Shell Manway Cover Thickness API 650

[KentCaudill]

Is there a formula for calculating the thickness of a shell manway cover plate based on the tank height. The table in API 650 is handy but I would like to use a formula in my spreadsheet to calculate the thickness given the tank height, corrosion allowance and so on. Thanks in advance, Kent.

Thanks for your help, Kent.

 

[Alengfo]

this is tricky, as it involves the effect of increasing head
fo rvery large tanks the flat plate cover rotation
We developed some curves for a client for a specialty tank insert box but got strain gauging done as we were so uncomfotrtable with the thin shell behaviour.
Try fepipe for a set of results
alk

 

[Alengfo]

this is tricky, as it involves the effect of increasing head
fo rvery large tanks the flat plate cover rotation
We developed some curves for a client for a specialty tank insert box but got strain gauging done as we were so uncomfotrtable with the thin shell behaviour.
Try fepipe for a set of results
alk

 

[MrVessels]

Section 3.7.5.4 of API 650 recommends the use of API 620 for the design of cover plates, manway necks etc. when utilizing hard gaskets but this can be used for other sheet type gaskets also. The reference is to section 3.20 and 3.21 of 620 but my version (10th Edition 2002) shows the correct sections to be 5.20 and 5.21.

The formulae are the same as UG-34 from ASME VIII Div. 1