METHOD AND APPARATUS FOR FORMING AN ANNULAR BARRIER IN A WELLBORE
In accordance with the present invention, an apparatus and method are provided which utilize an expandable media (100) to create an annular barrier in a subterranean well (20). The apparatus comprises a tubing assembly (10) for placement in the wellbore, the tubing assembly having an outer surface (52) creating an annular space (54) with the wellbore when the tubing assembly is placed in the wellbore. The apparatus has an expandable media assembly having an expandable material (102). The expandable material is initially in a run-in position and is capable of increasing in volume to a set position in the wellbore thereby creating an annular barrier blocking fluid flow along the annular space. The expandable material can be a foam, gel, or alloy. The media can be deformable upon enlargement and conform to the wellbore wall. The media can be a sleeve secured to the tubular assembly or a medium carried in a pressurized canister (116) for release at a selected location downhole. The expandable material can be held in the run-in position by a restraint (110), if necessary. The media can be thermally, chemically or otherwise activated to expand and can be used in conjunction with radially expandable screen assemblies and tubing assemblies.