短语词组短語double butt strap seam 雙襯板對接縫butt welding seam 對接銲縫mitred butt welded seam 斜對接銲縫butt welded seam 對銲縫butt weld seam 對接縫butt welds seam 對接銲縫resistance butt -seam welding [電]電阻對縫銲接butt -seam-welding 對縫銲 返回 butt seam