Drill bit inserts enhanced with polycrystalline diamond

摘要: A drill bit has means at one end for connecting the to a string and plurality of inserts other crushing rock be drilled. The have cemented tungsten carbide body partially embedded in least two layers protruding drilling portion insert. outermost layer contains polycrystalline diamond particles or carbonitride elements selected from group consisting W, Ti, Ta, Cr, Mo, Cb, V, Hf Zr. remaining adjacent are transition each comprising composite containing crystals, carbide, titanium carbonitride. average size is greater than particles; sizes particles. In particular, contain and/or with grain less micrometer. extends along length grip bit.