METHOD FOR MEASURING THE THERMAL CONDUCTIVITY OF WELL CASING AND THE LIKE

摘要

A method for measuring the thermal conductivity of well casing in situ. The instrument consists of a probe several feet in length lowered into a well and decentralized so that it maintains contact with the casing wall. Two temperature sensors situated adjacent opposite ends of the probe are thermally insulated from an electrically heated intervening portion of the probe body. The probe is moved from one depth to another at a constant predetermined velocity, and the sensors continuously measure the temperature of the casing wall before and after passage of the heated probe portion thereover. The effective thermal conductivity of the casing is directly proportional to the flux applied by the heater and inversely proportional to the temperature change as the heater passes a point along the casing.