دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: (PTO) a gearbox or other device that serves to relay the power of a prime mover to auxiliary equipment.

a solid material that drops out of an over saturated solution. Usually driven by an upset of equilibrium.

n: 1. an injection of water prior to chemical flooding that is used to induce reservoir conditions favorable to the surfactant solution by adjusting reservoir salinity and reducing ion concentrations. A preflush may also be used to obtain advance information on reservoir flow patterns. 2. fluid injected prior to the acid solution pumped into a well in an acid-stimulation treatment;sometimes called a spearhead. Compare overflush.

n: in pipeline construction, the process of heating pipe ends before welding. Preheating is usually necessary in areas where ambient temperatures are below 40�F (4 �C) or where there is overnight condensation of moisture on the pipe. Wagon- wheel heaters are used for preheating.

n: a coring process in which nitrogen is used to maintain a pressure of 5,000 to 7,000 pounds per square inch (34.5 to 48.3 megapascals) on the core as it is retrieved from the borehole. Pressure coring is used to minimize the escape of fluid from the core during recovery and to prevent mud invasion and flushing.

n: sww core drilling with keeping formation pressure.

n: the method of producing a gas reservoir that is not associated with a water drive. Gas is removed and reservoir pressure declines until all the recoverable gas has been expelled.

a method of producing a reservoir when water drive is not available. Also a condition that exists when the gas pressure is drawn down before the oil is recovered.

n: the use of waterflooding or gas injection to provide additional formation pressure to supplement and to conserve natural reservoir drives. Although commonly begun during primary production, pressure maintenance is a form of improved recovery. See improved recovery, secondary recovery.

n: the efforts made to maintain reservoir drive at efficient levels for maximum recovery of oil and gas. Pressure management involves controlled production rates based on the daily rate of withdrawal and monthly production al- lowed for each well and takes into account any pressure maintenance methods in use.

n: through education and practice, the well staff can familiar to handling the preventer and properly treating the overflow.

n: a textile-covered fuse with a core of very high explosive.