... 2502 1) Production name:flat flange, welding neck flange, slip-on flange, socket welding flange, blind flange.2) Size range:1/2"-48"(dn15-dn1200)3 ... ) CE and certification:ISO9001-2000,BV,SGS,LOYID 6) Application range: petroleum, Chemical, power, gas, metallurgy, shipbuilding, construction, nuclear power ,etc ...