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Oil and Gas Well Drilling and Servicing eTool
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Oil and Gas Home Glossary of Terms - A
† This is an abridged version of the Dictionary of Petroleum Terms provided by Petex and the University of Texas Austin. © Petex 2001
- abandon
- v: to temporarily or permanently cease production from a well or to cease further drilling operations.
- abnormal pressure
- n: pressure outside the normal or expected range.
- abrasion
- n: wearing away by friction.
- accumulator
- n: the storage device for nitrogen pressurized hydraulic fluid, which is used in operating the blowout preventers.
- acetic acid
- n: an organic acid compound sometimes used to acidize oilwells.
- acid fracture
- v: to part or open fractures in limestone formations by using fluid under hydraulic pressure.
- acidize
- v: to treat formations with acid for the purpose of increasing production.
- acid stimulation
- n: a well stimulation method using acid. See acidize.
- aeration
- n: the introduction of air or gas into a liquid.
- AESC Association of Energy Service Companies
- n: a trade association that represents the interests of members of the energy service segment of the oil and gas industry. It offers publications regarding recommended industry practices and training materials.
- air hoist
- n: a hoist operated by compressed air; a pneumatic hoist. Air hoists are often mounted on the rig floor and may be used to lift joints of pipe and other heavy objects.
- ANSI American National Standards Institute
- n: a non-profit organization (501(c)3) that administers and coordinates voluntary standardization and conformity assessment system.
- API American Petroleum Institute
- n: a trade association and standards organization that represents the interests of the oil and gas industry. It offers publications regarding standards, recommended practices, and other industry related information.
- annular blowout preventer
- n: a well control device, usually installed above the ram preventers, that forms a seal in the annular space between the pipe and well bore or, if no pipe is present, over the well bore itself.
- annular pressure
- n: pressure in an annular space.
- annulus
- n: the space around a pipe in a well bore, sometimes termed the annular space.
- API-monagram
- adj; the logo of the American Petroleum Institute (API) that is placed on certain pieces of oilfield equipment by the equipment manufacturer. API licenses the use of the monogram on equipment that meets the API's minimum standards. It offers publications regarding standards, recommended practices, and other industry related information. Address: 1220 L Street NW; Washington, DC 20005; (202) 682-8000
- artificial lift
- n: any method used to raise oil to the surface after a well ceases to flow.
![Accumulator](https://webarchive.library.unt.edu/web/20170124204407im_/https://www.osha.gov/SLTC/etools/oilandgas/images/accumulator2.gif)
![Acidize](https://webarchive.library.unt.edu/web/20170124204407im_/https://www.osha.gov/SLTC/etools/oilandgas/images/acidize.gif)
![Air Hoist](https://webarchive.library.unt.edu/web/20170124204407im_/https://www.osha.gov/SLTC/etools/oilandgas/images/air_hoist.gif)
Annular Blowout Preventer
A large valve, usually installed above the ram preventers, that forms a seal in the annular space between the pipe and well bore. If no pipe is present, it forms a seal on the well bore itself. See blowout preventer.†
![Annular Blowout Preventer. This illustration shows a cutaway of an Annular Blowout Preventer, with various components labeled: Head, piston, wear plate, packing unit, opening chamber, and closing chamber.](https://webarchive.library.unt.edu/web/20170124204407im_/https://www.osha.gov/SLTC/etools/oilandgas/images/annular_bops2.jpg)
#10. Blowout Preventer
One or more valves installed at the wellhead to prevent the escape of pressure either in the annular space between the casing and the drill pipe or in open hole (for example, hole with no drill pipe) during drilling or completion operations. See annular blowout preventer and ram blowout preventer.†s
![Blowout Preventer](https://webarchive.library.unt.edu/web/20170124204407im_/https://www.osha.gov/SLTC/etools/oilandgas/images/bop1_small.jpg)
#48. Ram Blowout Preventer
A blowout preventer that uses rams to seal off pressure on a hole that is with or without pipe. It is also called a ram preventer. Ram-type preventers have interchangeable ram blocks to accommodate different O.D. drill pipe, casing, or tubing.†
![Ram Blowout Preventer](https://webarchive.library.unt.edu/web/20170124204407im_/https://www.osha.gov/SLTC/etools/oilandgas/images/ram-type_bops.jpg)
![Annular Blowout Preventer. This illustration shows a cutaway of an Annular Blowout Preventer, with various components labeled: Head, piston, wear plate, packing unit, opening chamber, and closing chamber.](https://webarchive.library.unt.edu/web/20170124204407im_/https://www.osha.gov/SLTC/etools/oilandgas/thumbnails/annular_bops2.jpg)
#26. Annulus
The space around a pipe in a well bore, the outer wall of which may be the wall of either the bore hole or the casing; sometimes termed the annular space.†
![Annulus](https://webarchive.library.unt.edu/web/20170124204407im_/https://www.osha.gov/SLTC/etools/oilandgas/images/casing_annulus.jpg)
![Annulus](https://webarchive.library.unt.edu/web/20170124204407im_/https://www.osha.gov/SLTC/etools/oilandgas/thumbnails/casing_annulus.jpg)