Rotating Machinery Reliability
Vibration Trend, Frequency Spectrum and time Waveform.
Generator Journal Orbit Indicated High Preload (Flattening of Orbit) Due to Seal Rub..
The vibration of machines and structures can be measured at discrete points on the machine and shafts. Typically accelerometers or velocity sensors and a spectrum analyzer are used to measure housing and structural vibration during trouble shooting or periodically (30 days is typical). Non-contact eddy current proximity probe are used to measure shaft relative motion to the bearing housing. The vibration data can be displayed in the frequency or time domain.
Various components of machinery generate frequencies of vibration in normal operation and also as the components wear or develop defects. The frequencies generated by bearings, gears, sheaves, belts, pump and compressor impellers, etc., can be calculated. These frequencies can provide indications of defects or wear of components. Trending of the vibration is a very powerful tool for detecting subtle changes in the machine's health.
High frequency vibration data analysis using PeakVue (Patented by CSI) can provide early detection of rolling element bearing or gear defects. It is an excellent technology for slow speed bearing analysis.
Data from non-contact proximity probes can be used to evaluate journal motion in the bearings as well as provide information about oil film development and the journal's position in the bearing clearance.