Method for breaking rock by directing high velocity jet into pre-drilled bore
US4103971A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 31, 1976 |
| Grant date | Aug 1, 1978 |
| Priority date | — |
| Expiry date | Aug 31, 1996 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB26F3/004
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A hard compact material such as rock is broken by directing a high velocity jet of relatively incompressible fluid, such as water, into a hole which is drilled in the material to be broken. The jet is generated by a nozzle in alignment with the hole and is suddenly arrested in the hole in appropriate position with respect to adjacent free surfaces of the material. A jet stagnation pressure is created in the hole of sufficient magnitude and duration or jet repetion rate to break the material towards the free surfaces. Preferably, a secondary nozzle emits fluid for filling partially or wholly the hole prior to generating the high velocity jet by a primary nozzle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.