Well construction without dedicated casing runs
Casing while drilling (CwD) eliminates classic casing runs and isolates formations while drilling. Drilling and casing are executed simultaneously, section by section.
Odfjell Well Services' casing running tool, the TDCRTi, is the cornerstone of casing while drilling. When the casing is run with top drive and TDCRTi, you operate the casing string much in the same manner as a drill string. The TDCRTi lets you push, pull, rotate and reciprocate, thus giving you extended control over the string.
CwD Maximizes efficiency
The smearing effect is a side effect very desirable and almost always achievable when Casing While Drilling. A more circular, gauged wellbore can be obtained due to smearing or "smoothing" motion of the casing string, since the annular clearance is much smaller compared to conventional drilling.
The smaller annulus requires less cement and has less cement excess compared to conventional drilling. More than 20 percent savings on cement excess compared to conventional drilling may be obtained.