常见例句双语例句As backing bar for grooved weld on beam flange exists, artificial crack is formed because of lack of fusion at the root of flange weld.由于梁翼缘的平坡口焊缝垫板结构存在，梁翼缘焊缝根部融合不良而形成“人工” 裂纹。 返回 lack of root fusion