Development of a Thermal-Sprayed Coating System to Mitigate Ice Accumulation and Freezing Damage in Carbon Steel Pipes

摘要

A multi-layered thermal-sprayed coating system, developed as a resistive heating system, was deposited on a carbon steel pipe. The feasibility of using a 50Cr-50Ni coating as a heating element on top of a conductive substrate was studied. Alumina was deposited to serve as an electrically insulating layer between the metal coating and the substrate to restrict the flow of electrons from the metal alloy heating element to the steel substrate. Continuity, homogeneity, and adhesion of the coating were qualitatively analyzed by studying scanning electron microscope images. The performance of the heating system was determined by measuring the ice temperature and the times required to heat and melt the solid ice that was formed within the pipe. It was found that the coating system was able to generate the heat required to melt the ice in the pipe, thus avoiding the detrimental effects on the pipe of internal liquid freezing. This suggests that the proposed novel resistive heating system can be used on an industrial scale to mitigate or avoid the detrimental effects of ice accumulation in steel and other metallic pipes.