Reciprocating Compressor Motor Vibration During Initial Start-up

Abstract

Shortly after start-up of a new 4 throw 3 stage reciprocating compressor, high motor vibration was recorded on a machinery monitoring system. The single bearing motor vibration levels reached 260 microns (10.25 mils) during a run that dissipated to 25 microns (1 mil) after 20 minutes but repeated intermittently over following runs. An investigation identified several contributing factors that ultimately led to realignment of the motor and disassembly of the motor bearing seals, where damaged PTFE seals were discovered.