Standards:GB/T1228_1231
Japanese standard:JIS B 1186
American standard:ASME B 18.2.6(ASTM A325 A490)
German standard:DIN 6914_6916
Application: construction of industrial and civil buildings,railway Bridges,highway Bridges,pipelineBridges,boiler frames, large-span industrial plants, high-rise civil buildings,various tower blocks and other steel structures.