Text

OL - TVA Letter to NRC - 10-11-10_ASME Section XI Request for Relief WBN-PSI-1_NRC Copy.Pdf
	ML103090711
Person / Time
Site:	Watts Bar
Issue date:	10/12/2010
From:	; - No Known Affiliation
To:	; Division of Operating Reactor Licensing
References
	Download: ML103090711 (24)
	v • d • e

1 WBN2Public Resource From:

Boyd, Desiree L [dlboyd@tva.gov]

Sent:

Tuesday, October 12, 2010 9:21 AM To:

Wiebe, Joel; Raghavan, Rags; Milano, Patrick; Campbell, Stephen Cc:

Hamill, Carol L; Elton, Thomas L; Boyd, Desiree L

Subject:

TVA letter to NRC 11-10_ASME Section XI Request for Relief WBN-PSI-1_NRC copy.pdf Attachments:

10-11-10_ASME Section XI Request for Relief WBN-PSI-1_NRC copy.pdf Please see attached letter sent to the NRC today.

Thank You,

~*~*~*~*~*~*~*~*~*~*~*~*~*~*~

Désireé L. Boyd WBN2LicensingSupport SunTechnicalServices dlboyd@tva.gov 4233658764

~*~*~*~*~*~*~*~*~*~*~*~*~*~*~

Hearing Identifier:

Watts_Bar_2_Operating_LA_Public Email Number:

137 Mail Envelope Properties (7AB41F650F76BD44B5BCAB7C0CCABFAF16B07092)

Subject:

TVA letter to NRC 11-10_ASME Section XI Request for Relief WBN-PSI-1_NRC copy.pdf Sent Date:

10/12/2010 9:20:56 AM Received Date:

10/12/2010 9:21:36 AM From:

Boyd, Desiree L Created By:

dlboyd@tva.gov Recipients:

"Hamill, Carol L" <clhamill@tva.gov>

Tracking Status: None "Elton, Thomas L" <tlelton@tva.gov>

Tracking Status: None "Boyd, Desiree L" <dlboyd@tva.gov>

Tracking Status: None "Wiebe, Joel" <Joel.Wiebe@nrc.gov>

Tracking Status: None "Raghavan, Rags" <Rags.Raghavan@nrc.gov>

Tracking Status: None "Milano, Patrick" <Patrick.Milano@nrc.gov>

Tracking Status: None "Campbell, Stephen" <Stephen.Campbell@nrc.gov>

Tracking Status: None Post Office:

TVANUCXVS2.main.tva.gov Files Size Date & Time MESSAGE 313 10/12/2010 9:21:36 AM 10-11-10_ASME Section XI Request for Relief WBN-PSI-1_NRC copy.pdf 244817 Options Priority:

Standard Return Notification:

No Reply Requested:

No Sensitivity:

Normal Expiration Date:

Recipients Received:

Tennessee Valley Authority, Post Office Box 2000, Spring City, Tennessee 37381-2000 October 11, 2010 10 CFR 50.55a(g)(5)(iii)

U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Unit 2 NRC Docket No. 50-391

Subject:

Watts Bar Nuclear Plant (WBN) Unit 2 - American Society of Mechanical Engineers (ASME)Section XI Request for Relief WBN-2/PSI-1

Reference:

TVA letter dated January 29, 2008, Watts Bar Nuclear Plant (WBN) - Unit 2 -

Regulatory Framework for the Completion of Construction and Licensing Activities for Unit 2 Pursuant to 10 CFR 50.55a(g)(5)(iii), TVA is submitting a relief request for the WBN Unit 2 Preservice Inspection (PSI) Program.

One of the Actions Required for Licensing in Reference 1 stated, TVA plans to submit PSI related relief requests on or before September 24, 2010. This letter satisfies that action. provides relief request WBN-2/PSI-1, which requests relief from the ASME Section XI, Table IWB-2500-1, Examination Category B-A, Note 2, and Examination Category B-J, Note 4, requirements that the extent of examination includes essentially 100% of (the:

Exam Category B-A only) weld length. The definition of essentially 100% is provided by both NRC Information Notice 98-42, Implementation of 10 CFR 50.55a(g) Inservice Inspection Requirements, and Code Case N-460, Alternative Examination Coverage for Class 1 and Class 2 Welds,Section XI, Division 1, and requires examination coverage of more than 90 percent of the specified examination volume in lieu of essentially 100%.

Examination coverage of greater than 90 percent was not achieved for the welds listed in the proposed relief request and the applicable coverage percentage is specified in the relief request for each weld. The examination coverage achieved for the subject welds in conjunction with acceptable construction code examinations provides reasonable assurance that unallowable flaws do not exist in the subject component welds and that the welds are acceptable for service.

Thus, an acceptable level of quality and safety will have been achieved and public health and safety will not be endangered by allowing the proposed alternative examination coverage in lieu of the Code requirement.

U.S. Nuclear Regulatory Commission Page 3 October 11, 2010 bcc (Enclosures):

Stephen Campbell U.S. Nuclear Regulatory Commission MS 08H4A One White Flint North 11555 Rockville Pike Rockville, Maryland 20852-2738 Loren R. Plisco, Deputy Regional Administrator for Construction U. S. Nuclear Regulatory Commission Region II Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, Georgia 30303-1257 E1-1 TENNESSEE VALLEY AUTHORITY WATTS BAR NUCLEAR PLANT (WBN) UNIT 2 AMERICAN SOCIETY OF MECHANICAL ENGINEERS (ASME) SECTION XI REQUEST FOR RELIEF WBN-2/PSI-1

SUMMARY

In accordance with 10 CFR 50.55a(g)(5)(iii), TVA is requesting relief from the essentially 100%

code coverage required weld examination volume. This relief request addresses ASME Code Class 1 welds with the Examination Category and Item Numbers as specified in this relief request. The examination limitations described in this relief request are inherent to the component design and manufacture of the installed components given the original construction permit date for WBN Unit 2 of January 23, 1973.

NRC Information Notice 98-42, Implementation of 10 CFR 50.55a(g) Inservice Inspection Requirements, defined essentially 100% as more than 90 percent of the specified examination volume. In Code Case N-460, Alternative Examination Coverage for Class 1 and Class 2 Welds,Section XI, Division 1, the ASME provided the same definition.

1.0 SYSTEM/COMPONENTS FOR WHICH RELIEF IS REQUESTED The Class 1 components for which relief is requested are listed in Table 1 along with information related to materials of construction, configuration and NDE results.

2.0 APPLICABLE CODE EDITION AND ADDENDA The applicable ASME Section XI Code Edition and Addenda for WBN Unit 2 PSI is the 2001 Edition through 2003 Addenda as amended by 10 CFR 50.55a.

3.0 CODE REQUIREMENTS FROM WHICH RELIEF IS REQUESTED In accordance with 10 CFR 50.55(g)(5)(iii), relief is requested from the extent of examination requirements of essentially 100% for the following examination categories and item numbers from Table IWB-2500-1: B-A, B1.40 (note 2); B-J, B9.11 (note 4); B-J, B9.22 (note 4); and B-J, B9.31 (note 4). This relief request is applicable to the ultrasonic examination method associated with the subject examination categories and item numbers.

WBN Unit 2 has invoked ASME Section XI Code Case N-460, Alternative Examination Coverage for Class 1 and Class 2 Welds,Section XI, Division 1. Code Case N-460 states, in part, when the entire examination volume or area cannot be examined...a reduction in examination coverage...may be accepted provided the reduction in coverage for that weld is less than 10%.

E1-2 4.0 BASIS FOR RELIEF In accordance with 10 CFR 50.55a(g)(5)(iii), relief is requested on the basis that the Code required, Table IWB-2500-1, essentially 100% examination coverage is impractical due to physical obstructions and limitations imposed by design, geometry, or physical obstructions for the welds and associated components listed in Table 1.

ASME Section XI, IWB-2200, Preservice Examination, requires that preservice examination be extended to include essentially 100% of the pressure retaining welds in all Class 1 components; therefore, no alternate Class 1 welds are available for selection.

Compliance with the examination requirements of ASME Section XI would require significant modification of plant components to remove obstructions, redesign of plant systems/components, or replacement of components where geometry is inherent to the component design.

Weld profile sketches and coverage plots are included in the NDE reports attached to this relief request for the applicable welds in Table 1.

5.0 PROPOSED ALTERNATIVES WBN Unit 2 performed the ASME Section XI Code required preservice volumetric examinations listed in Table 1 to the maximum extent possible utilizing certified personnel with applicable Performance Demonstration Initiative (PDI) endorsements and approved procedures.

For Examination Category B-J piping welds listed in Table 1, the examination personnel and equipment were required to meet Appendix VIII requirements as implemented by the Electric Power Research Institute (EPRI) PDI and mandated by 10 CFR 50.55a. The shear wave examination of the applicable stainless steel welds listed in Table 1, where access was limited to one side and the piping thickness is greater than 0.500, was supplemented by a refracted longitudinal wave examination. For those welds in Table 1, where access was limited to one side and the piping thickness is 0.500 or less, a supplemental 70q shear wave was performed.

For the Examination Category B-A RPV head-to-flange weld, W08-09, listed in Table 1, the examination personnel and equipment were required to meet Article 4 of Section V, except that alternative examination Beam angles may be used, as specified in ASME Section XI, Mandatory Appendix I, I-2110(b). The Article 4,Section V examination was supplemented with an Appendix VIII qualified examination; however, no additional coverage was achieved or credited based on the Appendix VIII supplemental examination.

6.0 JUSTIFICATION FOR GRANTING RELIEF The welds listed in Table 1 were examined to the maximum extent possible utilizing certified personnel, qualified equipment, and approved procedures to meet the preservice acceptance standards of ASME Section XI 2001 Edition through 2003 Addenda.

Surface conditioning of the subject welds was performed to the extent necessary to preclude a reduction in coverage associated with weld crowns, weld shrinkage, and surface roughness.

E1-3 Welds SIF-D199-05 and SIF-D199-06 had recordable root geometry identified by volumetric examination. Weld SIF-D197-05 had a recordable, but acceptable surface indication 1/8 in length located on the outside diameter valve side at the weld toe identified by surface examination. These three welds have not been in service and were acceptable to the construction code standards for installation. The examinations performed on these welds for both construction code and the limited coverage preservice examination, greater than 70% coverage minimum, are sufficient to ensure structural adequacy of the subject welds.

These welds also met the ASME Section III NDE acceptance criteria associated with construction, which for Class 1 butt welds requires radiography. The construction code radiography, while providing additional assurance of the structural integrity of the subject welds, is not qualified in accordance with ASME Section XI, Appendix VIII, and cannot be credited for ASME Section XI coverage. Additionally, the welds listed in Table 1 will be subjected to an ASME Section III pressure test prior to initial plant startup.

ASME Section XI, IWB-2200, Preservice Examination, requires that preservice examination be extended to include essentially 100% of the pressure retaining welds in all Class 1 components; therefore, no alternate Class 1 welds are available for selection.

Compliance with the examination requirements of ASME Section XI would require significant modification of plant components to remove obstructions, redesign of plant systems/components, or replacement of components where geometry is inherent to the component design.

The examination coverage achieved for the subject welds in conjunction with acceptable construction code examinations provides reasonable assurance that unallowable flaws do not exist in the subject component welds and that the welds are acceptable for service.

Thus, an acceptable level of quality and safety will have been achieved and public health and safety will not be endangered by allowing the proposed alternative examination in lieu of the Code requirement.

7.0 IMPLEMENTATION SCHEDULE AND DURATION Upon approval by the NRC staff, TVA will implement the provisions of this relief request for the Preservice Inspection of WBN Unit 2.

TABLE 1 - ASME CODE CLASS 1 COMPONENTS System /

Component ID Materials (Configuration)

Category

/ Item No.

Dia. /

Thk.

Report Number Limited Scan %

Additional Information RCS /

RCF-C2-2 SA-351 CF-8A (pipe and pump)

B-J /

B9.11 27.5 /

2.21 R-P0147 75%

Beam angle: 45o refracted longitudinal Transducer Size:.5x1.0 Limitation upstream due to pump housing configuration.

NRI* (PT NRI*)

RCS /

RCF-C3-2 SA-351 CF-8A (pipe and pump)

B-J /

B9.11 27.5 /

2.21 R-P0149 75%

Beam angle: 45o refracted longitudinal Transducer Size:.5x1.0 Limitation upstream due to pump housing configuration.

NRI* (PT NRI*)

RCS /

RCF-D145-05 SA-403 WP304 (tee and reducer)

B-J /

B9.11 4 /

0.531 R-P0228 90%

Beam angle: 1) 45o shear and 2) 70o shear Transducer Size: 1).250 and 2).250 Limitation due to tee and reducer configuration.

NRI* (PT NRI*)

RCS /

RCF-D145-08 SA-403 WP304 /

SA-182 F316 (elbow/valve)

B-J /

B9.11 4 /

0.531 R-P0226 50%

Beam angle: 1) 45o shear and 2) 60o refracted longitudinal Transducer Size: 1).250 and 2) dual 8x14mm Limitation due to valve body taper.

NRI* (PT NRI*)

RCS /

RCF-G1-4 SA-351 CF-8A (pipe and pump)

B-J /

B9.11 31 /

2.48 R-P0152 75%

Beam angle: 45o refracted longitudinal Transducer Size:.5x1.0 Limitation downstream due to pump housing configuration.

NRI* (PT NRI*)

E1-4 TABLE 1 - ASME CODE CLASS 1 COMPONENTS System /

Component ID Materials (Configuration)

Category

/ Item No.

Dia. /

Thk.

Report Number Limited Scan %

Additional Information RCS /

RCF-G2-4 SA-351 CF-8A (pipe and pump)

B-J /

B9.11 31 /

2.48 R-P0156 75%

Beam angle: 45o refracted longitudinal Transducer Size:.5x1.0 Limitation downstream due to pump housing configuration.

NRI* (PT NRI*)

RCS /

RCF-G3-4 SA-351 CF-8A (pipe and pump)

B-J /

B9.11 31 /

2.48 R-P0150 75%

Beam angle: 45o refracted longitudinal Transducer Size:.5x1.0 Limitation downstream due to pump housing configuration.

NRI* (PT NRI*)

RCS /

RCF-G4-4 SA-351 CF-8A (pipe and pump)

B-J /

B9.11 31 /

2.48 R-P0155 75%

Beam angle: 45o refracted longitudinal Transducer Size:.5x1.0 Limitation downstream due to pump housing configuration.

NRI* (PT NRI*)

RCS /

RCS-1-6 SA-351 CF-8A /

SA-182 F316 (pipe/branch)

B-J /

B9.31 6 /

2.33**

R-P0101 50%

Beam angle: 45o refracted longitudinal Transducer Size:.5x1.0 Limitation from branch connection side due to configuration.

NRI* (PT NRI*)

RCS /

RCS-2-6 SA-351 CF-8A /

SA-182 F316 (pipe/branch)

B-J /

B9.31 6 /

2.33**

R-P0105 50%

Beam angle: 45o refracted longitudinal Transducer Size:.5x1.0 Limitation from branch connection side due to configuration.

NRI* (PT NRI*)

E1-5 TABLE 1 - ASME CODE CLASS 1 COMPONENTS System /

Component ID Materials (Configuration)

Category

/ Item No.

Dia. /

Thk.

Report Number Limited Scan %

Additional Information RCS /

RCS-3-6 SA-351 CF-8A /

SA-182 F316 (pipe/branch)

B-J /

B9.31 6 /

2.33**

R-P0106 50%

Beam angle: 45o refracted longitudinal Transducer Size:.5x1.0 Limitation from branch connection side due to configuration.

NRI* (PT NRI*)

RCS /

RCW-01 SA-351 CF-8A /

SA-182 F316 (pipe/branch)

B-J /

B9.31 4 /

2.21**

R-P0107 46%

Beam angle: 1) 45o shear and 2) 60o refracted longitudinal Transducer Size: 1).375 and 2) dual 8x14mm Limitation from pipe side due to configuration.

NRI* (PT NRI*)

RCS /

RCW-02 SA-351 CF-8A /

SA-182 F316 (pipe/branch)

B-J /

B9.31 4 /

2.21**

R-P0108 41%

Beam angle: 1) 45o shear and 2) 60o refracted longitudinal Transducer Size: 1).375 and 2) dual 8x14mm Limitation from pipe side due to configuration NRI* (PT NRI*)

RHRS /

RHRF-D031-04 SA-403 WP316 /

SA-182 F316 (tee/valve)

B-J /

B9.11 14 /

1.250 R-P0689 76%

Phased array 25o to 70o shear wave sector (16 element probe) and 40o to 70o refracted longitudinal wave sector (15 element probe supplemental)

Limitation due to valve to tee configuration.

NRI* (PT NRI*)

E1-6 TABLE 1 - ASME CODE CLASS 1 COMPONENTS System /

Component ID Materials (Configuration)

Category

/ Item No.

Dia. /

Thk.

Report Number Limited Scan %

Additional Information RHRS /

RHRF-D031-13 SA-376 TP316 /

SA-182 F316 (pipe/valve)

B-J /

B9.11 14 /

1.250 R-P0766 83%

Phased array 25o to 70o shear wave sector (16 element probe) and 40o to 70o refracted longitudinal wave sector (15 element probe supplemental)

Limitation due to valve to tee configuration.

NRI* (PT NRI*)

RHRS /

RHRF-D031-14 SA-403 WP316 /

SA-182 F316 (elbow/valve)

B-J /

B9.11 10 /

1.00 R-P0767 90%

Phased array 25o to 70o shear wave sector (16 element probe) and 40o to 70o refracted longitudinal wave sector (15 element probe supplemental)

Limitation due to valve to elbow configuration.

NRI* (PT NRI*)

RHRS /

RHRS-015 SA-403 TP316 /

SA-403 WP316 (pipe/tee)

B-J /

B9.11 10 /

1.00 R-P0759 88%

Phased array 25o to 70o shear wave sector (16 element probe)

Limitation from tee side configuration NRI* (PT NRI*)

RPV /

W08-09 SA-508 Cl2 (ring and flange)

B-A /

B1.40 173 /

7.30 R-P1014 75%

Beam angle: 1) 0o longitudinal 2) 45o shear and 3) 60o shear, Transducer Size: 1) 1, 2).5 x 1.0, and 3).5 x 1.0 Limitations from the flange profile configuration and three lifting lugs (4.0 tall x 5.9 length each and have a 12.8 arc length in contact with RPV head) see attached sketch (page E1-11)

NRI* (PT NRI*)

E1-7 TABLE 1 - ASME CODE CLASS 1 COMPONENTS System /

Component ID Materials (Configuration)

Category

/ Item No.

Dia. /

Thk.

Report Number Limited Scan %

Additional Information SIS /

SIF-B-T076-06 SA-376 TP304 /

SA-182 F316 (pipe/flange)

B-J /

B9.22 1.5 /

0.281 R-P0590 50%

Phased array 35o to 80o shear wave sector (8 element probe), Limitation from flange side configuration NRI* (UT only)

ML103090711

Text

Subject:

Subject:

Subject:

Reference:

SUMMARY

Navigation menu

Search