Journal Bearing Wear Monitoring via On-Line Visual Ferrography

摘要

Wear condition of journal bearing was experimentally monitored with an On-Line VisualFerrograph (OLVF) system.The round bearing was made of 45# steel with babbitt alloy bushing andthe bearing journal was made of 45# steel.High stress of the water content of 0%,1%,3% in lubricant,10 times of a normal load of 2200 N,and the rotating speeds at 500,1000,2000 rpm were adopted inaccelerated experiment.A quantitative index of particle coverage area (IPCA) together with weardebris ferro-image was used to characterize wear degree and wear mechanisms.Three wear stageswith corresponding wear debris ferro-images were identified from IPCA variations characterized bybathtub curve trend.The first one was running-in stage characterized by the highest wear debrisproducing rate and higher large debris content.The second one was normal wear stage characterizedby the lowest wear debris producing rate and small normal debris.The final one was failure initiationstage characterized by higher wear debris producing rate and higher large debris content.Thecorresponding dominant wear mechanisms were micro-ploughing and micro–cutting induced byrough initial surfaces in the running-in stage,local rub due to vibration in the normal stage,andfatigue and abrasive wear in the failure initiation stage.