Selection of Materials for Heat Exchangers

1 his paper provides a U-J;P,G work for selecting heat exchangers materials especially those used in nuclear power plants. Typical examples of materials selection for heat exchanger tubing of nuclear power plants and condensers are presented. The paper brings out also, the importance of continued intensive R & D in materials in order to enhance the reliability and reduce cost by improving upon the existing materials by minor additions of alloying elements or new materials. The properties of Cr Mo alloys with minor additions of W, V, Nb and N are discussed in view of their use at elevated temperatures in the power industry. These alloys were found to provide considerable operation flexibility due to their low expansion coefficient and high thermal conductivity in comparison with the austenitic stainless steels. Also, the Ni base alloy Inconel 617. could be selected for his excellent combination of creep and hot corrosion resistance up to a temperature of a50 °C.