The high pressure pipe is initially designed to be solid steel with a bore of 50 mm and outside diameter of 90 mm. Throughout a pressure test the pipe was found to fail at 120MN/m².

Q1. Determine the hoop, radial longitudinal stresses in the pipe at this pressure.

Q2. Draw a Mhor’s circle exhibiting the stress condition of an element at a point where failure is most probable.

Q3. If the yield stress of steel was measured as 350MN/m² throughout a tensile test, propose which failure theory would predict the pressure at which the pipe failure should take place.