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AssigneeCamco Drilling Group Limited of Hycalog
InventorsDavid Truax, Douglas Caraway, Stephen M. Evans, Andrew Murdock
Estimating the term…
A drill bit comprises a main body part having a shank for connection to a drill string, an end face, an internal passage for supplying drilling fluid to the end face, a number of blades extending from the end face outwardly and longitudinally of the central axis of rotation of the bit, and a number of cutters mounted on each said blade. Each blade comprises a central metal core at least partly surrounded by solid infiltrated matrix material. A method of manufacturing such a drill bit includes the steps of providing a metal mandrel having said shank and internal passage, and providing on the mandrel, so as to be supported by it, a number of blade cores each having a portion extending outwardly and longitudinally of the central axis of the mandrel, casting infiltrated matrix material around at least a part of each core and around at least a part of the mandrel to form the blades, and then removing portions of the cores so as to detach each core from support by the mandrel to leave within each blade a core which is substantially wholly supported by the surrounding matrix material.
A drill bit comprising a main body part having a shank for connection to a drill string, an end face, an internal passage for supplying drilling fluid to said end face, a plurality of blades extending from said end face outwardly and longitudinally of the central axis of rotation of the bit, and a plurality of cutters mounted on each said blade, the main body part comprising a metal mandrel at least partly surrounded by solid infiltrated matrix material and each blade comprising a central metal core at least partly surrounded by matrix material, said matrix material having an average thickness of not more than about 10 mm, and each metal core being provided with a plurality of spaced recesses, registering with recesses in the matrix layer, to receive said cutters.
Dependencies are inferred from the claim text.