Abstract: A conduit centralizer comprises segmented, sliding means connected by a plurality of axially extending, outwardly bowed leaf springs. Each sliding means is formed by the hinged connection of a plurality of double walled segments. The ends of the leaf springs are respectively inserted within the double walled segments and welded to both the inner and outer walls of the segments, thus providing an extremely rigid structure which is fabricated without machining operations.

Abstract: The disclosure relates to an improved apparatus for effecting the cementing of a liner at the bottom of a well bore. The liner sleeve assembly is inserted into the well bore on a hanger which is detachably connected to a running tool, which, in turn is connected to the work string by a torque transmitting expansion joint. The running tool may be fluid pressure actuated to set the hanger. In the event of failure of the fluid pressure setting operation, the hanger may be mechanically set by rotation of the work string transmitted to the running tool by the torque transmitting expansion joint.