دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: 1. the pressure at the bottom of a borehole. It is caused by the hydrostatic pressure of the wellbore fluid and, sometimes, by any back-pressure held at the surface, as when the well is shut in with blowout preventers. When mud is being circulated, bottomhole pressure is the hydrostatic pressure plus the remaining circulating pressure required to move the mud up the annulus. 2. the pressure in a well at a point opposite the producing formation, as recorded by a bottomhole pressure bomb.

n: The pressure at the bottom of the borehole, or at a point opposite the production formation.

n: a pressuretight container (bomb) used to record the pressure in a well at a point opposite the producing formation.

n: an instrument to measure bottomhole pressure. Also called bottomhole pressure bomb.

n: a test that measures the reservoir pressure of the well, obtained at a specific depth or at the midpoint of the producing zone. A flowing bottomhole pressure test measures pressure while the well continues to flow;a shut-in bottomhole pressure test measures pressure after the well has been shut in for a specified period of time. See bottomhole pressure. bottomhole pressure gauge.

n: the relatively small amount of gas enters a well when the mud pump is stopped for a connection to be made. Since bottomhole pressure decreases when the pump is stopped, gas may enter the well.

the small amount of gas that enters the wellbore when circulation is stopped to make a connection. The gas only enters the wellbore in this case when the static fluid pressure is less than the pore pressure.

n: I. the difference between static and flowing bottomhole pressures. 2. the distance between the static level and the pumping level of the fluid in the annulus of a pumping well.

the difference between two pressures. Completion drawdown is the pressure differential from the formation near the wellbore to the wellbore.

n: (ECD) the increase in bottomhole pressure expressed as an increase in pressure that occurs only when mud is being circulated. Because of friction in the annulus as the mud is pumped, bottomhole pressure is slightly, but significantly, higher than when the mud is not being pumped. ECD is calculated by dividing the annular pressure loss by 0.052, dividing that by true vertical depth, and adding the result to the mud weight Also called circulating density, mudweight equivalent

n: The effective drilling-fluid weight at any point in the annulus of the well bore during fluid circulation.ECD includes drilling-fluid density, cuttings in the annulus, and annular pressure loss.

the effective fluid density that the formation sees when the friction pressure on the fluids returning to surface is added to the fluid density.

n: a bottomhole pressure test that measures pressure while the well is flowing. See bottomhole pressure test.

n: the force exerted by fluids in a formation, recorded in the hole at the level of the formation with the well shut in. Also called reservoir pressure or shut-in bottomhole pressure.

n: the pressure exerted by the formation fluids at a particular point in the formation,sometimes called reservoir pressure or pore pressure.

the pressure of the fluid in the formation. The initial reservoir pressure is the pressure at discovery.

n: the reduction in a wells bottomhole pressure. See drawdown.