Profilforming

摘要

A drilling method comprises advancing a drill string through a cased section of a wellbore. The drill string comprises an expandable tubular, a drill assembly having a drill bit, and a tubing expander. The expandable tubular is advanced through the wellbore below the cased section, and at least a portion of the expandable tubular is expanded into the drilled wellbore using the expander. The expandable tubular does not overlap the cased section of the wellbore.