Analysis of Torque Transmission

In the figure, the frictional surface has an outer radius, r0, inner radius ri.      

Assume an elemental surface area of thickness dr at a radius of r from the centre. If p is the pressure exerted while putting the two discs A and B together.

ro – radius of outer end of the clutch facing

ri – radius of inner edge of clutch facing

dr – thickness of the elemental element of clutch facing at a distance of r from the centre

Total axial force, df = p.dA

df = p.2πr.dr

F = 2π

The torque that can be transmitted

Case I : If pressure is constant i.e. p=k

Case II: if wear is constant i.e. p.r = constant