Patent ID: 7762338

Claim:
A subsea well apparatus, comprising: a subsea wellhead assembly having a bore containing an annular recess, the bore having a diameter below the recess that is at least equal to a diameter of the bore above the recess; a riser extending from a subsea wellhead assembly to a vessel at the surface of the sea; a pipe hanger having a string of pipe suspended therefrom, which is lowered through the riser with a string of conduit and into the bore of the subsea wellhead assembly; a sensor positioned adjacent the subsea wellhead assembly, the sensor being positioned to monitor the axial position of the pipe hanger relative to the recess within the subsea wellhead assembly and to communicate the axial position of the pipe hanger to the surface; and a locking mechanism carried by the pipe hanger having a retracted position circumscribing a diameter smaller than the diameter of the bore below the recess, and a locked position in engagement with the recess to support weight of the pipe hanger and the pipe with the subsea wellhead assembly when the locking mechanism is in the locked position, the locking mechanism being selectively operable from the surface when the sensor indicates that the locking mechanism is aligned with the recess.