YB/T 137-1998 Twenty roll mill forged steel work rolls

YB/T 137-2024 Twenty roll mill forged steel work rolls

GB/T 222-1984 Method of sampling steel for determination of chemical composition and permissible variations for product analysis GB 223.5-1988 GB/T 223.10-1994 GB/T 223.11-1991 Methods for chemical analysis of iron, steel and alloy The ammonium persulfate oxidation volumetric method for the determination of chromium content GB 223.13-1989 GB/T 223.22-1994 Methods for chemical analysis of iron, steel and alloy The nitroso-R-salt spectrophotometric method for the determination of cobalt content GB/T 223.26-1989 Methods for chemical analysis of iron, steel and alloy The thiocyanate direct photometric method for the determination of molybdenum content GB/T 223.43-1994 Methods for chemical analysis of iron, steel and alloy—Determination of tungsten content GB/T 223.62-1988 Methods for chemical analysis of iron,steel and alloy—The butyl acetate extraction photometric method for the determination of phosphorus content GB/T 223.63-1988 Methods for chemical analysis of iron,steel and alloy—The sodium(potassium)periodate photometric method for the determination of manganese content GB 223.68-1989 GB 223.69-1989 GB/T 226-1991 Etch test for macrostructure and defect of steels GB/T 230-1991 GB 1184-1980 GB 1299-1985 GB/T 1804-1992 GB 4879-1985 GB/T 9943-1988 High speed tool steel bars—Technical requirements GB/T 10561-1989 Steel—Determination of content of non-metallic inclusion—Micrographic method using standard diagrams GB/T 13298-1991 Metal—Inspection method of microstructure GB/T 13313-199 ZB J04 006-1987 ZB J36 003-1987 YB/T 036.21-1992 Metallurgical equipment manufacturing general technical requirements for packaging GB/T 223.58-1987 Methods for chemical analysis of iron，steel and alloy--The extraction-absorption catalytic polarographic method for the determination of manganese content