按照焊缝质量级别确定的原则，将焊缝级别分为三个等级；

Steel welds are classified into three grades in order to evaluate their quality.

youdao

按照焊缝质量级别确定的原则，将焊缝级别分为三个等级；

Steel welds are classified into three grades in order to evaluate their quality.

youdao