Bit assembly utilizing carbide insert
US4883129A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 1988 |
| Grant date | Nov 28, 1989 |
| Priority date | — |
| Expiry date | Dec 16, 2008 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21C35/1933
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Ground engaging bits used in abrasive road grading applications utilizing carbide inserts brazed to the leading face of the steel tip are beneficial on motor grader blades. Commercial road grading bit assemblies used consistent thickness, rectangular carbide inserts brazed to the leading edge of the steel tip. Due to wear and high residual stresses imparted upon the insert from the brazing operation, premature cracking and breaking of the carbide inserts occur. The subject bit arrangement utilizes a carbide insert with a flat rectangular cutting face of non-constant thickness brazed to a leading edge of a steel body. The carbide insert has a thickness that increases from the top of the carbide insert and reaches a maximum at the bottom of the steel body, where bit wear is the greatest. The increasing thickness of the carbide tip extends bit life over the current rectangular design and allows for a more efficient and economical use of the carbide. This design also reduces the residual stresses in the carbide insert which normally occur during the brazing operation, thus substantially reducing cracking and breaking, and further extending bit life.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.