[Federal Register Volume 83, Number 108 (Tuesday, June 5, 2018)]
[Notices]
[Pages 26111-26112]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-11996]
-----------------------------------------------------------------------
NUCLEAR REGULATORY COMMISSION
[NRC-2014-0023]
Effect of LWR Water Environments on the Fatigue Life of Reactor
Materials
AGENCY: Nuclear Regulatory Commission.
ACTION: NUREG; issuance.
-----------------------------------------------------------------------
SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing NUREG/
CR-6909, Revision 1, ``Effect of LWR Water Environments on the Fatigue
Life of Reactor Materials.'' This report summarizes the results of NRC
research efforts and work performed at Argonne National Laboratory on
the fatigue of piping and pressure vessel steels in light-water reactor
(LWR) environments. Revision 1 of this report provides updates and
improvements to the environmental fatigue correction factor approach
based on an extensive update to available laboratory fatigue data from
testing and results available since this report was first published in
2007. This final document also incorporates changes to address public
comments provided on the draft of Revision 1 of NUREG/CR-6909.
ADDRESSES: Please refer to Docket ID NRC-2014-0023 when contacting the
NRC about the availability of information regarding this document. You
may obtain publicly-available information related to this document
using any of the following methods:
Federal Rulemaking Website: Go to http://www.regulations.gov and search for Docket ID NRC-2014-0023. Address
questions about NRC dockets to Jennifer Borges; telephone: 301-287-
9127; email: [email protected]. For technical questions, contact
the individuals listed in the FOR FURTHER INFORMATION CONTACT section
of this document.
NRC's Agencywide Documents Access and Management System
(ADAMS): You may obtain publicly-available documents online in the
ADAMS Public Documents collection at http://www.nrc.gov/reading-rm/adams.html. To begin the search, select ``ADAMS Public Documents'' and
then select ``Begin Web-based ADAMS Search.'' For problems with ADAMS,
please contact the NRC's Public Document Room (PDR) reference staff at
1-800-397-4209, 301-415-4737, or by email to [email protected]. The
ADAMS accession number for each document referenced (if it is available
in ADAMS) is provided the first time that it is mentioned in this
document. Revision 1 of NUREG/CR-6909 is available in ADAMS under
Accession No. ML16319A004.
NRC's PDR: You may examine and purchase copies of public
documents at the NRC's PDR, Room O1-F21, One White Flint North, 11555
Rockville Pike, Rockville, Maryland 20852.
FOR FURTHER INFORMATION CONTACT: Robert Tregoning, Office of Nuclear
Regulatory Research, telephone: 301-415-2324, email:
[email protected]; or Appajosula Rao, Office of Nuclear
Regulatory Research, telephone: 301-415-2381, email:
[email protected], U.S. Nuclear Regulatory Commission, Washington
DC 20555-0001.
SUPPLEMENTARY INFORMATION:
The American Society of Mechanical Engineers Boiler and Pressure
Vessel Code (Code) provides rules for the design of Class 1 components
of nuclear power plants. Appendix I to Section III of the Code contains
fatigue design curves for applicable structural materials. However, the
effects of LWR water environments are not explicitly addressed by the
Code design curves. The existing fatigue strain-vs.-life ([epsi]-N)
data illustrate potentially significant effects of LWR water
environments on the fatigue resistance of pressure vessel and piping
steels. Under certain environmental and loading conditions, fatigue
lives in water relative to those in air can be significantly lower for
austenitic stainless steels, nickel alloy materials, carbon steels, and
low-alloy steels. In March 2007, Revision 0 of NUREG/CR-6909 (ADAMS
Accession No. ML070660620) was issued. That report was the technical
basis document for NRC Regulatory Guide (RG) 1.207, Revision 0,
``Guidelines for Evaluating Fatigue Analyses Incorporating the Life
Reduction of Metal Components Due to the Effects of the Light-Water
Reactor Environment for New Reactors'' (ADAMS Accession No.
ML070380586). Revision 0 of NUREG/CR-6909 summarized the work performed
at Argonne National Laboratory on the fatigue of piping and pressure
vessel steels in LWR coolant environments. That report evaluated the
existing laboratory fatigue data to identify the various materials,
environmental, and loading parameters that influence fatigue crack
initiation and summarized the effects of key parameters on the fatigue
lives of pressure vessel and piping steels. The report presented models
for estimating fatigue lives as a function of material, loading, and
environmental conditions, and described the environmental fatigue
correction factor for incorporating the effects of LWR coolant
environments into Code fatigue evaluations.
Revision 1 of NUREG/CR-6909 provides updates and improvements to
the environmental fatigue correction factor approach based on
additional laboratory fatigue data and other results available since
2007. On April 17, 2014 (79 FR 21811), a draft of Revision 1 was
noticed in the Federal Register for public comment under Docket ID NRC-
2014-0023. The public comment period ended on June 2, 2014. The final
version of Revision 1 of NUREG/CR-6909 reflects changes made to address
the public comments. Appendix F of the document provides responses to
the public comments received.
Revision 1 of NUREG/CR-6909 is the technical basis document for
Revision 1 of RG 1.207, ``Guidelines for Evaluating the Effects of
Light-Water Reactor Water Environments in Fatigue Analyses of Metal
Components'' (ADAMS Accession No. ML16315A130). This RG describes
methods and procedures that the NRC staff considers acceptable for use
in determining the acceptable fatigue lives
[[Page 26112]]
of components evaluated by a cumulative usage factor calculation in
accordance with the fatigue design provisions in Section III, ``Rules
for Construction of Nuclear Power Plant Components,'' of the American
Society of Mechanical Engineers Boiler and Pressure Vessel Code to
account for the effects of LWR water environments. The NRC is issuing
Revision 1 of RG 1.207 concurrently with Revision 1 of NUREG/CR-6909
under a separate notice associated with Docket ID NRC-2014-0244.
The NRC notes that Revision 1 of RG 1.207 was issued in draft form
as a draft RG (DG-1309). The NRC published a notice of the availability
of DG-1309 in the Federal Register on November 24, 2014 (79 FR 69884),
under Docket ID NRC-2014-0244, with a public comment period that closed
on January 24, 2015. Public comments on DG-1309 and the NRC staff's
responses are available in ADAMS under Accession No. ML16315A127.
Dated at Rockville, Maryland, this 30th day of May 2018.
For the Nuclear Regulatory Commission.
Thomas Boyce,
Chief, Regulatory Guidance and Generic Issues Branch, Division of
Engineering, Office of Nuclear Regulatory Research.
[FR Doc. 2018-11996 Filed 6-4-18; 8:45 am]
BILLING CODE 7590-01-P