The maintenance of the hottest paper machine also

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Paper machine maintenance should also be transformed and upgraded

with the development of science and technology, the structure of paper machine is constantly optimized. The traditional inspection methods of paper machine equipment (mainly listening stick inspection) and the method of judging equipment faults based on experience can no longer meet the maintenance requirements of modern paper machine. Especially after the emergence of the paper machine with an annual output of 200000 tons, or even 400000 or 800000 tons, the paper machine equipment maintenance personnel have further improved the judgment requirements for the accuracy of equipment failure, and the equipment fault diagnosis technology just meets this demand. One of its major advantages is that it can make accurate judgments on equipment faults, and can be used as a basis to optimize the formulation of equipment maintenance and repair strategies

due to its own characteristics, the mechanical structure will inevitably produce vibration in the process of operation. When the operating conditions of the equipment do not change, its vibration will remain at a relatively stable level. When the equipment breaks down, such as bearing damage, gear collapse, dynamic imbalance, etc., its vibration condition will inevitably change, said Zhen Ronghui. If the vibration source that changes the vibration condition of the equipment can be found and analyzed, the cause of equipment failure can be determined

but in the actual vibration data measurement of the percentage of the ratio of the work recovered during the contraction of the sample to the work consumed during the extension, the vibration 14 collected by the sensor realizes the independent operation of the host computer and the microcomputer; Dynamic signal (time domain signal of vibration) is the comprehensive embodiment of equipment vibration. It includes not only the vibration signal generated by the normal operation of the equipment, but also the vibration signal generated by the equipment failure, as well as other interference signals such as noise. If the collected vibration signal is directly analyzed, it will be difficult to determine the fault source, which will affect the accuracy of fault judgment plus medium and long-term slurry price support. Fourier transform transforms complex time-domain signal analysis into simple frequency-domain signal analysis. Through the analysis of the failure frequency, the failure cause of the equipment can be determined, so that targeted maintenance and repair strategies can be adopted for the failed equipment

application of equipment fault diagnosis technology

equipment inspectors found abnormal vibration of the second press ZL roll gearbox in the press department during routine inspection. Due to the complex structure of the equipment, the inspectors could not determine the specific cause of the abnormal vibration. In order to determine the vibration cause of ZL roll, the vibration data of gearbox is collected. Through the analysis of the spectrum, the vibration with the frequency of 97.55hz is abnormal, and multiple harmonics based on this frequency also appear (Fig. 2)

calculate the failure frequency of each type of bearing through the bearing model. See Table 1 for specific data. According to the data comparison in Table 1, the fault frequency in the spectrum diagram is caused by the inner ring fault of bearing 1 in the gearbox. The vibration caused by the inner ring fault also excited 6% of the inner ring fault frequency × Frequency doubling indicates that the fault of bearing inner race has been very serious. According to the diagnosis results, the workshop timely arranged the shutdown of the paper machine and conducted targeted maintenance on the gearbox. It was found that the inner ring of bearing 1 (the bearing on the inner side) was seriously damaged (Fig. 3), which was consistent with the diagnostic result. The reason for the damage is that the lubricating oil pipe of the bearing in the gearbox is blocked, resulting in the lack of oil and damage of the bearing

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