"positive displacement mud motor"

수평 지향 시추용 다운홀 모터 PDM 양변위 머드 모터

A downhole motor (also known as a positive displacement motor, PDM, or mud motor) is a downhole drilling tool that converts the hydraulic power of drilling fluid into mechanical power to rotate the drill bit . Unlike conventional rotary drilling where the entire drillstring rotates from the surface, ...