短语词组短语oil drilling -rig electric drive system 石油钻机电传动系统oil -drilling rig mechanic 石油钻探钻机技工的oil consumption per rig -month 每钻机台月耗机油量;每钻机月消耗机油Oil -film bearing test rig 油膜轴承实验台 返回 oil-rig