Skidding of High-Speed Roller Bearings in Aircraft Engine Applications

摘要

Modern jet engine main-shaft bearings operate at extreme temperatures, rotational speed and generally with condition of low radial load. Therefore, roller bearings, in contrast to ball bearings, are normally underloaded or it can be said that they are oversized for the available radial load. The rotating unbalance load is also relatively small in aircraft engine applications due to fine balancing of all rotating components during engine assembly. The shafts where bearings are mounted usually have a relatively large diameter due to other design criteria which must account for shaft bending, critical speeds, torque and sometimes the need to have a large, high capacity ball bearing nearby to accept excessive compressor and turbine loads which in most engines are not always well defined. The underloading of high-speed roller bearings together with fast acceleration and deceleration conditions are the primary cause of skidding and eventual adhesive wear in the metal to metal contact areas. Skidding is