2023 ASME Boiler and Pressure Vessel Code, Section III: Rules for Construction of Nuclear Power Plant Components, Division 1, Subsection NB: Class 1 Components

Published by ASME International, 07/01/2023


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ASME BPVC-III NB, 2023 Edition – Rules for Construction of Nuclear Power Plant Components, Division 1: Class 1 Components

ASME Section III, Division 1, Subsection NB – This Subsection contains requirements for the material, design, fabrication, examination, testing and overpressure protection of items which are intended to conform to the requirements for Class 1 construction. The rules of Subsection NB cover the requirements for assuring the structural integrity of items.

What are the key changes for 2023 BPVC Section III, Division 1, Subsection NB (ASME BPVC-III NB)?

  • NB-2121(a) has been revised to permit the use of advanced manufacturing. This revision is to permit use of advanced manufacturing product forms not included in Section II, Part D, Subpart 1, Tables 2A, 2B, or Article NB-2000, provided that the product form meets the requirements of Mandatory Appendix XXVIII.
  • NB-2321.2 has been revised to remove the requirement to use full-size test specimens, and test-specimen requirements were adjusted to be in accordance with SA-370.
  • NB-5000 has been updated to permit the use of newly published Section XI, Division 2, Requirements for Reliability and Integrity Management (RIM) Programs for Nuclear Reactor Facilities, as a basis for designing for inservice monitoring and nondestructive examination (NDE).
  • NB-5540 has been developed to permit the use of CP-189 as an acceptable NDE personnel qualification standard. Section III previously required qualification of examiners only to SNT-TC-1A, while Section XI requires personnel qualification per CP-189.

General Product Information:

Document Type PDF
ISBN 978-0-7918-7569-8
Pages 238
Document Language English
Publisher American Society of Mechanical Engineers (ASME)
Status Current