Extremely Low Probability of Rupture Version 2 Probabilistic Fracture Mechanics Code (NUREG-2247)

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Publication Information

Manuscript Completed: July 2021
Date Published: August 2021

Prepared by:
Matthew Homiack, Giovanni Facco, Michael Benson,
Marjorie Erickson, and Craig Harrington

Matthew Homiack, NRC Project Manager

Office of Nuclear Regulatory Research
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

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xLPR Version 2 is a probabilistic fracture mechanics code for piping applications. The code was developed jointly by the U.S. Nuclear Regulatory Commission’s (NRC’s) Office of Nuclear Regulatory Research and the Electric Power Research Institute (EPRI). They engaged in a multiyear code development effort that built on the results of a successful pilot study. The code, which was designed, programmed, and tested under a rigorous software quality assurance program, provides regulators, industry, researchers, and the public with new quantitative capabilities to analyze the risks associated with nuclear power plant piping systems subject to active degradation mechanisms. Core capabilities of the code include modeling fatigue, stress-corrosion cracking, inservice inspection, chemical and mechanical mitigation, leak rates, and seismic effects. This report outlines how the NRC’s Office of Nuclear Regulatory Research and EPRI approached code development. It describes the basic design and operation of the software and the underlying models and theory. Results from verification and validation testing and independent reviews are provided. The report also covers sample code inputs and analysis results and provides recommendations for future development.

Page Last Reviewed/Updated Thursday, September 09, 2021