Elastic Strength of High Pressure Vessels with Offset Circular Cross Bore

The study sought to establish the optimal location of a small circular cross bore with increased safe working pressures, using Von Mises and Tresca elastic failure theories. Cross bored thick cylinders with closed ends having thickness ratio ranging from 3.0 down to 1.4 were studied. The investigation was carried out on a small circular cross bore at 9 different offset locations along the longitudinal X axis plane of the cylinder. These offset location ratios were between 0 and 0.9. A total of 63 part models were created and analysed using a three-dimensional finite element analysis software. It was found that the magnitude of the working stress that can be reclaimed from the lost proportion of the pressure carrying capacity when a cross bore is located optimally ranged from 8.61% to 19.51 % and 7.99% to 17.02 % for Von Mises's and Tresca's theories, respectively. Further, the magnitude of the optimal working stress concentration factor calculated using on Mises's theory occurred at K = 1.75 with a magnitude of 1.975. Whereas, the respective optimal magnitude obtained using Tresca's theory was 1.837 at K = 2.5