Abstract: The 4M150 reciprocating compressor, as China's first domestically developed model with the maximum piston force (1,500 kN), has filled the technological gap in large-thrust reciprocating compressors in China. With the accumulation of installed units and operating hours, frequent detachment of the Babbitt metal layer on the main bearing bushes has occurred in multiple compressors, severely compromising the normal operation of the equipment. Through systematic analysis, it has been confirmed that coaxiality deviation in the bearing bore is the primary cause of localized overload and subsequent Babbitt alloy detachment. After adopting specially designed eccentric bearing bushes, the equipment has operated continuously for over 8,000 hours without recurrence of similar failures, verifying the effectiveness of the solution. According to incomplete statistics, similar problems have occurred in models like 4M125 since 2017 and were resolved using the same solution. However, as late as 2021, most failure cases still repeatedly went through the cycle of "analysisbearing replacementreoccurrence of failure" (averaging 2.3 bearing replacements per case), exposing gaps in the industry-wide knowledge transfer and sharing mechanism. This paper further discusses the fundamental causes of bearing bush failures and proposes improvement suggestions.

Key words: 4M150, reciprocating compressor, Babbitt metal, aluminum-magnesium alloy, bearing failure