دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a mixture of individual samples from several compartments of a ship or barge, each of which contains the same grade of petroleum material. The mixture is blended in proportion to the volume of material in each compartment.

n: a directional survey that provides a record of drift angle and direction at various depths in the hole. See directional survey.

n: A technique for determining the deviation of a wellbore. The multishot tool provides more accuracy than the single-shot tool and is usually used in highly deviated wells.

n: a pin shaped like a carpenters nail and placed in a pressure relief valve. When the pin shears, it opens the valve to relieve pressure inside a vessel. Even though the nail pin is shaped like a nail, a carpenters nail should never be substituted for a nail pin. See also shear pin.

n: a volatile, flammable liquid hydrocarbon distilled from petroleum and used as a solvent or a fuel.

an aromatic solvent with highly-variable quality. Often has a described carbon range in the C7 to C10 area.

n: a crude oil that is characterised by a low API gravity and a low yield of lubricating oils and that has a low pour point and a low viscosity index (compared to paraffin-base oils). It is often called asphalt-base oil, because the residue from its distillation contains asphaltic materials but little or no paraffin wax.

n: a standard recognised by an official national decision as the basis for fixing the value. in a country. of all other standards of the given quantity. In general. the national standard in a country is also the primary standard.

n pi: clays that are encountered when drilling various formations;they mayor may not be incorporated purposely into the mud system.

n: natural clays,as opposed to commercial clays,are clays that are encountered when drilling various formations. The yield of these clays varies greatly and they may or may not be purposely incorporated into the mud system.

natural occurring clays as opposed to commercially formulated clays.

n: the open fracture that caused by the crust movation and mountain building. When meet this kinds of fracture layer, it is very easy to circulation loss.



a fracture in the rock created by geologic events such as uplift.

n: a highly compressible. highly expansible mixture of hydrocarbons with a low specific gravity and occurring naturally in a gaseous form. Besides hydrocarbon gases, natural gas may contain appreciable quantities of nitrogen. helium. carbon dioxide. hydrogen sulphide. and water vapour. Although gaseous at normal temperatures and pressures, the gases making up the mixture that is natural gas are variable in form and may be found either as gases or as liquids under suitable conditions of temperature and pressure.

n: A naturally occurring mixture of hydrocarbon gases that is highly compressible and expansible. Methane [CH4] is the chief constituent of most natural gas (constituting as much as 85% of some natural gases),with lesser amounts of ethane [C2H6], propane [C

methane, CH4;plus some short chain hydrocarbons (ethane, propane, butane) that may be in gasseous state at standard conditions.