Mud turbine tachometer
US4647853A · kind A · utility
37Cited by
9References
32Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 30, 1983 |
| Grant date | Mar 3, 1987 |
| Priority date | — |
| Expiry date | Sep 30, 2003 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In an MWD measurement system, the speed of rotation of a downhole turbine is measured by the interaction of a triaxial magnetometer in a sensor package and a permanent magnet attached to the turbine shaft. The triaxial magnetometer may be part of an existing MWD system for measuring borehole directional parameters. The magnet is a strong magnet mounted on the turbine shaft perpendicular to the axis of the turbine and the axis of the drill string.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.