دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a roller cone bit that is specially designed for air or gas drilling. It is very similar to a regular bit, but features screens over the bearings to protect them from clogging with cuttings and thicker hardfacing on the shirttail to protect them from abrasive, high-velocity air or gas drilling fluid.

n: The angle formed by two aspects of chisel teeth
of cone bit.

n: The assemblage opening in palm journal of cone bit. The weld line after cone ball is installed and the ball retaining plug is inserted.

n: on a roller cone bit, a coneshaped steel device from which the manufacturer either mills or forges steel teeth, or into which the manufacturer inserts tungsten carbide buttons. Most roller cone bits have three cones, which roll, or rotate, on bearings as the bit rotates. As the cones roll over the formation, the cutters on the cone scrape or gouge the formation to remove the rock.

n: The ratio between the sum of the teeth width of cone bit and the length of contact busbar wire in the downhole.

n: a condition in which the weight on a bit tooth has been so great that the tooth has dulled until its softer inner portion caves over the harder case area.

n: The tipping becomes blunt due to the teeth of cone bit suffers oversized load.

n: a drilling bit with tungsten carbide inserts on the cones that resemble plugs or buttons. See roller cone bit.

nn: The cone bit which is installed with obtuse tungsten carbide insert.

n: A method that cone bit breaks the rock. The granulitization is produced by bit load affecting to the rock. The cutting action is produced by cone rolling at the bottom.

n: see insert.

n: Usually refers to polycrystalline diamond or diamondite. Including manifold shapes, usually cylindrical. Used as the cogging of diamond bit or cone bit.

n: The heigh of tungsten carbide insert above cone surface in cone bit.