... -DN1600 materail:ss,cs coating:rust proof oil Carbon Steel Forged GOST12821 PN6-63 WELDING NECK Russian Standard flange OUR INTRODUCTION: We are ... the pipefittings collection in th emost standard and material. FLANGE: WELDING NECK ,SLIP ON ,BLIND ,PLATE,THREADED,LAPPED ,SCREWDE,SOCKET ... WELDING GOST 12821-80 pressure :PN 6,PN 16,PN 10, ...