Methodology within managed pressure drilling, Proactive Category; whereby bottomhole pressure is kept constant during connections to compensate the loss of annulus friction pressure (AFP) when mud […]

The depth of the wellbore at which a drilling contract is fulfilled.

A cylindrical sample taken from a formation for geological analysis. Usually a conventional core barrel is substituted for the bit and procures a sample as it […]

Laboratory analysis of a core sample to determine porosity, permeability, lithology, fluid content, angle of dip, geological age, and probable productivity of the formation.

A tubular device, usually from 10 to 60 ft (3 to 18 m) long, run at the bottom of the drill pipe in place of a […]

The part of the core barrel that holds the formation sample.

The cutting element of the core barrel assembly. In design it corresponds to one of the three main types of bits; drag bits with blades for […]

1) in piping, a metal collar with internal threads used to join two sections of threaded pipe. 2) in power transmission, a connection extending longitudinally between […]

A wellbore that has been unintentionally drilled in a direction other than vertical. It usually occurs where there is a section of alternating hard and soft […]

An assembly of sheaves mounted on beams at the top of the derrick and over which the drilling line is reeved. See block, reeve, sheave.

A rig that utilizes a hydraulically powered hoisting system with long stroke cylinders for pushing a sheave cluster and traveling assembly vertically. These cylinders and sheave […]