Here is Canvas object wihch demonstrate the problem.

The tank is filled with a fluid that has an internal gage pressure of p = 1,500 kPa. The fluid pressure creates stresses in the tank wall.

The fluid pressure creates a normal stress in the wall parallel to the longitudinal axis of the tank. The longitudinal stress is related to the tank pressure p by:

where r = inside radius, d = inside diameter, and t = wall thickness.