ASME VIII-1, Appendix 13, Vessels of non-circular cross sections

[valenak]

Hello everyone!
Please sorry my English. I've tried to make my questions to sound reasonable with a help of almighty Google translator.

Pressure vessel of rectangular cross section externally reinforced by u-beams. U-Beams form a jacket around an inner vessel. Vessel operates under vacuum -14.7 psi gauge and and the steam jacket has 45 psig. As i understand,vessel has to be calculated with ASME VIII-1 Appendix 13-8. My questions are: should be the inner walls of a vessel be calculated with 45 psig + 14.7 psig and outer surfaces with 45 psig only? Shall i use in fomulas for membrane and bending stresses dimentions of a inner vessel (H and h) or shal i use e.g. (H+2xbeam height) sinse there is a load case, when pressure in a chamber and a jacked is 45 psig?

Thank you!

 

[muld0020]

I'm not sure I follow your full situtation, but if you have a non-standard type design (not explicatly in the App13 calcs) or a design to external pressure (13-4(e))you should consider U-2(g), the U-2(g) can be satisfied with Finite Element Analysis and may be the easiest solution.

 

[cloa]

valenak- while your description of the your pressure vessel may be clear enough as you have done- a fully detailed diagram always helps. Attach it through the upload your file to ENGINEERING.com link.