GB/T 41217-2021 City metro and composite pipe gallery hot-rolling channel

GB/T 197-2003 General purpose metric screw threads—Tolerances GB/T 197-2018 General purpose metric screw threads—Tolerances GB/T 222-1984 Method of sampling steel for determination of chemical composition and permissible variations for product analysis GB/T 222-2006 Permissible tolerances for chemical composition of steel products GB/T 470-1997 Zinc ingots GB/T 470-2008 Zinc ingots GB/T 2522-1988 Magnetic sheet and strip—Methods of measurement of interlamination resistance and lamination factor and coat adhesiveness GB/T 2522-2007 Methods of test for the determination of surface insulation resistance and lamination factor of electric sheet and strip GB/T 2522-2017 Methods of test for the determination of coating insulation resistance and coating adhesion of electrical strip and sheet GB/T 2829-2002 Sampling procedures and tables for periodic inspection by attributes (Apply to inspection of process stability) GB/T 3098.1-2000 Mechanical properties of fasteners—Bolts, screws and studs GB/T 3098.1-2010 Mechanical properties of fasteners—Bolts,screws and studs GB/T 3098.2-2000 Mechanical properties of fasteners—Nuts—Coarse thread GB/T 3098.2-2015 Mechanical properties of fasteners—Nuts GB/T 3103.1-2002 Tolerances for fasteners—Bolts, screws, studs and nuts GB/T 4336-2002 Standard test method for spark discharge atomic emission spectrometric analysis of carbon and low-Alloy steel(routine method) GB/T 4336-2016 Carbon and low-alloy steel—Determination of multi-element contents—Spark discharge atomic emission spectrometric method (routine method) GB/T 6394-2002 Metal-methods for estimating the average grain size GB/T 6394-2017 Determination of estimating the average grain size of metal GB/T 6461-2002 Methods for corrosion testing of metallic and other inorganic coatings on metallic substrates—Rating of test specimens and manufactured articles subjected to corrosion tests GB 8624-1997 Classification on burning behaviors for building materials GB 8624-2006 Classification for burning behavior of building materials and products GB 8624-2012 Classification for burning behavior of building materials and products GB/T 9286-1998 Paints and varnishes—Cross cut test for films GB/T 9286-2021 Paints and varnishes—Cross-cut test GB/T 10125-1997 Corrosion tests in artificial atmospheres—Salt spray tests GB/T 10125-2012 Corrosion tests in artificial atmospheres—Salt spray tests GB/T 10125-2021 Corrosion tests in artificial atmospheres—Salt spray tests GB/T 13912-2002 Metallic coatings—Hot dip galvanized coatings on fabricated iron and steel articles—Specifications and test methods GB/T 13912-2020 Metallic coatings—Hot dip galvanized coatings on fabricated iron and steel articles—Specifications and test methods GB/T 14436-1993 General principles of industrial product guarantee documents GB/T 19292.1-2003 Corrosion of metals and alloys—Corrosivity of atmospheres—Classification GB/T 19292.1-2018 Corrosion of metals and alloys—Corrosivity of atmospheres—Part 1:Classification,determination and estimation GB/T 26784-2011 Fire resistance test for elements of buliding construction—Alternative and additional procedures TB/T 2073-2020 Electric Railway Concatenation Components Technical Specification TB/T 2074-2020 The testing methods for components of electrified railway contact network GB 50016-2014 Code for fire protection design of buildings GB/T 222-2025 Steels and alloys—Permissible deviations of product analyzed chemical composition GB/T 3098.2-2025 Mechanical properties of fasteners—Part 2:Nuts GB/T 2829-2025 Sampling procedures and tables for periodic inspection by attributes(Apply to inspection of process stability) GB 8624-2025 Classification for burning behavior of building materials and products