Oil & Gas abbreviations/اختصارات نفت و گاز

Calliper: tool for checking casing in a well for deformation

CALM: Catenary Anchor Leg Mooring

Calorific value: Quantity of heat produced by complete combustion of a unit weight of a material

Cantilevered jack up: Jack up drilling unit where the drill rig is mounted on two cantilevers

CAPEX: Capital expenditure

Cap rock: A relatively impermeable rock, that forms a barrier or seal above and around reservoir rock

Casing: Large-diameter pipe lowered into an open hole and cemented in place

Catenary: The natural curve assumed by a chain or cable suspended between two points (e.g.an anchor chain)

cc: Cubic centimeter (cm3)

CBM: Coal bed Methane, natural gas extracted from coal

CCR: Central Control Room

CCS: Carbon Capture and Storage

Cellar deck: Deck beneath the working floor of a drilling rig or below the main deck of an offshore platform

Centipoise (cP): A unit of measurement for viscosity

Check valve: A mechanical device that permits fluid to flow or pressure to act in one direction only

Choke: Device incorporating an orifice that is used to control fluid flow rate or downstream system pressure

Christmas tree (Xmas Tree): The set of valves, spools and fittings connected to the top of a well to direct and control the flow of formation fluids from the well

Clastic Rock: Rock which has been formed from sediment of other rocks e.g. sandstone, shale, conglomerates, etc.

Cloud Point: The temperature at which a solution of a surfactant or glycol starts to form micelles (molecular agglomerates)

CNG: Compressed Natural Gas

Co2: Carbon dioxide

Coal Bed Methane (CBM): Natural gas extracted from coal beds

Coal Seam Gas (CSG): Natural gas extracted from coal beds

Concession: A grant extended by a government to permit a company to explore for and produce oil, gas or mineral resources in an area or block

Condensate: Low density, high API gravity liquid hydrocarbon phase that generally occurs in association with natural gas

Conductor casing: Generally the first string of casing in a well

Conductor pipe: The casing string that is usually put into the well first, particularly on land wells, to prevent the sides of the hole from caving into the wellbore

Coning: The change in oil-water contact or gas-oil contact profiles as a result of drawdown pressures during production

Continental shelf: The area at the edge of a continent from the shoreline to a depth of 200m, where the continental slope begins

Conventional: A reservoir in which buoyant forces keep hydrocarbons in place below a sealing caprock.

Core: To deepen the wellbore by way of collecting a cylindrical sample of rock

Coring: The process of cutting a vertical, cylindrical sample of the formations

Cp: Centipoise, A unit of measurement for viscosity (See Centipoise)

CPF: Central Processing Facility

CPU: Central Processing Unit

CRA: Corrosion Resistant Alloy

Cretaceous: Rock formed in the last period of the Mesozoic era, between the Jurassic and the Tertiary periods, during which chalk deposits were formed.

Crude Oil: A general term for unrefined petroleum or liquid petroleum

CSG: Coal Seam Gas. Natural gas extracted from coal beds

Cuttings: Small pieces of rock that break away due to the action of the bit teeth