ML20138H558

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Summary of 961126 Meeting W/Util in Rockville,Md to Discuss Two Major Issues Related to SG Tube Integrity at Facility. W/List of Attendees & Viewgraphs
ML20138H558
Person / Time
Site: Three Mile Island Constellation icon.png
Issue date: 12/19/1996
From: Norris J
NRC (Affiliation Not Assigned)
To:
NRC (Affiliation Not Assigned)
References
TAC-M97311, NUDOCS 9701060114
Download: ML20138H558 (60)
v • d • e


Text

._ .. ...

V UNITED STATES 9m/890 g

g j NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 30e06-4001 i

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\,,g +/- December 19, 1996 LICENSEE: GPU Nuclear Corporation i-i FACILITY: Three Mile Island, Unit 1 (TMI-1) l l

SUBJECT:

SUMARY OF NOVEMBER 26, 1996 MEETING REGARDING STEAM GENERATOR ISSUES AT TMI-I (TAC NO. M97311)

On Tuesday, September 24, 1996, a meeting was held at NRC headquarters, One White Flint North, Rockville, Maryland, between GPU Nuclear Corporation (GPU/ licensee) and the NRC staff. The meeting was at the staff's request to discuss with the licensee two major issues related to steam generator tube integrity: (1) the use of a signal-to-noise and voltage screening criteria for dispositioning steam generator tube eddy current indications; and (2) how structural and leakage integrity of the reactor coolant pressure boundary (RCPB) is ensured, particularly with respect to the portion of the steam generator tubes in the upper tubesheet of the steam generator.

With respect to the screening criteria, the staff is concerned that such criteria do not ensure that tubes in excess of the tube repair criteria (i.e., l 40% through-wall) will be removed from service. With respect to the structural and leakage integrity of the steam generator tubes, the staff is concerned that the integrity of this portion of the RCPB.is not being assessed since the portion of the steam generator tubes located within the tubesheet are not required to be inspected by TMI's technical specifications.

The licensee presented material related to the historical background of the .

steam generators, the techniques used to inspect the steam generators, the i structural integrity of the tubes in the upper tubesheet region, and the scopes of the pst and future inspections for the two steam generators. The meeting atteWe are Msted in Enclosure 1. A copy of the material presented by the licen we is included as Enclosure 2.  !

Based on the presentation, the staff indicated at the end of the meeting that the criteria used for dispositioning eddy current indications, specifically the below voltage criteria (BVC), did not represent an immediate safety concern but rather a compliance issue since the BVC does not appear to demonstrate compliance with the Technical Specification tube repair limits.

The staff also indicated that there appeared to be two options to resolve this issue: (1) demonstrate that the screening criteria satisfies the repair criteria in the technical specifications; or (2) amend the technical  ;

s wcifications to permit the use of ruch criteria. The staff also indicated tiat with respect to the inspection scope within the tubesheet that the concern is primarily a leakage integrity issue. The concern is based on the lack of inspections performed below the roll transition in the lower tubesheet and in the 6-inch qualification zone above the kinetic expansion. Inspections in the tubesheet region are required of all other Babcock and Wilcox t once-through steam generators. The staff commented that there appear to also t DWn 0000es NRC FILE CENTER CO 9701060114 961219 PDR ADOCK 05000289 P PDR ,

l' Mr. James Knubel ,

be two approaches to resolve this issue: (1) inspect sufficient length in the tubesheet to ensure leakage integrity (this is the preferred approach); and (2) bound the problem by assuming the worse case degradation and then demonstrating that adequate leakage integrity exists (the feasibility of such an approach is questionable).

The licensee indicated that they do not believe the use of a signal-to-noise 4

and voltage screening criteria for dispositioning indications is a technical specification compliance issue since the staff had previously reviewed and approved portions of their tube integrity program. The staff indicated that it would need to look into this matter and encouraged the licensee to do so also.

/ 1 W.

J n A'. Norris, enior Project Manager i P ject Directorate I-3 Di ision of Reactor Projects - I/II Office of Nuclear Reactor Regulation

! Docket No. 50-289

Enclosures:

As stated i

cc w/ enclosures: Licensee and service list i

/

4 1 i 4

T C

0 e

j' iy Mr. James Knubel l be two approaches to resolve this issue: .(1) inspect sufficient length in the tubesheet to ensure leakage integrity (this is the preferred approach); and (2) bound the problem by assuming the worse case degradation and then .

demonstrating that adequate leakage integrity exists (the feasibility of such I an approach is questionable).

The licensee indicated that they do not believe the use of a signal-to-noise and voltage screening criteria for dispositioning indications is a technical specification compliance issue since the staff had previously reviewed and approved portions of their tube integrity program. The staff indicated that-it would need to look into this matter and encouraged the licensee to do so also.

(Original Signed By)

Jan A. Norris, Senior Project Manager Project Directorate I-3 Division of Reactor Projects - 1/II Office of Nuclear Reactor Regulation l Docket No. 50-289 l I

Enclosures:

As stated cc w/enclosuras: Licensee and service list i

Distribution  !

HARD COPY E-MAIL Docket File FMiraglia/AThadani LDudes ,

PUBLIC RZimmerman Alohmeier ,

PDI-3 Plant SVarga TSullivan  ;

OGC JZwolinski KKarwoski ACRS JStolz JStrosnider ,

JNorris PRush  !

EDunnington WDean EJordan i

DOCUMENT NA

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m \NORRIS\ME.ETSUM6.TMI.wmc.c.,,-

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OFFICE PW:PQT-W l9 LA:PDII-2 l6 D:PDI-2V ( T~

l l NAME Jhorr'isc4 EDunnington Pfh JStolz DATE 12/17/96 12//7/96 12/7/96 0FFICIAL RECORD COPY

t Three Mile Island Nuclear Station, Unit No. I cc:

Michael Ross Robert B. Borsua Director, O&M, TMI B&W Nuclear Technologies GPU Nuclear Corporation Suite 525 P.O. Box 480 1700 Rockville Pike Middletown, PA 17057 Rockville, MD 20852 John C. Fornicola William Dornsife, Acting Director Director, Planning and Bureau of Radiation Protection Regulatory Affairs Pennsylvania Department of

GPU Nuclear Corporation Environmental Resources 100 Interpace Parkway P.O. Box 2063
Parsippany, NJ 07054 Ha.rrisburg, PA 17120 Jack S. Wetmore Dr. Judith Johnsrud Manager, TMI Regulatory Afftirs National Energy Committee GPU Nuclear Corporation Sierra Club
P.O. Box 480 433 Orlando Avenue Middletown, PA 17057 State College, PA 16803 Ernest L. Blake, Jr., Esquire Mr. James Knubel, Vice President
Shaw, Pittman, Potts & Trowbridge and Director - TMI-I 2300 N Street, NW. GPU Nuclear Corporation Washington, DC 20037 P.O. Box 128 Forked River, NJ 08731 i Chairman Board of County Commissioners of Dauphin County Dauphin County Courthouse Harrisburg, PA 17120 Chairman Board of Supervisors

, of Londonderry Township R.D. #1, Geyers Church Road Middletown, PA 17057 Michele G. Evans Senior Resident Inspector (TMI-1)

U.S. Nuclear Regulatory Commission P.O. Box 311 Middletown, PA 17057 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 i

i MEETING BETWEEN TMI-1 AND l NRC STAFF REGARDING STEAM GENERATOR ISSUES i NOVEMBER 26,1996 3 LIST OF ATTENDEES I

Ramt Office 1

Jan Norris NRC/NRR Julien Abramovici GPUN

! S. D. Leshnoff GPUN

! Bob Knight GPUN R. O. Barley GPUN Patrick Walsh GPUN Rich Freeman GPUN i Gene Navratil GPUN l

Laura Dudes NRC/ Region I A. Lohmeier NRC/ Region I Bob Borsum FTI Ted Sullivan NRC/NRR/EMCB Ken Karwoski NRC/NRR/EMCB Jack Strosnider NRC/DE Phillip Rush NRR/EMCB Barry Sullivan NUS Info. Services l

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- TMI-1 OTSG Integrity - GPU Nuclear Inc.

Proposed Agenda 1

Introdu'ctions/ Meeting Purpose P. Walsh Background ,

R. Barley I

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! Eddy Current Techniques G. Navratil i

i StructuralIntegrity .

S. Leshnoff

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Past EgTInspection Results G. Navratil ECTInspection Plans for 12R .

Summary R. Barley /P. Walsh

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NRC Questions l

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- Voltage S.creening critena l

- - Previous NRC reviews (incl.1NUREG-1019) , .

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- Most recent eddy current insp. .

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Plans for next eddy: current.insp.

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!- - ~ How are indications >40% T.W. detected.and i

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reimoved from service?

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e .How.is intsgrity;of RCPB assured?

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TMI-1 OTSG Background

- 1981: TMI-l's Steam Generator tubes were l damaged by thiosulfate intrusion.

l - The plant had been shutdown.

- Sodium Thiosulfate Tank (now removed;,

j was the contaminant source.

4 l

- A low-temperature (i.e., shutdown) damage l mechanism - Mechanism now inactive l

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1.___.,__...,__. . _ _ _ _ _ _ . _ _ _ _ . _ _ _ _ _ . . _ _ _ _ . _ . . . _ _ _ . _ _ . _ _ _ _ . _ _ _ _ _ . . , _ . - . _

All of the inservice tubes (approx. 31,000) l were kinetically expanded.

Inspection and Repair Program presented to NRC in:

i Topical Report #8, Rev. 3 1

Public Hearings .

License Amendment Request which resulted in Amendment No.103 L

i i

i l

- GPb demonstrated the ability to reliably l ,

detect degradation in excess of 40% T.W.

i using bobbin probes and 8 x 1 probes.

[  :

- Methods were reviewed by NRC and .

I documented in XLREG-1019, "TMI-1 l

Steam Generator Repair Safety Evaluation

l. Report": .

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- NCREG-1019, "TMI-1 Steam Generator l Repair Safety Evaluation Report" stated on l Page 15: -

. .. . Based on the above evaluation, the staff concludes that the eddy-current techniques l

! developed and qualified for inspection of the l OTSG tubing demonstrated the ability to

j. reliably detect and size, with a high degree of

! certainty, the defects that were present in the l

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t TMI-1 T.S. Amendment No. 103 (1984) i permitted the operation of the plant with its repaired steam generators (with a more restricted allowable leakrate).

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I Damage mechanism is now inactive in the l TMI .1 OTSGs.

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l' ECT data' analysis of degraded tube population shows no growth rate since 1985.

No leaking tubes caused by IGSAC have

! been detected in leak tests since 1985.

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J TMI-1 Tube Pull Campaigns

- 32 Tubes Pulled in campaigns since 1981 i

- Most recent tube pull was during the 6R Outage (11/86-3/87) 4 i

- Laboratory ' analyses ofpulled tube sections confirmed repair methods and ECT capability i

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l Present OTSG Status j . _

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A" OTSG: 1269 of 15 531 tubes plugged. (8.2% plugged)

"B".OTSG 3.'78 of 15,531 tubes plugged- (2'.4%' plugged)

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- Primary-to-Sec~ondary Leakrate 0.0076 gph (from 11/25/96 data)

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. P/S leakage ~ in recent cycles has been due to tube plug-leakage, not l new T.W. tube defects.

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5 TLBES REPAIRED SINCE RESTART OUTAGE IDFLAWS DIS STUCK PUILED MIS- WEAR HCF ODIGA 'IUFAL PROBE PLUGGED SM 18 6 1 0 1 0 0 0 26 Mar'86

' 6R 31 2 2 3 1 0 0 0 39 Oct '86 7R 16 1 0 0 0 4 0 0 21 Jun '88 .

8R 4 2 0 0 0 2 0 0 8 Jan '90 8U1 0 , 1 0 0 0 0 1 0 2 Mar'90 -

9R 2 0 0 0 0 1 0 0 3 Sept'91 .

,10R 2 0 0 0 0 U~ 0 0 2 Sept'93 11R 3 0 0 0 0 2 0 1 6 Sept'95 6

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. Since! the restart of TMI-1 in 1985, one of

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l, our niain effort's has been to monitor the '

health of the OTSGs.

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This includes:. -

- Continuing to monitor OTSgis for damage initiated by the origindl thiosulfate intrusion and

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. ' Monitoring the OTSGs for other damage ~

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mechanisms. -

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Freespan Exam Techniques 1

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- Detection Witli 0.510 HF Bobbin l

l - Examine From LTS Roll Transition to Kinetic Expansion Transition

! - Confirmation With Pancake Probe (MRPC) l

- Pancake Disposition Determines Additional Action (e.g., Future Monitoring, Sizing With .540 Bobbin Coil Probe) l

- Voltage Normalization 10 Volts on Four 20% Holes

[Our 1.0 Volts Corresponds to the Industry Norm of 0.4 Volts]

! - No Pure Voltage Only Disposition i

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4 BVC Indication The Following Defines BVC Indications:

- ID Initiating AND

- Less Than 3 to 1-Signal to Noise Ratio AND

- Less Than 1 Volt AND

- Less Than 0.5" Circumferential Length e

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  • NDD" CONFIRMS

- INDICATION I I EVALUATE BOBBIN DATA FOR:

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AS, "NRl", .

S/N RATIO PERCENT T.W. BASED ON AshE STANDARD

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INDICATION INDICATION INDICATION - >= 40%

< 20% T.W. 20% TO 39%

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REPORT BOSS 4N COIL . REPORT BOSRIN Coll . REPORT BOBSIN Coll PHASE. VOLTAGE. PERCENT PHASE. VOLTAGE. PERCENT PHASE VOLTAGE. PERCENT REPORT MRPC REPORT MRPC REPORT MRPC LENGTH WIDTH, ORIENTATION LENGTH,WDTH ORIENTATION

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MONITOR. MONITOR DISPOSITION

.AS BASED AS "NRl" ON % T.W.

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KET Exam Techniques E a-w.

- Used 0.187" Coil ~ Diameter 8X1 -Probe During 10R

- Used 0.115" MR MRPC 3 Coil Probe During 11R .

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- MRPC Indic$tions Dispositioned With Same: Flow Charts 6,

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Bobbin Probe Capabilities j . . .

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Through WalliSizing;Has a 13.2% RMSE forindi' cations-

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>3:1 S/N or 51 Volt y . . -

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. Data Set Size and Accuracy Meets Appendix H l

Requir.ementsior Detection and Sizing .

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Detection Capability Acceptable Per NUREG-1019 l

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NUREG-1919 CHANGE: .

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  • MIZ-18 Used to Compare MIZ-12 Results

! . NUREG-10.19 ~

~ Fr~om Same .Ontage Used MIZ 12 With Amplifiers 4 . MIZ-30 TS Equivalent or Superior to MIZ-18

!- andiHigh Gain " '. ~ Trending Over 7. Outages Indicates l .

Equivalent Results for ISI Tube Population i

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DegradedTube Trending 4

TABLE M-9 l Comparison of Statistical Evaluation to Previous Evaluations Mean Sid Mean Std

. Period N' umber ,.

' Deviation Change Deviation Change Inds

% T.W.  %.T.W. ~ Volts .

Volts i

6.1

-0.2 0.3 SM 152' -2.6 -

6.6 +0.0 0.2 6R 118'

+1.1 ..

5.5 +0.2 0.3

+2.6' 7R 119' .

-0.2 7.43 -0.25 0.35 8R 291

-25 '6.96

+0.07 0.31 9R 229 .

6.62 +0.16 0.28

. 10R 207 - -0.6. ,

6.39- -0.26 0.40 11R 197 .

+0.9 . .

. Previous data extracted f'r om GPUN TDR I 134, Revision 0 (Reference 13) e np

--m- e -_--w- e.-

7- v e . **-ww-g gW+ e - == y--pw *.-e"- =wi v w' W

,1 . .

4 1

! Dete.ction Probe Size Changed From

~

I

. 540" To .510" Diameter i

i

~

~

- - 1982 Studies Indicated the .540 ' Probe With High Gain Provided the Best Results for ID Degradation 1

~

.GP.UN Used .540 Bobbin With High Gain (Accepted in

~

NUREG-1019) f .

- High Gain .Was Main Contributor to Improvement i ' '

l ~ .

- During 6R. Outage 54 Indications ~Were.Used for Insitu Comparison of Probes l

t

0 Probe Size (Continued) i l

- 51 of 54 Indications Were Screened With Both Probes

!- 2 ~of 54 Indications.Only the .540 Screened .

j 1 of 54 Indications Only the .510 Screened i

- No Change in Ultimate Disposition of Any Tubes Using

.510 vs. 540 Probe
- Probe Sizes of.510 To .540 Capable of Detecting ID i Flaws Smaller Than Critical Crack Size yv=' ym-vw w e-w T q w es ww- -ogg-w g w -g -r y- %we-+w-e---r-ra7T-t--*w- - * -wNvs ws e=-e> w wt49--C* r e e-e 4-*-'we w *w = vT -mu e e w 1**f-rtM'e C-Tt e T' e w N9--**-w'Me"-Nm**w-tem twTiwe'--tvi vww---, m-w v T- -w 9 f- *NF="*-P--^MT*"- F -

---em - -

I - ..

s .

l Changed From 8x1 to MRPC for Confirmation 4

l

- MRPC Length Measurement Compared to 8x1 Performance f .

MRPC-Provides. Additional InfOrmation of Flaw Geometry

~

j -

MRPC Provides Preferential ECT Field Coverage With Smaller Coils t ..,g -'

(More SeneMive to Very Small Indications)

~

! -- MRPC Provides More Consistent ECT Field ~ Coverage

. (No Gaps Between CoilFields) ,

l ,

~

) .

t

-- Rotating Probe Recognized As Probe of Choice by Industry g

e

e j i j .

j- .

L Software Changes s

4 l'. -

Many Improvements Since.198.4 i Improved Monitors and Screening Capability ~

'I

! Improved Presentations-MRPC; Terrain Maps Data Is Recorded in Digital Format Vs Analog Format t P w----y -,-- = -.,p.. ,, . _ , _,, , ,__ _

~

[ .

1 .

Personnel i

i i

l

- Site' Specific Trsining and Testing

- QDA.(Qualified- Data Analyst) Program Per EPRI Inspection Guidelines i

! - Improved Data Analysis Guidelines. _

e s

= -w= **- , - w v+ $,-v., , , . , , _ . , . _ _ , , . . . .

1 4

y; -

l TMI-1 OTSG Program l- Presentation Highlights s

i t Demonstrate That:

BVC Class Indications Are Structurally Insignificant Using the Structural Justification for the NUREG-1019 Approved ECT Program l

OTSG Inspection Scope Need Not Include the Kinetic Expansion Zone r

e une grg<w m- e v e =w- w--w-sese --r-=,9=,n- - ww.w,- -s e m -- %n,r.%,,ww.-,-w-,,-%s--,,.,.=s,-m---- w -w ww --e-n-,--va ,.4-o w- v -g ,,,e w,,.---w=-- m. ,-weww-,-mey, u 4,,-w,e +-,%-+w u - we's** v*-*- = ,, - - --,c- ,r,

I j

! TMI-1 OTSG Safety Requirements l - Detection ofPre-Critical Crack Is the Key Safety Requirement i

! - Detection by ECT ,

) ,

Cracks Which Are Large Enough to Propagate to Failure During i Normal Operation or During Design Basis Accidents Can Be Detected and Removed From Service (NUREG-1019) 1 .

Fatigue Cra'ck GrowthIs Gradual i Defects Remain Structurally Insignificant for a Long Time

. The BVC Tube Class Is Not an Exception

.- Circumferential Extent _< 0.5" Re-Inspected Each Outage i

l

_ . _ _ _ . . . . . . _ _ _ . . _ ~ _ . . _ _

1 j

i k

i l

k( I' 8 V

k* -

v

/.4 g

. e.1 - 4 O.8 - s i

"" \,.

.1 - 3 - ..

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$* h g yg.

i -

JtCT E ,

C$ , re trot s

- 2 ,- WM ,

' 'WFh N

9 f,4 l ,

V!:ru)

C. 3 i

.j -

0.2 i

0.I ,

0.3 0 20 40 Sa io m %r:w.

CE4 ULT $ of PAtvoCUS. ArtAt.13ts OF S TR uctuttA L SicsHtFtG A Ncs are CGFEcr.i. .

O e

e 9

9 4 ,

8

i

TMI-1 'OTSG S~afety Requirements (Cont'D)

~

i - -

Detection by Leakage .

(

i -

. Through-Wall Defects-Which May Propagate During Operation

.(Inchiding Heat-up/Codl-Down Cycles) Can Be Detected Well Below the Threshold Size That Could Fail During MSLB

~

(NUREG-1019). The BVC Tube Class .Is Not an Exception.

~

Operating Procedures Provide for Leak Monitoring and Trending During Power Operation'and Cooldowns. .

~

0.1 gpm Primary /Sec6ndary Leakage Above Baseline Is the Operating Limit During Power Operation.

l .

o

.,--.---.---.wo ,3, - - . . , .,,,-_.-_..,,,-,--,,,._.--,-,~.,-m,~, ,,-..w,~.---. . ..- - . ..',,m., -.-,-....wm., - . , . . - - . , . . _ , - . %_ . v - -, -, v

I 1

i j ,

l TMI-1 OTSG Flaw Tolerance Conservatisms l

j - Conservatisms in Flaw Tolerance Assessments

\ -

! MSLB Loads l Recent Analysis Results Show That Accident Loads Are Reduced i by About 20% From 3140 lbs to 2400 lbs.

4 Cooldown foads .

Assessment of OTSG Tube Loads During Cooldowns (Since

Restart After OTSG Tube Repairs) Indicate That Loads Range i Between 50 to 75% ofThose Used in Previous Flaw Tolerance and Growtl1 Assessments e

- ~

i .

\ .

\ .

l TMI-1 OTSG BVC Conclusion

(

i

~

! Conclusion-

'~

i The BVC- Class Indication Which Are Limited in l

~

Circumferential Extent to 40%

to 43%-(3 Degree Change.With 1-ID (l. Degree Increase With No Voltage Change,0.95 Volts), , '

~

~

No Voltage Change,1.81 Volts) 1- OD (4 Degree and 0.26 Volts

~

Increase,1.16 Volts) .

i 2.- for TSP Fretting 1 -ID Indication From 12% Sample (7.40 Volts) ,

w.

m - w- -, m,=- wr m d _i=-w- -+ , m w ,,wp3.% .-g,-w---m ,,.mm,,-upe- g g is, c-gw,- y g v--y,=g--w vsy--w- w-y-up-g-- gw%,y,gm,--w9m--w-- -g g-*--gym-+g-< w4 ep me ap e -twv' 3 99g g=-T-+v7

l .

~

^

I =

f 1

t

- Leak Tests

! . ' Bubble and~ Drip Tests in 11R Identified Only Leaking Plugs.

No Tub'e Leaks ~Were-Detected.

1 -

I ~

- Drip Tests in 10R Identified Only Leaking ~ Plugs.

! - No Tube ~ Leaks Were Detected.

i .

e f a

~ ~

i

~

)

T F

- - - , e- . . , ,w- w,._~-,.n.,,,,.,__.,,.,,,.,.,,,,,_--

4 1 .

l i

i,

  • 2 l

i

~

Outage 12R Plans l .

~

> ~- hiservice Tubes - 40 % .

i UsingBobbin Coil Probe (Tubes Will Be Assigned 3%,6%,12%, or Additional Label Prior to the Start of Outage for Determining-C-1, C-2, or C-3 Results Category) 1

-. KE Transitions 21 %

~

l Using Rotating; Probe.

- Sleeves 21 %

Using + Point and Bobbin Probes e

9 gws twmm-,---eww--- -e--e+-*~ews--e---r=---t-rv- s -,-t~---**-a.- w---v 'we-se=e-dw-s s= = w e v r .w e ww w s w -* +w-+e w ww---==*-s -wew wi-+w -we-+-- u -t we- s :-w- ser- 3-e+sw--wte+++-+,--eev-mws e wwww w *-+*-=-w==,te-i w-w -'T' V-*4" ~ ' - ' w--- +'v-- 1

l l

I i

.' Sample Expansion Criteria i

= 40% Sample - Expand Per Technical Specifications *

. Sleeves - Expand to 100% on Detection of Crack Like

Indication (in Pressure Boundary of Sleeve / Tube)
= Expansion Transitions - Expand Per Tech Specification
  • 4 1

l.

I-

  • Using an Interpretation Previously Approved by NRC l

i.._-.

I t

MEETING

SUMMARY

o TMI OTSG Inspection and repair program meets TS Requirements.

l o TMI OTSG tube repair criteria are consistent with that reviewed and approved by i NRC in NUREG-1019 and TMI-1 TS Amendment #103.

4 o Continued monitoring ofID indications show consistency with 1981 damage mechanism.

i o TMI:OTSG tubing integrity within the tubesheets is assured by:

Frequent leak tests & operational leakage monitoring ECT in'spection from LTS roll transition to UTS kinetic expansion transition I

MRPC ECT inspection oflane/ wedge kinetic expansion transitions during 11R

! Design & qualification of kinetic expansion process performed at TMI-1 9

6

.w--,--_. -.3_- - , - . - - - - , . - , , , - , - , . .-.,_,...,,-,,_.,_.,,~.----.-_.,,,_.-._,-.-.~,,,ymm , __%---, . .- . , . . , . . m. , . , ,- --. . - - - - - - -i%. - , - . - ,. ,

i-l 4

MEETING SEMMARY i

i, l

12R (September '97) ECT inspections:

Comprehensive planned scope

(including 21% MRPC exam of kinetic expansion transitions) '

l Use of appropriate ECT probe types / techniques I

i 1

I l

l l

Table ofNomenclature  !

BVC = Below Voltage Criterion l DTS =

Distorted Tubesheet Signal ECT =

Eddy Current Testing 1 -

EOL =

End Of Life l HCF =

High Cycle Fatigue HF = High Frequency 4 -

I-690 = Inconel 690 alloy  ;

I.D. = Inside Diameter IGA = IntergranularAttack f

IGSAC =

Intergranular Stress Assisted Cracking IGSCC =

Intergranular Stress Corrosion Cracking I

- KE = Kinetic Expansion K.E.T. = Kinetic ExpansionTransition LTS = LowerTubeSheet MR = Mid Range MRPC = Motorized Rotating Pancake Coil

- MSLB = Main Steam Line Break .

NDD = No Detectable Degradation

~

O.D. = Outside Diameter OTSG = Once Through Steam Generator

~

P/S = Primary-to-Secondary -

PSLR = Primary-to-Secondary Leak Rate QDA = Qualified Data Analyst RCPB = Reactor Coolant Pressure Boundary RMSE = Root Mean Square Error SG = Steam Generator S/N = Signal-to-Noise Ratio -

TSP = Tube Support Plate  !

- T.W. = Through Wall UTS = UpperTube Sheet

.

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