Patent ID: 8757275
Filing Date: 2014-06-24
Classification: E21B

Abstract:
1. An apparatus for isolating a first zone from a second zone in a subterranean wellbore, the apparatus comprising: an outer tubular and an inner tubular disposed within the outer tubular forming a substantially annular flow path therebetween that is in fluid communication with the first zone, the inner tubular defining a central flow path therein that is in fluid communication with the second zone, the outer tubular including an extension that forms a substantially annular pocket; a sleeve having at least one seal disposed on an inner surface thereof, the sleeve positioned in the annular flow path to control fluid flow therethrough, the sleeve axially movable relative to the outer tubular and the inner tubular between a closed position wherein the seal engages an outer surface of the inner tubular and an open position wherein the seal engages an outer surface of the extension of the outer tubular; and a mandrel slidably disposed within the inner tubular and coupled to the sleeve, the mandrel operable to shift the sleeve between the open position and the closed position responsive to changes in pressure within the central flow path, wherein, the mandrel and the inner tubular define an actuation chamber operable to receive pressure from within the central flow path to bias the mandrel in a first direction relative to the inner tubular and shift the sleeve from the closed position to the open position; and wherein, the mandrel includes at least one reclosing port operable to receive pressure from within the central flow path when the sleeve is in the open position to bias the mandrel in a second direction relative to the inner tubular and shift the sleeve from the open position to the closed position.