Method for applying hardfacing material to a steel bodied bit and bit formed by such method
US6568491B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 4, 2001 |
| Grant date | May 27, 2003 |
| Priority date | — |
| Expiry date | Jun 4, 2021 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/55
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A graphite or silicate plug is coated with a refractory metal and positioned in the cutter pocket of a steel bodied bit as molten hardfacing material is applied to the bit surface under high temperature conditions. The refractory metal cooperates with the hardfacing material to act as a wetting agent that draws the hardfacing material into intimate contact with the body of the displacement plug. The plug is removed leaving a composite pocket opening formed by the steel body and the hardfacing material. A PDC cutter inserted into the composite pocket opening closely adheres to the sides of the opening to reduce the gap between the cutter and the hardfacing material to hereby minimize the effects of erosion in the area of the gap. The wetting material on the displacement plug permits the hardfacing material to flow into and remain in position immediately adjacent the displacement body and in the small surface area between adjacent cutter pockets. The hardfacing material also cooperates with the-steel pocket to increase the surface area of the pocket recess that provides additional structural support to the cutter to improve the stability and retention of the cutter in the bit. The re…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.