A pumped storage hydroelectric generation station needs a need water pipe that has a $36$ inch nominal

diameter. The pipe material is carbon steel with a yield strength of $30$ ksi $.$ The station operator

insists on the lowest costs while maintaining a factor of safety of $10.$ If the operating pressure is $100$

psig, find the required pipe wall thickness.

A table with the standard pipe wall thickness and its corresponding inside diameter $($for $36$ inch

nominal pipe$)$ is given in the table below. Please pick the wall thickness that best suites this

customer's need.

$($Note that the sum of the inside diameter and double the wall

thickness must equal $36$ inches.$)$