Method for determining leakage of outer pipe from inner pipe, involves calculating coefficient of correlation between temporal disposal of measured resistance value and time line of precipitation amount in area of ground above pipe

摘要

The method involves providing a district heating pipe that comprises an insulation material between an inner pipe and an outer pipe, and measuring electrical resistance of a sensor wire embedded in the insulating material against a conductor, the conductive inner pipe and the ground. A coefficient of correlation between a temporal disposal of the measured resistance value and a time line of amount of precipitation in an area of the ground above the heating pipe is calculated.