دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

a very small string, usually run along the outside of the tubing and banded to the tubing. Commonly used for hydraulic control of safety valves and sliding sleeves. May also transmit bottom hole gauge data.

n: An apparatus measuring rheological property of drill fluid. The principle is that different drilling fluid passes through different diametral pipe with different speed under pressure difference.

n: very fine particles of almost pure amorphous carbon, usually produced from gaseous or liquid hydrocarbons by thermal decomposition or by controlled combustion with a restricted air supply. It is used in the manufacture of carbon paper, tires, cosmetics, and so on.

HEC, an anionic water soluble polymer used in various fluids. Can be relatively clean breaking under the right conditions.

n: a certificate signed by vessel representatives acknowledging the amount of cargo that they intend to load. In general, most product cargoes have a tolerance based on supplier, receiver, or vessel capabilities. Each party involved with the loading agrees to the quantity to be loaded.

n: 1. steel pipe placed in an oil or gas well to prevent the wall of the hole from caving in, to prevent movement of fluids from one formation to another, and to improve the efficiency of extracting petroleum if the well is productive. A joint of casing may be 16 to 48 feet (4.8 to 14.6 metres) long and from 4.5 to 20 inches (11.4 to 50.8 centimetres) in diameter. Casing is made of many types of steel alloy, which vary in strength, corrosion resistance, and so on. 2. large pipe in which a carrier pipeline passes under railroad rights-of-way and some roads to shield the pipeline from the unusually high load stresses of a particular location. State and local regulations identify specific locations where casing is mandatory.

n: Steel pipe placed in an oil or gas well to prevent the wall of the hole in a drilled interval from caving in, as well as to prevent movement of fluids from one formation to another.


one of several strings of steel pipe in a well design that, together with cement, forms a barrier to fluid movement along the drilled hole. It is commonly at least partly cemented in the wellbore.

n: see float collar.

n: The collar with back pressure control valve, installed at the bottom of casing string. Prevents drill fluid entering into casing and decreases the weight of casing by buoyance. Also prevent cement recirculating when cementing.

n: see float shoe.

n: The Steel and round nipple with back pressure control valve, installed at the bottom of casing string. Leading casing entering into the wellbore and preventing drill fluid entering into the casing to decrease the weight of casing.

n: The casing float or non-return valve of float shoe, allowing fluid one way flowing from top to bottom through casing.