Determination of the orientation of a dowhole device

• Main Authors: MCCLURE PAUL ANTHONY DONEGAN, PRICE GREGORY, ROSS DAVID
• Format: Patent
• Language: Norwegian
• Published: 09.12.2005
• Subjects: EARTH DRILLING; EARTH DRILLING, e.g. DEEP DRILLING; FIXED CONSTRUCTIONS; GYROSCOPIC INSTRUMENTS; MEASURING; MEASURING DISTANCES, LEVELS OR BEARINGS; MINING; NAVIGATION; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY; PHYSICS; SURVEYING; TESTING

For måling av en forskjøvet stabilisatoranordnings orientering i en omgivelse nede i et hull. En aksel roterer i forhold til stabilisatoranordningen, og signalutløsere er anordnet på kjente steder på både den roterende aksel og stabilisatoranordningen. Når signalutiøseme på hver komponent er brakt i flukt med hverandre utløses et signal og en tykkpuls genereres. Tuningen av de genererte signaler benyttes sammen med den målte orientering av akselen, oppnådd ved anvendelse av en vinkelmålesensor, så som et akselerometer og/eller et magnetometer, for å beregne den forskjøvne stabilisatoranordnings orientering. A method for measuring the orientation of an offset stabiliser device in a downhole environment, and a suitably modified device to enable this measurement, are disclosed. A shaft rotates relative to the stabiliser device, and signal trigger means are provided at known locations on each of the rotating shaft and the stabiliser device. When the signal trigger means on each component are brought into alignment, a signal is triggered. The signal trigger means could be a pair of apertures, which results in the generation of a pressure pulse, or a mechanical clapper assembly, which results in an acoustic signature. The timing of the generated signals are used together with the measured orientation of the shaft, obtained using an angular measurement sensor such as an accelerometer and/or magnetometer, in order to calculate the orientation of the offset stabiliser device.