Full Scale Dynamic Propulsion Shaft Alignment Investigation

Abstract

SKF Marine ISC was requested by STX Finland Oy, location Rauma to perform full scale dynamic propulsion shaft measurements on board of the RoPax vessel “Pride of France” in order to solve high shaft support bearing operational temperatures. After modeling the propulsion line with a state-of-the-art CAE software for shaft alignment and vibration calculations and recording of the actual static bearing load and actual static bending stress of the accessible shaft line, during a sea trial, several dynamic measurements like dynamic bending stress, shaft torque and speed, shaft orbit, bearing temperature, vibration and longitudinal shaft movement were measured and recorded. After analysis of the measured and recorded data, following conclusions could be made; Large longitudinal shafts movements were present in operational condition. Measured shaft support bearing temperatures have a linear relationship with measured and calculated bearing load in operational condition, so temperature readings can be used as a condition monitoring tool to calculate bearing load in different operational conditions.