ML20197H841
| ML20197H841 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 12/17/1997 |
| From: | Langenbach J GENERAL PUBLIC UTILITIES CORP. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 6710-97-2484, NUDOCS 9801020011 | |
| Download: ML20197H841 (6) | |
Text
.-.y
- m. _ -
~,..,. _. - _ _ _ _. - _. _ -. - -._
+.J@ l*
a:
e, j
t c
= GPU Nucleer, Inc.-
"lG..
[ NUCLEAR J-
' Route 441 South j
r
- D"'c ' * * ** -
1 Middletown, PA 17057 0400 Tel 717 944 7621 -
4 I
December 17, 1997 i
h 6710-97-2484
}
f 44
> U.Sl Nuclear Regulatory Commission :
, ? Attn:~ Document Control Desk 1 Washington,DC. 20555 Gentlemen:
3
Subject:
Three Mile Island Nuclear Station, Unit 1 (TMI-1)
Docket No. 50-289
^
Operating License No. DPR-50 NRC Noti 6 cation on Completion of 12R Outage Steam Generator Examinations a
' TMI-l Technical SpeciDcations 4.19.5.a requires that GPU Nuclear notify the NRC after the completion of each inservice inspection of steam generator tubes, prior to exceeding a reactor coolant system temperature of 250 F of the following:
- 1) - iThe number of tubes repaired or removed from service in each steam generator,
- 2) : An assessmeat of the growth ofinside diameter intergranular attack (IGA) degradation, and.
- 3) Results ofin-situ pressure testing, if performed.
Attachment i provides a summary of the October 9,1997 telephone notincation which satis 6ed the Technical Speci6 cation (TS) 4.19.5.a requirements after the completion of the Cycle 12 Refueling (12R) Outage inservice inspection of the TMI-l Steam Generators. provides eddy current examination results for the two full length tubes that were.
removed from the TMI-l steam generators during the 12R outage. Tube number A52-34 was pulled from ths "A" generator and tube number B91-55 was pulled from the "B" generator.
included are the bobbin coil and ' motorized pancake coil (MRPC) eddy current test (ECT) data which were used for selecting the tubes for removal.: In a July 15,1997 meeting with GPU
- Nuclear, the NRC staff requested that GPU Nuclear submit these data prior to performing the laborttory destructive examinations. In addition to there results, data from examinations using
. other probes (e g.', 0.510" mid-frequency and tuned bobbin, 0.540" mid-frequency, CECCO, and LMICA), prior to tube removal, are available at the site for NRC review.
M102oolf971a17.,"
l>
anocx o.oooa P-PDR 2
.a -
4
' 6710-97 2484 Page 2 of 2 in accordance with TS 4.19.5.b, the GPU Nuclear report of the complete results from the TMI-l 12R Outage steam generator tube inservice inspections will be provided by January 13,1998.
The report will contain an hiRPC-based growth rate study of the indications and a more detailed discussion of growth rate based on bobbin coil examinations. Examination results from the tube pull specimens will not be available by that date. We expect to submit the results of tube pull examinations as they relate to the condition monitoring and operational assessment by June 1,1998.
Sincerely,
_p@
dudI4
(
O James W. Langenbach Vice President and Director, Thil MRK Attachments cc:
Administrator, NRC Region 1 TMl Senior NRC Resident inspector TMI-l Senior NRC Project Manager llll.l!".Ill,l!ll: cI
'I 6710-97-2484, Page1of1 Notification Summary - Completion of 12R Outage Tube Examinations
- 1) Thcliumber of tubes repaired or removedJins service in each steam gene _talot" Thirty-one (31) tubes were removed from service in the TM1 1 "A" OTSG es a result of the 12R Outage eddy current examinations. Of:he original 15,531 tubes in the "A"_OTSG,1300 (8.4%) of the tubes are now removed from service. 248 tubes in the "A" OTSG remain in service that were sleeved in previous outages.
Seventeen (17) tubes were removed from service m the TMI-l "B" OTSG es a result of the 12R Outage eddy current exams. Of the original 15,531 tubes in the "B" OTSG,395 (2.5%)
of the tubes are now removed from service. 253 tubes in the "B" OTSG remain in service that were sleeved in previous outages.
i
~ 2) Atagessment of growth ofinside diameter IGA degradation:
GPU Nuclear completed eddy current examinations of all in-service tubes during the 12R Outage. The results show that the apparent growth rate of the ID IGA flaws'is very low (if any) and is within the normal variability of the bobbin coil eddy current process. For example, the mean bobbin coil voltage change from IIR to 12R for ID IGA flaws in both generators was +0.08 Volts for the 388 indicat ons used in the analysis. This is compared i
with the mean bobbin coil voltage change for 197 ID IGA indications from 10R to llR which was -0.26 volts as presented in our August 1,1996 submittal of" Cycle 11 Refueling (11R) Outage Once Through Steam Generator (OTSG) Tube Inspection Report with ASME Form NIS-1 Covering the 11R OTSG Inservice Inspections "
- 3) Results orin-situ p2 essure tetting. if r,erformed:
In situ pressure tests were conducted in accordance with the EPRI guidelines for performing in-situ testing of steam generator tubes. Two tubes were tested in the "A" OTSO (A93-119 and A107-120). Five tubes were in-situ pressure tested in "B" OTSG (B58-13, B79-58, B79-60, B t 18-38, and B134-19). A list of the tubes and indications that were tested was provided in a table attached to our Octc5er 10,1997 submittal, " Additional Information to Support Technical Specification Change Request (TSCR) No. 268 - 01 SG Inspection Criteria for 12R Examinations." Each of these tubes was plugged following the test.
No leakage was observed daring any of the in-situ pressure tests (4400 psig). The minimum detectable leakage rate was 0.0005 gpm.
~
6710 97 2484
~
l Page1of3 TMI-l 12R Eddy Current Examination Data for Pulled Tube A52-34 Location Type of Type of Voltage -
Phase Percent Axial Cire.
(*
- See ECT Indication (Volts)
Angle Through-Extent Extent Note)
Probe De rees Wall ummmmmmmmmmenummmmmmmmum
.a unummmmmmumnummy,---
.540" 15 + 38.2" Bobbin ID 0.7 5
17 %
hiRPC VOL 1.0 359 0.10" 0.06"
.540" 15 + 24.9" Bobbin BVC 0.8 I8 hiRPC VOL 1.5 352 0.10" 0.11" ummmmmmmmmmme mummmmmmmmmmumummmmmmmmmmuummmmmmmmmum x-
.540" 15 + 14.7" Bobbin BVC 0.7 20 h1RPC VOL 1.2 3
0.10" 0.06" mmmmmmmmmmmummummmmmmumummmmmmmmmmesummmmmmmmummmmmmmmann---
.540" 15 + 4.6" Bobbin BVC 0.6 7
MRPC VOL-1.3 351 0.10" 0.11" ummmmmmmmmmmu mumumummmmmmmannummemumsammmmmmmmmmumnummmmmmar a+~~-========
.540" 14 + 31.9" Bobbin BVC 0.9 17 hiRPC VOL 1.2 4
0.16" 0.11" mummmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmusumusumummme================================="r======
.540" 14 + 22.5" Bobbin BVC 0.7 1i hiRPC VOL 1.1 1
0.10" 0.14" numummmmmmmmmunummmmmmmmu===========
r-
.540" 14 + 20.0" Bobbin BVC 0.7 16 h1RPC VOL 0.9 359
- 0. 0 5.".---- 0.06" --.
mummmmmmmmmmmm-
-o
..... ~
.540" 14 + 12.8" Bobbin INR 1.3 3
MRPC VOL 0.8 1
016."
ma,_0.19" ammmmmmmmmunes
- m. -
VOL 1 1.--
18 0.16" 0.11" 14 + 3.1"
,,h,i,R,P,C,,,,,
m...
.. - ~.. _..,
m,_,.
!.540" 13 + 23.1^
Bobb:n ID 0.9 11 37%
hiRPC VOL 1.3 352 0.16" 0.11"
.s.. ~..
.m._..m_.__ _
.540" 13 + 2.9" Bobbin ID 0.9 15 50%
hiRPC VOL 1.8 356 0.10" 0.11"__ _ _
" Noig: Location is given as inches above the midplane of a partientar tube support plate (e.g.
15 + 4.6" is 4.6 inches above the midplane of the 15 tube suppon plate.)
_ ~ _
- 6710-97-2484 Page 2 of 3 TMI-l 12R Eddy Current Examination Data for Pulled Tube B91-55 Location I Type of Type of Voltage n'hase Percent Axial Circ.
(*
- See ECT Indication (Volts)
Angle Through-Extent Extent Probe g
.510" 15 + 40.7" Bobbin NQI 0.8 101 15 + 42.1" MRPC sal 1.4 47 0.3"
.510" 15 + 39.1" Bobbin NQI 0.9 100 15 + 40.3" MRPC SAI 1.3 45 0.2" maammmmumummamusumummmma maammm mmmmmummmmmmmmmemummmmmmmmu
.510" 15 + 37.9" Bobbin NQI 0.6 74 15 + 39.2" MRPC sal 1.5 51
- 0. 3" unummmmmmmmmummmmmmmmusummammmmmmmmmemummmmmmmmmmmmmmmmmmmunummmmmmmmm
.510" 15 + 35.6" Bobbin NQI 1.5 80 15 + 36.2" MRPC SAI 2.4 56 0.6"
-ummanumanum--v-~--
--mmmmmmmmmmm
.510" 15 + 7.6" Bobbin NQI 0.7 94 1567.2" MRPC SAI 0.8 43 0.2"
- Nntes:
1.
Location is given as inches above the midplane of a particular tube support plate (e.g.15 +
4.6" is 4.6 inches above the midplane of the 15* tube support plate.)
2.
The bobbin coil indications were recorded using the 400 kHz ditTerential channel which requires an " abrupt" flaw change to be present (in the axial direction) to produce a response.
The MRPC examination technique does not require such a change. Thus, for longer axial flaws the areas of flaw recording are not expected to occur at the same location for the two techniques; for this reason the axial flaw locations reported above for the bobbin and MRPC techniques are not identical.
,, j,:
.6710-97 24843
~ ' - Attachment 2 l
~ Page 3'of 3:
TMI 1 -12R Eddy Current Examination Data for Pulled Tube
(
' Nomencialuis:
- i BVC = Below Voltage Criteria L
- Circ Extent = Circumferential Measurement (in inches).
j
? ECT = Eddy Current Technique -
TID = Inside Diameter :
4 t INR = Indication Not Recordable.
L MRPC = Motorized Rotating Pancake Coil.
sNQI =. Non Quantifiable Indication
' sal = Single Axial Indication
- VOL = 1. D. Vohimetric 7
1
-P 1
4
.=
4 b
(
--r-*--
. =,
e v