短语词组短语exhaust fan main shaft 风机主轴fan efficiency shaft gear 风扇轴驱动齿轮fan main shaft 风机主轴fan n shaft 通风井fan efficiency shaft 扇风机井fan turbine shaft 风扇涡轮轴fan cardan shaft 风扇万向轴Heung Fan Liu Shaft 香粉寮竖井fan maim shaft 风机主轴 返回 fan shaft