The rotating power of the drill bit for the drilling process comes from two parts:
1, the torque transmitted by the turntable;
2, the torque transmitted by well bottom hydrodynamic drill (screw drill)
Most of the weight of the drill is on the big hook, a small part of the pressure on the drill head, applied to the drill bit of this part of the gravity called drilling pressure. In addition to the mechanical rock breaking of the drill bit, there is also the hydro-breaking effect caused by the high-speed jet formed by the drilling fluid at high pressure at the drill bit water eye. Drilling fluid is called drilling blood, its role can carry rock chips, transfer hydro-power, cooling drilling tools, in the well wall to form mud cake to reduce resistance. Therefore, a good drilling fluid can greatly improve the drilling speed, reduce the accident rate underground. The most important thing is that each type of drill has the maximum torque, the normal drilling process will generally not exceed that value.