Stressed relieved bit leg for an earth boring bit
US4431066A · kind A · utility
4Cited by
2References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 18, 1981 |
| Grant date | Feb 14, 1984 |
| Priority date | — |
| Expiry date | Feb 18, 2001 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/08
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An earth boring bit has features to reduce stress concentration. The earth boring bit is of the type having three bit legs, each bit leg having a depending bearing pin for rotatably carrying a cutter. An annular fillet is formed at the junction of the bearing pin and the bit leg for receiving a seal ring. To relieve stress above the fillet and on the inside surface of the bit leg, a depression is formed. The depression is formed in the inside surface of the bit leg with a lower edge commencing at the top of the fillet. The depression is curved in vertical cross-section and is located behind the backface of the cutter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.