Nuclear Valves

Abstract

Abstract This chapter describes how the ASME Boiler and Pressure Vessel Code requirements are implemented for safety-related nuclear valves. It explains the relevancy of the ASME Code requirements for safety-related nuclear valves using the latest issue of the Code. The chapter discusses the role of system and component design engineers, as well as the integrity of the Manufacturer. It provides a historical perspective for the Code rules, cross-referencing other Subsections of the Code. The chapter states that the Owner’s responsibilities for system design play an important part in establishing the rules applicable to the Design Specification for each safety-related valve. It also covers the operational and qualification requirements for the procurement of these items from the Manufacturer. The chapter discusses these items for different service conditions with the aid of schematics and references. It then provides details of the ASME B16.34 historical development and provides the current reference dimensional standards from the 2013 and 2015 editions of the Code for use in the construction of “N” stamped valves based on the Code’s B16.34 reference. A list of widely used Valve Standards referenced in ASME B31 Piping Codes is also presented. The coverage on pressure-relief valves includes details on activity underway at Section III to clarify requirements related to pilot-operated and power-actuated pressure relief valves. It also includes details relevant to QME-1 relating to qualification testing required for active valves used in nuclear power plants. History Late Douglas B. Nickerson was the original author of this chapter. Marcus N. Bressler updated the second edition and third editions. Guy A. Jolly, updated this chapter specific to valves for 4th edition and 5th editions. The current online edition was updated by Jason Lambin and the ASME Working Group on Valves.