Rotary drilling Rig

Description

In rotary drilling method, a cutting bit is attached to a hollow drill rod rotated rapidly by an engine driven rotary table. Either water or a suspension of colloidal clay is pumped down the drill pipe, flows through opennings in the bit and transports the loosened materials to the surface. The clay suspensions are designed to reduce loss of drilling fluid into permeable formations, lubricate the rotating drill pipe, bind the wall against caving and suspend the cuttings.