Chapter 20
PWR Reactor Vessel Integrity and Internals Aging Management


The integrity of the reactor pressure vessel is critical to plant safety. A failure of the vessel is beyond the design basis. Therefore, the design requirements for vessels have significant margins to prevent brittle or ductile failure under all anticipated operating conditions. The early vessels in the United States were designed to meet the requirements of ASME BPVC Section VIII. The design requirements for these vessels were supplemented by special requirements based on earlier U.S. Navy design experiences. In general, the allowable stress limits were lower than vessels designed to later ASME BPVC Section III requirements. The early design codes did not include the rigorous fracture toughness requirements found in today's codes. Section VIII relied on a “fracture-safe” design approach, which sought to ensure that pressure vessels were operated in a temperature regime (upper-shelf region) where small flaws or cracks would not affect the load-carrying capacity of the structure.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In