Turbine shaft balancing

摘要

A multi-shaft gas turbine has an inner shaft rotatably supported at opposite ends thereof with one end adapted to be connected to a load and the other end to a turbine wheel with a tubular section that receives a balance tube removably mounted within the shaft and accessible from the aft end of the engine by removal of an inner exhaust cone and a bearing pump cover. The balance tube includes front, rear and intermediate circumferentially arranged splined lands that bear balance weights angularly positioned on the tube prior to insertion thereof into the shaft, each of the weights having a peripheral surface thereon for locating the longitudinal axis of the balance tube colinearly of the longitudinal axis of the inner shaft.