... , 1500Lbs, 2500Lbs, /PN6,PN10,PN16,PN20,PN25,PN40/ Class A, B, C, D, EstandardASME B16.5, ASME B16. ... , passed the Authentication of API and became a member of first – grade supply network of ... Bureau.It was recognized by China Classification Society and admitted an associator by EnergyAhead Sources Net of ... GOST12821-80); Steel Butt-Welded Flanges GOST12821-80Pressure Class:PN=0.6--PN10,0 (100 /2)SIZE ...