Apparatus for closing side openings into pipelines

Claim 1

APPARATUS FOR CLOSING A SIDE OPENING INTO A PIPELINE COMPRISING IN COMBINATION A NIPPLE ATTACHED TO THE EXTERIOR OF THE PIPELINE AROUND AN OPENING INTO THE SIDE OF THE PIPE, SAID NIPPLE HAVING A GROOVE AROUND ITS INTERIOR SUBSTANTIALLY NORMAL TO A FLOWWAY THROUGH THE NIPPLE; A PLUG, FITTING INTO THE FLOWWAY, HAVING A CENTRAL THREADED OPENING THERETHROUGH, AN ANNULAR FLUID ENERGIZED SEAL OF THE O-RING TYPE CARRIED BY AND AROUND THE PLUG IN POSITION TO SEAL BETWEEN THE SIDES OF THE PLUG AND THE INTERIOR OF THE NIPPLE AS THE PLUG IS MOVED THROUGH THE FLOWWAY IN THE NIPPLE AS WELL AS WHEN THE PLUG IS IN ITS FINAL PLUGGING POSITION IN THE FLOWWAY; SAID PLUG ALSO HAVING A FLOW PASSAGEWAY THERETHROUGH SPACED FROM THE THREADED OPENING AND INWARDLY FROM THE PERIPHERY OF THE PLUG FOR BYPASSING FLUID ACROSS THE PLUG SO AS TO EQUALIZED PRESSURES THEREACROSS; A CONTROL SCREW ENGAGING THE THREADED OPENING THROUGH THE PLUG; AND VALVE AND CAM MEANS OPERABLE, RESPONSIVE TO LONGITUDINAL TRAVEL OF THE CONTROL SCREW IN ONE DIRECTION, TO MOVE SAID RETAINING MEMBERS OUTWARDLY INTO SAID GROOVE AND TO CLOSE SAID PASSAGEWAY THROUGTH THE PLUG, AND ALSO OPERABLE, RESPONSIVE TO LONGITUDINAL TRAVEL OF THE CONTROL SCREW IN THE OPPOSITE DIRECTION, TO OPEN SAID PASSAGEWAY TO EQUALIZE PRESSURE ACROSS SAID PLUG AND TO PERMIT SAID RETAINING MEMBERS TO BE RETRACTED FROM SAID GROOVE SO THE PLUG CAN BE MOVED OUT OF SAID NIPPLE.