Patent ID: 8136604

Claim:
An apparatus for protecting a bore of a wellhead member comprising: a tubular adapter assembly having an inner diameter and selectively securable to the wellhead member, a sleeve having an internal passage, a first seal adapted to form a seal against the inner diameter of the tubular adapter assembly, and a second seal adapted to form a seal against an adapter coupled to an end of a length of casing; a locking mechanism adapted to secure the sleeve to the tubular adapter assembly the locking mechanism comprising an axially-movable locking member, wherein the locking mechanism is disengaged from the tubular adapter assembly when the axially-movable locking member is located in a first axial position and is engaged with the tubular adapter assembly when the axially-movable locking member is located at a second axial position and a retaining member adapted to maintain the axially-movable member in each of the first position and the second position relative to the sleeve.