High-strength/high-toughness alloy steel drill bit blank
US7044243B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 31, 2003 |
| Grant date | May 16, 2006 |
| Priority date | — |
| Expiry date | Jan 26, 2024 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/55
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Drill bit reinforcing members or blanks of this invention are formed from high-strength steels having a carbon content less than about 0.3 percent by weight, a yield strength of at least 55,000 psi, a tensile strength of at least 80,000 psi, a toughness of at least 40 CVN-L, Ft-lb, and a rate of expansion percentage change less than about 0.0025%/° F. during austenitic to ferritic phase transformation. In one embodiment, such steel comprises in the range of from about 0.1 to 0.3 percent by weight carbon, 0.5 to 1.5 percent by weight manganese, up to about 0.8 percent by weight chromium, 0.05 to 4 percent by weight nickel, and 0.02 to 0.8 percent by weight molybdenum. In another example, such steel comprises in the range of from about 0.1 to 0.3 percent by weight carbon, 0.9 to 1.5 percent by weight manganese, 0.1 to 0.5 percent by weight silicon, and one or more microalloying element selected from the group consisting of vanadium, niobium, titanium, zirconium, aluminum and mixtures thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.