Mine tool roof bit insert and a method of drilling therewith
US4527638A · kind A · utility
22Cited by
16References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 25, 1983 |
| Grant date | Jul 9, 1985 |
| Priority date | — |
| Expiry date | May 25, 2003 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/58
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A mine tool roof bit insert geometry of a 30.degree. top relief angle between the top cutting edge and the top trailing edge and a radius of curvature of 1/16 inch at the corners improves the maximum wear and penetration rate when drilling into sandstone and a method therewith is described.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.