They give positive indication that cement will be set in the correct place before latching at the bottom of the work string using a pre-installed landing sub. Once secure, pump pressure inflates the elastomer to seal the wellbore. CXT-IST is then released by picking up the work string.
The tools create a 100% wall-to-wall base for well fluid or cement. Operators can deploy as many ISTs as needed in the same or multiple zones without tripping drill pipe in-and-out of a hole.
In 2012 IST's maker was winner of the New Idea category at the Offshore Achievement Awards. Since then, the product has undergone extensive field trials in the UK with reported excellent customer response.