Apparatus for drill stem testing

Claim 1

APPARATUS FOR HYDRAULICALLY INFLATING AN INFLATABLE PACKER AFFIXED TO THE EXTERIOR OF A DRILL STEM RESPONSIVE TO EXERTION OF FLUID PRESSURE IN THE BORE OF THE DRILL STEM, COMPRISING: A FIRST DRILL STEM SECTION HAVING AN OUTER TUBULAR MEMBER AND AN INNER TUBULAR MEMBER DEFINING A SPACE THEREBETWEEN; SAID INNER TUBULAR MEMBER INCLUDING AN ELASTIC TUBULAR SECTION DEFORMABLE BY FLUID PRESSURE WITHIN THE BORE OF THE DRILL STEM, AND A NONMAGNETIC TUBULAR SECTION; A SUBSTANTIALLY INCOMPRESSIBLE LIQUID IN SAID SPACE; A CONTROL VALVE IN SAID SPACE COMPRISING A VALVE STEM, A VALVE HOUSING FOR SAID VALVE STEM HAVING FIRST, SECOND, AND THIRD PORTS, SAID FIRST PORT BEING IN HYDRAULIC COMMUNICATION WITH SAID SPACE, SAID VALVE STEM INCLUDING MEANS TO HYDRAULICALLY INTERCONNECT SAID FIRST AND SECOND PORTS WHEN SAID STEM IS IN A FIRST POSITION THEREOF, AND TO HYDRAULICALLY INTERCONNECT SAID FIRST AND THIRD PORTS WHEN SAID STEM IS IN A SECOND POSITION THEREOF; MEANS IN SAID VALVE HOUSING URGING SAID VALVE STEM TOWARD SAID FIRST POSITION THEREOF; MEANS INCLUDING FIRST CHECK VALVE MEANS HYDRAULICALLY INTERCONNECTING SAID THIRD PORT TO SAID PACKER, ADAPTED TO ALLOW FLUID FLOW ONLY FROM SAID THIRD PORT TO SAID PACKER TO INFLATE SAID PACKER;