API 6A Gate Valve Bonnet Flange Blot Stress

[HansonBoye]

Hi All,

I have a doubt in evaluating the stress by classical methods..
I could calculate the bolt load for operating condition and gasket seating condition and calculate the stress based on the reference below,

ASME Boiler and Pressure Vessel Code, VIII, Division 2, Alternative Rules, ‘Rules for construction of
Pressure Vessels’, July 2009, Page 400, 4.16.6, Design Bolt Loads and Page 405-407, Table 4.16.1 &
4.16.3 for Gasket Factor and Seating Stress

But using the above method does not evaluate the studded bolt thread area on the valve body shell.
Is there a way I could calculate the minimum wall thickness required for the body shell to withstand this bolt load?

Thanks!