Well bore testing and pressuring apparatus

Claim 1

IN APPARATUS FOR TESTING A WELL BORE AND ADAPTED TO BE SECURED TO A TUBULAR STRING EXTENDING TO THE TOP OF THE WELL BORE: A WELL PACKER ADAPTED TO BE ANCHORED IN THE WELL BORE AGAINST UPWARD AND DOWNWARD MOVEMENT THEREWITHIN AND HAVING A FLUID PASSAGE; A TESTER VALVE ABOVE SAID CONNECTED TO SAID PACKER AND COMMUNICABLE WITH SAID PACKER PASSAGE, SAID TESTER VALVE BEING SHIFTABLE BETWEEN OPENED AND CLOSED CONDITIONS TO SELECTIVELY PERMIT FLUID TO FLOW FROM SAID PACKER PASSAGE THROUGH SAID VALVE OR PREVENT SUCH FLOW; AND SAID TESTER VALVE INCLUDING A PORTION DETACHABLY SECURED IN SAID TESTER VALVE AND REMOVABLE THEREFROM THROUGH THE TUBULAR STRING TO PROVIDE A SUBSTANTIALLY UNOBSTRUCTED PASSAGE THROUGH SAID TESTER VALVE; AN UNLOADER VALVE ABOVE AND CONNECTED TO SAID TESTER VALVE AND ADAPTED TO BE ATTACHED TO THE TUBULAR STRING, SAID UNLOADER VALVE BEING SHIFTABLE BETWEEN OPENED AND CLOSED CONDITIONS TO SELECTIVELY PERMIT FLUID TO FLOW BETWEEN THE INTERIOR OF SAID UNLOADER VALVE AND THE ANNULUS SURROUNDING THE TUBULAR STRING OR TO PREVENT SUCH FLOW, SAID UNLOADER VALVE HAVING A PASSAGE THROUGH WHICH SAID TESTER VALVE PORTION CAN MOVE.