METHOD AND DEVICE FOR CONTROL OF NON-UNIFORMITY OF THICKNESS OF WALLS OF INACCESSIBLE PIPELINES Russian patent published in 2016 - IPC G01N27/83 G01B7/06 

FIELD: pipes.

SUBSTANCE: invention relates to monitoring the state of pipeline walls without their opening. Essence: alternating current is passed through the pipeline in longitudinal direction. Alternating current generated by magnetic field is measured at constant distance from the inner pipe wall in its inner cavity moving along with stops for the time of full turn around the pipe axis simultaneously at several points arranged on lengthwise pipe sections in turning about its axis. According to measurement of the average arithmetic value of magnetic field induction in each point of interruption of longitudinal movement. Wall thickness variation in points of the cylindrical surface of the pipe is installed as a function of direct proportionality from the ratio of the average value of magnetic field induction inside pipeline each point of interruption of longitudinal movement to its value in the measurement points with coefficient of proportionality equal to the predetermined value of thickness of intact pipe section.

EFFECT: technical result is upgraded accuracy, possibility of control from inside the pipe without making disturbances in process of measuring corrosion and sludge deposits and other defects.

2 cl, 2 dwg