US Patent 10385640 Tension cutting casing and wellhead retrieval system

An apparatus for use in a well includes a tubular mandrel configured to connect to a downhole assembly. An outer hub is configured to attach to a wellhead and has a bore therethrough. An inner housing is disposed on the tubular mandrel and configured to attach the outer hub to the wellhead. A clutch assembly is disposed within the bore of the outer hub and movable between a locked position and an unlocked position, wherein the tubular mandrel is rotatable relative to the inner housing to operate the downhole assembly in the unlocked position.