After the analyses of the malfunction of the #5 turbine's rear shaft bearing in ShenZhen Yueliangwan Powerplant (Moon Bay)
the bad shape oil-film wedge caused by scraping the shaft bushing in overhaul and the impurity in the lubricating oil are regarded as the main reason of the shaft bushing's abrasion in low rotate speed. Increasing the lubricating oil's pureness and adoption the correct scrapingbushing technique can avoid the malfunction of the shaft bearing.