Friction and Lubrication in Machines

Abstract

The nature of causes of friction, together with some of its commonly experience manifestations, have been discussed in chapter 2. Generally speaking the effect of friction in machines is either to prevent slipping or to dissipate energy between two contacting parts. For example, a vehicle needs a high friction force between the driving wheels and the road to achieve maximum acceleration and cornering speed without skidding, and a high brake friction to minimise stopping distance.