Determination of Thermal Characteristics of a New Buried Insulation

As a new type of composite pipe used for the direct-buried natural gas pipeline, the large-diameter steel pipe compounded coal-tar and enamel should be measured to obtain its thermal conductivity, but the measurement for the large-diameter composite pipes is usually not easy to be realized, and a complex test system and steps are needed. Based on Fourier's law, this paper introduces a simple method to test the thermal conductivity of a steel pipe compounded coal-tar and enamel with diameter of 660 mm. The data of the comprehensive thermal conductivity of 0.812 W / (m•K) is valuable. This method with the theoretical error of 2.1% can be referenced to test the thermal properties of the composite pipelines with large diameter.