| Materials The materials used for the rod end housings of SKF maintenance-free rod ends are listed in Table u . The right is reserved to make changes dictated by technical developments. Details of the materials used for the maintenance-free spherical plain bearings incorporated in the rod ends will be found in Matrix m , page 73. The inner rings of rod ends with the sliding contact surface combination steel/PTFE composite are of bearing steel which is hardened and ground and the sliding contact surface is hard chromium plated. The sliding layer of these bearings consists of a glass fibre reinforced polymer containing PTFE. Permissible operating temperature range The permissible operating temperature range for SKF maintenance-free rod ends is governed by the rod end housing, the spherical plain bearing manufacturer incorporated and the bearing seals. The ranges are given in Table [5 . Fatigue strength In applications where the rod end is subjected to loads of alternating magnitude or direction, or where rod end failure could be dangerous, it is necessary to check the fatigue strength of the rod end. |