The mechanism of lubrication of cam-follower systems and of rolling contact friction drives is essentially elastohydrodynamic. Existing knowledge of the design criteria to be satisfied by and the major forms of failure—fatigue pitting and scuffing—encountered in these mechanisms is discussed in the light of elastohydrodynamic theory. Examples of the successful application of the theory are reviewed. The role of development testing in rigs and in full-scale equipment is considered and the conclusions reached from such testing briefly summarized.
The coefficient of friction in the contact is an important factor in the operation of rolling contact friction drives and its variation with operating conditions is complex. Knowledge of the frictional behaviour of elastohydrodynamic contacts is not complete; the present position is reviewed.
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