Standard specification for hot - formed welded and seamless high - strength low - alloy structural tubing 热塑焊接和无缝高强度低合金结构钢管的标准规范
High quality carbon structural round bloom , seamless tube bloom used in high pressure boiler , alloy structural steel tube blooms are all up to the general standard 优质碳素结构钢圆管坯,高压锅炉用无缝管坯,合金结构钢管坯等均达到国标中的各项要求。