Surface control system adaptive downhole weight on bit/torque on bit estimation and utilization
US10648321B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 4, 2017 |
| Grant date | May 12, 2020 |
| Priority date | — |
| Expiry date | Feb 18, 2038 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B44/04
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A drilling rig apparatus is disclosed for improving autodriller control during directional drilling. A BHA determines a relationship between downhole WOB and downhole differential pressure and sends the relationship to a surface controller. The relationships may be sent on a set periodic basis or dynamically in response to the relationships over time differing from each other above a threshold amount. The surface controller estimates downhole WOB by inputting surface differential pressure into a formula implementing the relationship from downhole. The estimated downhole WOB is input into the autodriller for control and is used to estimate MSE. Downhole WOB, either estimated or actual values, may further be used to determine a ratio between downhole WOB and surface-determined WOB values. If the ratio falls below zero in comparison to a prior ratio, then a slack-off rate is adjusted until the ratio reaches zero or a positive value again.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.