Question:
A hole in a pressure vessel end plate repair casting is being drilled using a radial arm drill. The distance from the drill point to the centre of the drill column is 1.2m. The drill column is a tube having internal and external diameters of 25cm and 30cm respectively. If the force on the drill point is 30kN sketch the stress distribution across the drill column.

Answer:

Max bending stress occurs on outer fibres.

Left Edge stress calculation:

Right Edge stress calculation:

Stress distribution diagram:
