Hoop Stress in a Thin-Walled Pressure Vessel
Hoop Stress in a Thin-Walled Pressure Vessel
The hoop stress is the largest stress in a cylindrical pressure vessel and usually decides the wall thickness.
For a thin cylinder the hoop stress is σ_h = pD/(2t). where p is the internal pressure, D the internal diameter and t the wall thickness.
Inputs
p := 1.5 MPa=1.5 MPa
D := 800 mm=800 mm
t := 8 mm=8 mm
Apply the thin-wall hoop-stress formula.
sigma_h := p·D/(2·t)=75 MPa
Results
The hoop stress is twice the longitudinal stress, so cylinders tend to split along their length. Keep it below the allowable with the code’s joint efficiency and safety factor.
Assumptions & limitations
- Thin wall (D/t > 20), so stress is uniform through the thickness.
- Internal pressure only, no external loads.
- Away from end caps and nozzles.