Patent ID: 9739136
Date: 2017-08-22
CPC Classifications: E21B,G01C

Claim:
1. An arrangement for calibrating sensors in a drilling equipment comprising: a movable carrier; a frame; a boom assembly mounted to turn about a turning axis vertical to the frame; an angle sensor for measuring a turning angle of the boom assembly in relation to the frame; gravity-based inclination sensors mounted to the boom assembly and rotating with the boom assembly about the turning axis for measuring inclination in the direction of two co-ordinate axes that are perpendicular to each other; inclination sensors mounted to the frame, which remain stationary with the frame during turning of the boom assembly; and a control unit arranged, when turning the boom assembly about the turning axis to a plural number of different turning angle positions in relation to the frame, to measure the value of the turning angle and the inclination values provided by the gravity-based inclination sensors for each turning angle position and calculate, on the basis of the measured turning angle value and the inclination values provided by the gravity-based inclination sensors, deviations of the values provided by the inclination sensors from the actual inclination angle, and to measure, during calibration, inclination values of inclination sensors mounted to the frame and remaining stationary with the frame during the turning of the boom assembly to measure the inclination of the frame, and to calculate by means of the gravity-based inclination sensors of the boom assembly, deviations of the inclination sensors mounted to the frame to measure the inclination of the frame.