[Federal Register Volume 83, Number 178 (Thursday, September 13, 2018)]
[Notices]
[Pages 46524-46525]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-19941]


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NUCLEAR REGULATORY COMMISSION

[Docket No. NRC-2018-0168]


Weld Residual Stress Finite Element Analysis Validation

AGENCY: Nuclear Regulatory Commission.

ACTION: Draft NUREG; request for comment.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is requesting 
public comment on a draft NUREG entitled, ``Weld Residual Stress Finite 
Element Analysis Validation: Part II--Acceptance and Guidelines.'' This 
report proposes a methodology by which analysts can increase confidence 
in modeling capabilities for regulatory applications involving weld 
residual stress calculation. Specifically, the NRC staff posed four 
questions for consideration by the public (see SUPPLEMENTARY 
INFORMATION).

DATES: Submit comments by November 13, 2018. Comments received after 
this date will be considered if it is practical to do so, but the 
Commission is able to ensure consideration only for comments received 
before this date.

ADDRESSES: You may submit comments by any of the following methods:
     Federal Rulemaking Website: Go to http://www.regulations.gov and search for Docket ID NRC-2018-0168. Address 
questions about NRC dockets in Regulations.gov to Jennifer Borges; 
telephone: 301-287-9127; email: [email protected]. For technical 
questions, contact the individual listed in the FOR FURTHER INFORMATION 
CONTACT section of this document.
     Mail comments to: May Ma, Office of Administration, Mail 
Stop: TWFN-7-A60M, U.S. Nuclear Regulatory Commission, Washington, DC 
20555-0001.
    For additional direction on obtaining information and submitting 
comments, see ``Obtaining Information and Submitting Comments'' in the 
SUPPLEMENTARY INFORMATION section of this document.

FOR FURTHER INFORMATION CONTACT: Michael Benson, Office of Nuclear 
Regulatory Research, telephone: 301-415-2425, email: 
[email protected]; or Patrick Raynaud, Office of Nuclear 
Regulatory Research, telephone: 301-415-1987, email: 
[email protected]. Both are staff of the U.S. Nuclear Regulatory 
Commission, Washington, DC 20555-0001.

SUPPLEMENTARY INFORMATION: 

I. Obtaining Information and Submitting Comments

A. Obtaining Information

    Please refer to Docket ID NRC-2018-0168 when contacting the NRC 
about the availability of information for this action. You may obtain 
publicly-available information related to this action by any of the 
following methods:
     Federal Rulemaking Website: Go to http://www.regulations.gov and search for Docket ID NRC-2018-0168.
     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 ``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 draft NUREG on ``Weld Residual 
Stress Validation'' is available in ADAMS under Accession No. 
ML18242A007.
     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.

B. Submitting Comments

    Please include Docket ID NRC-2018-0168 in your comment submission.
    The NRC cautions you not to include identifying or contact 
information that you do not want to be publicly disclosed in your 
comment submission. The NRC will post all comment submissions at http://www.regulations.gov as well as enter the comment submissions into 
ADAMS. The NRC does not routinely edit comment submissions to remove 
identifying or contact information.
    If you are requesting or aggregating comments from other persons 
for submission to the NRC, then you should inform those persons not to 
include identifying or contact information that they do not want to be 
publicly disclosed in their comment submission. Your request should 
state that the NRC does not routinely edit comment submissions to 
remove such information before making the comment submissions available 
to the public or entering the comment into ADAMS.

II. Background

    Between 2008-2015, the Electric Power Research Institute and the 
NRC

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conducted a joint research program on weld residual stress (WRS) 
modeling under a memorandum of understanding. This research program 
consisted of several modeling and measurement studies on prototypic 
mockups to represent the residual stress state in safety-related 
nuclear components susceptible to primary water stress corrosion 
cracking, see NUREG-2162 (ADAMS Accession No. ML14087A118). Since then, 
the NRC has made use of the data gained in that research program to 
formulate a potential validation scheme for finite element modeling of 
WRS. The NRC's proposal is documented in a draft NUREG entitled, ``Weld 
Residual Stress Finite Element Analysis Validation: Part II-Proposed 
Validation Procedure'' (ADAMS Accession No. ML18242A007). The NRC is 
requesting public comment on this document. Specifically, the NRC would 
like feedback on four specific technical issues related to the proposed 
validation procedure:
    1. The NRC recommended the use of the average hardening approach in 
the current version of the draft NUREG (``average hardening'' meaning 
the arithmetic mean of isotropic and nonlinear kinematic results). 
Given the discussion in Section 5.2, please comment on the advantages 
and disadvantages of using either the averaging approach or isotropic 
hardening. What initial and recurring costs are foreseen in 
implementing either approach in future analyses?
    2. The NRC introduced four options for benchmark in Section 5.4.2. 
The NRC chose to develop the validation scheme with a benchmark based 
upon the modeling results, rather than the measurements. Please comment 
on the NRC's proposal and whether the justification is adequate.
    3. Please comment on the proposed quality metrics introduced in 
Section 5.4.7. Are these metrics appropriate for their intended 
purpose? Has the NRC presented an appropriate technical justification 
(see Sections 5.4.8 and 5.4.10) for the proposed metrics?
    4. Please comment on the feasibility of the proposed validation 
scheme. What initial (e.g., software and guidance development) and 
recurring (i.e., costs for each analysis) costs are foreseen for 
implementing the validation scheme?

    Dated at Rockville, Maryland, this 10th day of September, 2018.

    For the Nuclear Regulatory Commission.
Raj Iyengar,
Chief, Component Integrity Branch, Division of Engineering, Office of 
Nuclear Regulatory Research.
[FR Doc. 2018-19941 Filed 9-12-18; 8:45 am]
 BILLING CODE 7590-01-P