Step 5. Compare the value of B determined in Steps 3
or 4 with the computed longitudinal compressive stress in
the cylindrical shell or tube, using the selected values of
t and Ro. If the value of B is smaller than the computed
compressive stress, a greater value of t must be selected
and the design procedure repeated until a value of B is
obtained that is greater than the compressive stress computed
for the loading on the cylindrical shell or tube.