Detection of water saturation in insulation at cased road crossings

摘要

A method for detecting water saturation of thermal insulation located between a flowline and metal sheathing at a location where the flowline is positioned in a metal casing. Electrical resistance measurements are made between the metal sheathing and flowline, between the casing and the sheathing, and between the casing and the flowline. The resistance values and/or direct voltage and current measurements are used to determine actual resistance through the insulation as an indication of water saturation.