短语词组短语intelligent drill -string 智能钻柱drill l string compensator 钻柱补偿器the drill pipe string 长石油管串drill pipe string 钻杆柱drill -string bending 钻柱弯曲tapered drill collar string 塔式钻铤组合;踏式钻铤组合Drill l String 钻柱 返回 drill string