ASME Applicability for Small Modular Reactors

Small Modular Reactor (SMR) designs for the pressurized light-water nuclear steam supply system (NSSS) have instituted various and unique features in the pressure vessels and piping industry. Selection of materials and component geometries are creating an enviable opportunity for the respective design engineers to integrate and expand the use of the full complement of Subsections within Section III of the ASME Boiler and Pressure Vessel Code. This paper discusses the prescribed requirements contained within these tried and proven Code rules as may be applicable to the pressure vessels and piping components and assemblies that will make up the next generation of SMRs. A cross correlation between the current licensing regulations that specifically address the pertinent Codes and standards for the “traditional” pressurized light water reactors is outlined in terms of “equivalent” components within the SMR designs currently on the drawing boards. Specifically, at least one pathway to compliance with the current Codes and standards promulgated within 10 CFR 50.55(a) is developed and discussed herein. The authors also concede that the suggested pathway to compliance is only one of what will prove to be a multiple set of solutions to the crossing the U.S. domestic licensing tightrope.