SKF PTFE composite bushings are available as straight bushings in inch sizes. These bushings are self-lubricating as well as maintenance-free and due to their low friction provide a long service life. Despite of their compact design, they can accommodate heavy radial loads and are suitable for relatively slow rotational or oscillating movements. They also have good dimensional stability and thermal conductivity.
PTFE composite bushings consist of a sheet steel backing on which a 0,2 to 0,4 mm thick porous layer of tin/bronze is sintered. Furthermore, by a rolling process the pores of the sintered layer are filled with a mixture of PTFE (polytetrafluoroethylene) and molybdenum disulphide additives. This additional 5 to 50 μm thick running-in layer provides an optimum combination of the mechanical properties of the sintered tin/bronze and the good sliding and lubricating properties of the PTFE mixture.
Running-in period During a short running-in period, minute amounts of the PTFE material from the running-in layer are transferred to the counter surfaces. After this transfer has taken place, the characteristics low friction and wear properties of these bushings are reached.