ML20009F674
| ML20009F674 | |
| Person / Time | |
|---|---|
| Site: | Cherokee  |
| Issue date: | 07/14/1981 |
| From: | Dail L DUKE POWER CO. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, NUDOCS 8107310398 | |
| Download: ML20009F674 (2) | |
Text
-..
PPICIAL copy *,
o'
'NP DUKE PO.WEH COMPANY Cp GENEllAL OFFICES
- ' ["," fff"4N' 422 SOUTH CHURCH STREET J
CIIAltLOTfE N. C. 28242 0 / lll:
i '
2/
4g,,
July 14,1981 Mr. J. P. O'Reilly, Director U. S. Nuclear Regulatory Comission j
101 Marietta Street, Suite 3100 l
,\\g1lj Atlanta, GA 30303 s
$ ? K}\\[7) /
fi:.ult) L
~'5 Re:
Cherokee Nuclear Station, Unit 1 6-Docket No. 50-491 C
JUL r 01981* T N,,s.,muu **',3j IE 81/01-5PS-491 y/
NSSS-Shutdown Heat Exchanger Duke Files:
P81-1201.00, P81-1201.06 ej cn
Dear Mr. O'Reilly:
Attached is Duke's progress report on the referenced 10CFR 50.55(e) reportable item. Another report will be submitted by October 1, 1981.
Initial notification was made by telephone to Mr. Rausch of your office on December 17, 1980. An interim report was submitted to your office on January 15, 1981, Very truly yours, 9
(
L. C. Dail, Vice-President Design Engineering Department GDR/pam Attachment cc:
Director of Inspection & Enforcement U. S. Nuclear Regulatory Comission Washington, DC 20555 g
t
~
hI l 8107310398 810714 PDR ADOCK 05000491 S
r o
DUKE POWER CO.
CHEROKEE NUCLEAR STATION Report Number:
IE 81/01-5PS-491, (Progress Report)
Report Date:
January 15, 1981 (initial)
Facility:
Cherokee Nuclear Station - Unit #1 Restatement of Deficiency:
Apparent breakdowns in manufacturing, cleaning, and Inspection processes on Shutdown Heat Exchangers (SDHX's)
Description of Deficiency:
On December 17, 1980, Mr. R. E. Miller and Mr. W. H. Bradley informed Mr. John Rausch, NRC of potential deficiencies in the Shutdown Heat Exchangers, supplied by Combustion Engir-Ing as part of *.he NSSS contract, along the following lines.
~
1.
Due to problems encountered on the WPPSS Unit #3 SDHX, and since the Duke SDHX's were manufactured by the same vendor (Ametek), CE advised Duke that heat exchangers were suspect of similar deficiencies.
2.
Duke Unit #1 3DHX's were inspected at the site, and were found to have problems with the stainless steel cladding and contamination of tube side material surfaces.
Analysis of Safety implications:
Refer to initial report.
Update on Corrective Actions:
Duke removed the Unit IA and IB SDHX's from the Reactor Buil. ding, and returned them to the original supplier for examination and repair.
Results of the examina-tion of the SDHX's are as follows:
Unit IA:
I (1)
Unacceptable hardness readings and cracking will require recladding of the tube sheet, tubesheet to channel weld, and channel cover.
I Acceptable clad thickner.s will be verified by ultrasonic inspection
(
(UT).
i (2)
Minor unacceptable PT indications in areas not to be reclad will be corrected and re-PT'd.
(3)
Complete recubing will be required due to reciadding of the tube l
j sheet.
New tubing will be eddy current tested (ET) per revised l
CE procedure to assure no unacceptable defects.
(4)
Reworked heat exchangers will be cleaned, dried, and inspected j
following hydrotest to assure absence of surface contamination.
i i
l
Report Numbar:
IE 81/01-SPS-491 s
Progress R2 port Page 2.
Unit IB:
(1) All clad surfaces were found to be acceptable from an application (i.e. hardness) standpoint with the exception of a few minor unacceptable dye penetrant test (PT) indications.
These unacceptable indications will be corrected and re-PT'd.
(2)
Clad thickness was measured by UT technique for minimum thickness verification. Readings at ten points were found to be under the CE specified minimum.
CE accepted this condition based on accept-able SS thickness at the surface to accomplish required design life corrosion protection.
Acceptance of these exceptions to speci-fication will be documented by including an approved dev:ation from contract requirement (DCR) In.the QA documentation package.
(3)
Contamination of tubing internal surfaces was removed by power tool /
detergent cleaning.
ET to revised CE procedure was conducted with m, unacceptable indications.
The work identified above on Unit I A is in various stages of progress, and complete on Unit 18.
Unit 1B has been re-hydrotested, final cleaned with demineralized water, dried, nitrogen blanketed on tube and shell side, and has just recently been delivered to the Cherokee site.
Receipt inspection activities are underway and results will be available by 8-1-81.
Unit IA is scheduled to be completed and shipped by 8-31-81. A full report to the NRC on the causes of the, deficiencies identified and details on the corrective actions taken is tentatively scheduled to be available by 10-1-81.
JCS/ser I
i l
l l
i r
i k
l
--w-+,v w,w w w e-
-ww~,ww w--4.,mww.
4-,r---+-,-w
--,t+---,--e-~ew-v~treve-----,--+-=e
---w,,
w---e,y--*----y+-ewy,*,"e
-- +
g---
v----
+, - -. -*-+-
v