Tilting Pad Bearing Design.

Abstract

The basics of tilting pad bearing design are discussed to include limits of operation for load, speed, and metal temperature. Optimum temperature sensor locations are recommended for self-aligning and nonaligning tilting pads. Tilting pad bearing geometric properties and their influence on bearing and rotordynamics are addressed including the advantages and disadvantages of zero preloaded pads. Also, the advantages of increasing the pad axial length are shown. Example calculations are presented for the tilting pad pivot film thickness which is necessary to determine if the top pads are loaded or unloaded. Tilting pad static shaft sink and clearance measurement techniques are addressed. The equations to calculate normal force and break away torque are derived including an example calculation comparing a tilting pad bearing to a two axial groove bearing. Tilting pad bearing oil flow and temperature rise are included along with a discussion of reduced temperature tilting pad designs.