These heads are not suitable for pressure vessel.
And not recommemnded for tank or vessel with external loads
The inside knuckle radius -typically 3X thickness
Typical thin out allownace-1/2' and under-add 0.03125' to the minimum thickness
Over 1/2' -add 0.0625 to the minimum
Parameters are given as reference only, pls contact with me for your specific inquirys
Audited Supplier 
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