Oilfield Terminology Part 1


in this post, you will find a big collection of Oilfield terms, that you may see in your textbooks, manuals and magazines. as an oilfield operator or engineer; you need to understand so many terms and abbreviations, for their importance and for the wide uses of them everywhere.

hope you make use of this list:

ABANDON – To cease efforts to produce fluids from a well, in depleted formation and to plug the well without adversely affecting the environment.
OR To cease efforts to produce oil or gas from a well, and to plug a depleted formation and salvage all material and equipment.

ABNORMAL OPERATING CONDITION – A condition which occurs in a process component when an operating variable ranges outside of its normal operating limits.

ABSOLUTE PRESSURE – Pressure measured from absolute zero pressure. It is ordinarily expressed as gage pressure (the pressure reading on a pressure gage) plus atmospheric pressure, and denoted in pounds per square inch absolute (psia).

ABSOLUTE VOLUME – The volume per unit mass, reciprocal of absolute density.

ABSORPTION – The penetration or apparent disappearance of molecules or ions of one or more substances into the interior of a solid or liquid. For example, in hydrated bentonite, the planar water that is held between the mica-like layers is the result of absorption.

AC FIELD – The active magnetic field produced by the use of alternating current.

ACCESS OPENING – An opening which allows communication to the interior of the flame arrestor housing making the mixer, pilot, burner, etc., accessible. This opening is normally closed by a flat plug or plate 3” to 4” in diameter, securely attached to the housing and tightly sealed against the opening.

ACID – Any chemical compound containing hydrogen capable of being replaced by positive elements or radicals to form salts. In terms of the dissociation theory, it is a compound which, on dissociation in solution, yields excess hydrogen ions. Acids lower the pH. Examples of acids or acidic substances are: hydrochloric acid, tannic acid, sodium acid pyrophosphateز

ACIDITY – The relative acid strength of liquids as measured by pH. A pH value below 7.

acidizingACIDIZING – The practice of injecting acids into rock formations to remove any blocking material or to enlarge the pores to enhance the movement of fluid through the rock.
OR The treatment of formations with hydrochloric or other type acids in order to increase production or injection.
OR The act of pumping an acidic solution into a wellbore to remove materials from the perforations, pipe, and walls of the producing formation or pumping the solution into formations to improve permeability.

ADHESION – A physical attraction, operating on the molecular level, exerted between the surfaces of bodies in contact.

ADJUSTABLE CHOKE A choke in which the position of a conical needle in a seat can be used to vary the rate of flow through the choke.

ADSORPTION – A surface phenomenon exhibited by a solid (adsorbent) to hold or concentrate gases, liquids, or dissolved substances (adsorptive) upon its surface, a property due to adhesion.
For example, that water held to the outside surface of hydrated bentonite is absorbed water.
OR The accumulation of a thin layer of molecules of gas or liquid on a solid surface.
OR The attraction exhibited by the surface of a solid for a liquid or a gas when they are in contact.

AERATE – Adding air into water by agitation.

ALKALINITY – The combining power of a base measured by the maximum number of equivalents of an acid with which it can react to form a salt. In water analysis, it represents the carbonates, bi-carbonates, hydroxides, and occasionally the borates, silicates, and phosphates in the water. It is determined by titration with standard acid to certain datum points.
OR The combining power of a base measured by the maximum number of equivalents of an acid with which it can react to form a salt. In water analysis, it represents the carbonates, bi-carbonates, hydroxides, and occasionally the borates, silicates, and phosphates in the water. It is determined by titration with standard acid to certain datum points.

ALLOY – A metal composed of two or more elements, at least one of which has good metallic properties.

AMINE – A compound generally used to “sweeten” sour fluids or gases.

ANILINE POINT – The lowest temperate at which equal volumes of freshly distilled aniline and an oil which is being tested are completely miscible. This test gives an indication of the character (paraffinic, naphthenic, asphaltic, aromatic, mid-continent, etc.) of the oil. The aniline point of diesels or crudes used in drilling fluid is also an indication of the deteriorating effect these materials may have on natural or synthetic rubber. The lower the aniline point of an oil the more severe it usually is in damaging rubber parts.

ANION – A negatively charged atom or radical, such as Cl-, OH-, etc. in solution of an electrolyte.

ANISOTROPIC FORMATION THEORY – Stratified or anisotropic formations are assumed to possess different drill abilities parallel and normal to the bedding planes, with the result that the bit does not drill in the direction of the resultant force.

ANNULAR FLOW – Formation fluids are produced up through the tubing-casing annulus and recovered at the surface.

ANNULAR PACKOFF – A mechanism that seals off annular pressure between the OD of a suspended tubular member or hanger and the ID of the head or thru spool which the tubular member passes or hanger is suspended.

ANNULAR PREVENTER – A device which can seal around any object in the wellbore or upon itself. Compression of a reinforced elastomer packing element by hydraulic pressure effects the seal.

ANNULAR SPACE – The space around a pipe (casing or tubing) suspended in a wellbore is often termed the ANNULUS, and its outer wall may be either the wall of the borehole or the casing.

ANTIFOAM – (Defoamer.) A substance to prevent foam formation by greatly decreasing
the surface tension.
OR A substance used to prevent foam by greatly increasing the surface tension.

APPARENT VISCOSITY – The viscosity a fluid appears to have on a given instrument at a stated rate of shear. It is a function of the fluid’s plastic viscosity and the yield point. The apparent viscosity in centipoises, as determined by the direct-indicating viscometer , is equal to ½ the 600-rpm reading. In a Newtonian fluid, the
apparent viscosity is numerically equal to the plastic viscosity. See also Viscosity, Plastic Viscosity, and Yield-Point.

ARTIFICIAL LIFT – The application of energy from an outside source to life reservoir fluids from a producing well. (GL)
OR Any method used to raise oil and gas to the surface after reservoir energy has declined to the point at which the well no longer produces by natural flow. The most common methods of artificial lift are sucker-rod pumps, hydraulic pumps, submersible pumps, and gas lift.

ARTIFICIAL LIFT EQUIPMENT – Equipment installed on, or in a well, to remove fluids from a well when it is no longer able to produce these fluids with its own energy, i.e. conventional rod pumping unit, hydraulic pump, submersible pump, gas lift, etc.

ASSOCIATED GAS – Natural gas which is in contact with crude oil in the reservoir.

ATMOSPHERIC PRESSURE – The pressure exerted over the surface of the earth b the weight of the atmosphere. At sea level, this pressure is approximately 14.7 pounds per square inch (psi).

BACK PRESSURE – The pressure resulting from restriction of full natural flow.
OR The pressure existing within the producing string at the surface in a gas lift well. Also used to designate the fluid pressure at the level of gas injection, the pressure against which the operating valve injects gas.
OR The pressure resulting from restriction of full natural flow of oil or gas.

BACK PRESSURE VALVE – A valve that permits flow in only one direction.
OR A one-way check valve that is installed through the X-mas tree, into the tubing hanger, and prevents well fluids from flowing out of the well.
OR A valve designed to control flow rates in such a manner that upstream pressure remains constant. May be operated by diaphragm, spring, or weighted lever.

BACKFLOW – Fluid flow in a process component opposite to the normal flow direction.

BAD OIL – Oil not acceptable for delivery to the pipeline purchaser because of too high BS&W; oil requiring additional treating.

BAFFLES – Plates or obstructions built into a tank or other vessel to change the direction of fluid flow.

BAILER – A long cylindrical container, fitted with a valve at its lower end, used to remove water, sand, mud, or oil from a well.

BARITE – A native crystalline barium sulfate, which occurs in snow-white crystalline masses, or grayish, reddish, and greenish ores with a specific gravity of 4 to 4.6. It is used for increasing the density of well cement slurries and drilling fluids.

BARREL – A volumetric unit of measure used in the petroleum industry consisting of 42 gallons.
OR common unit of liquid volume measurement in the petroleum industry. One barrel (1bbl) is equivalent to 42 gallons (158.97 liters).

Dome Roof Storage Tanks

BATTERY – Sometimes termed Tank Battery, is an area where storage tanks are installed to receive produced fluids. May include several tanks, and/or separation and treating equipment.

BATTERY (TANK BATTERY) – The production handling equipment on the lease.

B/D – The abbreviation for barrels per day. Other related abbreviations are: BPD for barrels per day; BOPD for barrels of oil per day; BWPD for barrels of water per day; BLPD for barrels of liquid per dayز

BENTONITE – A highly plastic, highly colloidal clay, largely consisting of the mineral montmorillonite, a hydrated aluminum silicate.
OR A plastic, colloidal clay largely made up of the mineral sodium montmorillonite; a hydrated aluminum silicate. For use in drilling fluids, bentonite has a yield in excess of 85 bbl/ton. The generic term “bentonite” is neither an exact mineralogical name or is the clay of definite mineralogical composition.

BHP – Bottom hole pressure.

BHT – Bottom Hole Temperature (F).

BIOCIDE – A chemical agent used to destroy bacteria in water systems.

BIT HYDRAULIC HORSEPOWER (BHHP) – The hydraulic horsepower equivalent of the gallons per minute and the pressure drop across the bit nozzles.

BIT STABILIZATION – Refers to stabilization of the downhole assembly near the bit; a stabilized bit is forced to rotate around its own axis.

BLEED – To drain off liquid or gas, generally slowly, through a valve called a bleeder. To BLEED DOWN, or BLEED OFF, means to slowly release the pressure of a well or of pressurized equipment.

BLIND RAM – An integral part of a “blowout preventer,” serving as the closing element. The ends of a blind ram are not intended to fit around the drill pipe but to seal against each other and shut off completely the space below.

BLIND RAMS (BLANK, MASTER) – Rams whose ends are not intended to seal against any drill pipe or casing. They seal against each other to effectively close the hole.

BLIND/SHEAR RAMS – Blind rams with a built-in cutting edge that will shear tubulars that may be in the hole, thus allowing the blind rams to seal the hole. Used primarily in subsea systems.

BLOWDOWN VALVE – An automatically operated normally open valve used to vent the pressure from a process station on shutdown.

BLOWOUT – An uncontrolled flow of well fluids from the wellbore.
OR An uncontrolled flow of well fluids and/or formation fluids from the wellbore caused by the formation pressure being greater than the hydrostatic head of the fluid in the hole.
OR  An uncontrolled flow of gas, oil, or other fluids from a well.
OR An uncontrolled flow of well fluids and/or formation fluids from the wellbore or into lower pressured subsurface zones (underground blowout).

BLOWOUT PREVENTER – A device attached immediately above the casing, which can be closed to shut off the hole should a blowout threaten.

BOPBLOWOUT PREVENTER (BOP) – The equipment installed at the wellhead for the purpose of controlling pressures in the annular space between the casing and drill pipe (or tubing) during drilling, completion and certain workover operations.

BLOWOUT PREVENTER – A device attached to the casinghead that allows the well to be sealed to confine the well fluids in the wellbore.
OR  A device attached to the wellhead that allows the well to be sealed with or without a string of pipe or wireline in the wellbore.

BLOWOUT PREVENTER AND PLATFORM (BOP) – Equipment installed at the surface, below the drilling floor on land and platform rigs and on the seafloor of floating offshore rigs to prevent the escape of pressure either in the annular space between the casing and drill pipe or in an open hole during drilling and completion operations. Also used during some workover operations.

BLOWOUT PREVENTER, ANNULAR TYPE – A device which can form a seal in the annular space around any object in the wellbore or upon itself. Compression of a reinforced elastomer packing element by hydraulic pressure effects the seal.

BLOWOUT PREVENTER DRILL – A training procedure to determine that rig crews are familiar with correct operating practices to be followed in the use of blowout prevention equipment. A “dry run” of blowout preventive action.

see Oilfield Terminology Part 2


Resources:

1. Glossary of Oilfield Production Terminology.
2. Glossary of Oilfield Terms.