دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

Australian Institute of Petroleum.

American Institute of Professional Geologists.

n: a roller cone bit that is specially designed for air or gas drilling. It is very similar to a regular bit, but features screens over the bearings to protect them from clogging with cuttings and thicker hardfacing on the shirttail to protect them from abrasive, high-velocity air or gas drilling fluid.

n: The gas-holder tank connected with discharge line of reciprocal pump. It is a air cushion aerated by compressive air, used to absorb or decrease fluctuation of pressure and delivery capacity disproportion when reciprocal pump works.

n: Used compressive air which replaces flushing fluid as circulation media to cool the bit and carry over cuttings.

n: The inadvertent mechanical incorporation and dispersion of air into a drilling fluid system. See also Aeration.

n: diving in which a diver uses a normal atmospheric mixture of oxygen and nitrogen as a breathing medium. It is limited to depths less than 190 feet (58 metres) because of the dangers of nitrogen narcosis;however, dives with bottom times of 30 minutes or less may be conducted to a maximum of 220 feet (67 metres).

n: a method of rotary drilling that uses compressed air as the circulation medium. The conventional method of removing cuttings from the wellbore is to use a flow of water or drilling mud. Compressed air removes the cuttings with equal or greater efficiency. The rate of penetration is usually increased considerably when air drilling is used;however, a principal problem in air drilling is the penetration of formations containing water, since the entry of water into the system reduces the ability of the air to remove the cuttings.

n: A method of rotary drilling that uses compressed air as the circulating medium.

drilling with air instead of drilling mud (requires diverters at the surface to handle cuttings and formation fluids).