04647853 is referenced by 38 patents and cites 11 patents.

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.

Title
Mud turbine tachometer
Application Number
6/537821
Publication Number
4647853
Application Date
September 30, 1983
Publication Date
March 3, 1987
Inventor
Martin E Cobern
Cheshire
CT, US
Agent
Fishman & Dionne
Assignee
Teleco Oilfield Services
CT, US
IPC
G01P 3/52
E21B 47/02
E21B 25/16
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