Rotary Mud Drilling

This drilling method (with mud pump for flushing) can be direct circulation and reverse circulation, with tricone bit, drag bit and etc. Nevertheless, the torque is relatively critical for this drilling method. It is widely used in soft to medium hard ground conditions.

Rotary Mud Drilling

Rotary Mud Drilling (RMD) is the most commonly used method of drilling. In direct RMD water or water with additives/mud is pumped down a drill pipe out through ports or jets in the drill bit. The fluid then flows up the space between the hole and drill pipe, known as the annular space. The fluid carries the drill cuttings in suspension to the surface of the borehole. At the surface the fluid is channelled into settling pits or tanks where most of the cuttings settle out. Clean drill fluid is then picked up from the opposite end of the settling area. The drilling fluid is then re-circulated down the hole, the process is repeated until the drilling is complete
http://www.roundonedrilling.co.za/about/
http://www.hdengineering.com/Application/rotary.htm

Mud rotary drilling is most commonly used to create a stable hole that can then be used for other purposes, such as to create water wells, or for seismic testing.

There are three main types of rotary mud drilling:
Rotary drilling with the rods in tension
Slim hole rotary with the rods in compression
Single tube reverse circulation.

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