Patent ID: 7168495
Filing Date: 2007-01-30
Classification: E21B

Abstract:
1. A casing-engaging wellhead isolation tool for isolating a wellhead of a cased well from high pressure well stimulation fluids, comprising: a mandrel that is stroked through the wellhead; and a releasable packer assembly connected to a bottom end of the mandrel, the releasable packer assembly being settable in a set position in which internal mechanisms of the releasable packer assembly cause casing-gripping slips to be forced outwardly into contact with a well casing so that the packer slips grip the casing after the wellhead isolation tool is stroked through the wellhead to a set position, to transfer lift pressure induced by well stimulation fluids to a casing of the cased well, so that wellhead components to which the wellhead isolation tool is mounted are not subjected to lift pressures that could exceed a holding or tensile strength of any component of the wellhead.