Nuclear Power Plant Safety and Mechanical Integrity

Design and Operability of Mechanical Systems, Equipment and Supporting Structures

George Antaki, Ramiz Gilada

• Publisher: Butterworth-Heinemann
• Year: 2014
• ISBN:
  9780124173064
• Topic: Business
• Subtopic: Industrial Management
• Index: Business

One of the most critical requirements for safe and reliable nuclear power plant operations is the availability of competent maintenance personnel. However, just as the nuclear power industry is experiencing a renaissance, it is also experiencing an exodus of seasoned maintenance professionals due to retirement. The perfect guide for engineers just entering the field or experienced maintenance supervisors who need to keep abreast of the latest industry best practices, Nuclear Power Plant Maintenance: Mechanical Systems, Equipment and Safety covers the most common issues faced in day-to-day operations and provides practical, technically proven solutions. The book also explains how to navigate the various maintenance codes, standards and regulations for the nuclear power industry.

• Discusses 50 common issues faced by engineers in the nuclear power plant field
• Provides advice for complying with international codes and standards (including ASME)
• Describes safety classification for systems and components
• Includes case studies to clearly explain the lessons learned over decades in the nuclear power industry

Chapter 1

Regulations, Codes, and Standards

Abstract

Chapter 1 covers the regulations that govern the design, construction, and operation of mechanical systems and components in nuclear power plants. Regulations are the building blocks of nuclear power plant engineering; they are defined in each plant's safety analysis report (SAR), and they must be understood and followed at each step of the engineering process. Following the regulations, we address Codes and Standards, with emphasis on the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (B&PV Code) because it covers piping systems, vessels, pumps, and valves, which are of particular interest in this book. We close this chapter explaining how structures, systems, and components (SSCs) are classified into safety classes, seismic categories, and essential classes.

Keywords

ACI code; Advisory committee on reactor safeguards (ACRS); AISC & AISI Codes; ANS; ASTM; AWS; IEEE standards; ANSI/ASME B31.1; ASME B&PV; ASME O&M; ASME Section III division 1; Boundaries; Classifications; Code cases; Code of federal regulations 10 CFR part 50; Codes and standards; Design; Essential; General design criteria; Generic letters; Bulletins and information notices; Inservice inspection; Loadings; NRC functions and organization; NUREGs; Regulations; Codes and standards; Regulatory guides; Safety class 1, 2 & 3; Seismic category; Service levels; Standard review plan; Structures, systems and components (SSCs); Testing

Chapter 1 covers the regulations that govern the design, construction, and operation of mechanical systems and components in nuclear power plants. Regulations are the building blocks of nuclear power plant engineering; they are defined in each plant's safety analysis report (SAR), and they must be understood and followed at each step of the engineering process. Following the regulations, we address Codes and Standards, with emphasis on the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (B&PV Code) because it covers piping systems, vessels, pumps, and valves, which are of particular interest in this book. We close this chapter explaining how structures, systems, and components (SSCs) are classified into safety classes, seismic categories, and essential classes.

1.1. Requirements

1.1.1. Regulation

Why start the book with regulations?

Engineering activities at a nuclear power plant are highly regulated. An engineer in a nuclear power plant has to focus on three types of requirements, all of them essential and complementary: (1) following the company procedures, (2) following good engineering practice (codes, standards, guides, etc.), and (3) Following the regulations applicable at the plant.

It is useful to first look at the regulatory aspect of nuclear plant engineering in the United States, before turning our attention to codes and standards, because nuclear power regulations control the application of codes and standards, and provide supplementary requirements that are not contained in codes and standards. Also, regulations control how to document engineering issues and their resolution.

How are engineering activities regulated in the nuclear power industry?

The engineering of nuclear power plants is closely regulated by the US Nuclear Regulatory Commission (NRC). The NRC was formed from the Atomic Energy Commission (AEC) through the Energy Reorganization Act of 1974, which replaced the Atomic Energy Act of 1954. It made the NRC a regulatory agency, no longer involved in the development and promotion of nuclear power as was its predecessor the AEC.

The NRC is empowered by the Congress to regulate and provide oversight of the complete life cycle of nuclear power plants, from design and construction, through operation, life extension, and decommissioning.

What are the functions of the NRC?

The NRC has several functions, which include: (1) to develop regulations and guidance, (2) to license applicants to operate the nuclear facility; (3) to oversee compliance with the licensing basis and safety requirements of the plant; (4) to evaluate operational experience and communicate lessons learned, and to impose plant-specific or industry-wide actions if necessary; (5) to conduct research; and (6) to hold hearings to address safety concerns related to nuclear plant operations.

How is the NRC organized?

At the top of the NRC structure are five NRC Commissioners, including the chairperson. Reporting to the Commissioners is the NRC staff and the Advisory Committee on Reactor Safeguards (ACRS). Within the NRC staff, under the Executive Director of Operations, there are several departments, including four geographical regions, the office of Nuclear Reactor Regulation, the office of New Reactors, and the office of Nuclear Regulatory Research.

What is the ACRS?

The ACRS is an advisory group of foremost experts, independent of the NRC staff, who report directly to the Commission, with four primary objectives: (1) to review safety studies, (2) to advise the Commission on safety standards, (3) to review generic safety topics, and (4) to advise on radiation protection.

How are the regulations organized?

At the top of the hierarchy of regulations is the Code of Federal Regulations (CFR), for nuclear power the CFRs of interest are title 10, referred to as 10 CFR, in particular:

• 10 CFR Part 20 “Standards for Protection Against Radiation”

• 10 CFR Part 21 “Reporting of Defects and Noncompliance”

• 10 CFR Part 50 “Domestic Licensing of Production and Utilization Facilities”

• 10 CFR Part 100 “Reactor Site Criteria”

To what extent do the CFRs affect engineering?

The CFRs are the foundations over which the plant's SAR, codes, standards, and procedures are developed. They permeate every aspect of engineering. A good example is 10 CFR section 50.72 “Immediate Notification Requirements for Operating Nuclear Power Reactors.” This CFR section has specific requirements regarding reporting of conditions and activities to the NRC Operations Center. Certain conditions must be reported in as little as 4 hours.

What are the upper-level safety requirements?

10 CFR Part 50 contains Appendix A, which spells out upper-level general design criteria (GDC). The following GDCs are of particular interest in the design and qualification of SSCs:

• Criterion 1 “Quality Standards and Records”

• Criterion 2 “Design Bases for Protection Against Natural Phenomena”

• Criterion 3 “Fire Protection”

• Criterion 4 “Environmental and Missile Design Bases”

• Criterion 5 “Sharing of Structures, Systems, and Components”

• Criterion 13 “Instrumentation and Controls”

• Criterion 14 “Reactor Coolant Pressure Boundary”

• Criterion 15 “Reactor Coolant System Design”

• Criterion 16 “Containment Design”

• Criterion 17 “Electric Power Systems”

• Criterion 18 “Inspection and Testing of Electric Power Systems”

• Criterion 19 “Control Room”

• Criterion 21 “Protection System Reliability and Testability”

• Criterion 22 “Protection System Independence”

• Criterion 23 “Protection System Failure Modes”

• Criterion 24 “Separat...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Biography
• Preface
• Acknowledgments
• Acronyms and Description
• Chapter 1. Regulations, Codes, and Standards
• Chapter 2. Design Basis Loads and Qualification
• Chapter 3. Examination and Leak Testing
• Chapter 4. Suspended Systems
• Chapter 5. Supporting Structures
• Chapter 6. Materials and Aging Mechanisms
• Chapter 7. Operability and Industry Operating Experience
• Annex 1. Generic Letters
• Annex 2. Bulletins
• Index