SF-S Double Metal Bearing SF-S Double Meatal Bearing takes steel plate as the base and with the sintering of alloy of tin and bronze on the surface. the bronze layer is sintered twice under high temperature and calendered firmly in the strip. The high bonding strength load capacity and fatigue make it with stand medium load and low speed high load condiyions, It was widely used in the following field as automobile engines,motorcycle cluth. Light machanical machines civil engineering machines and so on..