DRILL BIT MANUFACTURING METHOD

摘要

A method of manufacturing a drill bit or other drilling-related structure used for drilling into subterranean formations is herein disclosed where a blank is formed by placing a ferrous metal powder such as steel into a mold, sintering the ferrous metal powder to form a preformed blank, packing an abrasion- and erosion-resistant material such as tungsten carbide powder around the preformed blank, and infiltrating the preformed blank and tungsten carbide with a common binder such as a copperbased binder. For some materials, during sintering, the preformed blank may shrink in size relative to the mold enough to provide space between the mold and the preformed blank for a layer of abrasion- and erosion-resistant material. With other materials, a separate blank mold may be used to form the sintered blank which can then be inserted into the mold for infiltration. Accordingly, the same or substantially similarly configured mold can be used to form the preformed blank and the finished drill bit or drilling-related structure having a sintered steel core and a tungsten carbide shell infiltrated with a copper-based binder.