常見例句雙語例句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.由于梁翼緣的平坡口焊縫墊板結構存在，梁翼緣焊縫根部融合不良而形成“人工” 裂紋。 返回 lack of root fusion