[0036] The present invention will be described in detail below in conjunction with the drawings.
[0037] Such as figure 1 Shown, a comprehensive use of acoustic emission signal analysis, wireless temperature measurement analysis and oil analysis for 2000m 3 The process of the fault diagnosis method of the blast furnace bell-free top gearbox is: respectively use acoustic emission detection technology, wireless temperature measurement technology and oil detection technology on the blast furnace top gearbox, and then integrate the results of the three to perform the final fault diagnosis.
[0038] Such as figure 2 As shown, there are four main steps in acoustic emission signal analysis:
[0039] 1) image 3 It is a schematic diagram of the blast furnace top gear box structure, B1-E20 are the gear marks on the blast furnace transmission system. Figure 4 It is a schematic diagram of acoustic emission sensor installation. Acoustic emission measurement points are selected at the input and output ends of the rotating motor of the upper gearbox, and a total of 6 measurement points in the horizontal and vertical directions of the large gearbox housing, marked A1-A6 in the figure, to detect the acoustic signal of crack propagation. Monitor the running status of the bearings and gears of the upper gearbox, the connecting shaft of the lower gearbox, and the bearings and gears inside the gearbox. The installation method of the sensor is to polish the contact surface with the sensor smoothly at the selected measuring point position, and then apply high-temperature vacuum grease to make the acoustic emission sensor base directly contact the surface of the measured object. The sensor is fixed by a high-strength magnetic base.
[0040] The acoustic emission signal collected by the acoustic emission sensor in real time is transmitted to the data collector via a cable for amplification, A/D conversion and deep filtering, and then uploaded to the computer.
[0041] 2) Perform adaptive morphological filtering on the signal. Initialize structural elements. Select the linear structure element, the initial length is 2. Set the length interval of the structural element. The length of the structural element should be less than the period of the corresponding shock pulse signal when the bearing outer ring, bearing inner ring, bearing rolling element, gear and other faults occur. The closed operation is used as the morphological operator to perform the closed operation on all the structural elements of the length in the set interval, and calculate the energy ratio SNER between the noise reduction result after each filtering and the original signal. The calculation formula of energy ratio is as follows:
[0042] SNER = 10 log 10 ( E x E s )
[0043] Where E x Is the signal energy after noise reduction, E s Is the filtered noise signal.
[0044] In the process of structuring elements, the signal energy ratio SNER value changes as the structure length increases, and the structure element with the largest SNER value is selected to filter the signal.
[0045] 3) Perform wavelet noise reduction processing on the filtered signal. Select the most commonly used db wavelet base, sym wavelet base, coif wavelet base, and dmey wavelet base to decompose the band-pass filtered signal in three to five layers respectively, and select three threshold functions and heursure thresholds: hard threshold, soft threshold, and compromise threshold Threshold quantization is performed on the decomposed high-frequency detail signal, and then wavelet reconstruction is performed. Due to the different choices of wavelet basis, decomposition level, threshold function and threshold value, a total of 36 wavelet noise reduction results can be obtained in this way. In order to select the result with the best noise reduction effect, the signal-to-noise ratio is used as the measurement standard, and the group with the largest signal-to-noise ratio is selected as the final noise reduction result. The calculation formula of SNR is as follows:
[0046] SNR = 10 log ( X n = 1 N x 2 ( n ) X n = 1 N [ x ^ ( n ) - x ( n ) ] 2 )
[0047] In the formula, x(n) is the bandpass filtered signal, Is the signal after wavelet denoising, and N is the number of sampling points.
[0048] 4) Perform Hilbert demodulation analysis on the signal after wavelet denoising. Determine whether there are obvious fundamental frequency and frequency multiplication components of the fault characteristic frequency. If it does not exist, continue to collect the acoustic emission signal in real time and analyze it again according to the above process. If it exists, it is preliminarily judged that the blast furnace top gearbox is malfunctioning. Compare the fundamental frequency with the characteristic frequency of each fault of the bearing and gear. When the fundamental frequency is close to the characteristic frequency of a certain fault, the location of the fault can be further judged.
[0049] Such as Figure 5 As shown, temperature analysis has two main steps:
[0050] 1) Design a wireless temperature measurement system applied to the top gearbox of a blast furnace, which mainly includes five parts: wireless temperature measurement acquisition device, wireless temperature measurement transmission device, wireless routing relay station, wireless central receiving station, and data acquisition software.
[0051] The first part, the wireless temperature measurement and acquisition device 1 is a temperature sensor, which is welded and installed on the outer end surface of the gear of the lower gear box E19. Its technical parameters are: working power supply, DC3.6V lithium battery (3600mA/h); transmitting power, 80mW; working frequency band, 2.4GHz; wireless transmission rate, 250kbps; measurement range, -10~100℃; transmission distance, 150~ 500m; the sensor installation position is as Image 6 As shown, the installation position is very different from the traditional method. It is no longer installed on the equipment housing or base for indirect measurement, but directly placed a temperature acquisition device at the measured component of the mobile machinery to make the measurement result more accurate. Accurate and more reliable.
[0052] The second part, wireless temperature measurement and transmission device 2, is mainly used for wireless data transmission in the system. Its technical parameters are: working power supply, DC3.6V lithium battery (7200mA/h); transmitting power: 80mW; working frequency band, 2.4 GHz; wireless transmission rate, 250kbps; measurement range, -10~100℃; transmission distance, 150~1000m (up to 40 kilometers for special applications), placed adjacent to the wireless temperature measurement collection device.
[0053] The third part, the wireless router relay station 3 is a wireless router forwarding device, which has the function of signal transmission "relay". It is the main equipment of the wireless network, and its technical parameters are: working power supply, AC220V; working frequency band, 2.4GHz; modulation method, direct sequence spread spectrum; transmitting power 80mW; transmitting distance: 100~1000m.
[0054] The fourth part, the wireless central receiving station is a wireless receiving device, it will receive the data signal into the computer network system through a wired connection, usually installed in the computer room. Its technical parameters are: working power supply, AC220V; baud rate, 9600, 38400bps; working frequency band, 2.4GHz; data interface, RS-232 (with serial cable, can be directly connected to the computer COM port).
[0055] The fifth part is the data acquisition software, which drives the A/D card to complete the digital conversion of industrial signals (temperature signals), automatically saves and classifies the signals in a regular manner for analysis, and prompts over-standard industrial signals, and the number and period of data storage It can be controlled by software, realizing real-time monitoring and analysis of temperature information.
[0056] 2) Perform trend analysis on the measured temperature data. According to the design requirements of the blast furnace roof gearbox, the temperature inside the box during normal operation is required to be less than 70 degrees Celsius. If it is higher than 70 degrees Celsius for a long time, it will cause grease lubrication failure and cause direct friction and damage to the components. The most important factors affecting the fluctuation of the temperature measured by the system are gear engagement, wear, and the sealing effect of the airtight box. If the gear teeth are in a fault condition for a long time due to poor lubrication or bite, the increase in friction will cause the temperature of the gear teeth to rise, and the abnormality can be learned in time from the data measured by the wireless temperature measurement signal; if Problems with the sealing of the airtight box or problems with nitrogen pressure and flow can also cause a rapid increase in the ambient temperature. In the normal state of the gearbox on the top of the blast furnace, after a period of time to collect and organize the wireless temperature measurement signal data, the temperature range is basically maintained within the range of 35 degrees Celsius to 55 degrees Celsius. In the trend analysis, if the temperature basically remains below 55 degrees Celsius, continue to monitor the temperature signal in real time. If the temperature is higher than 55 degrees Celsius for a long time, it is judged that the blast furnace top gear box is malfunctioning.
[0057] Such as Figure 7 As shown, there are three main steps in oil analysis:
[0058] 1) Use professional sampling tools to extract oil. The sampling interval is adjusted according to the actual operating status of the equipment. Shorten the sampling time interval when the equipment is in the running-in period, the sound emission signal and the temperature signal are comprehensively analyzed to find the hidden troubles, and the equipment is close to the maintenance period; the sampling period can be extended during the normal operation of the equipment.
[0059] 2) Perform routine physical and chemical index detection on the extracted oil sample. Select viscosity, moisture, impurity particles, acid value, oxidation and flash point as analysis indicators to determine the degree of deterioration of the oil (grease). Compare the test result with the set value. When the result exceeds the set value, it is judged that the lubricating performance of the oil (grease) has decreased, and the spectrum and ferrograph analysis are continued; otherwise, the lubricating performance is good, and the oil sample is taken again according to the sampling cycle.
[0060] 3) Apply spectroscopy and ferrograph analysis techniques to qualitatively and quantitatively detect the extracted oil samples. Compare the composition and content of metal wear in the detected oil sample with the set value. When the content of any component in the metal abrasion in the oil sample exceeds the set value, it is judged that there is no hidden trouble, and the oil sample is taken again according to the sampling cycle; when the content of any component in the metal abrasion in the oil sample exceeds the set value Set the value and determine that there is a hidden danger of failure.
[0061] Such as figure 1 As shown, oil detection technology, acoustic emission detection technology and wireless temperature measurement technology are at 2000m 3 There are three main steps in the comprehensive application of the fault diagnosis of the blast furnace bellless top gearbox:
[0062] 1) Through regular blast furnace top gear box oil detection, routine physical and chemical index detection, spectroscopy and ferrograph analysis of the extracted oil samples, analysis of equipment lubrication and wear status, prediction of equipment failure, and determination of equipment failure location, type and cause . If the conclusion is that there is a hidden danger of failure, it is determined that the blast furnace top gearbox has a failure, a fault diagnosis report is written, and maintenance suggestions are made to the factory.
[0063] 2) Oil detection can well identify early failures of intermittent low-speed and heavy-duty equipment, but due to the difficulty of sampling the oil in the blast furnace roof gear box, it cannot be monitored in real time. Acoustic emission detection technology and wireless temperature detection technology are used for real-time monitoring to assist oil detection to comprehensively analyze the operating status of the blast furnace top gearbox. If both acoustic emission signal analysis and temperature analysis determine that there is a hidden trouble, it is determined that the blast furnace top gearbox is faulty, a fault diagnosis report is written, and maintenance suggestions are made to the factory.
[0064] 3) If the results of acoustic emission signal analysis and temperature analysis are not the same, in order to prevent misjudgment or failures caused by non-mechanical problems such as sealing, the established oil sampling period should be shortened, and the oil analysis should be carried out immediately and the analysis results should be obtained. If the oil analysis concludes that there is no hidden trouble, the operating status of the gearbox on the top of the blast furnace should be closely monitored in the near future and comprehensive analysis should be conducted again. If the conclusion is that there is a hidden danger of failure, it is determined that the blast furnace top gear box has a failure, a fault diagnosis report is written, and maintenance suggestions are made to the factory.
