Thick vs Thin-Walled Pressure Vessel

[bhail]

Is there a standard that governs which method to use when analyzing pressure vessels? If so, did that standard change recently?

I ask because about half of the sources I have looked at require an r/t ratio of 20:1 in order to use the "thin-walled pressure vessel" method(including my 7th Ed. Shigley book) while most of the others allow a 10:1 r/t ratio (including the 3rd Ed. Shigley book).

Some papers online even go so far as to state a required r/t ratio of only 5:1.

I am interested in knowing what the current accepted standard ratio would be.

Thanks!

 

[vesselguy]

Suggest you check with the definitive source where the rules are defined which is the Code.

 

[bhail]

Unfortunately I currently don't have access to pressure vessel code at my company since we don't manufacture pressure vessels. I am simply trying to verify a supplier's calculations/methods.

 

[metengr]

bhail;
I must be missing something here, what exactly are you attempting to do by analyzing pressure vessels?? Formula's for determining minimum wall thickness are in the code of construction for pressure vessels. Don't try and reinvent the wheel. By the way, for pressure vessels built to Section VIII, Div 1, the equation for cylindrical pressure retaining items (shells) is applicable where the wall thickness does not exceed 0.5 R_i (internal radius).