ML111600250

Steam Generator Tube Inspection Report - Technical Specification 5.6.6.2.4

ML111600250
Person / Time
Site:	Beaver Valley
Issue date:	06/09/2011
From:	Harden P A FirstEnergy Nuclear Operating Co
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
L-11-148
Download: ML111600250 (8)

Text

FENOC ........ FirstEnergy Nuclear Operating Company Paul A. Harden Site Vice President June 9, 2011 L-11-148 ATTN: Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001

SUBJECT:

Beaver Valley Power Station, Unit No.2 Docket No. 50-412, License No. NPF-73 Beaver Valley Power Station P.O. Box 4 Shippingport, PA 15077 724-682-5234 Fax: 724-643-8069 Steam Generator Tube Inspection Report -Technical Specification 5.6.6.2.4 In accordance with Technical Specification 5.6.6.2.4, FirstEnergy Nuclear Operating Company hereby submits a report containing tube inspection results for Beaver Valley Power Station, Unit No.2, steam generators.

The enclosed report provides information required by the technical specification that was obtained during inspections conducted during the spring 2011 refueling outage. There are no regulatory commitments contained in this letter. If there are any questions or if additional information is required, please contact Mr. Thomas A. Lentz, Fleet Licensing, at (330) 761-6071.

Paul A. Harden

Enclosure:

Unit #2 -2R15 Steam Generator F* (F Star) Report cc: NRC Region I Administrator NRC Resident Inspector NRC Project Manager Director BRP/DEP Site BRP/DEP Representative FIRST ENERGY NUCLEAR OPERATING COMPANY Technical Services Engineering Department Nuclear Engineering ProgramsSection Issue Date: May 13, 2011

Subject:

Unit #2" 2R15 Steam Generator F* (F Star) Report Prepared by:

__ SG Program Owner, Date: 0 s I , 3/ II Reviewed by: Jeff <<3 --' Date:

Approved by: Doug Reeves o<J..--t.-

==-Date: S-/I?:> / 1/ Manager, Technical Services UNIT #2 -2R15 STEAM GENERATOR F* (F STAR) REPORT Pursuant to Specification 5.6.6.2.4 of the Technical Specifications, the following information is to be transmitted to the NRC within 90 days after entering MODE 4 following an outage in which the F* (F Star) methodology was implemented.

For 2R 15, MODE 4 occurred on April 7th, 2011. Therefore, this information must be submitted to the NRC on or before July 6, 2011. Per Specification 5.6.6.2.4, the following information is to be submitted and is discussed within this document: (a) The total number of indications, the location of each indication, the orientation of each indication, the severity of each indication and whether the indications initiated from the inside or outside surface, (b) The cumulative number of indications detected in the tubesheet region as a function of elevation within the tubesheet, (c) The projected end-of-cycle accident induced leakage from tubesheet indications.

During the 2R 15 outage, the Plus Point probe was utilized to inspect the top of tubesheet region. The 2R 15 inspection scope was 100% of the inservice hot leg tubes in all three steam generators (SG's) plus a 20% random sample of the inservice cold leg tubes in SG "A". The inspection distance in either leg was from 6.0 inches above the top of tubesheet to 3.0 inches below the top of tubesheet and bounds the required F* examination distance (Le. the expanded portion of the tube below the bottom of roll expansion transition) of 2.22 inches below the bottom of the expansion transition.

A small number of tubes (10 total in the hot leg of all 3 SG's and 4 in SG "A" cold leg) have roll expansion transitions at lower than nominal elevations.

These particular tubes were inspected to a depth of 5.0 inches below the top of tubesheet to ensure that the F* distance was adequately examined.

As seen from the information contained within, the morphology for the vast majority of the indications reported from the hot leg tubesheet region is believed to be attributed to circumferentially oriented outside diameter stress corrosion cracking (ODSCC). This is based on signal recognition and location of the reported indications.

All ODSCC indications observed were plugged upon detection.

All top of tubesheet circumferential indications were stabilized prior to installing the hot leg plug. None of the indications that were removed from service during 2R15 represented a (Cycle 15) leakage potential at postulated main steam line break (MSLB) conditions.

The information provided on the following pages summarizes the degradation observed during the 2R15 tubesheet region examinations.

The data has been analyzed utilizing the 300 kHz channel from the Plus Point probe. This provides the most accurate sizing technique and is used for assessing the severity of the indications.

Page 2 of7 SG "A" Hot Leg Tubesheet:

Twenty tubes were plugged for indications reported during the hot leg tubesheet region examination.

Of these tubes; nineteen tubes were reported with either single or multiple circumferential OOSCC indications located at or slightly below the top of tubesheet and one tube was reported with single axial OOSCC indication located above the top of tubesheet.

SG "A" Cold Leg Tubesheet:

No indications were reported during the 20% random sample inspection of the cold leg tubesheet region. 2RCS-SG21A 2R15 Tubesheet Indications Indication Location Orientation**

SG Row Column Elevation* A 6 50 TSH -0.12" A 8 38 TSH -0.03" A 8 57 TSH -0.09" A 9 23 TSH -0.08" A 11 38 TSH -0.14" A 12 37 TSH -0.15" A 12 41 TSH -0.09" A 12 42 TSH +0.00" A 13 44 TSH -0.07" A 19 55 TSH -0.20" A 20 21 TSH -0.13" A 25 33 TSH -0.08" A 27 72 TSH -0.05" A 33 33 TSH -0.06" A 38 49 TSH +0.49" A 40 43 TSH -0.05" A 41 49 TSH -0.10" A 42 42 TSH -0.07" A 42 45 TSH -0.01" A 43 47 TSH -0.01"

• TSH -Top of Tubesheet (Hot Leg) ** MCI -Multiple Circumferential Indications SAl -Single Axial Indication SCI -Single Circumferential Indication

• • • Reported Using the 300 kHz Plus Point Coil Volts SCI 0.12 SCI 0.18 SCI 0.16 SCI 0.21 SCI 0.13 SCI 0.20 SCI 0.13 SCI 0.17 SCI 0.19 MCI 0.13 SCI 0.14 SCI 0.24 SCI 0.20 MCI 0.17 SAl 0.12 MCI 0.27 SCI 0.16 SCI 0.17 SCI 0.07 SCI 0.08 Page 3 of7 Severity***

Axial Length 0.17" Initiation Arc Surfacel Projected Length Degradation Leakage 65 u OOSCC 0 110 u OOSCC 0 123 0 OOSCC 0 132 0 OOSCC 0 33 u OOSCC 0 59 u OOSCC 0 82 u OOSCC 0 69 u OOSCC 0 69 0 OOSCC 0 190 u OOSCC 0 98 u OOSCC 0 91 u OOSCC 0 155 0 OOSCC 0 130 u OOSCC 0 OOSCC 0 229 u OOSCC 0 50 u OOSCC 0 106 u OOSCC 0 107 0 OOSCC 0 34 u OOSCC 0 SG "8" Hot Leg Tubesheet:

Twenty four tubes were plugged for indications reported during the hot leg tubesheet region examination.

Of these tubes; twenty one tubes were reported with either single or multiple circumferential ODSeC indications located at or slightly below the top of tubesheet and three tubes were reported with single axial ODSee indications located above the top of tubesheet.

2RCS-SG21B 2R15 Tubesheet Indications Indication Location Orientation**

SG Row Column Elevation*

B 7 41 TSH+O.OO" B 8 32 TSH -0.01" B 8 54 TSH -0.04" B 9 54 TSH -0.12" B 11 19 TSH +0.00" B 11 46 TSH -0.08" B 11 47 TSH +0.00" B 12 57 TSH -0.12" B 15 53 TSH -0.06" B 16 32 TSH -0.12" B 17 9 TSH -0.08" B 17 24 TSH -0.08" B 17 38 TSH -0.10" B 18 49 TSH -0.10" B 20 33 TSH -0.09" B 21 24 TSH +0.04" B 21 25 TSH +0.01" B 21 44 TSH -0.11" B 22 14 TSH -0.09" B 25 26 TSH +0.14" B 32 51 TSH -0.09" B 32 56 TSH +0.00" B 37 51 TSH -0.11" B 38 56 TSH -0.09"

• TSH -Top of Tubesheet (Hot Leg) ** MCI -Multiple Circumferential Indications SAl -Single Axial Indication SCI -Single Circumferential Indication

• • • Reported Using the 300 kHz Plus Point Coil Volts SCI 0.19 SCI 0.10 MCI 0.29 SCI 0.18 SCI 0.12 SCI 0.19 MCI 0.21 SCI 0.20 SCI 0.19 SCI 0.14 SCI 0.16 SCI 0.11 SCI 0.24 SCI 0.28 SCI 0.15 SAl 0.31 SAl 0.15 SCI 0.13 SCI 0.10 SAl 0.10 MCI 0.10 SCI 0.12 SCI 0.08 SCI 0.13 Page 4 of7 Severity***

Axial Length 0.28" 0.16" 0.23" Initiation Arc Surfacel Projected Length Degradation Leakage 87 u OOSCC 0 47 u OOSCC 0 219 u OOSCC 0 75 u OOSCC 0 27 0 OOSCC 0 61 u OOSCC 0 161 u OOSCC 0 68 u OOSCC 0 44 u OOSCC 0 124 0 OOSCC 0 80u OOSCC 0 34 u OOSCC 0 75 u OOSCC 0 134 u OOSCC 0 27 u OOSCC 0 OOSCC 0 OOSCC 0 41 u OOSCC 0 59 u OOSCC 0 OOSCC 0 267 u OOSCC 0 58 u OOSCC 0 27 u OOSCC 0 70 u OOSCC 0 SG "C" Hot Leg Tubesheet:

Seven tubes were plugged for indications reported during the hot leg tubesheet region examination.

Of theses tubes; six tubes were reported with either single or multiple circumferential OOSCC indications located at or slightly below the top of tubesheet and one tube was reported with a single axial OOSCC indication located above the top of tubesheet.

2RCS-SG21C 2R15 Tubesheet Indications Indication Location Orientation**

SG Row Column Elevation1o C 3 46 TSH -0.17" C 8 57 TSH -0.06" C 8 58 TSH +0.12" C 9 92 TSH -0.16" C 11 53 TSH -0.03" C 20 57 TSH -0.07" C 35 61 TSH -0.09"

• TSH -Top of Tubesheet (Hot Leg) 1o1o MCI -Multiple Circumferential Indications SAI-Single Axial Indication SCI -Single Circumferential Indication

• • 1o Reported Using the 300 kHz Plus Point Coil Volts SCI 0.09 SCI 0.20 SAl 0.20 SCI 0.08 SCI 0.18 SCI 0.06 MCI 0.19 Page 5 of7 Severity101o1o Axial Length 0.16" Initiation Arc Surfacel Projected Length Degradation Leakage 47 u OOSCC 0 155 u OOSCC 0 OOSCC 0 30 u OOSCC 0 36° OOSCC 0 33 u OOSCC 0 67 u OOSCC 0 Non Tubesheet Region Degradation:

The following information lists the tubes that were removed from service for degradation in other areas of the steam generators.

This information is being submitted for completeness of the tube plugging performed 2R15 and is not required to be reported by Technical Specification 5.6.6.2.4.

2RCS-SG21A Indication Location Severity *** Initiation Orientation**

Axial Arc Surfacel Projected SG Row Column Elevation*

Volts Length Length Degradation Leakage A 7 37 4H -0.10" SAl 0.16 0.26" OOSCC 0 A 8 25 2H -0.26" SAl 0.13 0.31" OOSCC 0 A 16 8 3H -0.04" SAl 0.11 0.23" OOSCC 0 A 16 9 2H +0.14" SAl 0.12 0.41" OOSCC 0 A 16 24 6H -0.05" SAl 0.16 0.31" OOSCC 0 2RCS-SG21B Indication Location Severity *** Initiation Orientation**

Axial Arc Surfacel Projected SG Row Column Elevation*

Volts Length Length Degradation Leakage B 1 33 3H +0.18" SAl 0.10 0.45" OOSCC 0 B 6 31 3H +0.09" SAl 0.10 0.45" OOSCC 0 B 6 35 3H -0.02" SAl 0.16 0.33" OOSCC 0 B 6 42 2H +0.16" MAl 0.16 0.40" OOSCC 0 B 8 35 6H +0.05" SAl 0.11 0.16" OOSCC 0 B 10 32 3H +0.01" SAl 0.10 0.32" OOSCC 0 B 11 55 2H +0.00" SAl 0.09 0.17" OOSCC 0 B 11 59 2H +0.10" SAl 0.09 0.37" OOSCC 0 B 11 60 3H +0.06" SAl 0.08 0.34" OOSCC 0 B 13 72 3H +0.04" SAl 0.08 0.28" OOSCC 0 B 14 55 2H +0.10" SAl 0.18 0.52" OOSCC 0 B 15 66 3H -0.04" SAl 0.07 0.16" OOSCC 0 B 16 12 4H +0.00" SAl 0.16 0.28" OOSCC 0 B 16 14 3H +0.01" SAl 0.34 0.28" OOSCC 0 B 17 34 6H +0.17" SAl 0.10 0.29" OOSCC 0 B 18 31 2H +0.06" SAl 0.12 0.16" OOSCC 0 B 18 67 3H +0.08" SAl 0.11 0.23" OOSCC 0 B 20 34 2H -0.14" SAl 0.13 0.61" OOSCC 0 B 29 57 2H +0.00" SAl 0.07 0.23" OOSCC 0 B 31 17 2H -0.18" SAl 1.15 0.20" PWSCC 0 Page 6 of7 2RCS-SG21C Indication Location Severity *** Initiation Orientation**

Axial Arc Surfacel Projected SG Row Column Elevation*

Volts Length Length Degradation Leakage C 3 55 8C +0.04" SAl 0.21 0.21" OOSCC 0 C 15 29 4H +0.00" SAl 0.31 0.21" OOSCC 0 C 15 29 6H +0.00" SAl 0.13 0.26" OOSCC 0 C 29 12 VARIOUS PVN See Below 0 C 30 74 4H -0.03" SAl 0.17 0.42" OOSCC 0 C 31 59 6H +41.53" SCI 0.37 26 u OOSCC 0 C 31 63 3H +0.12" SAl 0.11 0.17" OOSCC 0 C 31 63 4H +0.07" SAl 0.07 0.16" OOSCC 0

• 2H, 3H, 4H, 6H -2 nd , 3 m , 4th, 6 th Hot Leg Tube Support Plate (Flow distribution baffle is referred to as 1 H/1 C) 8C -8 th Cold Leg Tube Support Plate ** MAl -Multiple Axial Indications PVN -Permeability Variation SAI-Single Axial Indication SCI -Single Circumferential Indication

• • • Reported Using the 300 kHz Plus Point Coil R29 C12 -This tube exhibited permeability variations ranging from 0.16 volts to 11.58 volts between the 7 th hot leg tube support plate and the 4th cold leg tube support plate. The bobbin probe (200 kHz) was used to verify that no axial OOSCC was present at the tube support plate intersections.

The bobbin probe (100 kHz) was used to verify that no axial OOSCC was present in the free span regions. A magnetically biased Plus Point probe was used to verify that no circumferential OOSCC was present at free span dings which may have represented a structural or leakage potential.

A full length in-situ pressure test was subsequently performed on the tube. No leakage or burst was observed at any of the test pressures.

Post in-situ bobbin probe testing showed no detectable degradation at the tube support plate intersections or in the free span regions. The tube was stabilized on the hot leg side prior to removing it from service via plugging.

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