دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: one of usually two, three, or more mud tanks that holds drilling mud that is being circulated into a borehole during drilling. They are called active tanks because they hold mud that is currently being circulated.

n: 1. in general, a substance added in small amounts to a larger amount of another substance to change some characteristic of the latter. In the oil industry, additives are used in lubricating oil, fuel, drilling mud, and cement. 2. in cementing, a substance added to cement to change its characteristics to satisfy specific conditions in die well. A cement additive may work as an accelerator, retarder, dispersant, or other reactant.

n: The agent put into the drilling fluid in order to change some performances of the drilling fluid or slurry.

a compound incorporated into a gas, liquid, or solid system to alter the properties for a particular purpose.

n: a motor-driven paddle or blade used to mix the liquids and solids in drilling mud.

n: A mechanically driven impeller used to stir the drilling fluid to assist in the suspension of solids, blending of additives, and maintenance of uniform consistency.

n: a method of rotary drilling that uses compressed air as the circulation medium. The conventional method of removing cuttings from the wellbore is to use a flow of water or drilling mud. Compressed air removes the cuttings with equal or greater efficiency. The rate of penetration is usually increased considerably when air drilling is used;however, a principal problem in air drilling is the penetration of formations containing water, since the entry of water into the system reduces the ability of the air to remove the cuttings.

n: A method of rotary drilling that uses compressed air as the circulating medium.

drilling with air instead of drilling mud (requires diverters at the surface to handle cuttings and formation fluids).

n: in drilling operations, gas that returns to the surface with the drilling mud in measurable quantities but does not cause a kick. Increases in background gas may indicate that the well is about to kick or has kicked.

n: see Buys-Ballots law. barite n: barium sulphate, BaSO4;a mineral frequently used to increase the weight or density of drilling mud. Its relative density is 4.2 (i.e., it is 4.2 times denser than water). See barium sulphate, mud.

One of the many forms of the barium sulfate mineral. The BaSO4 material is used in drilling mud as a weighting agent and can produce a slurry of over 20 lb/gal in water.

a clay-based drilling mud gelling agent.

n: a colloidal clay, composed primarily of montmorillonite, that swells when wet. Because of its gel-forming properties, bentonite is a major component of waterbase drilling muds. See gel, mud.

a reference to colloidal clay (generally montmorillinite or smectite),generates plastic viscosity due to clay behavior, size and electrostatic layer. A slurry of which used for P&A Purposes will weigh no less than 9 ppg.

n: a device made up in the drill stem above the mill to collect bits of junk ground away during a milling operation. During milling, drilling mud under high pressure forces bits of junk up the narrow space between the boot sub and hole wall. When the junk reaches the wider annulus above the boot sub and pressure drops slightly, the junk falls into the boot sub. A boot sub also can be run above the bit during routine drilling to collect small pieces of junk that may damage the bit or interfere with its operation. Also called a junk sub or junk boot.

a device run in the drill string just above the mill to catch cuttings.