Abstract: A conduit centralizer comprises segmented, sliding upper and lower collars connected by a plurality of axially extending, outwardly bowed leaf springs. Each collar is formed by the hinged connection on a plurality of segments in close fitting contact with the outer diameter of a pipe. The ends of the leaf springs are respectively inserted within the individual segments and welded to the segments. Individual collar segment sections or subassemblies comprising upper and lower collar segments secured to a single intermediate bowed leaf spring can then be interconnected to form a concentric centralizer.

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 invention provides a stop device for installation on a well conduit. The stop device is fabricated from semi-annular elements having one ends thereof pivotally interconnected by a hook and notch connection and the other ends stamped to provide apertured lugs traversed by a clamping device. The effective diameter of the stop is increased by a plurality of peripherally spaced, outwardly projecting notches formed in the top and bottom edges of the semi-annular elements.