短语词组短语bottom header pipe 闸门底部放水管;闸首底部放水管Header pipe tubes for PF -condenser 平行流冷凝器主管pipe header 管子联箱;带连接管的配水干管;联管箱boiler pipe header 锅炉集箱Heat exchange pipe header 换热管联箱 返回 header pipe