US Patent 7784552 Liner drilling method

An installation system for installing a liner in a well includes drilling while simultaneously running the liner. A string of drill pipe with a bottom hole assembly including a drill bit on a lower end is lowered into the liner while the liner is suspended at the rig floor. The bottom hole assembly engages a lower sub of the liner for torque transmission. A running tool secured to the drill pipe engages the upper sub such that the running tool supports the weight of the liner and transmits torque. The drill pipe and liner are rotated to drill deeper into the wellbore. The liner hanger can be set to engage the casing, then released and reset at a different point.