Maintenance-free radial Spherical Plain Bearings with sliding contact surface combination steel/PTFE sintered bronze and those with steel/PTFE fabric are suitable for heavy, constant direction loads, where low friction is required. They have a limited suitability for alternating loads as well as shock loads.
Bearings with sliding contact surface combination steel/PTFE FRP are suitable for heavy, constant direction loads, where low friction is required. They have a limited suitability for alternating loads as well as shock loads and they are relatively insensitive to contaminants.