Patent ID: 7453265
Filing Date: 2008-11-18
Classification: E21B,G01F,G01V,Y02A

Abstract:
1. A device for monitoring the position of an oil/water contact between an oil-continuous fluid overlying a water-continuous fluid within a casing pipe in a production well, the device comprising: a transmitter for generating an electromagnetic signal (S a voltage signal generator for providing electrical energy (G an insulated conductive wire extending down through said oil-water contact and near an inward facing wall of said casing pipe, said insulated conductive wire constituting a waveguide for a transverse-electric field (E said transmitter being arranged within said oil-continuous fluid and above said oil-water contact to impose said transverse-electric field on said insulated conductive wire, said conductive wire constituting a waveguide for said transverse-electric field along a two-way path for the electromagnetic signals propagating downwards and reflected signals (S a sensor arranged within said oil-continuous fluid and above said oil-water contact and within said casing pipe, said sensor being operable to detect said reflected signals; a receiver operable to receive sensor signals (R an analyzing device operable analyze said sensor signals, forwarded from said receiver, with respect to two-way propagation time or amplitude in order to calculate an elevation level for said oil-water contact within said casing pipe.