Drill bit inserts enhanced with polycrystalline diamond
US5370195A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 20, 1993 |
| Grant date | Dec 6, 1994 |
| Priority date | — |
| Expiry date | Sep 20, 2013 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/567
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A drill bit has means at one end for connecting the bit to a drill string and a plurality of inserts at the other end for crushing the rock to be drilled. The inserts have a cemented tungsten carbide body partially embedded in the drill bit and at least two layers at the protruding drilling portion of the insert. The outermost layer contains polycrystalline diamond and particles of carbide or carbonitride of elements selected from the group consisting of W, Ti, Ta, Cr, Mo, Cb, V, Hf and Zr. The remaining layers adjacent the polycrystalline diamond layer are transition layers each comprising a composite containing diamond crystals, particles of tungsten carbide, and particles of titanium carbonitride. The average size of the diamond particles in the polycrystalline diamond layer is greater than the average size of the carbide or carbonitride particles; and the average size of the diamond particles in the transition layers is greater than the average sizes of the carbide and carbonitride particles. In particular, the transition layers contain particles of carbide and/or carbonitride with average grain sizes of less than one micrometer. The outermost layer of polycrystalline diamond e…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.