... ,TYPE02,TYPE05, TYPE11,TYPE12,TYPE13GBGB9112~9125-88 GB/T13402-92GOSTGOST 12820-80 12821-80SpecificationClass150#,300#,400#,600#,900#,1500#,2500#,PN0.25 ... ,PN0.6,PN1.0,PN1.6,PN2.5,PN4.0,PN6.3,PN10.0 ... 2.Material Sectioning 3. Heating 4. Forging 5. Heat Treatment 6.Cutting7. Inspection Weld Neck Carbon Steel Flange