Top Drive: Key Technology to Simplify the Drilling Process

Used to rotate the drill string during the drilling process, the top drive is a motor that is suspended from the derrick, or mast, of the rig. These power swivels boast at least 1,000 horsepower that turns a shaft to which the drill string is screwed. Replacing the traditional Kelly or rotary table, the top drive lessens the manual labor involved in drilling, as well as many associated risks.

A top drive is comprised of one or more electric or hydraulic motors, which are connected to the drill string via a short section of pipe known as the quill. Suspended from a hook below the traveling block, the top drive can move up and down the derrick. Many times, slips are still employed on a rotary table to ensure the drill string does not fall down the well.