دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: pressure exceeding or falling below the pressure to be expected at a given depth. Normal pressure increases approximately 0.465 pow1ds per square inch per foot of depth or 10.5 kilopascals per metre of depth. Thus, normal pressure at 1,000 feet is 465 pounds per square inch;at 1,000 metres it is 10,500 kilopascals. See pressure gradient.

n: A formation pressure that deviates from the normal formation fluid hydrostatic pressure. Such pressure may be classified as "subnormal" (lower than normal) or "overpressured" (higher than normal).

n: the force in dynes that a stationary flat plate with a surface area of 1 square centimetre exerts on a similar parallel plate 1 centimetre away and moving in its own plane with a velocity of 1 centimetre per second, the space between the plates being filled with the liquid in question. It is a measure of the resistance that the liquid offers to shear. absolute error n: the difference between the result of a measurement and the true value of the measured quantity as determined by means of a suitable standard device.

n: total pressure measured from an absolute vacuum. It equals the sum of the gauge pressure and the atmospheric pressure. Expressed in pounds per square inch.

the reading of gauge pressure plus the atmospheric pressure.

n: a bottle-shaped steel cylinder located in a blowout preventer control unit to store nitrogen and hydraulic fluid under pressure (usually at 3,(XK)pounds per square inch). The fluid is used to actuate the blowout preventer stack.

a large, load supporting formation that may serve to reduce the total overburden load on a pay zone. These formations may cover hundreds of square miles over a basin. A second use is as a semi-stable structure of sand grains around a perforation or other

n: a mobile submersible drilling structure used in arctic areas. The rig is towed onto the drilling site and submerged during periods when the water is free of ice. All equipment below the waterline is surrounded by a caisson to protect it from damage by moving ice. The drilling deck has no square comers so that moving ice can better flow around it. See submersible drilling rig.

(atm) n: a unit of pressure equal to the atmospheric pressure at sea level, 14.7 pounds per square inch (101.325 kilopascals)

n: the pressure exerted by the weight of the atmosphere. At sea level, the pressure is approximately 14.7 pounds per square inch (101.325 kilopascals),often referred to as 1 atmosphere. Also called barometric pressure.

v: to make a gift of personal property by means of a will. Compare devise. Bernoullis theorem n: a mathematical expression of the conservation of energy in streamline flow;the theorem states that the sum of the ratio of the pressure to the mass density, the product of the gravitational constant and the vertical height. and the square of the velocity divided by 2 are constant.