دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: The phenomenon that the cutting capacity decreases or vanishes due to abrasion, shattering, clipping, fall-out or burnout of diamond in the using process of diamond bit.

n: part of a diaphragm meter that regulates the length of the diaphragm stroke;used to adjust the volumetric displacement.

n: the value of dielectricity assigned to a substance. A substance that is a good insulator has a high dielectric constant, whereas a poor insulator has a low one. The dielectric constant of oil is lower than that of water, and on this principle a net-oil computer operates. die nipple n: a device similar to a die collar but with external threads.

n: the power supplied to a drilling rig by diesel engines driving electric generators;used widely. dieselelectric rig n: see electric rig. diesel engine n: a high-compression, internal-combustion engine used extensively for powering drilling rigs. In a diesel engine, air is drawn into the cylinders and compressed to very high pressures;ignition occurs as fuel is injected into the compressed and heated air. Combustion takes place within the cylinder above the piston, and expansion of the combustion products imparts power to the piston.

n: 1. the difference in quantity or degree between two measurements or units. For example, the pressure differential across a choke is the variation between the pressure on one side and that on the other. 2. the value or volume payment accompanying an exchange of oil for oil. The payment serves as compensation for quality, location, or gravity differences between the oils being exchanged.

n: The decks of vibrosieve with different angle in the same screen frame

n: a specialpurpose valve used to facilitate spacing out and flanging up the well, run in on the tubing string.

n: a device installed near the bottom of the casing. It has a valve that keeps mud out of the casing so that the casing can be floated into the hole to lessen the weight on the rigs equipment This valve will, however, automatically open to let mud into the casing when the pressure of the mud outside the casing becomes high enough to collapse the joints of casing near the bottom of the string. Thus, this special collar, with its pressure-sensitive valve, not only allows casing to float, but also keeps it from collapsing.

n: the extent of variation between the lowest and highest differential pressures that an orifice meter can accurately measure.