GAS CYLINDER

WHY GAS CYLINDERS AND ALL OTHER HIGH PRESSURE THINGS ARE CYLINDRICAL IN SHAPE?

Gas tanks are made in cylindrical shapes , although spherical shape is twice the strength of cylindrical pressure vessel.
But spherical shape cylinders are not used because of two main reasons :-

(1.) complex manufacturing procedures.
(2.) difficult to transport.

Because gas cylinders contain high internal pressure so we cannot use shapes like rectangle and cube because there will be many stresses associated with such shapes.

While in case of a cylinder , only hoop and longitudinal stresses are present.Rectangular and cube designs will be more prone to failure at corners due to bending stresses and welding failures.So,cylindrical shape is used.