To cease work on a well which is non-productive, to plug off the well with cement plugs and salvage all recoverable equipment. Also used in the context of field abandonment.

Accumulation - Pressure increase over the maximum allowable working pressure of the vessel allowed during discharge through the pressure-relief device.

Acids are compounds that contain hydrogen. When mixed with water, the hydrogen is relased as positive ions that can bond with other substances, having a corrosive effect on them.

A combination of oil and acid or water and acid under high pressure used to separate or fracture hard limestone formations.

To treat oil-bearing limestone or other formations, using a chemical reaction with acid, to increase production. Hydrochloric acid or other acid is injected into the formation under pressure. The acid etches the rock, enlarging the pore spaces and passages through which the reservoir fluids flow. The acid is then pumped out and the well swabbed and put back into production.

Actinides - Asequence of highly radioacitve chemical elements spanning atomic numbers 89 to 103.

(Link/url to the periodic table) Opens in the same window.

Actual flow capacity is the flowing capacity determined by measurement.

Adjusted set pressure - Vacuum or gauge pressure at which under test stand conditions (atmospheric back pressure) valves commence to lift

An industrial gas turbine. The design of which is derived from aerospace turbines, generally between 10-50 megawatts.

AEx - North American NEC 505 Explosion protected Equipment.