Drilling efficiency through beneficial management of rock stress levels via controlled oscillations of subterranean cutting elements
US7341116B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 20, 2005 |
| Grant date | Mar 11, 2008 |
| Priority date | — |
| Expiry date | Nov 16, 2025 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B7/24
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A device and system for improving efficiency of subterranean cutting elements uses a controlled oscillation super imposed on steady drill bit rotation to maintain a selected rock fracture level. In one aspect, a selected oscillation is applied to the cutting element so that at least some of the stress energy stored in an earthen formation is maintained after fracture of the rock is initiated. Thus, this maintained stress energy can thereafter be used for further crack propagation. In one embodiment, an oscillation device positioned adjacent to the drill bit provides the oscillation. A control unit can be used to operate the oscillation device at a selected oscillation. In one arrangement, the control unit performs a frequency sweep to determine an oscillation that optimizes the cutting action of the drill bit and configures the oscillation device accordingly. One or more sensors connected to the control unit measure parameters used in this determination.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.