A simultaneous testing facility for aerospace self-lubricated bearing liner materials

The paper describes a novel apparatus designed to test the wear rates of liner materials for self-lubricating bearings. Self-lubricating bearings have been in widespread use since the mid-1950s, predominantly in the aerospace industry where they have the advantage of being low maintenance components. They are commonly used in reciprocating applications such as control surface actuators, and usually consist of a spherical bearing with the inner and outer elements separated by a composite resin-bonded textile liner. The apparatus differs from similar machines in that it is designed for reciprocating contact, to simulate motions encountered in helicopter main rotor pitch link bearings. Additionally, it is designed to test up to 4 samples at the same time, reducing the effect of variability in environmental conditions such as temperature or humidity. This paper describes key aspects of the test rig along with initial results