Vacuum Collapse of Spiral-Wire Reinforced Hose

[rickd69]

I am having a tough time applying ring stiffener calaculations to my Rubber "vessels" that are Spiral-Wire reinforced. The wire I am using is hard drawn and has high tensile and yield values, but the EI=P*D^3*L/24 formula for collapsing pressure doesn't change for the higher value because it is E dependent. The E for the wire is the same as plain steel. Does anybody have any insight on this?

 

[jte]

I think the issue you're struggling with is strength vs. rigidity. Look at a basic Euler column: Its critical buckling load is not based on stress - yield and ultimate strengths do not play a role. Instead, its the rigidity as determined by the EI part of the equation which governs. As long as your failure mode is buckling the same basics will apply even though you have a different shape.

jt