THE FULL BORE SHUT-IN TOOL ASSEMBLY IS A DOWNHOLE MASTER VALVE, WHICH KEEPS THE DRILLSTRING OR TUBING DRY WHILE RUNNING DRILLSTEM TESTING TOOLS IN THE HOLE.
A Hydraulic system in the tool allows the valve to open slowly with applied drillstring or tubing weight, after the packer has been set. The time delay mechanism prevents premature opening if bridges or tight sections are suddenly encountered while running drillstem testing tools into the well. In addition, the Full Bore Shut-In Tool is used to obtain flow periods and shut-in periods for drillstem testing. Any number of flow periods or shut-in periods may be obtained with each trip in the hole. An optional Indexing J-Slot Mechanism is available to allow the tool to remain in the locked open position, while running the tools into the well.