1. 1 - An AISI 1020 cold- rolled steel tube has an OD of 3.0 inch. The internal pressure in the tube is 6,840 psi. Determine the thickness of the tube using the maximum shear stress theory and a safety factor of 1.5 against yielding. Use thick-walled cylinder equations. What would be the thickness of the tube if you assumed thin-walled cylinder? 6840

2. 2 - A gear is to be press fitted onto a shaft. The gear and the shaft are made of a steel with the same yield strength (Sy = 60,000 psi). The gear has to be able to transmit 50 hp at 2000 rpm. Assume a coefficient of 0.2 between the hub and the shaft. The nominal (basic) shaft diameter is 0.75 inch and the hub has an outside diameter of 1.5 in. and a length of 1.5 in.

3.  t =  r = - p (contact pressure) Stress on the surface of the shaft, r i = 0