flange thickness based on diameter and test pressure

huangyhg

flange thickness based on diameter and test pressure
does anyone knows the formula for dimensioning the flanges thickness to blind the vessels for hydraulic tests?
the thickness is dependable of test pressure and diameter of the circular flange.
tks
es
roark's formulas for stress and strain have the equations, but you'll eat up a sheet of paper doing one, so i can't put it here.  
i found a simple calc for deflection in machinery's handbook.  keep deflection, d, to less than half the plate thickness, t.  d=.221wr**2/(et**3) where w is the total load.
the optimist sees the glass as half full.  yhe pessimist sees the glass as half empty.  the engineer see the glass as too large.