Abstract: The invention provides an apparatus for actuating a downhole tool by utilizing a pressure differential created by fluid flowing through a conduit. The conduit is in communication with a pressure sensing line that is selectively exposable to areas of the conduit having different pressures. By exposing the pressure sensing line to a portion of the conduit having a predetermined pressure therein, the pressure sensing line causes actuation of a hydraulic tool therebelow.

Abstract: A plurality of packing elements are mounted in vertically spaced relationship on a tubing string with the spacing of the elements corresponding generally to the spacing of a plurality of sets of perforations in a well conduit. The lowermost packing unit is provided with radially expanding locking elements which engage a locking groove provided in the well conduit. All packing units incorporate expandable elastomeric sealing members and are set by the application of tension to the tubing string and are unset by the subsequent application of a higher degree of tension to the tubing string.

Abstract: A plurality of packing elements are mounted in vertically spaced relationship on a tubing string with the spacing of the elements corresponding generally to the spacing of a plurality of sets of perforations in a well conduit. The lowermost packing unit is provided with radially expanding locking elements which engage a locking groove provided in the wall conduit. All packing units incorporate expandable elastomeric sealing members and are set by the application of tension to the tubing string and are unset by the subsequent application of a higher degree of tension to the tubing string.

Abstract: A plurality of packing elements are mounted in vertically spaced relationship on a tubing string with the spacing of the elements corresponding generally to the spacing of a plurality of sets of perforations in a well conduit. The lowermost packing unit is provided with radially expanding locking elements which engage a locking groove provided in the well conduit. All packing units incorporate expandable elastomeric sealing members and are set by the application of tension to the tubing string and are unset by the subsequent application of a higher degree of tension to the tubing string.

Abstract: A packer apparatus for use in a subterranean well comprises an inner mandrel and means for applying tension to the inner mandrel to set radially expandable slips and packing elements. The mandrel can be releasably positioned in a first position to secure the slips and packing element in the retracted position and can be shifted to a second position in which engagable lock segments secure the slips and packing element in expanded configuration. The packer can be released by rotational manipulation or by axial force. The packer apparatus can be used with rotationally manipulatable well tools positioned either above or below the packer apparatus.