Method to Calculate Turbine Generator Unit Bearing Load Distribution Using Journal Raising Rate

A new bearing load distribution calculation method using the measured journal raising rate on the base of transfer matrix theory is presented. Shaft is divided into several sections at bearings. Journal raising rate difference at two ends of shaft section is decided by moments, shear forces, mass distribution along the section and bearing loads. Moment and shear force at left side of the first bearing can be calculated directly by using force and moment equilibrium equations. The first bearing load can be calculated from these two values and the measured journal raising rate at two bearings. Moment and shear force at left side of the second bearing can be calculated thereafter in the same way. The method is extended to later sections one by one until total bearing loads are calculated. The method is compared and verified with that of jack up method on test rig. It is used for bearing load identification and alignment analysis of a large turbine generator unit successfully. The method is a unitary identification method for shaft alignment analysis without taking off coupling bolts.