The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 31, 1998
Filed:
Jan. 11, 1996
David Truax, Houston, TX (US);
Douglas Caraway, Kingwood, TX (US);
Stephen M Evans, Standish, GB;
Andrew Murdock, Stonehouse, GB;
Camco Drilling Group Limited of Hycalog, Stonehouse, GB;
Abstract
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.