AutoPIPE Vessel Critical Defect- CODAP C3.1.9: beta_k coefficient is not correctly considered in the calculation of the thickness ey

A critical defect has been detected in the recently released AutoPIPE Vessel CONNECT Edition v41 (version 41.00.00.005).

The issue is as follows:

CODAP 2015:2018-07

C3.1.9 - Opening located in the knuckle of a torispherical or elliptical end.

The βk coefficient is not correctly considered in the calculation of the thickness ey.

This can lead to non-conservative results!

The issue is due to the calculation of β.

The value of coefficient β is given by formulas as a function of thickness of peripheral region e , radius R and ratio r/Di , therefore it shall be determined by trial and error method when the thickness ey is to be determined, the iterative calculation being repeated until the value ey given by formula C3.1.5.1 c is equal to that used to calculate the coefficient β.

We correctly considered βk when the initial thickness ey is to be determined.

But, unfortunately, the iterative calculation doesn’t consider βk!

Sometimes, the initial value is close to the final value, this explains why the problem is not always visible/detectable (especially for elliptical head). But, all types of head are impacted (elliptical and torispherical).

The issues has been resolved and will be available in the upcoming replacement build of v41 (41.00.00.005 will be replaced by 41.00.00.006 which has the fix).