Casing hanger

Claim 1

A HANGER AND TOOL ASSEMBLY FOR USE IN LANDING AND SUSPENDING A STRING OF PIPE WITHIN A HEAD COMPRISING: A HANGER BODY HAVING A VERTICAL INNER BORE AND AN EXTERIOR DOWNWARDLY FACING SHOULDER BY WHICH THE HANGER BODY MAY BE SUSPENDED IN THE HEAD; MEANS FOR CONNECTING SAID HANGER BODY TO THE PIPE TO BE SUSPENDED; A LATERALLY DEFLECTABLE AND RESILIENT LOCKING RING CARRIED IN AN ANNULAR GROOVE IN THE EXTERIOR OF SAID HANGER BODY ABOVE SAID SHOULDER, SAID LOCKING RING HAVING AN OUTWARDLY EXTENDING FLANGE PORTION AND A BODY PORTION ABOVE SAID FLANGE PORTION, SAID LOCKING RING WHEN RELAXED ASSUMING AN EXPANDED POSITION SUCH THAT SAID FLANGE PORTION PROJECTS RADIALLY BEYOND THE CIRCUMFERENCE OF SAID HANGER BODY, SAID BODY PORTION HAVING AN EXTERIOR SURFACE WHICH IS TAPERED UPWARDLY AND INWARDLY; A TOOL BODY THREADEDLY CONNECTED TO SAID HANGER BODY; MEANS FOR CONNECTING SAID TOOL BODY TO THE LOWER END OF A LANDING CASING OR THE LIKE; A LOCKING RING COMPRESSOR COLLAR HAVING AN INNER SURFACCE TAPERED DOWNWARDLY AND OUTWARDLY TO ENGAGE SAID TAPERED SURFACE ON SAID LOCKING RING; AND MEANS CONNECTING SAID COLLOR TO SAID TOOL BODY WHEREBY UPWARD MOVEMENT OF SAID TOOL BODY OCCASIONED BY ROTATION OF SAID TOOL BODY IN A DIRECTION TO UNSCREW SAID TOOL BODY FROM SAID HANGER BODY RAISES SAID COLLAR AWAY FROM SAID LOCKING RING TO PERMIT THE LATTER TO EXPAND AND WHEREBY DOWNWARD MOVEMENT OF SAID TOOL BODY OCCASIONED BY ROTATION OF SAID TOOL BODY IN A DIRECTION TO SCREW SAID TOOL BODY ON TO SAID HANGER BODY MOVES SAID COLLAR TOWARD SAID LOCKING RING TO COMPRESS THE LATTER, SAID