Hardfacing around ball loading hole for earth-boring bit
US7891443B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 2008 |
| Grant date | Feb 22, 2011 |
| Priority date | — |
| Expiry date | Jan 8, 2029 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/46
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A rotary cone earth boring bit has at least one bit leg with a cone retaining ball passage that intersects an outer surface of the bit leg and is closed by a ball plug. An upwardly curved lower hardfacing bead is on the outer surface of the bit leg at least partially below the ball plug. A downwardly curved upper hardfacing bead is on the outer surface of the bit leg at least partially above the ball plug. The upper hardfacing bead has leading and trailing ends that join the lower hardfacing bead. The upper and lower hardfacing beads define a generally elliptical perimeter surround the ball plug. At least one transverse bead is above the upper hardfacing bead and leads generally upwardly and circumferentially from a leading edge of the bit leg to a trailing edge of the bit leg.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.