Patent ID: 6474419
Filing Date: 2002-11-05
Classification: E21B

Abstract:
A retrievable packer apparatus for isolating a subsurface formation intersected by a wellbore, the packer apparatus comprising:a packer mandrel adapted to be connected in a work string and lowered into the wellbore, the packer mandrel defining a longitudinal opening therethrough; a drag sleeve disposed about the packer mandrel, the drag sleeve being slidable relative to the packer mandrel; an expandable packer element disposed about the packer mandrel, the packer apparatus having a set position wherein the packer element seals the wellbore and an unset position wherein the packer element does not seal the wellbore, wherein the packer apparatus may be alternated in the wellbore between the set and unset positions; and an equalizing valve connected to a lower end of the drag sleeve and extending upwardly therefrom into the packer mandrel, the equalizing valve having an open position and a closed position, wherein in the closed position the equalizing valve seals the longitudinal opening to prevent communication through the packer mandrel so that a portion of the wellbore above the packer element will be isolated from a portion of the wellbore below the packer element when the packer apparatus is in the set position, and wherein the portion of the wellbore above the packer element may be communicated with the portion of the wellbore below the packer element through the packer mandrel when the equalizing valve is in the open position so that the pressure above and below the packer element is equalized; wherein the packer mandrel may be moved vertically relative to the drag sleeve to move the equalizing valve between the open and closed positions.