Comparative Dry Wear of PTFE Liner Bearing in Cylindrical and Spherical Geometry

Abstract

Most fundamental laboratory studies in oscillating testing have been performed on cylindrical geometry. However, industrial applications focus generally on spherical geometry and extrapolation of results must be attempted. The same PTFE liner material with pitch structure has been considered in cylindrical and spherical geometry with oscillating amplitudes of motion and loads as study parameters. Other mechanical and thermal parameters were controlled on the two corresponding test rigs. Friction, wear, and degradations have been compared. Results have shown, particularly at small amplitudes and loads, that the geometry controls wear debris movement in the contact and explains differences in wear. Further, normal conformity or curvature difference between ball raceway and liner steel backing has been introduced.