ML20215L952

Requests Relief from 10-yr Inservice Insp Interval. Supportive Info for Relief Request from Specific 1977/ Summer,1979 Edition/Addenda of ASME Section XI Code Requirements Encl.Fee Paid

ML20215L952
Person / Time
Site:	Point Beach
Issue date:	10/27/1986
From:	Fay C WISCONSIN ELECTRIC POWER CO.
To:	Harold Denton, Lear G Office of Nuclear Reactor Regulation
References
CON-NRC-86-102 VPNPD-86-432, NUDOCS 8610290386
Download: ML20215L952 (31)

Text

.

Wisconsin Electnc mcwmr 231 W. MICHIG AN, P O. BOX 2046, MILWAUKEE.W153201 (414)277-2345 VPNPD-86-432 NRC-86-102 October 27, 1986 Mr. H. R. Denton, Director Office of Nuclear Reactor Regulation U. S. NUCLEAR REGULATORY COMMISSION Washington, D. C. 20555 Attention: Mr. George Lear, Director PWR Project Directorate 1 Gentlemen:

DOCKETS 50-266 AND 50-301 ASME SECTION XI, RELIEF REQUESTS

- POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 In accordance with 10 CFR 50.55a(g)(5)(iii), Wisconsin Electric Power Company (licensee) requests inservice inspection relief for the second ten-year inspection interval for Point Beach Nuclear Plant, Units 1 and 2.

Attachment 1 provides the supportive information for the relief request from specific 1977/ Summer, 1979 Edition / Addenda of ASME Section XI code requirements for Unit 1. Attachment 2 provides the supportive information for the relief request from specific ASME Section XI code requirements for Unit 2. Wisconsin Electric requests that the Commission review these relief requests and provide approval as required by the Commission's regulations.

! Enclosed is a check in the amount of $150 for the l application fee required by 10 CFR Part 170.

l l Please contact us if any additional information is needed.

Very trul ours, C. W. Fy Vice Presi ent Nuclear Power /

Enclosures (Check 928681)

Copy to Resident Inspector 0] h l

ATTACHMENT 1 UNIT 1 RELIEF REQUEST Relief Request No. Description RR-1-12 Regenerative Heat Exchanger Class 1 Shell and Nozzle Welds

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RR-1-12 Component Regenerative Heat Exchanger Exam Area Class 1 Tubesheet to Shell Welds Class 1 Nozzle to Shell Welds Isometric or Component Drawing Fig. A-7 ASME Section XI Category .

B-B B-D ASME Section XI Item Number B2.60 B3.150 ASME Section XI Examination Requirement A volumetric examination of 100% of all tubesheet welds and nozzle welds during the second 10 year interval.

Alternative Examination A volumetric examination of accessible portions of all tubesheet welds and nozzle welds equivalent to one of the three identical sections of the regenerative heat exchanger during the second 10-year interval.

Reason for Limitation The regenerative heat exchanger (RHE) provides the major single source of .

radiation exposure accumulated during a nominal refueling outage inservice inspection project. The " regenerative heat exchanger" is actually three shell-and-tube heat exchangers connected in series. The RHE is designed to recover heat from the reactor coolant system letdown stream by reheating the charging stream during normal operation. The letdown stream flows through the shell of the RHE and the charging stream flows through the tubes.

To ensure adequate coverage of the component welds with a minimum of exposure, the multiple stream concept should be carried out in all the examination catagories. Currently only one of three Class 1 cap-to-shell welds, Class 2 cap-to-shell welds, Class 2 tubesheet-to-shell welds, and two of six Class 2 nozzle-to-shell welds are examined in accordance with allowances in IWB-2500 and IWC-2500 of ASME Section XI. By extending the multiple stream concept to the Class 1 tubesheet-to-shell and nozzle-to-shell welds, a good cross-section of the regenerative heat exhanger would be examined while a significant reduction in radiation exposure from this component would be achieved.

Following are some of the items that have been taken into consideration in the preparation of this request.

1. Radiation Levels Currently, the average dose rates at the regenerative heat exchanger are:

1.5 rem /hr general area (at 18")

4.0 rem /hr insulation surface (on contact) 7.0 rem /hr shell surface (on contact under the insulation)

2. Total Estimated Man-Rem Exposure Involved In the Examination Considering the tasks associated with conducting an examination on a particular examination area, the following time intervals have been required in the past:

t 0.2 man hours for insulation removal 0.1 man hours for weld cleaning and preparation 0.7 man hours for conducting the examination 0.2 man hours for insulation replacement Using the preceding dose rates and times, the following whole body and extremity exposures can be calculated per examination:

l

Reason for Limitation Page 2 Whole Body (using general area dose rates) :

1.5 rem /hr for insulation removal of 0.2 man hours = 0.3 man-rem 1.5 rem /hr for weld cleaning and preparation of 0.1 man hours = 0.15 man-rem 1.5 rem /hr for the examination of 0.7 man hours = 1.05 man -rem 1.5 rem /hr for insulation replacement of 0.2 man hours = 0.3 man-rem Total Whole Body Dose Per RHE Exam = 1.8 man-rem Extremities (hands, using contact dose rates):

4.0 rem /hr for insulation removal of 0.2 man hours = 0.8 man-rem 7.0 rem /hr for weld cleaning and preparation of 0.1 man hours = 0.7 man-rem 7.0 rem /hr for the examination of 0.7 man hours = 4.9 man-rem 4.0 rem /hr for insulation replacement of 0.2 man hours = 0.8 man-rem Total Extremities Dose Per RHE Exam = 7.2 man-rem The exposure savings per inspection interval, by a reduction of six examinations, would be 10.8 man-rem whole body and 43.2 man-rem extremities.

3. Shielding When exposure is utilized to place lead blankets and shields over non-examination areas of the RHE, the general area dose rates are reduced by approximately 50%, but the dose rates are still the highest encountered during an inservice inspection project. Also, the examiner who is conducting the examination does not have the benefit of the shielding.

4. Alternative Examinations Instead of examining all three Class 1 tubesheet-to-shell welds and all six class 1 nozzle-to-shell welds, we propose to examine tubesheet-to-shell weld RHE-2 and nozzle-to-shell welds RHE-N1 (inlet) and RHE-N4 (outlet). These welds are all located on the bottom heat exchanger (see Appendix l-A for an outline of the RHE and weld locations).

The bottom shell welds should be the ones to be inspected for two reasons. First of all, the bottom heat exchanger operates at the highest temperature of the three and is therefore the most highly stressed. Typical operating temperatures for letdown flow are 538aF into the bottom shell and 252*F out of the top shell. Secondly, the

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Reason for Limitation 4

Page 3 bottom shell welds can generally be more extensively inspected than the other shell welds. This can be seen by looking at the tables contained in Appendix l-B, which show the examination methods performed in the past and the coverage obtainable for each of the welds.

Not only does the information in Appendix l-B show the best welds to examine, it also shows that the coverage of some of the welds for which we are requesting relief is substantially limited. For example, using the terminology in the Appendix, only 25% of weld RHE-N9 can be examined by OL, 45, and 60 techniques. The fact that these limitations exist for some of the RHE welds is another point in favor of granting the relief request.

. 5. Previous Inspection Results Simply stated, all indications which were recorded during inspections

}' to this point were found to be either insignificant or geometric in nature. An insignificant indication is either a non-relevant

indication or an indication which is equal to or greater than the

examination recording level but less than the evaluation level.

l 6. Consequences of Weld Failure The consequences of a failure of one of the RHE welds have essentially been addressed in the plant's Final Safety Analysis i Report (FSAR). In the FSAR, to evaluate chemical and volume control

, system (CVCS) safety, failures or malfunctions were assumed I

concurrent with a loss of coolant accident (LOCA) and the consequences analyzed. A LOCA and a concurrent RHE weld failure is j included in the more general catagory of a rupture in the CVCS line

inside containment. During such an occurrence, the remote-operated valve located near the main coolant loop, upstream of the RHE, is closed on low pressurizer level to prevent supplementary loss of coolant through the letdown line rupture. The RHE would also

, eventually be isolated, with leakage being confined to containment, i

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in the case of a weld failure without a LOCA.

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1 CVC 2 LC-1001 REGENERATIVE HEAT EXCHANGER FIGURE A-7 A-7

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PoS T OFFICE OR AWER 28S10

• 6220 CULESR A RO AD . S AN ANTONIO. TEM AS US A 78284. e512t 684 SII1.f ELEx 76 7357 /, l' ~l OUAUTV ASSURAhCISYSTEMS TELD M7208 NUC ENGR $NT A A8s0 ENGisettniseo orvits0N TELD 7675M NUC FNGR ENT TELECOF'tR M January 9,1985 Doc. No. 17-7472(22)

Mr. Steve Pullins Wisconsin Electric Power Company

{ //. /4 . A * / f e Point Beach Nuclear Plant h/* [8. f/

6610 Nuclear Road Two Rivers, Wisconsin 54241 Subjact: Summary cf the Regenerative Heae Exchanger (REE)

Examinations Units 1 and 2 Performed at Point Beach Nuclear Plant.

Dear Mr. Pullins:

Enclosed is a summary of the RHE examinations performed to date at Point Beach Nuclear Plant, Units 1 and 2. This information is provided to assist you in the preparation of a relief request to be submitted to the U.S. Nuclear Regulatory Commission. This package consists of two tables, one each for Units 1 and 2. Each table consists of the following: veld number, category, limitation, resson for limitation,Section II examination methoi required, examination method performed and Section II coverage. An explanaticn of the table hesdings and terminology used precedes the tables.

If any additional information is needed, or if we can be of any further assistance, please contact us.

Sincerely,

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Rodn y M. Weber Project Manager Inspection Engineering Section Department of Engineering Services CE/kp t

I Enclosures s.

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TABLE HEADINGS WELD NUMBER - THE NUMBER DESIGNATED TO EACH SPECIFIC WELD BY WISCONSIN ELECTRIC POWER COMPANY CATEGORY - EACH WELD FALLS INTO A SPECIFIC CATEGORY, AS PER ASME 1977/S79 SECTION II CODE LIMITATION - WHEN FULL COVERAGE CANNOT BE ACHIEVED DURING THE EXAM-INATION OF A WELD-REASON FOR LIMITATION - THE SPECIFIC REASON WHY FULL COVERAGE CANNOT BE ACHIEVED.

EXAMPLES: 1) RESTRAINT - WHEN A RESTRAINT IS LOCATED WITHIN OR ADJACENT TO THE EXAM AREA, THEREFORE RESTRICTING FULL COVERAGE

2) SUPPORT - WHEN A SUPPORT IS LOCATED WITHIN OR ADJACENT TO THE EXAM AREA, THEREFORE RESTRICTING FULL COVERAGE

3) WELD CONFIGURATION - WHEN THE DESIGN OR "AS WELDED CONDITION" 0F THE WELD IN QUESTION PREVENTS FULL COVERAGE 4)N0ZZLE CONFIGURATION - WHEN THE N0ZZLE DESIGN PREVENTS FULL COVERAGE OF IHE EXAM AREA

5) TUBE SHEET CONFIGURATION - WHEN THE TUBE SHEET DESIGN PREVENTS EXAMINATION FROM ONE SIDE OF THE WELD

6) CAP CONFIGURATION - WHEN A CAP DESIGN OR CAP CURVATURE PREVENTS FULL COVERAGE

7) CURVATURE - WHEN THE RADIUS OF A COMPONENT IS SUCH THAT CURVATURE DOES NOT ALLOW PROPER EXAMINATION SECTION II EXAMINATION METHOD - THE SPECIFIC TYPE OF EXAMINATION RM UIRED BY 1977/S79 SECTION XI CODE EXAMINATION PERFORMED - THE TYPE OF EXAMINATION PERFORMED ON THE WELD SECTION II COVERAGE - THESE NUMBERS ARE CALCULATED AS A PERCENTAGE (EXAMINATION AREA COVERED DIVIDED BY EXAMINATION AREA RM UIRED). THE EXAMINATION AREA RMUIRED IS DETERMINED BY THE SECTION XI CODE RM UIREMENTS. THE EXAMINATION AREA I

COVERED IS DETERMINED BY QUANTITY AND TYPE OF LIMITATIONS EXAMPLES: 1)IF A LIMITATION PREVENTED EXAMINATION OF ONE SIDE OF THE WELD AREA, EITHER UPSTREAM OR DOWN-STREAM, THEN THE SECTION XI COVERAGE FOR THAT EXAMINATION IS 50%.

2)IF A LIMITATION PREVENTED THE EXAMINATION OF 4.5 INCHES OF WELD LENGTH ON A WELD 18.5 INCHES LONG, THEN THE SECTION XI COVERAGE IS 75% (14 DIVIDED BY 18.5 = .757) .

l IT SHOULD BE NOTED THAT, WHEN CALCULATING 63%, 64%, 66%, 69%, 74%, 75%,

AND 80%, EXACT NUMBERS WERE AVAILABLE FOR CALCULATION (i.e. EXAMPLE 2 ABOVE). HOWEVER, 25% AND 50% ARE APPROXIMATIONS WHICH WERE MADE USING THE DATA AVAILABLE (i.e. EXAMPLE 1 ABOVE).

IT SHOULD ALSO BE NOTED THAT THERE ARE DIFFERENCES IN COVERAGE AND LIMITATIONS BETWEEN UNITS 1 AND 2. THIS IS DUE PRIMARILY TO THE "AS

BUILT CONDITION" 0F THE WELDS IN QUESTION.

TERMIN0LOGT FULL COVERACE - WHEN 100% OF THE RMUIRED COVERAGE AREA IS EXAMINED FROM BOTH SIDES OF THE WELD DENOTES VISUAL EXAMINATIONS WHICH WERE PERFORMED AS PER RM UIREMENTS OF THE TECHNICAL SPECIFICATIONS

($) -

DENOTES THAT THE WELD WAS EXAMINED ONCE DURING THE FIRST INTERVAL AND ONCE DURING THE SECOND INTERVAL (f)

DENOTES THAT THE WELD WAS EXAMINED TWICE DURING THE FIRST INTERVAL

(+) -

DENOTES THAT THE WELD WAS EXAMINED ONLT DURING THE SECOND INTERVAL UT -

MANUAL ULTRASONIC EIAMINATION VT -

VISUAL EIAMINATION PT -

LIQUID PENETRANT EIAMINATION UP -

DENOTES THE UPSTREAM SIDE OF THE WELD D -

DENOTES THE DOWNSTREAM SIDE OF THE WELD OL -

0 DEGREE LAMINATION SCAN ON THE BASE METAL OW -

0 DEGREE WELD SCAN ON THE WELD METAL 45 -

45 DEGREE SHEAR WAVE SCAN PERPENDICULAR TO THE WELD FROM THE BASE METAL SIDE (S) 0F THE WELD 45T -

45 DEGREE SHEAR WAVE SCAN PARALLEL TO THE WELD FROM THE BASE METAL SIDE (S) 0F THE UELD AND ON THE WELD i

60 -

60 DEGREE SHEAR WAVE SCAN PERPENDICULAR TO THE WELD FROM THE t

BASE METAL SIDE (S) 0F THE WELD

POINT BEACH UNIT 1 NOTE: ALL INDICATIONS WHICH WERE RECORDED ON RHE WERE IVUND TO BE EITHER INSIGNIFICANT OR GEOMETRIC IN NATURE.

SEC.XI WELD REASON FOR NUMBER EXAM EXAM SEC. II CATGY LIMITATION LIMITATION METHOD PERFORMED COVERAGE RHE-1 B-B NO OL UP SUPPORT UT *VT - UT 100% OW, No 45,60 D CURVATURE 45T 50% OL, 45, o0 RHE-2($) B-B NONE UT *VT - UT 100%

RHE-3 B-B NONE UT *VT - UT 100%

REE-4 B-B NO 45,60 UP CURVATURE UT *VT - UT 100% OF, OL, 45T 50% 45, j

60 4

RHE-5 B-B No 45,60 UP CURVATURE UT *VT - UT 100% OW, OL, 45T 50% 45, '

60 RHE-6 B-B NONE UT *VT - UT 100%

RHE-7 B-B NONE UT *VT - UT 100%

RHE-8 B-B NONE UT *VT - UT

' 100%

RHE-9($) B-B No 45,60 UP CURVATURE UT *VT - UT 100% OW, OL, 45T 50% 45, 60 RHE-10 B-B NONE UT *VT - UT 100%

REE-11 B-B NONE UT *VT - UT 100%

i RHE-12 B-B NONE UT *VT - UT 100%

l RHE-N1 B-D NO OW,45T, WELD.CONFIG. UT UT 100% OL i

60 80% 45 LIMITED 45 SUPPORT RHE-N2(f) B-D NO 45T, 60 WELD CONFIG. UT UT 100% OL, No 45 D N0Z. CONFIG. 0W 50% 45 REE-N3 5-D NO 45T, 60 WELD CONFIG. UT UT 100% OL, No 45 UP N0Z. CONFIG. OW 50% 45 RHE-N4 B-D NO 45T, 60 WELD CONFIG. UT UT 100% OL, No 45 D N0Z. CONFIG. 0W 50% 45 RHE-N5 B-D NO OW,45T WELD CONFIG. UT UT 25% OL, LIMITED OL, SUPPORT 45,60 45, 60 l RHE-N6 B-D NO 45T,60 WELD CONFIG. UT UT 100% OW l NO OL,45 D N0Z. CONFIG. 50% OL, 45 RHE-N7 B-D No 0L,45 UP N0Z. CONFIG. UT UT 100% OW NO 45T, 60 WELD CONFIG. 50% OL, 45 RHE-N8 B-D NO 0L,45 D N0Z. CONFIG. UT UT 100% OW

( NO 45T, 60 WELD CONFIG. 50% OL, 45 I

. RHE-N9($) B-D No CW,45T WELD CONFIG. UT UT 25% OL, LIMITED OL, SUPPORT 45,60 45,60 REE-N10 B-D NO OL,45 D N0Z . CONFIG . UT UT 100% OW NO 45T, 60 WELD CONFIG. 50% OL, 45 RHE-Nil B-D NO OL,45 D N0Z. CONFIG. UT UT 100% OW NO 45T, 60 WELD CONFIG. 50% OL, 45 REE-N12(f) B-D NO 45T, 60 WELD CONFIG. UT UT 63% OL, LIMITED OL, SUPPORT OW,45 OW, 45 SUPPORT ($ ) 1-H NONE UT VT 0%

SUPPORT ($ ) B-H NONE UT VT 0%

SUPPORT ($) B-H NONE UT VT 0%

REE-Nil (+) C-B NO OL,45, N0Z. CONTIG. SURFACE UT-PT 100% OW, 45T N0Z. SIDE AND UT PT 50% 45, 45T SUPPORT 1(+) F-A NONE VT-3 VT-3 100:

SUPPORT 5(+) F-B NONE VT-3 VT-3 100%

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POINT BEACH UNIT 2 NOTE: ALL INDICATIONS WHICH WERE RECORDED ON RHE WERE MUND TO BE EITHER INSIGNIFICANT OR GEOMETRIC IN NATURE.

• ****** :. :. :. :. ; ; :. ; ; :. :. :. ; :. :. :. ;. ***************** **** *** * *********** s* ** *** * ** **

SEC.II WELD REASON MR EXAM EXAM SEC. XI NUMBER CATGT LIMITATION LIMITATION METHOD PERFORMED COVERAGE RHE-1 B-B NO OL,0W,45, SUPPORT UT *VT 0%

45T,6 0 RHE-2 B-B LIMITED OL, TUBE SHEET UT *VT - UT 50% OL, 45,45T,60 CONFIG. 0W,45, LIMITED OW SUPPORT 45T,60 RHE-3 B-B NONE UT *VT - UT 100%

RHE-4 B-B NONE UT *VT - UT 100%

RHE-5 B-B NO OL,45, CAP. CONFIG. UT *VT - UT 100% OW 45T,60 UP 50% OL, 45,45T,60 RHE-6 B-B LIMITED OL, N0Z. CONFIG. UT *VT - UT 100% OW 45,45T,60 UP 75% OL NO 45,45T, RESTIAINT 25% 45, 60 D 45T,60 RHE-7 B-B NO 0L,45, RESTRAINT UT *VT - UT 100% OW 45T,60 UP 50% OL, 45,45T,60 RHE-8 B-B NO 0L,45, CAP. CONFIG. UT *VT - UT 100% OW 45T,60 50% OL, 45,45T,60 RHE-9 B-B NONE UT UT 100%

RHE-10 B-B LIMITED OL, SUPPORT UT UT 45% OL, 45,60 45,60 NO OW,45T SUPPORT RHE-11 B-B LIMITED OL, SUPPORT UT UT 100% OW 45,45T,60 75% OL, 45,45T,60 RHE-12 B-B NONE UT UT 100%

RHE-N1($) B-D LIMITED OL SUPPORT UT UT 100% OW, NO 45T UP N0Z. CONFIG. 45 NO 60 WELD CONFIG. 66% OL 50% 45T RHE-N2 B-D LIMITED OL SUPPORT UT UT 100% OW, No 45T UP N0Z. CONFIG. 45 NO 60 WELD Q)NFIG. 66% OL 50% 45T RHE-N3 B-D No 45T UP N02. CONFIG. UT UT 100% OL, NO 60 WELD CONFIG. 0W 50% 45T RHE-N4($) B-D NO 45T UP N0Z. CONFIG. UT UT 100% OL, NO 60 WELD CONFIG. 0W 50% 45T RHE-N5 B-D LIMITED OL, RESTRAINT UT UT 75% OL, 45 45 NO OW,45T WELD CONFIG.

RHE-N6 B-D LIMITED OL, RESTRAINT UT UT 75% OL,

45 45 NO OW,45T WELD CONFIG.

, RHE-N7 B-D LIMITED OL RESTRAINT UT UT 64% OL NO OW,45T RESTRAINT 50% 45 NO 45 UP WELD CONFIG.

RHE-N8 B-D LIMITED OL RESTRAINT UT UT 69% OL NO OW,45T RESTRAINT 100% 45 RHE-N9 B-D LIMITED OL, SUPPORT UT UT 74% OL, 0W,45,45T OW,45,45T RHE-NIO B-D NONE UT OT 100%

REE-Nil B-D NONE UT UT 100%

REE-N12 B-D LIMITED OL, SUPPORT UT UT 100% OW 45,45T 75% OL, 45,45T SUPPORT B-H NONE UT VT 0%

SUPPORT B-H NONE UT VT 0%

SUPPORT B-H NONE UT VT 0%

SUPPORT 3(+)B-H NONE UT VT-3 0%

REE-N11(+) C-B LIMITED OL, N0Z. CONFIG. SURFACE UT-PT 100% OW, 45,45T AND UT PT 50% 45, 45T

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ATTACHMENT 2 UNIT 2 RELIEF REQUEST Relief Request No. Description RR-2-12 Regenerative Heat Exchanger Class 1 Shell and Nozzle Welds 4

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RR-2-12 Component Regenerative Heat Exchanger Exam Area Class 1 Tubesheet to Shell Welds Class 1 Nozzle to Shell Welds Isometric or Component Drawing Fig. A-7 ASME Section XI Category l B-B B-D ASME Section XI Item Number B2.60 B3.150 ASME Section XI Examination Requirement A volumetric examination of 100% of all tubesheet welds and nozzle welds during the second 10-year interval.

Alternative Examination A volumetric examination of accessible portions of all tubesheet welds and nozzle welds equivalent to one of the three identical sections of the regenerative heat exchanger during the second 10 year interval.

Reason for Limitation The regenerative heat exchanger (RHE) provides the major single source of radiation exposure accumulated during a nominal refueling outage inservice inspection project. The " regenerative heat exchanger" is actually three shell-and-tube heat exchangers connected in series. The RHE is designed to recover heat from the reactor coolant system letdown stream by reheating the charging stream during normal operation. The letdown stream flows through the shell of the RHE and the charging stream flows through the tubes.

To ensure adequate coverage of the component welds with a minimum of exposure, the multiple stream concept should be carried out in all the examination catagories. Currently only one of three Class 1 cap-to-shell welds, Class 2 cap-to-shell welds, Class 2 tubesheet-to-shell welds, and two of six Class 2 nozzle-to-shell welds are examined in accordance with allowances in IWB-2500 and IWC-2500 of ASME Section XI. By extending the multiple stream concept to the Class 1 tubesheet-to-shell and nozzle-to-shell welds, a good cross-section of the regenerative heat exhanger would be examined while a significant reduction in radiation exposure from this component would be achieved.

Following are some of the items that have been taken into consideration in the preparation of this request.

1. Radiation Levels Currently, the average dose rates at the regenerative heat exchanger are:

1.5 rem /hr general area (at 18")

4.0 rem /hr insulation surface (on contact) 7.0 rem /hr shell surface .(on contact under the insulation)

2. Total Estimated Man-Rem Exposure Involved In the Examination Considering the tasks associated with conducting an examination on a j particular examination area, the following time intervals have been 4 required in the past:

0.2 man hours for insulation removal i 0.1 man hours for weld cleaning and preparation 0.7 man hours for conducting the examination 0.2 man hours for insulation replacement Using the preceding dose rates and times, the following whole body and extremity exposures can be calculated per examination:

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Reason for Limitation Page 2 Whole Body (using general area dose rates):

a 1.5 rem /hr for insulation removal of 0.2 man hours = 0.3 man-rem 1.5 rem /hr for weld cleaning and preparation of 0.1 i

man hours = 0.15 man-rem 1.5 rem /hr for the examination of 0.7 man hours = 1.05 man-rem 1.5 rem /hr for insulation replacement of 0.2 man hours = 0.3 man-rem Total Whole Body Dose Per RHE Exam = 1.8 man-rem I Extremities (hands, using contact dose rates) :

E 4.0 rem /hr for insulation removal of 0.2 man hours = 0.8 man-rem 7.0 rem /hr for weld cleaning and preparation of 0.1 man hours = 0.7 man-rem 7.0 rem /hr for the examination of 0.7 man hours = 4.9 man-rem

. 4.0 rem /hr for insulation replacement of 0.2 man hours = 0.8 man-rem Total Extremities Dose Per RHE Exam = 7.2 man-rem The exposure savings per inspection interval, by a reduction of six examinations, would be 10.8 man-rem whole body and 43.2 man-rem l extremities.

J

3. Shielding When exposure is utilized to place lead blankets and shields over non-examination areas of the RHE, the general area dose rates are j reduced by.approximately 50%, but the dose rates are still the highest encountered during an inservice inspection project. Also, the examiner who is conducting the examination does not have the benefit of the shielding.

, 4. Alternative Examinations

, Instead of examining all three Class 1 tubesheet-to-shell welds and all six class 1 nozzle-to-shell welds, we propose to examine tubesheet-to-shell weld RHE-2 and nozzle-to-shell welds RHE-N1 (inlet) and RHE-N4 (outlet). These welds are all located on the bottom heat exchanger (see Appendix 2-A for an outline of the RHE and weld locations) .

The bottom shell welds should be the ones to be inspected for two reasons. First of all, the bottom heat exchanger operates at the highest temperature of the three and is therefore the most highly

,' stressed. Typical operating temperatures for letdown flow are 538aF into the bottom shell and 252*F out of the top shell. Secondly, the

. _ . _ _ _ _ _ .. . .. - . - - _ . - = -_.

4 i

Reason for Limitation '

Page 3 4

bottom shell welds can generally be more extensively inspected than the other shell welds. This can be seen by looking at the tables I

contained in Appendix 2-B, which show the examination methods performed in the past and the coverage obtainable for each of the 3

welds.

Not only does the information in Appendix 2-B show the best welds to j examine, it also shows that the coverage of some of the welds for ,

L

. which we are requesting relief is substantially limited. For t

example, using the terminology in the Appendix, weld RHE-NS can be examined only by OL and 45 techniques to an extent of 75%. The fact that these limitations exist for some of the RHE welds is another point in favor of granting the relief request.

5. Previous Inspection Results

' Simply stated, all indications which were recorded during inspections to this point were found to be either insignificant or geometric in nature. An insignficant indication is either a non-relevant indication or.an indication which is equal to or greater than the j examination recording level but less than the evaluation level.

! 6. Consequences of Weld Failure The consequences of a failure of one of the RHE welds have essentially been addressed in the plant's Final Safety Analysis j Report (FSAR). In the PSAR, to evaluate chemical and volume control

system (CVCS) safety, failures or malfunctions were assumed i

concurrent with a loss of coolant accident (LOCA) and the consequences analyzed. A LOCA and a concurrent RHE weld failure is i

included in the more general catagory of a rupture in the CVCS line inside containment. During such an occurrence, the remote-operated valve located near the main coolant loop, upstream of the RHE, is ~

closed on low pressurizer level to prevent supplementary loss of I

coolant through the letdown line rupture. The RHE would also eventually be isolated, with leakage being confined to containment, in the case of a weld failure without a LOCA.

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-S O U T H W E S T R E S E A R C H I N S TI T U T E 4/

POST OFFICE DR AWER 28510 6220 CULE8 R A ROAD . S AN AN TONIO, tex A S. US A 78284. tS12) 664-5111* TELEX 76 7357 QUAUTV ASSURANCE SYSTEMS TELEX 767209 NUC ENGR $47 A AND ENGINEER NG DiveSION TELEX 787579 NUC ENGR $NT TELECOPtER 804 January 9,1985 Doc. No.17-7472(22)

Mr. Steve Pullins { /). /C . 3 * / fI 6 Wisconsin Electric Power Company Point Beach Nuclear Plant [t/' ((. V 6610 Nuclear Road Two Rivers, Wisconsin 54241

Subject:

Summary cf the Regenerative Heat Exchanger (RHE)

Examinations Performed at Point Beach Nuclear Plant, Units 1 and 2

Dear Mr. Pullins:

Enclosed is a suunnary of the RHE examinations performed to date at Point Beach Nuclear Plant, Units I and 2. This information is provided to assist you in the preparation of a relief request to be submitted to the U.S. Nuclear Regulatory Commission. This package consists of two tables, one each for Units 1 and 2. Each table consists of the following: weld number, category, limitation, reason for limitation,Section II examination method required, examination method performed and Section II coverage. An explanation of the table headings and terininology used precedes the tables.

If any additional information is needed, or if we can be of any further assistance, please contact us.

Sincerely,

[ ,r --

Roda y M. Weber Project Manager Inspection Engineering Section Department of Engineering Services CE/kp Enclosures WQ T

s j $ $ =N c gc s p N -1 g u s r% .^r sas. amo w a s = e = o r o =. oc 1 I oy m* sus >!"

TABI.E HEADINGS WELD NUMBER - THE NUMBER DESIGNATED TO EACH SPECIFIC WELD BY WISCONSIN ELECTRIC POWER COMPANY CATEGORY - EACH WELD FALLS INTO A SPECIFIC CATEGORY, AS PER ASME 1977/S79 SECTION XI CODE LIMITATION - WHEN FULL COVERAGE CANNOT BE ACHIEVED DURING THE EXAM-INATION OF A WELD REASON FOR LIMITATION - THE SPECIFIC REASON WHY FULL COVERAGE CANNOT BE ACHIEVED.

EXAMPLES: 1) RESTRAINT - WHEN A RESTRAINT IS LOCATED WITHIN OR ADJACENT TO THE EXAM AREA, THEREFORE RESTRICTING FULL COVERAGE

2) SUPPORT - WHEN A SUPPORT IS LOCATED WITHIN OR ADJACENT TO THE EXAM AREA, THEREFORE RESTRICTING FULL COVERAGE

3) WELD CONFIGURATION - WHEN THE DESIGN OR "AS WELDED CONDITION" 0F THE WELD IN QUESTION PREVENTS FULL COVERAGE 4)N0ZZLE CONFIGURATION - WHEN THE N0ZZLE DESIGN PREVENTS FULL COVERAGE OF IHE EXAM ARIA

5) TUBE SHEET CONFIGURATION - WHEN THE TUBE SHEET DESIGN PREVENTS EXAMINATION FROM ONE SIDE OF THE WELD

6) CAP CONFIGURATION - WHEN A CAP DESIGN OR CAP CURVATURE PREVENTS FULL COVERAGE

7) CURVATURE - WHEN THE RADIUS OF A COMPONENT IS SUCH THAT CURVATURE DOES NOT ALLOW PROPER EXAMINATION SECTION XI EXAMINATION METHOD - THE SPECIFIC TYPE OF EXAMINATION RMUIRED BY 1977/S79 SECTION XI CODE EXAMINATION PERFORMED - THE TYPE OF EXAMINATION PERFORMED ON THE WELD SECTION XI COVERAGE - THESE NUMBERS ARE CALCULATED AS A PERCENTAGE (EXAMINATION AREA COVERED DIVIDED BY EXAMINATION AREA RMUIRED). THE EXAMINATION AREL EQUIRED IS DETERMINED BY THE SECTION XI CODE RM UIREMF%'$. THE EXAMINATION AREA COVERED IS DETERMINED BY (2$ TJV AND TYPE OF LIMITATIONS EXAMPLES: 1)IF A LIMITh'I'J 1H ' OITED EXAMINATION OF ONE SIDE OF THE %.LD al.e, EITHER UPSTREAM OR DOWN-STREAM, THEN THE SECTION XI COVERAGE FOR THAT EXAMINATION IS 50%.

2)IF A LIMITATION PREVENTED THE EXAMINATION OF 4.5 INCHES OF WELD LENGTH ON A WELD 18.5 INCHES LONG, THEN THE SECTION XI COVERAGE IS 75% (14 DIVIDED BY 18.5 = .757) .

IT SHOULD BE NOTED THAT, WHEN CALCULATING 63%, 64%, 66%, 69%, 74%, 75%,

AND 80%, EXACT NUMBERS WERE AVAILABLE FOR CALCULATION (i.e. EXAMPLE 2 ABOVE). HOWEVER, 25% AND 50% ARE APPROXIMATIONS WHICH WERE MADE USING THE DATA AVAILABLE (i.e. EXAMPLE 1 ABOVE).

IT SHOULD ALSO BE NOTED THAT THERE ARE DIFFERENCES IN COVERAGE AND LIMITATIONS BETWEEN UNITS 1 AND 2. THIS IS DUE PRIMARILY TO IEE "AS

BUILT CONDITION" 0F THE WELDS IN. QUESTION.

TERMINOLOGY FULL COVERAGE - WHEN 100% OF THE REQUIRED COVERAGE AREA IS EXAMINED FROM BOTH SIDES OF THE WELD DENOTES VISUAL EXAMINATIONS WHICH WERE PERFORMED AS PER R R UIREMENTS OF THE TECHNICAL SPECIFICATIONS

($) -

DENOTES THAT THE WELD WAS EXAMINED ONCE DURING THE FIRST INTERVAL AND ONCE DURING THE SECOND INTERVAL (f) DENOTES THAT THE WELD WAS EXAMINED TWICE DURING THE FIRS'l INTERVAL

(+) -

DENOTES THAT THE WELD WAS EXAMINED ONLY DURING THE SECOND INTERVAL UT -

MANUAL ULTRASONIC EXAMINATION VT -

VISUAL EXAMINATION PT -

LIQUID PENETRANT EXAMINATION UP -

DENOTES THE UPSTREAM SIDE OF THE WELD D -

DENOTES THE DOWNSTREAM SIDE OF THE WELD OL -

0 DEGREE LAMINATION SCAN ON THE BASE METAL OW -

0 DEGREE WELD SCAN ON THE WELD METAL 45 -

45 DEGREE SHEAR WAVE SCAN PERPENDICULAR TO THE WELD FROM THE BASE METAL SIDE (S) 0F THE WELD 45T -

45 DEGREE SHEAR WAVE SCAN PARALLEL TO THE WELD FROM THE BASE METAL SIDE (S) 0F THE WELD AND ON THE WELD 60 -

60 DEGREE SHEAR WAVE SCAN PERPENDICULAR TO THE WELD FROM THE BASE METAL SIDE (S) 0F THE WELD

~

,, POINT BEACH UNIT 1 NOTE: ALL INDICATIONS WHICH WERE RECORDED ON RHE WERE MUND TO BE EITHER INSIGNIFICANT OR GEOMETRIC IN NATURE.

SEC.XI WELD REASON FOR EXAM EXAM SEC. XI

, NUMBER CATGY LIMITATION LIMITATION METHOD PERFORMED COVERAGE RHE-1 B-B NO OL UP SUPPORT UT *VT - UT 100% OW, No 45,60 D CURVATURE 45T 50% OL, 45, 60 RHE-2($) B-B NONE UT *VT - UT 100%

RHE-3 B-B NONE UT *VT - UT 100%

RHE-4 B-B NO 45,60 UP CURVATURE UT *VT - UT 100% OW, OL, 45T 50% 45, 60 RHE-5 B-B NO 45,60 UP CURVATURE UT *VT - UT 100% OW, OL, 45T 50% 45, 60 REE-6 E-B NONE UT *VT - UT 100%

RHE-7 B-B NONE UT *VT - UT 100%

RHE-8 B-B NONE UT *VT - UT 100%

RHE-9($) B-B No 45,60 UP CURVATURE UT *VT - UT 100% OW, OL, 45T 50% 45, 60 REE-10 B-B NONE UT *VT - UT 100%

RHE-11 B-B NONE UT *VT - UT 100%

RHE-12 B-B NONE UT *VT - UT 100%

RHE-N1 B-D NO OW,45T, WELD.CONFIG. UT UT 100% OL 60 80% 45 LIMITED 45 SUPPORT RHE-N2(f) B-D No 45T, 60 WELQ CONFIG. UT UT 100% OL, NO 45 D N0Z. CONFIG. OW 50% 45 RHE-N3 B-D No 45T, 60 WELD CONFIG. UT UT 100% OL, NO 45 UP N0Z. CONFIG. 0W 50% 45 RHE-N4 B-D No 45T, 60 WELD CONFIG. UT UT 100% OL, No 45 D N0Z. CONFIG. 0W 50% 45 RHE-N5 B-D NO OW,45T WELD CONFIG. UT UT 25% OL, LIMITED OL, SUPPORT 45,60 45, 60 RHE-N6 B-D NO 45T,60 WELD CONFIG. UT UT 100% OW NO OL,45 D N0Z. CONFIG. 50% OL, 45 RHE-N7 B-D No OL,45 UP N0Z. CONFIG. UT UT 100% OW

No 45T, 60 WELD CONFIG. 50% OL, 45 RHE-N8 B-D NO OL,45 D N0Z. CONFIG. UT UT 100% OW NO 45T, 60 WELD CONFIG. 50% OL, 45 e

..- RHE-N9($) B-D NO OW,45T WELD CONFIG. UT UT 25% OL,

.. LIMITED OL, SUPPORT 45,60 45,60 RHE-N10 B-D NO OL,45 D N0Z. CONFIG. UT UT 100% OW No 45T, 60 WELD CONFIG. 50% OL, 45 RHE-Nil B-D NO OL,45 D N0Z. CONFIG. UT UT 100% OW No 45T, 60 WELD CONFIG. 50% OL, 45 RHE-N12(f) B-D No 45T, 60 WELD CONFIG. UT UT 63% OL, LIMITED OL, SUPPORT OW,45 OW, 45 SUPPORT ($) B-H NONE UT VT 0%

SUPPORT ($) B-H NONE UT VT 0%

SUPPORT ($) B-H NONE UT VT 0%

RHE-Nil (+) C-B NO OL,45, N0Z. CONFIG. SURFACE UT-PT 100% OW, 45T N0Z. SIDE AND UT PT 50% 45, 45T SUPPORT 1(+) F-A NONE VT-3 VT-3 100%

SUPPORT 5(+) F-B NONE VT-3 VT-3 100%

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POINT BEACH UNIT 2 NOTE: ALL INDICATIONS WHICH WERE RECORDED ON RHE WERE EUND TO BE EITHER INSIGNIFICANT OR GEONETRIC IN NATURE.

SEC.XI WELD REASON M R EXAM EXAM SEC. XI NUMBER CATGY LIMITATION LIMITATION METHOD PERFORMED COVERAGE RHE-1 B-B NO OL,0W,45, SUPPORT UT *VT 0%

45T,60 RHE-2 B-B LIMITED OL, TUBE SHEET UT *VT - UT 50% OL, 45,45T,60 CONFIG. 0W,45, LIMITED OW SUPPORT 45T ,6 0 RHE-3 B-B NONE UT *VT - UT 100%

RHE-4 B-B NONE UT *VT - UT 100%

RHE-5 B-B NO OL,45, CAP. CONFIG. UT *VT - UT 100% OW 45T,60 UP 50% OL, 45,45T,60 RHE-6 B-B LIMITED OL, N0Z. (X)NFIG. UT *VT - UT 100% OW 45,45T,60 UP 75% OL NO 45,45T, RESTRAINT 25% 45, 60 D 45T,60 RHE-7 B-B NO OL,45, RESTRAINT UT *VT - UT 100% OW 45T,60 UP 50% OL, 45,45T,60 RHE-8 B-B NO OL,45, CAP. CONFIG. UT *VT - UT 100% OW 45T,60 50% OL, 45,45T,6 0 RHE-9 B-B NONE UT UT 100%

RHE-10 B-B LIMITED OL, SUPPORT UT UT 45% OL, 45,60 45,60 NO OW,45T SUPPORT RHE-Il B-B LIMITED OL, SUPPORT UT UT 100% OW

! 45,45T ,6 0 75% OL,

( 45,45T,60 i RHE-12 B-B NONE UT UT 100%

RHE-N1(S) B-D LIMITED OL SUPPORT UT UT 100% OW, NO 45T UP N0Z. CONFIG. 45 NO 60 WELD CONFIG. 66% OL 50% 45T RHE-N2 B-D LIMITED OL SUPPORT UT UT 100% OW, NO 45T UP N0Z. CONFIG. 45 NO 60 WELD CONFIG. 66% OL 50% 45T RHE-N3 B-D NO 45T UP N0Z. CONFIG. UT UT 100% OL, NO 60 WELD (X)NFIG. OW t 50% 45T l

RHE-N4($) B-D No 45T UP N0Z. CONFIG. UT UT 100% OL, l

NO 60 WELD CONFIG. 0W 50% 45T RHE-N5 B-D LIMITED OL, RESTRAINT UT UT 75% OL, 45 45 NO OW,45T WELD CONFIG.

RHE-N6 B-D LIMITED OL, RESTRAINT UT UT 75% OL,

45 -

45

.. NO OW,45T WELD CONFIG.

RHE-N7 B-D LIMITED OL RESTRAINT UT UT 64% OL NO OW,45T RESTRAINT 50% 45 NO 45 UP WELD CONFIG.

RHE-N8 B-D LIMITED OL RESTRAINT UT UT 69% OL NO OW,45T RESTRAINT 100% 45 RHE-N9 B-D LIMITED OL, SUPPORT UT UT 74% OL, OW,45,45T OW,45,45T RHE-NIO B-D NONE UT UT 100%

RHE-Nil B-D NONE UT UT 100%

RHE-N12 B-D LIMITED OL, SUPPORT UT UT 100% OW 45,45T 75% OL, 45,45T SUPPORT B-H NONE UT VT 0%

SUPPORT B-H NONE UT VT 0%

SUPPORT B-H NONE UT VT 0%

SUPPORT 3(+)B-H NONE UT VT-3 0%

RHE-Nil (+) C-B LIMITED OL, N0Z. CONFIG. SURFACE UT-PT 100% OW, 45,45T AND UT PT 50% 45, 45T 1

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