pyöriväporauksella

Pyöriväporaus, known in English as rotary drilling, is a drilling technique used to excavate holes in the earth's crust. It is the most common method for drilling oil and gas wells, as well as for water wells and geotechnical investigations. The process involves rotating a drill bit attached to a drill string. This rotation, combined with downward force, grinds and breaks up the rock or soil, creating a borehole.

The drill string, typically made of steel pipes, transmits rotational power and weight to the drill bit. As the drilling progresses, sections of pipe are added to the string to extend its length. A drilling fluid, often called mud, is pumped down through the hollow drill string and returns to the surface through the annulus (the space between the drill string and the borehole wall). This fluid serves multiple purposes: it cools and lubricates the drill bit, flushes out the cuttings (fragments of rock and soil), and helps to stabilize the borehole walls by forming a filter cake.

Various types of drill bits are used, depending on the rock formation being drilled. Common types include roller cone bits, which use rotating cones with teeth or cutters, and fixed cutter bits, such as diamond or tungsten carbide bits, which use a stationary cutting surface. The selection of the appropriate drill bit and drilling fluid is crucial for efficient and safe drilling operations. Pyöriväporaus allows for relatively fast penetration rates and the creation of large-diameter holes compared to other drilling methods.