PROCEDE DE FABRICATION DE CORPS FRITTES COMPORTANT DES CONDUITS INTERIEURS, OUTIL A FILER POUR LA MISE EN OEUVRE DU PROCEDE ET OUTIL DE PERCAGE.

摘要

A drilling tool which has at least one helical fluid flow channel at its interior, is composed of a hard metal core having an exterior surface and a hard metal tubular casing having an interior surface. The casing encloses the core with their surfaces in firm contact so that the core and casing form a composite body. Each channel is formed as a groove in the surface of the core or casing.