An Expandable Slotted Tubing, Fibre-Cement Wellbore Lining System

An expandable-slotted-tubing, fiber-cement wellbore-lining system has been developed. Its purpose is to temporarily secure the integrity of a wellbore section to allow drilling operations to continue through deeper overpressured or depleted zones. The lining is installed below the previous casing with no or minimal reduction in hole diameter. The technology makes it possible to realize major reductions in well costs by avoiding the use of certain intermediate and contingency casing strings. It also helps in high-pressure/high-temperature (HPHT) well designs where the requirement for additional casing strings may become excessive. The paper outlines the technologies involved and installation/evaluation procedures. Details are given of onshore and offshore field trials in Europe and the US.