METHOD FOR IMPROVING INCLINATION COMPASS VIBRATION RESISTANCE Russian patent published in 2014 - IPC E21B47/02 

FIELD: measurement equipment.

SUBSTANCE: invention refers to measurement equipment and may be used in petroleum geophysics for control of three-dimensional position of well path during building. Method for improving vibration resistance of inclination compass consists in the following: digital signal processor sequentially with predetermined polling period takes readings from three magnetometric and six accelerometer sensors using analog-to-digital converter, thus forming nine arrays of accumulate measures: Gx[0…N-1], Gy[0…N-1], Gz[0…N-1], Vx[0…N-1], Vy[0…N-1], Vz[0…N-1], Hx[0…N-1], Hy[0…N-1], Hz[0…N-1], also current temperature is read by temperature sensor. Then digital signal processor calculates progressive average values Gxav, Gyav, Gzav, Vxav, Vyav, Vzav, maximum and minimum values Gxmax, Gxmin, Gymax, Gymin, Gzmax, Gzmin, and compares differences (GxMax-Gxav), (Gxav-Gxmin), (Gymax-Gyav), (Gyav-Gymin), (Gzmax-Gzav), (Gzav-Gzmin) with "flicker" threshold, characterized by upper of threshold of maximum or minimum value deviation from the average value. At that if any difference is lower than "jitter" threshold, inclination compass switches to statics mode, in this mode processor stores a data and two more measures with specified interval, calculates directional angles, stores them in memory with mark "CT1", "CT2", "CT3" for subsequent supply in well-logging tool when drilling ahead. If any difference is higher than "jitter" threshold, processor compares each measured value from accelerometers Gxi, Gyi, Gzi [i=0…N-1] with predetermined "overload" threshold value. At that if value of current i measure module is lower than "overload" threshold value, inclination compass switches to dynamics mode, and if current i measure module on any coordinate is higher or equal to threshold value, processor switches to "overload" mode. In "overload" mode all the i measures on all the three coordinates Gxi, Gyi, Gzi are replaced with i measures Vxi, Vyi, Vzi. At that when processor has determined current mode of measurement and filled arrays, accumulated measures are averaged on each coordinate of accelerometers. Besides processor averages values on each coordinate of magnetometers Hxav, Hyav, Hzav from arrays Hx[0…N-1], Hy[0…N-1], Hz[0…N-1], then inclination compass operates in normal mode.

EFFECT: providing measures vibration resistance under impact of vibrations on inclination compass during well-drilling.

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