Coupling Parts made from Hard and Soft Materials 1

Frictional units incorporating parts made from hard and soft materials must be designed so that the rubbing surface of the harder and more wear-resistant material overlaps completely the rubbing surface of its mating member made of a softer and less wear-resistant material. Observation of this rule assures a uniform wear of the softer part. If the soft surface overlaps the harder one, a stepped worn spot appears which impairs the operation of the unit. Bellow you can find some typical applications.