Particular Cases:
(a) If the vessel is spherical
r1 = r2 = r and f1 = f2 = σh
∴ σh/ r + σh/ r = p/ t
σh = pr /2t = pd /4t
(b) If the vessel is cylindrical
r1 = r and r2 = ∞
∴ f1/ r = p/ t
Hoop stress,
f1 = pr /t = pd /2t
Since the longitudinal stress f2 is because of the pressure at the ends of the cylinder,
f2 × 2π rt = p π r 2
f 2 = pr/2t = pd/4t