05259468 is referenced by 24 patents and cites 7 patents.

Rotational orientation of a drillstring is monitored a plurality of times during each rotation of a drillstring for monitoring the rotational orientation of a curve drilling assembly on a drillstring. A defined rotational orientation of a downhole location on the drillstring with respect to the curve drilling assembly is established. At least one reference signal generator having a known relationship to the down hole location on the drillstring and that rotates with the drillstring is provided at the surface. A reference signal is generated each time a reference signal generator rotates past a detector. A pressure signal is generated each time the drillstring rotates through the defined rotational orientation with respect to the drill bit steering device. Occurrences of the plurality of surface reference signals and the pressure signal are timed and compared for monitoring the rotational orientation of the drill bit steering device.

Title
Method of dynamically monitoring the orientation of a curved drilling assembly and apparatus
Application Number
592433
Publication Number
5259468
Application Date
October 3, 1991
Publication Date
November 9, 1993
Inventor
Warren J Winters
Tulsa
OK, US
Tommy M Warren
Coweta
OK, US
Agent
Frank J Sroka
Richard A Kretchmer
James A Gabala
Assignee
Amoco Corporation
IL, US
IPC
E21B 21/08
E21B 7/06
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