短语词组短语oil outlet duct 排油管槽oil l duct 油道vertical oil -duct 纵向油道horizontal oil -duct 横向油道Oil -duct of core 铁芯油道connecting rod oil duct 连杆油道complex oil duct 复杂油道cargo oil duct 货油管道hot oil duct 热油导管 返回 oil duct