초록 ▼

From the viewpoint of the preventive maintenance operation of a rotary machine, it is a very important subject to monitor the shaft vibration of the rotary machine and grasp the operating state of the machine. This invention relates to input processings in the case of executing the frequency analysi

From the viewpoint of the preventive maintenance operation of a rotary machine, it is a very important subject to monitor the shaft vibration of the rotary machine and grasp the operating state of the machine. This invention relates to input processings in the case of executing the frequency analysis of a shaft vibration signal by digital processings. This invention describes the rotational frequency synchronization of a sampling frequency, the phase synchronization of the rotary machine to a reference phase, the relationship between an analytical wave number and a sample nunber, etc. in that case.

대표청구항 ▼

A method of monitoring a shaft vibration of a rotary machine comprising the steps of: detecting the shaft vibration as a wave signal in proportion to a rotational frequency of the rotary machine; filtering the detected shaft vibration signal; sampling the filtered signal at a predetermined frequency

A method of monitoring a shaft vibration of a rotary machine comprising the steps of: detecting the shaft vibration as a wave signal in proportion to a rotational frequency of the rotary machine; filtering the detected shaft vibration signal; sampling the filtered signal at a predetermined frequency, the predetermined frequency being selected by; (a) selecting the number of waves of the filtered signal to be included in an analyzing time interval determined by at least a minimum fractional harmonic of the rotational frequency which exists in a frequency range to be monitored, (b) selecting the number of samples to be sampled from the filtered signal in the analyzing time interval in accordance with a ratio of a maximum higher harmonic of the rotational frequency to the minimum fractional harmonic of the rotational frequency in the frequency range to be monitored, and (c) multiplying the rotational frequency by a ratio of the selected number of samples to the selected number of waves with the product thereof being the predetermined frequency; and analyzing the sampled data to obtain the vibration amplitude of frequency components within the frequency range to be monitored by digital processing so as to monitor the shaft of vibration state of the rotary machine.