Nuclear Regulatory Commission · 2018. 9. 27. · PR.XC)R.I EY' ACCELERATEDRIDS'PROCESSING REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS) ACCESSION NBR:9501100166'OC.DATE: .95/01/06

PR.XC)R.I EY'ACCELERATED RIDS'PROCESSING

REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9501100166'OC.DATE: .95/01/06 NOTARIZED: NO DOCKET'FACIL:50-260 Browns Ferry Nuclear Power Station, Unit 2, Tennessee 05000260

AUTH.NAME AUTHOR AFFILIATIONSALAS,P. Tennessee Valley Authority

RECXP.NAME RECXPXENT AFFILIATIONDocument Control Branch (Document Control Desk).

SUBJECT: Forwards response to NRC .941114 ltr & provides add info resecond 10-yr interval ISI program.

DISTRIBUTION CODE: A047D COPIES RECEIVED:,LTR ENCL SIZE:TITLE: OR Submittal: Inservice/Testing/Relief from ASME Code — GL-89-04NOTES:

P

I IC

0',

RECIPIENTID CODE/NAME

PD2-4WILLIAMS,J.

INTERNAL: ACRS~"-IL - CEHTE . '0NRR/DE/EMEBOGC/HDS3

EXTERNAL: LITCO BROWN,B.NOAC

COPIESLTTR ENCL

1 11 1

6 61 11 11 0

1 11 1

RECIPIENTID CODE/NAME

PD2-4-PD

AEOD/SPD/RABNRR/DE/EMCBNUDOCS-ABSTRACTRES/DSIR/EIB

LITCO RANSOME I CNRC PDR

COPIESLTTR ENCL

1 1

1 11 11 11 1

1 11 1

'R

I

T'

0

C

E

N

NOTE TO ALL",RIDS" RE CI PI E NTS:PLEASE HELP US TO REDUCE iVASTE!CONTACTTHE DOCUhfENTCON fROLDESK, ROOhf Pl-37 (EXT. 504-2083 ) TO ELlhfINATEYOUR i'AifE FROifDISTRIBUTIONLISTS I:OR DOC!.:MEN fS YOU DON"I'L'ED!

TOTAL NUMBER OF COPIES REQUIRED: LTTR 20 ENCL 19

'Tennessee Valley Authority, Post Oiiice Box 2000, Decatu~, Alabama 35609

JAN O6 1995

U.S. Nuclear Regulatory CommissionATTN: Document Control DeskWashington, D.C. 20555

Gentlemen:

In the Matter OfTennessee Valley Authority

Docket No. 50-260

BROWNS FERRY NUCLEAR PLANT (BFN) — UNIT 2 — REPLY TO NRC 8REQUEST FOR ADDITIONAL 1NFORMATZON (RAZ) REGARDING THE SECOND10-YEAR ZNTERVAL INSERVZCE INSPECTZON (ISI) PROGRAM(TAC NO M89119)

The purpose of this letter is to respond to NRC'sNovember 14, 1994, RAI regarding the second 10-year intervalinservice inspection program. NRC requested TVA to clarifythe ISI program (2-SI-4.6.G), Section 8.1, note 6 regardingthe examination schedule for Class 1 equivalent (IWB)components. In addition, NRC requested information regardingexamination coverages specified for certain components listedin relief requests ISI 2-1, ISI 2-2, and ISI 2-4.Enclosure 1 contains specific details concerning the NRCrequested information.

Enclosure 2 contains the commitments contained in thisletter. If you have any questions please contact me atextension (205) 729-2636.

Since ly

Pe SalasManager of Site Licensing

Enclosurecc: See page 2

95011001hh 950106PDR ADOCK 050002609 PDR

U. S. Nuclear Regulatory Commission

fAV05 1995

Enclosurecc (Enclosure):

Mr. Mark S. Lesser, Section ChiefU.S. Nuclear Regulatory CommissionRegion II101 Marietta Street, NW, Suite 2900Atlanta, Georgia 30323NRC Resident. InspectorBrowns Ferry Nuclear PlantRoute 12, Box 637Athens, Alabama 35611

Mr. J. F. Williams, Project ManagerU.S. Nuclear Regulatory CommissionOne White Flint, North11555 Rockville PikeRockville, Maryland 20852

ENCLOSURE

TENNESSEE VALLEY AUTHORITYBROWNS FERRY NUCLEAR PLANT (BFN)

UNIT 2

TVA S REPLY TO NRC S NOVEMBER 14'994REQUEST FOR ADDITIONAL INFORMATION (RAI)

PURPOSE

The purpose of this enclosure is to provide TVA's reply to NRC'srequest for additional information dated November 14, 1994. Thefollowing is a restatement of the requested information followedby TVA's reply.NRC's Request Item 1

Clarification of Note 6. Section 8.1Zn Note 6 of Section 8.1, "Examination Schedule, Part 1 — Class 1Equivalent (IWB) Components," the program states:

Approximately 90~ of the B-J welds, within practical limits ofaccessibility, shall be examined during the life of the plant.All carbon steel or low alloy (similar) RPV nozzle-to-safe endwelds plus additional welds to comprise a 25~ sample shall beexamined each interval. All stainless or dissimilar metal weldsare examined under Examination Category B-F.

NRC's Request Item l.aClarify the meaning of this .note 'with respect to successiveexaminations. Are. the same B-J and B-F Category welds examinedeach interval? Are these welds examined on the same periodicschedule as performed during the previous interval?

TVA's Response Item l.aThe code of record for the second inspection interval for BFNUnit 2 is the 1986 Editi'on of the American Society of MechanicalEngineers (ASME) Boiler and Pressure Vessel Code, Section XI,Division 1 in accordance with 10 CFR 50.55a(g)(4). The extent ofexamination for Category. B-J (Pressure retaining welds in piping)is determined in accordance with the 1974 Code Edition, Summer1975 Addenda of ASME Section XI. The extent .of examination isdefined as the criteria for the selection of Class 1 B-J welds tobe .examined. The 1974 Code Edition, -Summer of 1975, Section .IWB-2420(c) requires examination of a similar percentage ofcomponents not previously inspected during earlier inspectionintervals. Periodic examination of Category B-J welds isaddressed in 2-SI-4.6.G paragraph 7.3.2.E(1), page 33.

Note six provides clarification to the examination schedule thatsimilar metal nozzle to nozzle safe-end welds (i.e., terminalends) are to be examined during each interval. Nozzle to nozzlesafe-end welds are supplemented with Category B-J piping weldsselected according to the 1974 Code Edition, Summer 1975 toensure 25 percent of examination Category B-J welds are scheduledfor examination during each inspection interval. Successiveexamination of the similar metal nozzle to nozzle safe-end weldssupplemented with Category B-J piping welds not previouslyexamined will result in examination of approximately 90 percentof the Category B-J piping welds during the course of fourinspection intervals.The extent of examination for Category B-F (dissimilar metalwelds) is determined in accordance with the ASME Section XI, 1986Code Edition. Category B-F welds are examined successively eachinspection interval and examined on the same periodic schedule asthe first inspection interval to the extent practical.NRC's Request Item 1.b

It is unclear what is meant by the description of RPVnozzle-to-safe end welds as being "low alloy (similar)," whenthese welds are, typically, dissimilar metal welds. Clarify thischaracterization.TVA's Response Item 1.b

The term "safe end" is utilized for both carbon steel systemswith carbon steel safe ends and stainless steel systems withstainless steel safe ends. The carbon steel safe end to nozzlewelds are similar metal welds and are classified as examinationcategory B-J weldments. The stainless steel safe end to nozzlewelds are dissimilar metal welds and are classified asexamination category B-F weldments.

ASME Section XI, 1986 Code Edition, Table IWB-2500-1, Note 3, forexamination Category B-F, pressure retaining dissimilar metalwelds describes the combination of materials that result indissimilar metal welds as: a) carbon or low alloy steels to highalloy steels; b) carbon or low alloy steels to high nickelalloys; or c) high alloy steels to high nickel alloys.NRC's Request Item 1.c.

The note states that all stainless or dissimilar metal welds areexamined under Category B-F. Provide justification for groupingall stainless steel welds in this Category.TVA's Response Item 1.c

Note 6 reference to stainless metal welds is incorrect. TVA willrevise 2-SI-4.6.G, note six to delete the reference to stainlesssteel welds, since Category B-F is applicable to only dissimilarmetal welds.

NRC's Request Item 2

"Re uest for Relief ISI-2-1 Reactor Pressure Vessel Su ortInte ral AttachmentThis request was previously granted in an NRC Safety EvaluationReport (SER) dated October 20, 1994, due to inaccessibility ofthe RPV support skirt weld. Two 24-inch sections of the outersurface of .the integral attachment weld, located approximately180'part, are accessible through access ports in the permanentinsulation. The licensee stated in the initial request. that eachof these areas would be examined by the required surfaceexamination method.

This request has now been revised to show that an ultrasonicexamination would be performed in lieu of the required surfacemethod. The Code allows a volumetric technique to be used as analternative to the surface method only when the configuration of'the integral attachment weld conforms to Figure INB-2500-14.However, the licensee's request lists IWB-2500-13 as theconfiguration of the RPV skirt weld at BFN-2."NRC's Request Item 2.a.

Submit a cross-sectional drawing of the BFN-2 attachment welddesign that shows how the ultrasonic examination will provideeffective surface coverage for this weld.TVA's Response Item 2.a

TVA is withdrawing relief request ISI-2-1.NRC's Request Item 2.b

Discuss the qualification plan for the ultrasonic technique.TVA's Response Item 2.b

See item 2.a above

E1-3


Re uest for Relief ISI-2-2: Reactor Pressure Vessel Threads inFlange

This request states that the configuration of the cladded sealingsurface, and the stud hole locations themselves, limitaccessibility to perform the volumetric examination toapproximately 684 of that required by the Code. InspectionReport R0034 was submitted to provide justification of theimpracticality due to poor accessibility. However, thehand-drawn sketch attached to R0034 does not clearly identify thegeometric restrictions that cause a reduced examination volume.Submit a detailed drawing that supports the argument for limitedaccessibility for the threaded areas of the flange.TVA's Response Item 3

Relief request ISI-2-2 is withdrawn. After further evaluation,TVA has determined that additional examination coverage may beobtained by using specialized search units which were notavailable during the time of the examinations. Smaller searchunits and those of an offset angle are needed in order to examinethe area between the reactor pressure vessel flange hole and theraised cladded seal area. The reactor pressure vessel flangehole and the raised cladded seal areas of limitation will beexamined during the second period of this interval along with thesecond period sample. The first period sample percentagecompleted for Code Category B-G-1 was 21 percent which is inaccordance with ASME Section XI Code,IWB-2412.


Re uest for Relief No. ISI-2-4: Class 1 and or Class 2 Pi inWelds

The table attached to ISI-2-4 specifically lists nine B-J and twoB-F Examination Category welds. No Class 2 welds are currentlyincluded in this request for relief. Provide a list of anyClass 2 (C-F-l or C-F-2 Category) welds for which relief is beingrequested, along with the proper justification for each, orrevise this relief request to include only Class 1 welds.TVA's Response Item 4

TVA has revised relief request ISI-2-4 (enclosed). The revisedrelief request deletes the reference to examination categoriesC-F-1 and C-F-2 (class 2 welds), since no limitations have beenidentified during the second ten year inspection interval.

E1-4

NRC's Request Item 4.a

Define the ultrasonic scan nomenclature used in the tableattached to ISI-2-4, i.e., what orientations and angles do scans1 through 5 represent?

TVA's Response Item 4.a

The ultrasonic scan nomenclature utilized in ISI-2-4 is depictedin Figure 1.The beam angles utilized during the examination are noted on theExamination Summary and Resolution Sheet and on the individualcalibration reports provided in the previous submittal for eachapplicable weld examined. The applicable scans are given thefollowing nomenclature: Scan 1, a visual exam to determine ifthe weld is amenable for ultrasonic examination; Scan 2, zerodegree base material scan, when applicable; Scan 3, an axial scanfrom the upstream side of the weld; Scan 4, an axial scan fromthe downstream side of the weld; Scan 5, a circumferential scanin the clockwise direction.NRC's Request Item 4.b

Please describe the method of computing the examinationcompletion percentages listed in this table.The volumetric coverage for the majority of the welds listed inthe attached table appears to be low, and the informationprovided for each is insufficient to justify relief. Outersurface contours and other geometric configurations that limiteach of these examinations must be described in sufficient detailto provide an acceptable basis for impracticality per10 CFR 50.55a(g)(6)(i). The drawings included in recentinspection reports do not support this conclusion, i.e., severalof the weld drawings appear to suggest increased accessibilitywith the application of specialized ultrasonic search units.TVA's Response Item 4.b

The method of computing weld examination completion percentagesis based on the following suppositions.

Welds with access from both sides (scans 3, 4, 5, 6) areequal scans for calculating examination volume. The formulaused is: 0.25(scan 3)+ 0.25 (scan 4) + 0.25 (scan 5)+ 0.25(scan 6).

2. For welds with access from one side due to configuration(e.g., pipe, valve) the axial scan (scan 3 or 4) will equal50% of the volume attained and the circumferential scans(scans 5 and 6) equal 50% combined. Use the formula:0.50(scan 3 or 4) + .25(scan 5) + 0.25(scan 6) = 1004.

3. Examination volume coverage may be increased by utilizationof high angle longitudinal wave techniques. Increasing theangle and the ability of L-waves to penetrate stainlesssteel weld material will increase the examination volumecoverage by the amount depicted on the exam coverage drawing(ASME Section XI Code, 1986 Edition, Appendix III, figureIII-3230-1).

4. Examination limitations must factor weld length into accountwhen an area is restricted due to lug attachments and otherinterferences. As an example, the following is given:a. weld length = 100 inches

b. length of interferences = 5 inches

5/100 = .05 or 54 reduction in coverage or 954 coverageof the weld length.

The ASME Section XI Code requires that the examination volume foreach weld must be determined in order to establish the requiredbeam path angles to maximize coverage and verify techniqueparameters. The following paragraphs explain the determinationof the Code required volumes, what constitutes a complete ASMESection XI examination for piping welds, the effects ofexamination limitations, and compliance with Code Case N-460,Alternate Examinations coverage for Class 1 and Class 2 weldsSection XI, Division 1.

The ASME Section XI required examination volume for each type ofpiping weld is shown in the IWB-2500 figures. The volumegenerally contains the weld and 1/4" on each side of the weld.The volume thickness contains (1/3 piping thickness) 1/3 (t) forthe length of the examination volume. The volume changes withvariations in weld configuration (e.g. transition betweendifferent pipe thickness). It is necessary to determine therequired volume for each group of similar welds to allow settingof scanner limits for automated examinations and scan paths formanual examinations. The ASME Section XI, 1986 Code Edition, NoAddenda, Section IWA-2232 states that piping weld required volumeshall be examined per ASME Section XI Appendix III requirements.Appendix III specifies the examination angles and scan directionsfor examining piping welds. It also specifies how theexaminations are to be performed.Variables such as weld preparation, weld crown width, or physicalinterference may preclude obtaining two-beam path directioncoverage of the complete examination volume with half-Vexamination from two sides as shown in Appendix III of the 1986Edition of the Code, Fig. III-3230-1. If this interference withexamination coverage occurs, the beam path is increased asrequired to obtain full coverage of the examination volume in two

E1-6

r

directions. Alternatively, the interference may be eliminated byone or more of the following:

Reducing the dimension of the wedge edge-to-beam entrypoint.

2. Reducing the search unit size.3. Increasing the beam angle.

4. Conditioning the weld surface.

Examination for reflectors parallel to. the weld seam is normallyperformed using a sufficiently long examination beam path toprovide coverage of the required examination volume in two-beampath directions. The examination is performed from two sides ofthe weld, where practicable, or from one side of the weld, as .aminimum. Examination for reflectors transverse to the weld seamsis normally performed on the weld crown on a single, scan path toexamine the weld root by one half-V path in two directions alongthe weld where crowns have been reduced allowing access. Ifaccess does not preclude examination on the crown due to loss ofcontact, then the beam path is increased to obtain full coverageby skewing the search unit suffice;ently to cover the weld rootarea.

ASME Section. XI Code Case N-460 defines the "essentially 1004 ofthe, weld length" statement in the IWB-2500-1. The Code Casestates that a reduction in coverage up to 10 percent ispermissible. ASME Section XI interpretation XI-1-89-32 furtherclarifies the Code Case by defining that the exclusion cannotexceed 104 when the limitations from all required scans arecombined additively. All of the required scans are thereforeequal in value. The equality of scans is used when calculatingthe effect(s) of limitations as well as determining compliancewith Code Case N-460.

Several items must be known about the weld being examined and theequipment used to perform the examination .before limitations andCode Case N-460 compliance can be calculated. These include therequired volume, as previously determined, the length of weldbeing examined, transducer offsets for automated exam equipment,and the length(s) of any .exam interference(s). Mostinterferences do not affect both sides of a weld. When bothsides are affected the effect is not equal. When a portion of aweld is partially examined, it is necessary to determine thestart and stop points for each scan. With these items known, i~tis possible to calculate the effect of a limited exam and whether"essentially,100< of the weld length" has been examined per CodeCase N-460.

NRC's Request Item 4.c

Provide a more detailed description of the limitation(s) for eachof the piping welds listed in the request.

TVA's Response Item 4.c

Relief request ISI-2-4 (enclosed) has been revised. The revisiondeleted four examination category B-Z welds and one examinationcategory B-F weld. Each weld contained in the revised reliefrequest is addressed individually with a more detaileddescription of the limitation(s) and justification for the. basisfor relief. The photographs contained in relief request ISI-2-4are BFN Unit 3 welds. BFN Unit 3 weld limitations are typical ofthe limitations encountered in BFN Unit 2. Photographs for BFNUnit 2 welds could not be obtained because of unit operation.The photographs are for information only. Welds deleted fromrelief request ISI-2-4 are listed below with a reason for thedeletion.Weld DRHR-2-12 — was not examined for ASME Section XI credit andis deleted from relief request ISI-2-4. DRHR-2-12 is notscheduled for examination during the second'en-year interval.Weld GMS-2-10-LS — Weld GMS-2-10-LS is a longitudinal seam weld.This weld is deleted from relief request ISI-2-4 based on NRCapproval of Code Case N-524 Alternative Examination Requirementsfor Longitudinal Welds in Class 1 and 2 Piping — Section XI,Division 1. Reference NRC's letter from Fredrick J. Hebdon toOliver Kingsley, Jr. dated September 28, 1994.Welds RWC-2»001-G002, RWCU-2»004-G073, and RWCU-2-004«G074 — arenew welds. They were installed during the Unit 2 Cycle 6refueling outage. They are being deleted from the revised reliefrequest ISI-2-4, since the construction code radiography servesas the preservice examination in accordance with IWB-2200(b).NRC's Request Item 5

Additional Re uests for ReliefPlease verify that no additional requests for relief are requiredat this time. If additional relief requests are required, pleasesubmit them for staff review.TVA'esponse Item 5

During the Unit 2 Cycle 7 refueling outage, TVA identified othercomponents with examination limitations. In accordance with10 CFR 50.55a (g)(5)(iv), TVA will submit any additional new orrevised inservice inspection relief rec{uests. Although10 CFR 50.55a (g)(5)(iv) does not require these relief requeststo be submitted until one year after the end of the current 10-year inspection interval (interval began May 24, 1992), TVAexpects to submit these relief requests within six months of thedate of this letter.

El-8

Figure 1SCANNING NOMENCLATURE ZDENTIFXCAYXON FOR PZPZNG

5

10

(Q14 13

: '6

Reference Arrow Flow f - Visual2- Base Material When Required3-f4 Angle Beamf&f7 0'eld and HAZ.

m nen

RE T F R RELIEF I I-2-4 (Unit 2)

Class 1 Piping Welds (refer to attached list)

Item Num er:

B-F and B-J

B5.130, B9.10, or B9.30

'In i n R ir men: ASME Section XI, Table IWB-2500-1, ExaminationCategories B-F and B-J piping welds greater than or equal toNPS 4-inch

f i f: In some cases it is not possible to perform the volumetricultrasonic examination from both sides of the weld due toconfiguration or permanent features such. as: piping supports;. orfire retardant insulation in the adjacent wall penetration. Alsoattached is a detailed description of the limitations for eachweld. listed and a summary of the scans performed.

Al em te Ins ection: None.

E1-10

WELD CODENUMBER CAT.

REQUEST FOR RELIEF ISI-2-4 (continued)

ITEM SIZE ISI CODENUMBER MAT'L. NPS DRAWING CONFIGURATION SCAN % REMARKS

DCS-2-03 B-J B9.11 SS 12 ISI-0271-C VALVETO BELLOWS 37.4 No scan 3 or 4,limited scans 5 and 6

DCS-2-12 B-J B9.11 SS 12 ISI-0271-C VALVETO BELLOWS 37.4 No scan 3 or 4,limited scans 5 and 6

TCS-2-422 B-F

GMS-2-10 B-J

B5.130 DM

B9.11 CS

12 ISI-0271-C PIPE TO VALVE 86.5

26 ISI-0222-C VALVETO PIPE 86

No scan 4, limitedscans 5 and 6;supplemented with45 degree search

No scan 3 andsurface restriction;scan 4 limited'cans5 and 6 limited

DRHR-2-03 B-J B9.11 SS 24 ISI-.0221-C VALVETOPENETRATION

52 Limited due tosurface contour;Scans 3, 4, 5, and 6,limited Scans 3 and 4supplemented with a

WELD CODENUMBER CAT.

DRHR-2-03 (Cont'd) 52 60 degree searchunit; Scans 5 and 6supplemented with a45 degree refractedlongitudinal wavesearch unit

REQUEST FOR RELIEF ISI-2-4 (continued)

ITEM SIZE ISI CODENUMBER MAT'L. NPS DRAWING CONFIGURATION SCAN % REMARKS

TRWCU-2-02 B-J B9.11 SS 4 ISI-0272-C VALVETO VALVE 52 . Obtain best scans 3and 4 andsupplemented scans 5and 6

E1-12

RE UEST FOR RELIEF ISI-2-4 continued

Weld Number Cd C . C~fi Scan % Examination Limitation Details

DCS-2-03 B-J Valve to Bellows 37.4 Basis for Relief

No axial scan from the upstream side of the weld(Scan 3) was performed due to a stainless steel valve(FCV-75-25). The combined effect of the valve surface

taper and the anisotropic nature of the static cast stainlessmaterial creates a scan limitation and prevents a scanfrom this side of the weld. No axial scan from thedownstream side of the weld (Scan 4) performed due toa bellows configuration. Search unit contact is lost bythe radius of curvature from the bellows side,Circumferential scan in the clockwise ( Scan 5) andcircumferential scan in the counter clockwise direction(Scan 6) are limited due to the weld to fittingjunction.Loss of contact of the search unit impedes obtaining codecoverage for scans 5 and 6. Scans 5 and 6 weresupplemented with a 45 degree refracted longitudinalwave search unit in order to maximize coverage. Thelimitations are noted on the ultrasonic examination datasheets provided with the original response. (Seeattached photograph of similar weld in Unit 3, DCS-3-03)

E1-13

RE UEST FOR RELIEF I I-2-4. continued

Weld Number C~d. ~C' Scan 0 Examination Limitation DetailsDCS-2-03 (Cont'd) B-J Valve to Bellows 37.4 Justification for Relief:

TVAperformed a surface and ultrasonic examination onaccessible areas of the 12 inch circumferential valve toflued head weld, DCS-2-03. The design configuration ofthe subject weld limits ultrasonic examination preventing100% code examination coverage.

Conclusion: Based on the above justification, it isconcluded that the code requirements are impractical.TVA's supplemental examinations provide an acceptablelevel of quality and safety.

El-14

7'

' E t" J4, I ~

I ~ 4 t'

~ P" ~J

'

JS

P

IJ

ls

T h fk

~

W

1

4 ~I

QC$ - gI

SQ

Ct

Ig

4

1

'ga.,( - V ',

V2 'g~

OC,S-R-e 5


Weld Number Cd C . ~fi Scan% Examination Limitation DetailsDCS-2-12 B-J Valve to Bellows 37.4 Basis for Relief

No axial scan from the upstream side of the weld(Scan 3) was performed due to a stainless steel valve(FCV 75-53). The combined effect of the valve surfacetaper and the anisotropic nature of the static cast stainlessmaterial creates a scan limitation and prevents a scanfrom this side of the weld. No axial scan from thedownstream side of the weld (scan 4) was performed dueto a bellows configuration. Search unit contact is lostby the radius of curvature from the bellows side.Circumferential scan in the clockwise (Scan 5) andcircumferential scan in the counterclockwise direction(Scan 6) are limited due to the weld to fittingjunction.


Weld Number CCC.C~A ~dtean d Examination Limitation DetailsDCS-2-12 (Cont'd) B-J Valve to Bellows 37.4 Loss of contact of the search unit impedes obtaining code

coverage for scans 5 and 6. Scans 5 and 6 weresupplemented with a 45 degiee refracted longitudinalwave search unit in order to maximize coverage andimprove attenuation loss by shear wave search units onweld metal. ( See attached photograph of similar weldin Unit 3, DCS-3-12)

Justification for Relief:

TVAperformed a surface and ultrasonic examination onaccessible areas of the 12 inch circumferential valve toflued head weld, DCS-2-12. The design configuration ofthe subject weld limits ultrasonic examination preventing100% code examination coverage.

Conclusion:

Based on the above justification, it is concluded that thecode requirements are impractical. TVA'ssupplemental examinations provide an acceptable level ofquality and safety.

E1-18

~ E I

4. r ~~ +0 I

~ ~ 4. 8'

~ wi

~ 0 ~

P ~

J ~ ~~ ~ '

~ ~

0 0, ~

g .„'

7

(

J

0~8-3-g4P

II p

+p l

v4 ')<

I,'. fl

hC-'8-)A


Weld Number

TCS-2-422 B-F Pipe to Valve

Cd C . ~Cd ~dd Can d

86.5

Examination Limitation Details

Basis for Relief:

No axial scan from the downstream side of the weld(Scan 4) performed due to a stainless steel valve (HCV-75-27). The combined effect of the valve surface taperand the anisotropic nature of the static cast stainlessmaterial creates a scan limitation and prevents a scanfrom this side of the weld. Circumferential scan in theclockwise direction (Scan 5) and circumferential scan inthe counter clockwise direction (Scan 6) are limited dueto the weld to fitting junction. Loss of contact of thesearch unit impedes obtaining code coverage for scans 5and 6. Scans 5 and 6 were supplemented with a 45degree refracted longitudinal wave search unit in order tomaximize coverage and improve attenuation loss by shearwave search units on weld metal. ( See attachedphotograph of similar weld in Unit 3, TCS-3-.422)


TVAperformed a surface and ultrasonic examination onaccessible areas of the 12 inch circumferential pipe tovalve weld, TCS-2-422. A high percentage of code

RE VEST FOR RELIEF ISI-2-4 continued

Weld Number Cd C . ~Cfi Scan % Examination Limitation Details

TCS-2-422 (Co'nt'd) B-F Pipe to Valve 86.5 coverage was obtained (86.5%). The designconfiguration of the subject weld limits ultrasonicexamination preventing 100% code examinationcoverage.

Conclusion:

Based on the above justification, it is concluded that thecode requirements are impractical. TVA's supplementalexaminations provide an acceptable level of quality andsafety.

E1-22

REFERENCE ORAKDRAVO E-245!J-IC.DRAVO E-2455-IC-~

Id)TEI THIS i%AV)Ml 6&El SIDES'ldl-207I-CALL SIGNETS

I4ATERZAL SPECZFZCA TZCVISl2o SCH. do SA XU deed CS

X 6d7s ml PALL 7'(l2o SCH. do ASIN A35d GR 304 SSI2 75 X dd7s m( VALL Tld(loo SCH do SA 3'R6 C9IO.75s X .593o m(. VALL nd(.loo SCH. do ASTN A35d CR 304 SSIO.75. X .593. mr. VALL W(.

FCV-75-53 ~X-0147~~ CDCS-2 I2~ 4FLED HEAD

DSCS 2-l68FLUED EKED

FC V-75-25~OCS-2-03

FLUEO %ADDSCS-2-I6AFLIED ~AD

AQK CC I (EOl)IVALENT)

O

i~@~ ~oO 0..%'e

k.TCS-2-42 I (OL)

HCV-75-27 +sgHCV-75-27-BC~S TA TM.ESSSTEEL

TCS-g-422

DCS-2-03-LS

DCS-2-04DCS-2-04-LSDSCS-2-0I

DCS-2- I2-LS~

DCS-2- l3~ ///+0

,9 p~Q

C~SoS

DCS-2- l3ASEE NOTE I

DSCS-2-Ol-LSDCS -2- l3A-LSL OSCS-2-02 DCS-2-07DSCS-2-02-LS SEE NOTE I

DCS-2- I3-LS

%+

rss s rrr-s-s+ HCV-75-55~ HCV-75-55-BC

STAINLESS STEELI L J

TCS-2-406

TCS-2-423

boa

DCS-2-07-LS~

DSCS-2-09DSCS-2-09-LS

~$4P+6r

DCS-2 I4~ W~Fl V-75-54FCV 75"54-BC

TCS"2-4IO

TCS 2 409 / Q TCS 2 407TSCS-2-405

I . TELOS DCS-2-07 AND DCS-2-l3AARE DRAVO SHOP TELOS.

2. PZPE SEOMENTS CONTAININO OM.Y QhELONOITLOINAL SEAH HILL BE IDENTIFIED ASI

(BASE HELD NO.)-LS-D (DOWNSTREAM)(BASE WELD NO.)-LS-U (UPSTREAM)

DXCS - N - N JACO ICJ.I TN

PIC '5NlI IISJ

OJ AIN ~ CCC CLNACN CJ ~ SS NJSNAOT, CJ Nary CCL CACNOI

O JS SO

litOOl ISN Af CCC CLN It IS iiACN LCSCCJAN sCLO TCCS l IJI&S. CCSNCcr NATIMALSslct

LNNLTTTm AAOOCArm

TBtEJSCE VAllEYANM7tllYCORE SPRAY

D~DRAVO FIELD HELD ~O NOOS~DRAVO SHOP HELD

T

*a, + *1

~S

C.

4

i

)I j

~t

. *s.

+C$ ~ 5 '44e<

lI

*~%

h

Y'~

J

'5

I

"Ppk

k

J

l

1'

il J Vw,

qh

Weld Number CdC.~Cfi Scan % Examination Limitation DetailsGMS-2-10 B-J Valve to Pipe Basis for Relief:

No axial scan from the upstream side of the weld( Scan 3) was performed due to valve (FCV-01-026).

The combined effect of the valve surface taper and theanisotropic nature of the static cast material creates alimitation and prevents scan from this side of the weld.An axial scan from the downstream side of the weld(Scan 4) was limited due to fire retardant insulationinside the penetration. Scan 4 was limited to a distanceof 1.9 inches from centerline for the 45 degree shear anda distance of 1.5 inches for the 60 degree shear.Scans 5 and 6 are limited due to the weld to fittingjunction. Loss of contact of the search unit impedesobtaining code coverage for the circumferential scan inthe clockwise direction (scan 5) and the circumferentialscan in the counter clockwise direction (Scan 6). (Seeattached photograph of similar weld in unit 3,GMS-3-10)

E1-25


Weld Number Cd C. ~Cfi Scan % Examination Limitation DetailsGMS-2-10 (Cont'd) B-J Valve to Pipe Justification for Relief:

TVAperformed a surface and an ultrasonic examinationon accessible areas of the 26 inch circumferential valveto pipe weld, GMS-2-10.

A hi h ercenta e of code covera e was obtained~86 o . The design configuration of the subject weldlimits ultrasonic examination preventing 100% codeexamination coverage. This limitation is due topermanent asbestos-type insulation installed inside thepenetration up to the subject weld. Removal requires: (1)a Design Change Notice to revise drawings depictingremoved insulation from the mechanical drywellpenetration assemblies, (2) a calculation to evaluate theimpact of the removed insulation, (3) the design andfabrication of special metal reflective insulation sectionsto replace removed insulation, (4) a work areaventilated tent to contain asbestos insulation, (5)insulation workers having to contend with therequirements of working in both a contaminated area (C-Zone) and an asbestos hazard area.

E1-26

Weld Number CCC.~C ~Scan d Examination Limitation Details

GMS-2-10 (Cont'd) B-J Valve to Pipe Conclusion:

Based on the above justification and hardship, it isconcluded that the code requirements are impractical.TVA's supplemental examinations and high percentage ofcoverage provides an acceptable level of quality andsafety.

E1-27

7

~ ~

~ ~

~ ~

tt I ~~

' tt ~ ~I

'~ I ~

I, I ~

~ IA

A I

A I ~ I

I I ~

A ~I

I, ~,

~, II, ~ ~ A

~ A

I A

I ~

~ ~

~ ~

rl ~

~ ~

~ ~

~ ~

~ I

77 ~

t ~ II III

~ I ~~ t

~ w'

~

~ I

~ ~

I

A

~ I ~tA I ~ I

'I

~ tAr7

7 I ~ I litII

~ 7 ~~ 7 ~

~ et

'i

$ I

,/If,

l

4 OPS- $ -)oC4

I

Il

F"p+g~'V~-

f

t

V

4,'

E

4N$-9- so

Weld Number Cd'C . C~d Scan % Examination Limitation Details

DRHR-2-03 Valve to Penetration 52 Basis for Relief:

An axial scan from the upstream side of the weld(Scan 3) is limited due to a stainless steel valve (FCV-74-53). The combined effect of the valve surface taperand the anisotropic nature of the static cast stainlessmaterial creates a scan limitation; however a best effortscan was performed from this side of the weld in orderto maximize coverage. A 60 degree search unit wasused to increase effective coverage. An axial scan fromthe downstream side of the weld (Scan 4) was limiteddue to a flued head penetration. Search unit scan area islimited by the penetration configuration. A 60 degreesearch unit was used to increase effective coverage. Acircumferential scan in the clockwise direction (Scan 5)and a circumferential scan in the counter clockwisedirection (scan 6) are limited due to the weld to fittingjunction. Loss of contact of the search unit impedesobtaining code coverage for Scans 5 and 6. Scans 5and 6 were supplemented with a 45 degree

El-30

Weld Number Cd Ci. C~fi Scan % Examination Limitation Details

DRHR-2-03 (Cont'd) B-J Valve to Penetration 52 refracted longitudinal wave search unit in order tomaximize coverage and improve attenuation loss by shearwave search units on weld metal. ( See attachedphotograph of similar weld in unit 3, DRHR-3-03)


TVA performed an ultrasonic examination on accessibleareas of the 24 inch circumferential valve to flued headweld, DRHR-2-03. The design configuration of thesubject weld limits ultrasonic examination preventing100% code examination coverage.

Conclusion:

Based on the above justification, it is concluded that thecode requirements are impractical. TVA's supplementalexaminations provide an acceptable level of quality andsafety.

E1-31

41a

~ ~

hoTElI . PIPE SEGNO 'AINTNG TTID LGRGITM)IhAL

SElWS )(ILL I ITlFIED ASI(BASE'ELD hO. s

El-32

DSRIR 2-08&S QQSRIR-2-OSA~- I@r

V DSNT-2-0$~ DSETR-2-05A~-29%-2-(3

rG rg

+ ~ yP k,QoRIR-2-X X

I ~su»»r m.RESIDUAL )EAT REeVAL

DSRIR-2-07-LS- IOS»»-f.of.L$.2~

OS'-2-07

()SABIR-2 06 LS

~ f»O ffLtfr gylCO $%Df t. Mffff PC5 ID t CDCt5 ffD IDD Q ~ ICD fit/tt4 tID KCD ~ CCD &l tfCNVCCCfttD It fO ff»D It CCWKCf ~ CM»Dff ICI.D fID ID% ~ ICDAfffCCICNII fCCflfftffDfDR CCDCCCf N1D TD.

ltO Al ICD5 M ~ CDD CKAI

5CD CC5D 5KVIS ~ CtACt'f ICUI. CTWCD MIDICDC~5 OClRO7 5VtfffffD lfttOICD CREST

8ROh'NS ERRY NUCL AR PLANUNIT ~~

RESIDUAL HEAT REMOVAL SYSTEMTIELO LOCATIDhIS

Otlltfs ftD Dlf1' IO 55 ~ » 5ocefD. ~ ~, Deft Ol OF'2 etICD»f5ffDa CDD

CCD ISI 022I-C

~ —4 ~

I II

J'I

l

I

I

~ '-"'I

5PPjP- s- e9I

V4 I ~ItII ~

1'

I'I'

I

eS oaHR-g~~

Weld Number CM C . ~fi Scan o Examination Limitation DetailsTRWCU-2-02 B-J Valve to valve 50 Basis for Relief:

Note: This weld was replaced prior to startup during theUnit 2, Cycle 6 outage due to the 69-580 valvereplacement.

TVA requests relief in order to maintain codepercentage requirements for the first period. Best effortaxial scan from the upstream side of the weld (Scan 3)performed from stainless steel valve side (69-579). Thecombined effect of the valve surface taper and theanisotropic nature of the static cast stainless materialcreates a scan limitation and prevents a meaningful scanfrom this side of the weld. Loss of search unit contactdue to fitting taper radius is a major contributor to thelimitation noted. Best effort axial scan from thedownstream side of the weld (Scan 4) performed fromstainless steel valve side (69-580). The combined effectof the valve surface taper and the anisotropic nature ofthe static cast stainless material creates a scan limitationand prevents a meaningful scan from this side of theweld. Circumferential scan in the clockwise direction

- (Scan 5) and a circumferential scan in the counterclockwise direction ( Scan 6) were supplemented with a45 degree refracted longitudinal wave search unit inorder to maximize coverage.

El-34

Weld Number CCC.~C Scan o Examination Limitation Details

TRWCU-2-02 (Cont'd) B-J Valve to valve 50 ( See attached photograph of similar weld in Unit 3,RWCU-3-004-002)


TVAperformed a surface and an ultrasonic examinationon accessible areas of the 4 inch circumferential valve tovalve weld, TRWCU-2-02.

~occlusion:

The design configuration of the subject weld limitsultrasonic examination preventing 100% codeexamination coverage. Based on the above justification,if is concluded that the code requirements areimpractical. TVA's supplemental examinations providean acceptable level of quality and safety.

El-35

~DRKC-2-078$ ~ NKC-2"07APEHETRA TNV X-IA~

QRKC-2-05lQRKC-2-058~~

~ FCV"69-002FCV-69-002-BC

~ OSRKC-2&6~ DSRKC-2-05 (OLJ

~ rJRKC-2-olx~NKC"2-048QRKC"2-OAA~~~ DSRKC-2-07X NKC-2-58

69-5ao69-580-ec

TRKCU-2-269-57969-579-ec~

re r23yS OSRKC-2-09 REFERENCE DRiTVl A7K395TVl l79335-f7TVl -2458- -AG >l f SUPPORT HlPE:THIS ORAKIHG Sf 'ERSEOES Cfof-207!5HATERIAL SPECEFIC 1TI'DNS

6' 0. 432'OH. K LL - SSSCH.'-eo A-976'i T 30AA-3f2. GRTP 90i SEAHLESSJA' 0.937'OH. K2'L - CS

,SCH. 80 1 33K Gl f (SEAHLESSJ8' 0.562 HOH. KlfL - CR SCH. IZG8' 0.599 HOH. KAf ' C4 SCH. foOHOTES:

ALL FIELD KELDS K RE HADE'Y TVla xa'RCRD-2-43 ASHE CC-f (Eof)IVAL:HTJO C

~-:>c:, g aeyji5I2 2222~

: 2 g 0@/@503 (OLJ

.-. I Io Q DSRKC-2-02~

n Cn P5:

CARBON sTEEL RCROS-Z-O I~RCROS-2-02

6xi'REDUCER

STAINLESS STEEL ~ (STllhLESSJ~ ~ Qfm~i~r RCRD-2-5f~~ g~~

)5-576-ac(PAINLESS)~ RCRD-2-

RCROS-2<

MR~~~~-2-44

RCRO-2-45TRCIC-2-oof~ ~ DRKC-2-6 >e xe'xi TEE—TRCIC-2-oofA~

e x 6 REDvcza

TRCIC-2-002~RCRO-2" 46~C 2

5 P Q$5KC- rr FCV-69-00fFCV-89-oof-BC

ORKC-2-03» osRKC---oa5.22 ~

-)C-

H9fee'.25252mO

F02X222

F1

DRKC-2-02~OSRKC-2-0 f~

5P QRKC-2-59I

5"( ~NKC-Z-of69-50069-500

2r 2 p'~ QRKC-ZW-BC

G)+p2

C3C3

COtI

C3

RE. CTOR COHTROL ROO UNIT, Ho.DR. VE HYDRAULIC KELO Ho.RE 'IRH LINE

H-36

FCV-7f -oloFcv-7f -ohio-ac~ ~

~TRCIC 2 004

RCRD-2 39~2Pn

DETAIL CRD RET(JRH LINENOZZLE CAPTRCIC 2-003~

N~B 22.UHI HO.

IO- FIELD WELDD'- SNOP HELD 256 222524. 2255. 5545 22OCCAVCT 2222252 5 f~05

REACTOR KATERCLEAN-UP lKVCSSGE YlffEYAWHRflY

NS NUC RP ANUNIT 2

RElCTOR KATER CLEAH UP. RCIC, AHO CROHYDR. RETtNH LINE KELO IDEHTIFIClTIOH

2' N 2222 22REACTOR CORE

ISOLATIQH COOL IH84

CA2224

2 )-'5F5Y+5

(fffc 5 22 N

E-EOC GLe

22II2 2 4-2-~ 2-222 22

II .

li

- 47ly

i

t~

'1 ~ h.%V+

fA

Cv'//

*AD

~

Q'

r

RC.Lt- 7- 44):. yo gI'

ENCLOSURE, 2

TENNESSEE VALLEY AUTHORITYBROWNS FERRY NUCLEAR PLANT (BFN)

L'IST OF COMMITMENTS

TVA will revise 2-SI.-4.6.G, note six to delete the referenceto stainless steel welds, since Category B-F is app'licableto only dissimilar metal welds. TVA expects to revise 2-SI-4.6.G by June 23, 1995.

The reactor pressure vessel flange hole and the raisedcladded seal areas of limitation will be examined during thesecond period of this interval along with the second periodsample.

Documents

Nuclear Regulatory Commission · 2018. 9. 27. · PR.XC)R.I EY' ACCELERATEDRIDS'PROCESSING REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS) ACCESSION NBR:9501100166'OC.DATE: .95/01/06