Creating zonal isolation between the interior and exterior of a well system

摘要

A method is provided for creating a zonal isolation between the exterior and interior of an uncased section of an underground well system which is located adjacent to a well section in which a well casing is present. The method comprises inserting an expandable tubular through the existing well casing into an uncased section, such as a lateral branch, of the underground well system and subsequently expanding the expandable tubular such that said one end is pressed towards the wall of the uncased section of the well system and the outer surface of said other end is pressed against the inner surface of the well casing thereby creating an interference fit capable of achieving a shear bond and a hydraulic seal between said surrounding surfaces.