local loading of nozzle on flat plate

[mtvessel1]

I have a rectangular vessel, which is stiffened such that the largest area of unstiffened flat side is not overstressed in bending, and the deflections calculated using Roark are deemed to be acceptable. The stiffeners have been designed and are satisfactory. (I think the stress limits are from PD5500 Annex A, but possibly ASME VIII). My question is;- how do you analyse an opening in the flat plate, which is under internal pressure AND combined with piping loads?? without the use of FEA?

looking forward to your assistance on this.
Thanks in advance.

 

[jte]

mtvessel1:

No such thing as a flat plate: As soon as you load up the tank you'll bend the plate between the stiffeners. Assuming that your nozzle is not right at a stiffener, you can take the radius of curvature of the plate as the radius. There will be two radii, one longitudinal and one circumferential. I'd use the higher radius and neglect the stiffening effect of the smaller radius for stress calc's.

The radius may be high, on the order of a hundred feet, which could put you out of the range of WRC calcs. In this case, use API-650 Appendix P.3 (the Alternate method published with the Fall 2003 Addenda)can be used for your nozzle stress analysis.

Let us know how it works out.

jt

p.s. It wouldn't hurt to fill out the "Tell Other Members About Yourself" section in the Personal Profile that you get to on from the box in the top left of the web site. Click on the "jte" at the top of this reply to see mine.