intercepting a frequency band; 2. drawing a frequency spectrum diagram of the fault signal, and carrying out filtering shift on the frequency spectrum diagram according to the frequency band intercepted by the power spectrum; 3. doubling and zero-filling the amplitude of the intercepted signal, wherein the length is doubled; 4. transforming the complex frequency domain signal to a time domain; 5. fourier transform is carried out on the time domain signal to a frequency domain; 6. and improving the frequency domain resolution and making a fine spectrum.
In a preferred embodiment of the above method for diagnosing a fault of a non-sinusoidal vibration table device, after diagnosing the fault type, the method further includes:
a fault level and fault code are displayed.
Specifically, 3 status signal lamps can be configured on the data collection box, and each status signal lamp represents a fault level of the equipment, wherein blue represents that the equipment is in an early warning state, orange represents that the equipment is in a warning state, and red represents that the equipment is in an alarm state. The data acquisition box can be also provided with 4 nixie tubes for displaying fault codes of the equipment. Each fault code corresponds to a specific fault type and fault location for the device.
Fig. 3 is a schematic diagram of a fault diagnosis system for non-sinusoidal vibration table equipment provided in the present application, where fig. 3 is a schematic diagram of a fault diagnosis system for non-sinusoidal vibration table equipment provided in the present application, and the system includes:
preset parameter acquisition device 301 for acquire the preset parameter of non-sinusoidal shaking table equipment, including setting up in the motor, vibration temperature sensor on electronic jar and the shaking table and setting up the displacement sensor on electronic jar, it is specific, can utilize 3 vibration sensors who installs respectively on motor, electronic jar and shaking table to detect the vibration parameter, and detect the temperature parameter with 3 temperature sensor, and can utilize the displacement sensor who installs on electronic jar to detect the condition of electronic jar's balanced position skew. It should be noted that, the motor needs to be provided with 1 three-axis vibration sensor for respectively monitoring the vibration information of the motor bearing in the axial direction, the vertical direction and the horizontal direction, and the vibration sensor needs to have a temperature monitoring function at the same time; 1 vibration sensor is required to be installed at a bearing above the electric cylinder to monitor the acceleration information of the reciprocating motion of the electric cylinder; the shaking table needs to be provided with 1 vibration sensor for monitoring the acceleration information of the shaking table. The vibration sensor may be a custom made imported industrial sensor with integral cable 15M (or other length) with either top or side outlet to meet specific installation conditions. The integrated cable has good waterproof and splash-proof performances, the sealing grade reaches IP67, the side outlet sensor is directly installed by using an M6 screw without moving the sensor, the top outlet sensor adopts a quick installation screw, one end of the quick installation screw is an M6 screw thread and is firstly fixed at a machine measuring point, and the other end of the quick installation screw is connected with the sensor and can be screwed down within one turn, so that the installation and maintenance are simple, and the sensor cable cannot be distorted. The installation position of the motor vibration sensor is as close to the equipment bearing to be monitored as possible, and the transmission of the vibration signal is a rigid path, so that high sensitivity to the vibration in a fault state is obtained. The vibration sensor of the electric cylinder and the vibration table is arranged on a reciprocating mechanism, the vibration sensor is fixed at a measuring point position through M6/M8 threads, and a protective cover needs to be added to the sensor at a position which is frequently touched during equipment maintenance. The displacement sensor can adopt an eddy current displacement sensor, is arranged at the electric cylinder and is used for monitoring the balance position offset condition of the electric cylinder;
the collecting device 302 is configured to collect preset parameters, specifically, a data collecting box may be used to collect physical quantity information transmitted by the sensors, and communicate with the server through an ethernet and a serial port, where the data collecting box may be a multi-channel online data collector, and an input channel is suitable for accessing various types of sensors: the device comprises a temperature vibration sensor, an acceleration sensor, an attitude sensor, a temperature pressure sensor, a circulation indicator and the like, wherein the number of the input channels of the analog quantity is 72, and the input channels of the analog quantity can be connected with analog quantity voltage signals; 10 digital input channels can connect RS485 signal, RS232 signal, switching value signal, and data acquisition box surface comprises 4 2.3 cun charactron, 3 signal indicator lamps. The indicating lamp has three colors of blue, orange and red, which respectively represent three faults of different degrees of equipment early warning, warning and alarming, 4 nixie tubes can display the fault codes of the equipment, each fault code corresponds to the fault type and the fault position of one equipment, so that field maintenance personnel can conveniently check the fault condition of the equipment, the data acquisition module can be directly connected to a system server through the Ethernet and is controlled by on-line monitoring management software, the data acquisition module acquires and processes data according to the setting conditions (time interval, rotating speed, parameter range and the like) of the system and uploads the data to a database through the on-line monitoring software, the data acquisition box can be installed at a position near a field oil tank in a welding installation mode, and all electrical signal interfaces are connected in an aviation plug mode;
the analysis device 303 is used for analyzing preset parameters and diagnosing fault types, and particularly, the system server can be used for communicating with a non-sinusoidal PLC (programmable logic controller) through an Ethernet and communicating with a remote diagnosis platform in a wireless 4G (fourth generation) mode, the system server is used for storing an online state monitoring database, factory continuous casting PLC (programmable logic controller) information and non-sinusoidal equipment state information can be collected through local area network communication, the system server is used as a core for data collection and control, can be used for controlling data collection and state display of a data collection box, and adds collected data to the database, and the industrial personal computer is used as the system server and is configured as follows: 3 gigabit network cards (scalable); 2 serial ports; 1T hard disk; 8G internal memory; a core i7 processor; the equipment state monitoring and fault diagnosis software is the core of the whole system and is used for storing data, drawing various characteristic value trends, alarming and reporting faults, summarizing a database and sharing information, and the main functions of the software are as follows: the method has the authority management function, different operation authorities of different users to the database and access authorities of different nodes can be realized through hierarchical authorization, the number of the users is unlimited, and the installation times are unlimited; the system can be compatible with various measuring instruments, has no quantity limitation, and supports online views; supporting common communication modes such as USB, Ethernet, serial ports and the like; the system can support OPC in an extensible way and can exchange data with a PLC or DCS system; support for remote diagnostic services; the data backup and recovery function is provided; establishing basic information and measuring point parameter information of the equipment step by adopting a multi-level tree structure, and adding or modifying additional information of the equipment, such as equipment description, equipment photos, centering reports and the like; the system has complete signal processing and analyzing functions, including time domain analysis, frequency spectrum, phase, impulse, envelope spectrum, cepstrum, three-dimensional frequency spectrum, axis locus, Bode diagram, trend analysis, sideband analysis and the like; the three-dimensional display function is realized, and the three-dimensional vibration track curve and the inclination direction of the vibration table can be displayed; reports are exported in a common format; various reports and reports can be generated according to the requirements, the reports have built-in templates and also support custom report formats; a built-in hundreds of thousands of bearing databases, comprising: SKF, FAG, NSK, NTN, DODGE, COO, FAGNIR, GMN, INA, MES, MRC, NDH, RHP, SEA, TIM, KEN, TORRING, etc. and various commonly used international vibration standards, such as ISO10836, etc. and includes various gear box, pulley, etc. organization databases, while supporting user-defined; various alarm modes can be set, such as amplitude alarm, frequency band alarm, side band alarm and the like, and the alarm standard can refer to a built-in international standard and is also customized by a user; the full Chinese operation interface has a perfect help system; and the user is supported to customize various sensors.
In an embodiment of the above non-sinusoidal vibration table equipment fault diagnosis system, the preset parameter acquiring device further includes an oil flow sensor and an oil quality sensor which are disposed at a position of the thin oil outlet, a temperature and pressure sensor, a flow sensor and a temperature and humidity sensor which are disposed at a position of the cooling gas outlet, a temperature and humidity sensor which is disposed on the motor junction box, and a temperature and humidity sensor which is disposed on the control cabinet. Specifically, can utilize an fluid flow sensor of installation at lead screw thin oil entrance to monitor the circulation state of thin oil, but output switching value signal, when the thin oil flow is less than the setting value, but remote output alarm signal, replace artifical naked eye to go to observe whether the thin oil circulates. The quality of thin oil can be monitored by utilizing an oil quality sensor, the quality comprises the conditions of viscosity, particulate matters and the like, the temperature and the pressure of cooling gas are monitored by utilizing a temperature and pressure sensor arranged on a cooling gas pipeline, the flow of the cooling gas is monitored by utilizing a flow sensor arranged on the cooling gas pipeline, and the temperature and the humidity of the cooling gas, the temperature and the humidity of a motor wiring box and the temperature and the humidity of a control cabinet are respectively monitored by 3 wireless temperature and humidity sensors arranged at a motor cooling gas outlet, in the motor wiring box and in the control cabinet.
In this embodiment, the data acquisition box can comprise two parts of data acquisition and state display, wherein the data acquisition comprises the acquisition of signals such as vibration, temperature, pressure, oil, displacement, flow and the like, and the state display comprises the display of a nixie tube and a signal indicator lamp. For the vibration signal acquisition of equipment, a very high sampling frequency is required, and the sampling frequency is at least more than 2 times of the signal frequency. Taking an electric motor with a rated rotation speed of 1500r/min as an example, the rotation frequency f is 1500/60-25 HZ, and the data acquisition rate can be obtained according to an empirical formula, i.e., V is f 70-2.56-4480/s. Taking the example of 4 streams non-sinusoidal, there are 3 vibration sensors, 1 displacement sensor per stream. The motor vibration sensor needs to collect the z direction, each vibration sensor of the electric cylinder and the vibration table needs to collect the vibration value of the x, y and z axes, the electric cylinder also needs to collect displacement signals, so 8 vibration signals need to be collected at each flow, the sampling rate of the AD conversion chip needs to be more than 4480X 6X 8-215 kSPS, and in order to ensure the real-time performance and the precision of the collected data, the AD conversion chip with 8 channels, high precision and 16-bit resolution is selected. The temperature signal refers to the temperature collected by the motor, the electric cylinder and the vibration table sensor, the signal is an analog quantity voltage signal, and each flow has 3 temperature signals. The temperature and pressure signals refer to the collection of temperature and pressure signals of motor cooling air, and each flow is provided with 1 temperature and pressure sensor and collected to a 485 bus after passing through a signal conditioning module. The flow signal refers to the flow of cooling air, and 1 flow sensor is arranged in each flow, and is collected to a 485 bus after passing through the signal conditioning module. Each stream of non-sinusoidal equipment is provided with 3 wireless temperature and humidity sensors, and wireless signals are received by a wireless gateway and then transmitted to an industrial personal computer through an RS485 bus. Each flow of non-sinusoidal equipment is provided with an oil flowmeter, the output is a 24V switching value signal, and the switching value signal can be acquired through optical coupling detection. The oil quality sensor can collect the dielectric constant and temperature of thin oil, 1 oil quality sensor is arranged in every 4 streams, and the signals are collected to a 485 bus after passing through the signal conditioning module.
The parameters of the vibration sensor described above may be as follows: acceleration range: 5 +/-g; temperature range: -50 to 200 ℃; working temperature: -30 to 80 ℃; frequency response: 0.1-1000 HZ; vibration sensitivity: 1000 mv/g; size: 56 × 52 × 25 mm. The displacement sensor indirectly measures distance parameters between a tested piece and the sensor in an eddy current induction mode as follows: measuring range: 10 mm-30 mm; precision: 2 percent; sensitivity: 0.3V/mm (304 stainless steel coupons); working temperature: 0 to 80 ℃. The temperature and pressure integrated sensor takes a high-quality diffused silicon pressure sensor as a main measuring element, carries a leading digital processing circuit board in the world, and can simultaneously measure the medium pressure and temperature at the same point, and the measuring range is as follows: 0-5Mpa and-40-85 ℃; working temperature: -40 to 125 ℃; precision: 0.25 percent; overload pressure: 1.5 times of full range; protection grade: IP 65; outputting a signal: and RS 485. The flow sensor can select a vortex street flowmeter, adopts the induction principle of eddy current to detect the flow of gas, and has the main technical parameters: measuring range: 4-28 m 3/h; temperature of the medium: -40 ℃ to 350 ℃; pressure of the medium: 0-1.6 Mpa; outputting a signal: and RS 485. The lead screw is lubricated through the thin oil, and the flow of thin oil can be monitored to the fluid sensor for judge the circulation condition of thin oil, and the fluid sensor is installed at the lead screw oil inlet, installs on the oil inlet pipeline through the clamp. The oil quality sensor is used for detecting the dielectric constant and the temperature of oil, the dielectric constant can comprehensively reflect the performance of lubricating oil, reflect the change of the comprehensive physicochemical indexes of the oil caused by factors such as water inlet, acidification, oxidation, additive failure, wear particles and the like, and judge whether the oil can be continuously used, and the main technical parameters are as follows: working temperature: -40 to 85 ℃; dielectric constant: 1-10: pt 1000; the dielectric constant precision is +/-0.01; protection grade: IP 67. Temperature and humidity sensor adopts wireless communication's mode, the temperature and the humidity of measurable quantity environment, main technical parameter: working temperature: -20 to 80 ℃; transmission distance: the open distance is 800 meters.
The system can utilize more preset parameters to more fully know the equipment state, so that the fault type of the equipment can be better diagnosed, the fault characteristics of the equipment can be effectively collected and monitored, the fault occurrence rate can be accurately predicted, a predictive maintenance mechanism can be established, the operation and maintenance cost of the equipment can be reduced, and the energy efficiency, safety and reliability of the equipment can be improved.
In another specific embodiment of the above non-sinusoidal vibration table equipment fault diagnosis system, the system further includes a signal conditioning device disposed between the preset parameter acquiring device and the collecting device, and configured to perform signal conditioning on the preset parameter. The signal conditioning device can be used for conditioning, amplifying and summarizing signals of each sensor, comprises an analog quantity operational amplifier circuit with 11 channels, can enhance the signal anti-interference capability, and can be mounted on a motor shell. Specifically, aiming at the characteristic of multi-machine and multi-flow of the continuous casting machine, each flow needs to be provided with a non-sinusoidal device which can generate a non-sinusoidal vibration waveform, and the non-sinusoidal device has unique advantages in the aspects of controlling negative slip time and reducing the friction force of a crystallizer, can improve the surface quality of a casting blank of the continuous casting machine and prevent bonding breakout, and the more the flow number is, the more sensors are needed, and the more complicated wiring is. Because the variety and the quantity of sensor are numerous, the data mode of gathering the sensor has a variety of, from system installation mode, cost and reliability three sides consideration, can join in marriage a signal conditioning module at every stream non-sinusoidal equipment, only carry out the conditioning and the fortune of signal and put, then in gathering a data acquisition box with all signals, then carry out network communication through net gape and server.
In another specific embodiment of the above non-sinusoidal vibration table equipment fault diagnosis system, the analyzing device is a characteristic value analyzing device, a spectrum analyzing device or an envelope spectrum analyzing device. Specifically, first, characteristic values, such as a root mean square value, an average value, a peak value and the like, which can represent the running state of the equipment, are acquired, and then, according to experience or the trend situation of long-term running of the equipment, threshold value planning is performed on characteristic parameters of the equipment by using an intelligent data processing and analyzing method, so that the characteristic threshold value when the equipment fails is determined. When the alarm threshold is monitored, a fault signal needs to be preprocessed by using a wavelet decomposition technology, the fault signal is decomposed into independent frequency bands in a non-redundant, non-leakage and orthogonal mode, then the characteristic value of the fault signal is extracted according to the change of the energy proportion in the corresponding frequency band, so that the fault threshold is defined, and once the amplitude of the fault signal exceeds the alarm threshold set by the system, the system sends out an equipment fault alarm.
In a preferred embodiment of the above-mentioned fault diagnosis system for non-sinusoidal vibration table equipment, the system further comprises a fault display device connected with the analysis device for displaying fault grade and fault code.
Specifically, 3 status signal lamps can be configured on the data collection box, and each status signal lamp represents a fault level of the equipment, wherein blue represents that the equipment is in an early warning state, orange represents that the equipment is in a warning state, and red represents that the equipment is in an alarm state. The data acquisition box can be also provided with 4 nixie tubes for displaying fault codes of the equipment. Each fault code corresponds to a specific fault type and fault location for the device.
The faults that can be detected using the method and system provided by the above embodiments are shown in table 1:
TABLE 1 Equipment State Fault Table
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended 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 (10)
1. A fault diagnosis method for equipment of a non-sinusoidal vibration table is characterized by comprising the following steps:
acquiring preset parameters of non-sinusoidal vibration table equipment, wherein the preset parameters comprise vibration and temperature of a motor, an electric cylinder and a vibration table, and displacement of a balance position of the electric cylinder;
collecting the preset parameters;
and analyzing the preset parameters to diagnose the fault type.
2. The non-sinusoidal vibration table equipment fault diagnosis method according to claim 1, wherein the preset parameters further include flow and quality of thin oil, temperature, pressure, flow and humidity of cooling air, temperature and humidity of motor junction box, and temperature and humidity of control cabinet.
3. The non-sinusoidal vibration table apparatus fault diagnosis method according to claim 1, further comprising, prior to said collecting said preset parameters:
and performing signal conditioning on the preset parameters.
4. The non-sinusoidal vibration table apparatus fault diagnosis method according to claim 1, wherein the preset parameters are analyzed using eigenvalue, frequency or envelope spectrum analysis.
5. The non-sinusoidal vibration table equipment fault diagnosis method according to any one of claims 1-4, further comprising, after diagnosing the type of fault:
a fault level and fault code are displayed.
6. A non-sinusoidal vibration table equipment fault diagnostic system, comprising:
the device comprises a preset parameter acquisition device, a vibration temperature sensor and a displacement sensor, wherein the preset parameter acquisition device is used for acquiring preset parameters of non-sinusoidal vibration table equipment and comprises a motor, an electric cylinder, a vibration temperature sensor arranged on the vibration table and the displacement sensor arranged on the electric cylinder;
the collecting device is used for collecting the preset parameters;
and the analysis device is used for analyzing the preset parameters and diagnosing the fault type.
7. The non-sinusoidal vibration table equipment fault diagnosis system according to claim 6, wherein the preset parameter acquiring device further includes an oil flow sensor and an oil quality sensor disposed at a thin oil outlet, a temperature and pressure sensor, a flow sensor and a temperature and humidity sensor disposed at a cooling gas outlet, a temperature and humidity sensor disposed on a motor junction box, and a temperature and humidity sensor disposed on a control cabinet.
8. The system according to claim 6, further comprising a signal conditioning device disposed between the predetermined parameter acquiring device and the collecting device for signal conditioning the predetermined parameter.
9. The non-sinusoidal vibration table equipment fault diagnosis system according to claim 6, wherein the analysis means is eigenvalue analysis means, frequency spectrum analysis means or envelope spectrum analysis means.
10. The non-sinusoidal vibration table equipment fault diagnosis system according to any one of claims 6-9, further comprising fault display means connected to said analysis means for displaying fault levels and fault codes.
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