Method for detecting drilling events from measurement while drilling sensors
US4876886A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 4, 1988 |
| Grant date | Oct 31, 1989 |
| Priority date | — |
| Expiry date | Apr 4, 2008 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B44/00
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Downhole Torque and Rate of Penetration are utilized to develop indications of formations having high porosity or of the development of an undergauge bit. Downhole torque is normalized by dividing it by the product of downhole weight on bit and bit size to produce Dimensionless Torque while Rate of Penetration is normalized by dividing it by the product of downhole weight on bit and rotary speed. The values of Dimensionless Torque and Normalized Rate of Penetration are compared to "normally" expected values of these quantities. Deviations from the normal values are taken as an indication of the occurrence of bit penetration of a highly porous formation or of the development of an undergauge or damaged bit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.