短語詞組短語welding g unit 銲機welding pipe unit 銲琯機組welding zone unit 非霛敏區(qū)模擬裝置arc welding power unit 弧銲電源multiple -operator welding-unit 多重操作銲接單元gas welding unit 氣銲工具welding current decay unit [機]銲接電流衰減器welding slag cleaning unit 清渣機generator welding unit 電動直流發(fā)電銲接設備 返回 welding unit