Abstract: The invention comprises a uniquely shaped sealing element or elements for a packer. In an application using a stack of elements, the upper element is configured so that at least a portion of its inside diameter represents an interference fit with the mandrel onto which it is mounted. A built-in moment within the packing element occurs as a result of the partial interference fit. Additionally, a taper is provided which, in effect, shifts the point of contact of the upper element closer to a central element, tending to better give extrusion support to the central element. The taper also facilitates the creation of a resistive moment which fights the tendency of the upper element to extrude in the upper outermost corner of the upper element, for example. The central element can also be installed on a mandrel with interference throughout its length to create a built-in radial force urging the element back into its original shape after it is expanded and allowed to relax.

Abstract: A retrievable whipstock/anchor assembly is used to allow drilling of additional wellbores from an original or primary wellbore (which may be a highly deviated or horizontal open wellbore). The retrievable whipstock assembly is comprised primarily of two sections, an anchor section and a whip stock section. The anchor section provides resistance to compression and rotation forces, and provides rigidity for the whipstock. The whipstock provides a support face for drilling the additional wellbores. The whipstock can be oriented radially to allow drilling at any radial angle, and can be set at any depth. Anchoring of the retrievable whipstock assembly is provided by means of an inflatable element which expands to grip the inside wall of the wellbore. Radial orientation can be provided by rotating the retrievable whipstock assembly from surface or other means until the whipstock is at the desired orientation.

Abstract: An expendable plug is shown for use in a well bore tool for controlling the flow of well bore fluids from a production zone to the well surface. The plug is located within a tubular housing which is made up in a well tubing string having an internal bore with a predetermined minimum internal diameter. The plug initially closes off the internal bore of the tubing string at a selected location. An actuator is triggered by an appropriate signal to expend the plug of expendable material, and to remove the plug from the internal bore of the tubing string, whereby fluids in the surrounding earthen formation are allowed to flow up the tubing string to the well surface.