Description: Consider a pressure vessel that is made of two half spherical domes with 1 ft in diameter, and the cylinder portion is 3 ft in length and is subjected to 100 psi pressure. The maximum tensile strength of the material is 55 ksi The factor of safety for this design is 1.5. Problem: Determine the minimum thickness for this design.

0.016 in

Explanation:

1 ft = 12 in. So the radius r = 6 in

3 ft = 36 in

55 ksi = 1000 psi

The longitudinal stress of the vessel can be calculated as the following:

where p = 100 psi is the internal pressure, t is the wall thickness

The hoop stress can be calculated as the following

As 0.011 > 0.0054 we will pick t  = 0.011 as design to withstand the maximum stress. Taking into account of factor of safety design, the appropriate thickness is 0.011*1.5 = 0.016 in