Apparatus for automatically filling conduit strings

Claim 1

IN WELL APPARATUS: A TUBULAR MEMBER HAVING MEANS THEREON FOR SECURING SAID MEMBER IN A CONDUIT STRING TO BE LOWERED IN A WELL BORE; BODY MEANS IN SAID TUBULAR MEMBER PROVIDING A CENTRAL FLUID PASSAGE IN SAID MEMBER, SAID BODY MEANS HAVING AN UPPER VALVE SEAT AND A LOWER VALVE SEAT, BOTH SURROUNDING SAID PASSAGE; A VALVE ELEMENT MOVABLE UPWARDLY INTO ENGAGEMENT WITH SAID LOWER VALVE SEAT TO PREVENT UPWARD FLOW OF FLUID THROUGH SAID CENTRAL PASSAGE; SAID BODY MEANS HAVING A BY-PASS PASSAGE AROUND SAID VALVE ELEMENT THROUGH WHICH FLUID CAN FLOW WHEN SAID ELEMENTS ENGAGES SAID LOWER SEAT; A TUBULAR VALVE MEMBER IN SAID TUBLAR MEMBER MOVABLE DOWNWARDLY INTO ENGAGEMENT WITH SAID UPPER SEAT TO PREVENT UPWARD FLOW OF FLUID THROUGH SAID BY-PASS PASSAGE AND THROUGH SAID TUBULAR MEMBER, SAID TUBULAR VALVE MEMBER BEING MOVABLE UPWARDLY FROM ENGAGEMENT WITH SAID UPPER SEAT TO OPEN SAID BY-PASS PASSAGE, SAID TUBULAR VALVE MEMBER ENABLING FLUID TO BE PUMPED DOWNWARDLY INTO SAID TUBULAR MEMBER FOR DOWNWARD PASSAGE THROUGH SAID TUBULAR VALVE MEMBER AND CENTRAL PASSAGE AND SHIFTING SAID VALVE ELEMENT FROM SAID LOWER SEAT; BACK PRESSURE VALVE MEANS IN SAID TUBULAR MEMBER PERMITTING DOWNWARD FLOW OF FLUID IN SAID TUBULAR MEMBER AND SHAFTABLE TO A CLOSED POSITION PREVENTING UPWARD FLOW OF FLUID IN SAID TUBULAR MEMBER; MEANS FOR PREVENTING SAID BACK PRESSURE VALVE MEANS FROM BEING SHIFTED TO CLOSED POSITION; SAID PREVENTING MEANS HAVING AN OUTWARDLY SWEDGABLE TRIP VALVE SEAT; TRIP MEANS ENGAGEABLE WITH SAID TRIP VALVE SEAT AND RESPONSIVE TO FLUID PRESSURE IN SAID TUBULAR MEMBER TO SHIFT SAID PREVENTING MEANS DOWNWARDLY IN SAID TUBULAR MEMBER TO A POSITION PERMITTING CLOSING OF SAID BACK PRESSURE VALVE MEANS; SAID TRIP MEANS RESPONSIVE TO FLUID PRESSURE IN SAID TUBULAR MEMBER TO SWEDGE SAID TRIP VALVE SEAT OUTWARDLY AND ENABLE SAID TRIP MEANS TO PASS DOWNWARDLY THROUGH SAID TRIP VALVE SEAT, TUBULAR VALVE MEMBER, CENTRAL PASSAGE AND FROM SAID TUBULAR MEMBER FOLLOWING RELEASE OF SAID PREVENTING MEANS FROM SAID BACK PRESSURE VALVE MEANS.