ML060950279

GALL AMP: XI.M3, Reactor Head Closure Studs (Audit Worksheet, GALL Report AMP)

ML060950279
Person / Time
Site:	Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date:	03/22/2006
From:	Morgan M NRC/NRR/ADRO/DLR/RLRC
To:	Office of Nuclear Reactor Regulation
morgan M NRR/NRC/DLR/RLRC, 415-2232
Shared Package
ML060950189	List: ML060950195 ML060950215 ML060950218 ML060950220 ML060950224 ML060950235 ML060950250 ML060950258 ML060950262 ML060950269 ML060950271 ML060950277 ML060950279 ML060950284 ML060950290 ML060950301 ML060950311 ML060950323 ML060950328 ML060950331 ML060950347 ML060950351 ML060950356 ML060950364 ML060950370 ML060950372 ML060950375 ML060950540 ML060950549 ML060950559 ML060950567 ML060950570 ML060950573 ML060950579 ML060950582 ML060950587 ML060950596 ML060950606 ML060950610 ML060950620 ML060950624 ML060950629 ML060950632 ML060950634 ML060950637 ML060950645 ML061000078 ML061000090 ML061000096 ML061000101 ... further results
References
%dam200611, TAC MC9668
Download: ML060950279 (3)

Text

XI.M3 Reactor Head Closure Studs 1

AUDIT WORKSHEET GALL REPORT AMP PLANT: ______________________________

LRA AMP: __________________________

REVIEWER: ______________________

GALL AMP: XI.M3, Reactor Head Closure Studs DATE: __________________________

Program Element Auditable GALL Criteria Documentation of Audit Finding Program Description A. This program includes (a) inservice inspection (ISI) in conformance with the requirements of the American Society of Mechanical Engineers (ASME), Code,Section XI, Subsection IWB (2001 edition, including the 2002 and 2003 Addenda), Table IWB 2500-1, and (b) preventive measures to mitigate cracking.

Consistent with GALL AMP: G Yes GNo Document(s) used to confirm Criteria:

Comment:

1. Scope of Program A. The program includes (a) ISI to detect cracking due to stress corrosion cracking (SCC) or intergranular stress corrosion cracking (IGSCC), loss of material due to wear, and coolant leakage from reactor vessel closure stud bolting for both boiling water reactors (BWRs) and pressurized water reactors (PWRs); and Consistent with GALL AMP: G Yes GNo Document(s) used to confirm Criteria:

Comment:

A B. (b) preventive measures of NRC Regulatory Guide 1.65 to mitigate cracking. The program is applicable to closure studs and nuts constructed from materials with a maximum tensile strength limited to less than 1,172 MPa (170 ksi)

(Nuclear Regulatory Commission [NRC] Regulatory Guide

[RG] 1.65).

Consistent with GALL AMP: G Yes GNo Document(s) used to confirm Criteria:

Comment:

2. Preventive Actions A. Preventive measures include avoiding the use of metal-plated stud bolting to prevent degradation due to corrosion or hydrogen embrittlement, and to use manganese phosphate or other acceptable surface treatments and Consistent with GALL AMP: G Yes GNo Document(s) used to confirm Criteria:

XI.M3 Reactor Head Closure Studs 2

stable lubricants (RG 1.65). Implementation of these mitigation measures is can reduce SCC or IGSCC, thus making this program effective.

Comment:

3.

Parameters Monitored/

Inspected A. The ASME Section XI ISI program detects and sizes cracks, detects loss of material, and detects coolant leakage by following the examination and inspection requirements specified in Table IWB-2500-1.

Consistent with GALL AMP: G Yes GNo Document(s) used to confirm Criteria:

Comment:

4. Detection of Aging Effects A. The extent and schedule of the inspection and test techniques prescribed by the program are designed to maintain structural integrity and ensure that aging effects will be discovered and repaired before the loss of intended function of the component. Inspection can reveal cracking, loss of material due to corrosion or wear, and leakage of coolant. The program uses visual, surface, and volumetric examinations in accordance with the general requirements of Subsection IWA-2000. Surface examination uses magnetic particle, liquid penetration, or eddy current examinations to indicate the presence of surface discontinuities and flaws. Volumetric examination uses radiographic or ultrasonic examinations to indicate the presence of discontinuities or flaws throughout the volume of material. Visual VT-2 examination detects evidence of leakage from pressure-retaining components, as required during the system pressure test. Components are examined and tested as specified in Table IWB-2500-1.

Examination category B-G-1 for pressure-retaining bolting greater than 2 in. diameter in reactor vessels specifies volumetric examination of studs in place, from the top of the nut to the bottom of the flange hole, and surface and volumetric examination of studs when removed. Also specified are volumetric examination of flange threads and visual VT-1 examination of surfaces of nuts, washers, and bushings. Examination category B-P for all pressure-Consistent with GALL AMP: G Yes GNo Document(s) used to confirm Criteria:

Comment:

XI.M3 Reactor Head Closure Studs 3

retaining components specifies visual VT-2 examination of all pressure-retaining boundary components during the system leakage test and the system hydrostatic test.

5. Monitoring and Trending A. The Inspection schedule of IWB-2400, and the extent and frequency of IWB-2500-1 provide timely detection of cracks, loss of material, and leakage.

Consistent with GALL AMP: G Yes GNo Document(s) used to confirm Criteria:

Comment:

6.

Acceptance Criteria A. Any indication or relevant condition of degradation in closure stud bolting is evaluated in accordance with IWB-3100 by comparing ISI results with the acceptance standards of IWB-3400 and IWB-3500.

Consistent with GALL AMP: G Yes GNo Document(s) used to confirm Criteria:

Comment:

7. Corrective Actions A. Repair and replacement are performed in conformance with the requirements of IWB-400 and IWB-7000, respectively, and the material and inspection guidance of RG 1.65. As discussed in the appendix to this report, the staff finds the requirements of 10 CFR Part 50, Appendix B, acceptable to address the corrective actions.

Consistent with GALL AMP: G Yes GNo Document(s) used to confirm Criteria:

Comment:

8.

Confirmation Process A. Site quality assurance (QA) procedures, review and approval processes, and administrative controls are implemented in accordance with the requirements of 10 CFR Part 50, Appendix B. As discussed in the appendix to this report, the staff finds the requirements of 10 CFR Part 50, Appendix B, acceptable to address the confirmation process and administrative controls.

Consistent with GALL AMP: G Yes GNo Document(s) used to confirm Criteria:

Comment:

9.

Administrativ e Controls A. See Item 8, above.

Consistent with GALL AMP: G Yes GNo Document(s) used to confirm Criteria:

Comment:

10. Operating Experience A. The SCC has occurred in BWR pressure vessel head studs (Stoller 1991). The aging management program (AMP) has provisions regarding inspection techniques and Consistent with GALL AMP: G Yes GNo Document(s) used to confirm Criteria:

XI.M3 Reactor Head Closure Studs 4

evaluation, material specifications, corrosion prevention, and other aspects of reactor pressure vessel head stud cracking. Implementation of the program provides reasonable assurance that the effects of cracking due to SCC or IGSCC and loss of material due to wear will be adequately managed so that the intended functions of the reactor head closure studs and bolts will be maintained consistent with the current licensing basis (CLB) for the period of extended operation.

Comment:

XI.M3 Reactor Head Closure Studs 5

EXCEPTIONS Item Number Program Elements LRA Exception Description Basis for Accepting Exception Documents Reviewed (Identifier, Para.# and/or Page #)

1.

2.

Y ENHANCEMENTS Item Number Program Elements LRA Enhancement Description Basis for Accepting Enhancement Documents Reviewed (Identifier, Para.# and/or Page #)

1.

2.

Y DOCUMENT REVIEWED DURING AUDIT Document Number Identifier (number)

Title Revision and/or Date

1.

2.

3.

4.

Y.