Method and apparatus for percussion drilling
US11448013B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 5, 2018 |
| Grant date | Sep 20, 2022 |
| Priority date | — |
| Expiry date | Apr 21, 2041 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B44/00
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method for maintaining a penetration rate of a drilling operation, where the drilling operation is carried out by a drilling rig having a hammer drill apparatus. A reference penetration rate for the hammer drill bit is chosen. A starting depth of cut is computed from the reference penetration rate, the measured hammer frequency, and the drill bit parameters. The system measures the actual penetration rate of the drill bit and computes an actual depth of cut. From the actual depth of cut a target bit rotation speed is computed. The target rotation speed is compared to the actual rotation speed, and the rotation speed is adjusted up or down to set the bit rotation speed at a value that will maintain the target rotation speed, notwithstanding changes in hammer frequency or ground conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.