دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

a deliberate shut off of a zone by a downhole valve or other method, to prevent cross flow.

n: signals transmitted from an instrument located downhole to a receiving monitor on the surface-a surfacereadout instrument. Downhole telemetry may be transmitted via a special wireline or via mud pulse (much as radio signals are transmitted through the air). Frequently, downhole telemetry is employed in determining the drift angle and direction of a deviated wellbore. See measurement while drilling.

n: The process whereby signals are transmitted from a downhole sensor to a surface readout instrument. This can be done by a conductor line (as on steering tools) or by mud pulses (as in MWD tools (q.v.)).

n: refer to vibration dampender

n: the join with a symmetric cataclinal egress bit on both sides respectively, connected to the bit and

n: 1. the vertical distance between the bottom of a vessel floating in water and the waterline. 2. a written order drawn on a solvent bank that authorizes payment or a specified sum of money for a specific purpose to a named person. A draft mayor may not be negotiable, depending on how it is drawn up. Also called bank draft.

n: any of a variety of drilling bits that have no moving parts. As they are rotated on bottom, elements of the bit make hole by being pressed into the formation and being dragged across it. See fishtail bit.

n: A drilling bit that has no cones or bearings but consists of a single unit with a cutting structure and circulation passageways. The fishtail bit was an early example of a drag bit, but is no longer in common use. Diamond bits are also drag bits.

n: in tank sampling, a sample obtained from the draw-off or discharge valve.

n: clause in a gas sales contract that states that the pipeline company will attempt to take sufficient volume to prevent the seller from being drained.

n: Small-diameter horizontal wells drilled into a formation from a vertical borehole or shaft.