can any body give me the guide lines (code references) for rectangular shaped vessel design subject to external (Full Vacuum) as well as internal pressure.

In my opinion the guidelines given in section VIII div. I for design of non circular vessels for positive internal pressure could be used for external pressure in case of flat walls as there is no any change in shape / geometry with respect to pressure. am i right?

please guide.

Thanks in advance.

For a flat plate there is no difference which side is in pressure. Mauro

Mauro, what about hydrostatic test pressure? Flat walls still are subject to collapse!

_________________
Konrad Anikiel

Appendix 13 provides for stiffeners to be used. Otherwise thk. should be too high. It is not a problem of Hydrostatic test only. First design for MAWP.
Mauro

I just meant that you're not right saying "there is no difference which side is in pressure". You calculate the HTP value in different way for inside and outside pressure. Also fatigue behaviour of the welds differs.

_________________
Konrad Anikiel