Chapter 13 was authored for the first edition by the late Douglas B. Nickerson, who held several memberships on Code Committees spread over several decades. He was associated with the design and qualification of pumps and valves, a topic that he covers in this chapter. Marcus Bressler agreed to undertake the updating of this chapter for the Second Edition. Douglas discusses those items that are the driving and controlling forces in hydraulic systems for nuclear power plants. The pump in each system drives the flow through the piping to provide the transfer of energy from one component to another. The valves control the flow through these fluid systems and thus the operation of the systems. Fluid systems have varying degrees of criticality, depending on their function. This commentary explains the relevancy of the ASME Code requirements for safety-related nuclear pumps and valves using the latest issue of the Code. The Code is limited to pressure-boundary requirements. Douglas states that because of this limitation of the scope of the Code, most conditions necessary to the satisfactory design of a nuclear pump or valve are not subjected to Code rules. The Design Specification specifies operational requirements and thus is the most important element in their function and approval. This commentary not only defines the applicable Code but also explains how these components function in their applications.
Chapter 13 also discusses the role of system design and component design engineers, as well as the integrity of the Manufacturer. Douglas provides a historical perspective for the Code rules, cross-referencing other Subsections of the Code. He notes that Owner's Responsibilities for system design plays an important part in establishing the rules applicable to the Design Specification for each safety-related pump and valve. Drawing upon considerable practical experience, Douglas covers operational and qualification requirements for the procurement of these items from the Manufacturer. He discusses these items for different service conditions with the aid of schematics and references. Marcus, a member of the subgroup on Design since 1974, and Chairman of the working group on Valves from 1974 to 1977, provides the background to the development of the design rules for valves, and updates the Chapter to the 2007 Edition of the Code.