PIPE Flange Dimension Max. Working Pressure PSI Bolt Dia. No. of Bolt Holes (Elongation) SizeInchesmm O.D.Inchesmm AInchesmm BInchesmm 2"50 2.37560.3 6.30160 2.37560.3 300 5/8" 4 2-1/2"65 3.00076.2 7.125181 2.37560.3 300 5/8" 4 2-1/2"65A 2.87573 7.125181 2.37560.3 300 5/8" 4 3"80 3.50088.9 7.625194 2.37560.3 300 5/8" 8 4"100 4.500114.3 8.625219 2.37560.3 300 5/8" 8 5"125 5.563141.3 9.840250 2.56365.1 300 3/4" 8 6"150 6.500165.1 11.10282 2.56365.1 300 3/4" 8 6"150A 6.625168.3 11.10282 2.56365.1 300 3/4" 8 8"200 8.625219.1 13.30338 3.00076.2 300 3/4" 8