Rotatsioonpuurimise

Rotatsioonpuurimine, also known as rotary drilling, is a drilling method used primarily in the oil and gas industry, as well as in mining and construction. This technique involves rotating a drill bit attached to a drill string, which simultaneously cuts and grinds the rock formation. The rotation is driven by a motor, typically a top-drive or a rotary table located on the drill rig's derrick.

A crucial component of the rotary drilling process is the circulation of drilling fluid, often referred to as "mud." This fluid is pumped down through the hollow drill string, exits through nozzles in the drill bit, and then flows back up to the surface through the annulus between the drill string and the borehole wall. The drilling fluid serves multiple purposes: it cools and lubricates the drill bit, flushes away rock cuttings, stabilizes the borehole walls, and helps control subsurface pressures.

The drill string, which can be very long, consists of interconnected sections of drill pipe. The drill bit at the end of the string is designed to break down specific rock types. Common types of drill bits include roller cone bits, which use rotating cutters, and fixed-cutter bits, which have cutting elements embedded in a hard matrix. The rate of penetration depends on factors such as the type of rock, the drill bit design, the rotational speed, and the weight applied to the bit.