- Settore: Oil & gas
- Number of terms: 8814
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The pressure exerted by a vapor escaping from a liquid. It quantifies the tendency of molecules to enter the gaseous phase. The vapor pressure of water increases as temperature increases and reaches one atmosphere pressure (760 mm Hg or 14. 7 psia) at the boiling point (100掳C or 212掳F). The activity of an aqueous solution is the ratio of vapor pressures: a<sub>w</sub> = p/p<sub>o</sub>, where p = vapor pressure of a solution and p<sub>o</sub> is vapor pressure of pure water. Since this is a ratio of vapor pressures, activity is not a strong function of temperature.
Industry:Oil & gas
The portion of the wellbore that has had metal casing placed and cemented to protect the openhole from fluids, pressures, wellbore stability problems or a combination of these.
Industry:Oil & gas
The planned end of the well, measured by the length of pipe required to reach the bottom.
Industry:Oil & gas
The portion of the drillstring that cannot be rotated or moved vertically.
Industry:Oil & gas
The place where mud additives are kept at the rig, also known as the sack room.
Industry:Oil & gas
The permanently frozen subsoil that lies below the upper layer (the upper several inches to feet) of soil in arctic regions.
Industry:Oil & gas
The particle size that has a specified chance of being removed by an item of solids control equipment. Most commonly, D<sub>10</sub>, D<sub>50</sub> and D<sub>90</sub> cut points are specified corresponding to 10, 50 and 90% chances of removal, respectively. Taken together, they approximate the separation curve. If the percent is not specified, it is normally taken to be the D<sub>50</sub> value. For example, if the D<sub>50</sub> of a shaker screen is 100 microns, then a particle of this size has an equal chance of being removed or staying in the system. Larger particles are more likely to be removed and smaller ones more likely to be retained in the underflow.
Industry:Oil & gas
The particle size or fineness of a cement in cm<sup>2</sup>/g or m<sup>2</sup>/kg, usually determined from air permeability tests using a device known as a Blaine permeameter. Fineness affects the hydration rate (setting) and the requirements for the amounts of water, retarder and dispersant.
Industry:Oil & gas
The part of the bit that includes a hole or opening for drilling fluid to exit. The hole is usually small (around 0. 25 in. In diameter) and the pressure of the fluid inside the bit is usually high, leading to a high exit velocity through the nozzles that creates a high-velocity jet below the nozzles. This high-velocity jet of fluid cleans both the bit teeth and the bottom of the hole. The sizes of the nozzles are usually measured in 1/32-in. Increments (although some are recorded in millimeters), are always reported in "thirty-seconds" of size (i.e., fractional denominators are not reduced), and usually range from 6/32 to 32/32.
Industry:Oil & gas
Formerly known as PARCOM. The commission is a group of experts who advise North Sea countries on environmental policy and legislation. OSPAR has been influential in establishing North Sea legislation on drilling fluids that has served as the model for other operating areas. OSPAR has published lists of environmentally acceptable and unacceptable products, referred to as the "green," "grey" and "black" lists. The Green or A list consists of products posing relatively little harm to the environment (specifically the marine environment). Examples include inert minerals such as bentonite, inorganic salts that are common constituents of seawater such as sodium and potassium chloride, and simple organic products such as starch and carboxymethylcellulose (CMC). The Grey List consists of products 'requiring strong regulatory control' and includes heavy metals such as zinc, lead and chromium. The Black list covers products considered unsuitable for discharge and includes mercury, cadmium and 'persistent oils and hydrocarbons of a petroleum origin. ' The inclusion of hydrocarbons in the black list has been the driving force behind the reduction of oil discharges in the North Sea and elsewhere and has serious implications for the use of oil and synthetic fluids.
Industry:Oil & gas
