Problem 2: (10 Points) Schematic of a clutch-testing machine is shown. The steel shaft rotates at

a constant speed co. An axial load is applied to the shaft and is cycled from zero to 4000 lbs. The

resulting torque (T), generated by the friction, varies from 0 to 2000 lb-in. The shaft is made of

steel with Sy = 120 kpsi and Sut = 145 kpsi and Se= 42.5 kpsi. The stress-concentration factors

for the fillet are Kf = 2.8 for the axial and Kfs = 1.7 for the torsional loading, respectively.

Determine the safety factor.

Friction pad

R=0.1 in

TD-6 in

d=1.2 in