Análise do comportamento operacional de mancais axiais hidrodinâmicos de sapatas setoriais pivotadas

Abstract

A theoretical and experimental analysis on the behavior of a hydrodynamic tilting pads thrust bearing is presented. The experimental work was carried out on a vertical shaft test rig. The test bearing was a Kingsbury KV9” tilting pad thrust bearing consisted by six sector shaped pads with spherical pivots positioned at 66% of the pad angle. A full description of the test-rig, test-bearing and instrumentation is presented. Bearing friction torque and pad undersurface temperatures, plus the oil temperatures at the inlet and outlet of the bearing housing were measured for a wide range of rotational speeds, thrust loads and oil flow rates delivered to the bearing. An attempt was also made for measuring the oil film thicknesses at some points between the rotating collar and one of the pads. The theoretical work was based on the isoviscous Reynolds equation for the hydrodynamic lubrication. The finite difference method was employed to obtain the pressure distribution over a pad and a FORTRAN computer program was developed for the calculation of the bearing operating parameters such as load carrying capacity, friction torque, power losses, oil flow rates at the pad boundaries and temperature rise. A series of tables and graphs were generated and, finally, a comparison between the theoretical and experimental results is presented.