Moving components wear due to long time friction. When the gap between shaft and hole is worn to a certain extent, the parts must be replaced. Thus the designers choose to use materials with low hardness and good wear resistance, to reduce the wear of the shaft and seat. The replacement of the shaft sleeve or bush will save the cost of replacing the shaft or seat.For the above reasons, bushings are also used on connecting rods, camshafts, and pistons.
