An operation made to determine the angle from which a bit has deviated from the vertical during drilling. There are two basic deviation-survey, or drift-survey, instruments; […]

A drilling bit that has a steel body surfaced with a matrix and industrial diamonds. Cutting is performed by the rotation of the very hard diamonds […]

A high-compression, internal-combustion engine used extensively for powering drilling rigs.

The power supplied to a drilling rig by diesel engines driving electric generators; used widely.

Intentional deviation of a wellbore from the vertical. Although wellbores are normally drilled vertically, it is sometimes necessary or advantageous to drill at an angle from […]

The first oil or gas well drilled in a new field that reveals the presence of a hydrocarbon-bearing reservoir. Subsequent wells are development wells. Compare development […]

A BOP control system that utilizes pilot hoses from the surface to transmit hydraulic pressure signals to activate pilot operate valves assigned to functions on the […]

In oilwell cementing, the fluid, usually drilling mud or salt water, that is pumped into the well after the cement is pumped into it to force […]

1) a small enclosure on the rig floor used as an office for the driller and as a storehouse for small objects. 2) any small building […]

A term applied to a sharp change in direction of the wellbore, usually resulting in abnormal fatigue to the drill stem and frequently resulting in key […]

A generic term applied to all types of thread lubricants.

A length of drill pipe, casing, or tubing consisting of two joints screwed together. Compare fourble, thribble. See joint.