دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

abbr: equivalent circulating density. ecology n: science of the relationships between organisms and their environment.

equivalent circulating density.

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: drilling in which the size of the hole is smaller than the conventional hole diameter for a given depth. This decrease in hole size enables the operator to run smaller casing, thereby lessening the cost of completion. See miniaturized completion.

n: by current industry definition, is one where the well is TDd in 4 1/2 or smaller hole size. Slim hole drilling brings significant cost and enviromental benefits but makes well control more diffcult due to the high ECDs and small annular capacities.