Pipe hangers for wells

Claim 1

A WELL TOOL INCLUDING: HANGER MEANS ADAPTED TO BE CONNECTED TO A WELL CASING AND HAVING A LONGITUDINAL BORE, SAID HANGER MEANS HAVING MEANS THEREIN PROVIDING AN UPWARDLY FACING SHOULDER IN SAID BORE; A TUBING HANGER HAVING EXTERNAL SHOULDER MEANS THEREON PROVIDING AN EXTERNAL SUPPORT FOR ENGAGEMENT WITH SAID UPWARDLY FACING SHOULDER IN SAID HANGER MEANS; SAID TUBING HANGER HAVING A LONGITUDINAL BORE THERETHROUGH; AN INNER TUBULAR MEMBER IN SAID TUBING HANGER BORE, AND SLIDABLE LONGITUDINALLY IN SAID TUBING HANGER BORE BETWEEN A FIRST POSITION AND A SECOND POSITION; FIRST MEANS ON SAID INNER MEMBER AND SAID TUBING HANGER COENGAGEABLE WHEN SAID INNER MEMBER IS IN SAID FIRST POSITION IN SAID TUBING HANGER TO HOLD SAID INNER MEMBER IN SAID FIRST POSITION; SECOND MEANS ON SAID INNER MEMBER AND SAID TUBING HANGER COENGAGEABLE WHEN SAID INNER MEMBER IS IN SAID SECOND POSITION IN SAID TUBING HANGER TO HOLD SAID INNER MEMBER IN SAID SECOND POSITION, SAID INNER MEMBER BEING MOVABLE BETWEEN SAID FIRST AND SAID SECOND POSITIONS WHEN SAID FIRST MEANS AND SAID SECOND MEANS ARE RELEASED TO PERMIT MOVEMENT OF SAID INNER MEMBER RELATIVE TO SAID TUBING HANGER, LONGITUDINAL MOVEMENT OF SAID INNER MEMBER BEING LIMITED TO MOVEMENT BETWEEN SAID FIRST AND SAID SECOND POSITIONS; AND HOLD-DOWN MEANS IN SAID HANGER MEANS AND RELEASABLY LOCKED IN POSITION IN SAID HANGER MEANS, SAID HOLD-DOWN MEANS HAVING MEANS ENGAGING AND RELEASABLY HOLDING SAID TUBING HANGER IN SAID HANGER MEANS AGAINST UPWARD MOVEMENT THEREIN.