Steam Turbine with 0.9X Vibrations

Abstract

This 15 MW steam turbine/gearbox/4-pole generator train, following a recent overhaul, was showing unusual phenomenon of high level 0.9X vibration during shutdown, as well as power limits due to vibration level increase. The case describes a single day* field investigation program, that lead to identification of the root cause of the problem and pin pointed other problems with the quality of the overhaul. Vibration data are reviewed showing solution through application of standard** methodology