The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 03, 1976
Filed:
Sep. 12, 1973
Anthony William Russell, Cheltenham, EN;
Other;
Abstract
For the directional drilling of boreholes, the orientation or roll angle of the drill head or mud-motor in the borehole has to be ascertained for steering purposes. The roll angle is determined, during drilling, by sensing at the location of the drilling tool in the borehole the values of the earth's magnetic field strength in two axes transverse to the main tool axis, signalling these values to the drilling station and translating them according to the direction and inclination of the borehole axis, which are known and normally updated at intervals between drilling runs. The down-hole assembly, located in a fixed attitude to the mud-motor, requires only static magnetic sensors. A resolver in a surface indicating unit provides for the indication of the roll angle as the angle determined by the sensors, translated according to the borehole information by the addition of an angle precalculated and selected from tables, calculated in a computation center, or calculated by computation in the indicating unit.