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Casing While Drilling

Directional Casing while Drilling.

Enhanced Casing Installation (ECI) is a Retrievable Casing while Drilling (RCwD) system enables the use of a directional drilling assembly securely locked onto the end of the casing string, to be used to drill and case the section simultaneously and retrieved back to surface upon completion of the section.

The ECI system consists of a Lock down Device that secures the BHA to the casing string and allows for the use of a short drilling assembly, including a compact under reamer placed directly above the bit. The use of composite ‘see-through’ casing joints allows for MWD and basic LWD tools to be placed inside the casing instead of below, resulting in the minimum of BHA ‘stick- out’.

This results in optimal and consistent directional drilling performance thanks to the excellent stabilization and weight transfer when using casing instead of drill pipe to drill. Steerable mud motor assemblies or more advanced drilling assemblies can be used depending on the application. Upon reaching final casing depth.