Control of well pipe rotation and advancement

Claim 1

FOR USE IN THE METHOD OF RAPIDLY ACCLERATING A PIPE STRING STUCK IN A WELL, MEANS BY AND THROUGH WHICH ROTATION IS TRANSMISSIBLE FOR FORWARDLY ROTATING THE PIPE AT THE WELL HEAD TO TWIST AND PLACE THE STRING IN TORSION WITHIN THE WELL WITHOUT RESTRICTING VERTICAL MOVEMENT OF THE STRING, SAID MEANS INCLUDING A COUPLING RELEASABLE TO ALLOW COUNTER ROTATION OF THE PIPE AT THE WELL HEAD SUBSTANTIALLY FASTER THAN FORWARD ROTATION WHEREBY THE PIPE STRING MAY BE CAUSED TO UNTWIST RAPIDALY AT DIFFERENT DEPTHS IN THE WELL, AND ACTUATOR APPARATUS FREE OF THE STRING FOR EXERTING LOADING YIELDABLY OPPOSING SAID RELEASING OF THE COUPLING, SAID ACTUATOR APPARATUS INCLUDING A FORCE ADJUSTING DEVICE FOR VARYING SAID LOADING TO THE APPLIED FOR OPPOSING SAID COUPLING RELEASE, SAID COUPLING COPRISING SPLIT SECTIONS SIZED FOR ASSEMBLY ABOUT THE PIPE AT THE WELL HEAD AND IN TORQUE TRANSMITTING RELATION THEREWITH.