Ballooning (deflection due to pressure) 1

[BrettARichard]

Can someone lead me in the right direction of how to calculate the diametral enlargement (ballooning) of a thin walled piece due to the effects of pressure.

 

[CRG]

Look in "Roark's Formulas for Stress & Strain," by Warren C. Young.

 

[JStephen]

For elastic action, the hoop stress is P/(Rt), where P is internal pressure, R is radius, t is wall thickness. Calculate hoop strain from strain = stress/E, and calculate change in radius = strain x Radius.

This is the uniform radial enlargement due to pressure. I wouldn't call it "ballooning" as when that happens in a balloon, it is highly non-linear. I doubt Formulas For Stress and Strain covers the inelastic case, as that would be dependent upon the stress-strain curve.