External stiffner ring with 16 mm diam holes. How calculate - validate

[seamantgn]

I have design a vertical vessel. It has 2 stiffners rings rectangular section. The owner said us it has issues with corrosion. Then propose include 16mm holes each 500 mm in the rings to avoid water acumulation.
Now de don't know how validate-calculate a ring cross sección. That configuration it is not in the asme VIII, 1, wich are using.

Using a ring with inertia of
cross section from the vessel wall to the point in wich the hole start equal or bigger than the required it's right?

Or how can we calculate the ring form this particular case?

Regards

Alejo

 

[racookpe1978]

Draw the proposed solution. You have not described it adequately to let somebody else understand what is the problem.

 

[Duwe6]

If you keep these holes well away from any edges or corners, and the holes are indeed round and smooth-edged, they can safely be ignored. Think of 2" 50mm and smaller nozzles into a shell or head; it is assumed in Sect VIII Div-1 that the stresses will smoothly flow around these holes, and not accumulate and cause localized problems. And this assumption works well, and is proven to be conservative.

 

[sharmass]

Design it for the minimum moment of inertia at the cross section of ring (taking those holes into considerations)