Gear Box Bull Gear High Vibration due to Fluid Instability and Analytical Evaluation of New Bearing Design

Case StudiesThree shaft Gear Box upgraded to meet Screw compressor model upgrade. Gear Box was installed, as a part of compressor upgrade project, with Bentley Nevada 3500 Shaft vibration protection facility and observed trip on commissioning. Detail analysis of shaft vibration plots clearly indicated sub-synchronous vibration component as source of machine trip which is attributed due to Fluid instability inside the bearing. The case study represents gear box shaft high vibration detail analysis and proposed Bearing Modification for resolution