Dished End Plates.- The maximum working pressure of
dished end plates with pressure on concave side
shall be determined by Regulations
276 to 278.
The value of E may be taken as unity when the diametral
cross sectional area of the compensating frame and/or
ring is equal to or greater than the diametral cross-sectional
area of the opening in the end plate to be compensated.
For ends which are butt welded to the cylindrical
parts of the shell the thickness of the edge of the
flange for connection to the cylindrical part of the
shell shall be not less than that required for seamless
unpierced shell as determined by Equation 72.