Thank you Arto,
The hole sizes are significant. The flange is a 2"-300lb with (4) 0.6" holes drilled tangent to the inside bore. I will look at the Roark Case but I think because the holes are not radial from the center this case may not apply.
I have a flange that has 4 presuure taps drilled from the OD of the flange through to the ID. Does anyone know a reference showing how to verify this arrangement and its application in a ASME Section VIII Div1 pressure vessel design? I am more concerned how to account for the loss of material...
