ML19211A245
| ML19211A245 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 11/05/1979 |
| From: | Counsil W, Fee W CONNECTICUT YANKEE ATOMIC POWER CO. |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| IEB-79-13, NUDOCS 7912170244 | |
| Download: ML19211A245 (5) | |
Text
e CONNECTICUT YANKEE ATOMIC POWER COMPANY 7A BERLdN. CO N N ECTIC U T P.O. WOR 370 H ARTFORD. CON N ECTICUT 00101 2036868999 November 5, 1979 Docket No. 50-213 Mr. Boyce H. Grier, Director Region I Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406
Reference:
(1)
B. H. Grier letter to W. G. Counsil dated June 25, 1979, transmitting I6E Bulletin No. 79-13.
Gentlemen:
Haddam Neck Plant Feedwater System Piping In Reference (1), the NRC Staf f documented its requirements regarding investiga-tions and examinations of feedwater system piping which were applicable to the Haddam Neck Plant. With the docketing of Attachment 1, A Summary Report of the NRC I&E Bulletin No. 79-13 Inspection Results, Connecticut Yankee Atomic Power Company (CYAPCO) has fulfilled the requirements of Item (6) of Reference (1).
os rtated in the conclusion section of the Attachment, the investigations cc.picted to date have not identified any unacceptable components of the feedwater system piping at the Haddam Neck Plant.
We trust you find the attached information responsive to your request.
Very truly yours, CONNECliCUT YANKEE ATOMIC POWER COMPANY W. G.(/tounsil Vice President Attachment A
By:
W. F. Fee Vice President 7912170 2 4 4
DOCKET NO. 50-213 l
ATTACifMENT
!!ADDAM NECK PLANT A
SUMMARY
REPORT OF TiiE NRC I&E BULLETIN No. 79-13 INSPECTION RESULTS 1591 200 NOVEMBER, 1979
1.0 INTRODUCTION
Plant cooldown was commenced at Connecticut Yankee on September 28, 1979, to perform the inspections of (1) the steam generator feedwater nozzle to elbow welds and (2) the feedwater system piping supports and snubbers inside containment as required by NRC IE Bulletin 79-13.
The volumetric inspec-tions of the steam generator feedwater nozzle to elbow welds and subsequent evaluation of the inspection results were completed on Octcher 2,1979.
The visual inspection of the feedwater system piping supports and snubbers was completed on October 4,1979.
2.0 PURPOSE The purpcsc of this report is to present a summary of the inspection results in accordance with Item 6 of IE Bulletin 79-13 dated June 25, 1979 3.0 DISCUSSION The feedwater piping system inside containment was fabricated in accordance with the American Standard Code for Pressure Piping, ASA B31.1.
In addition, all field welds in the feedwater piping system were 100 percent radiographed.
The steam generator feodwater nozzle to elbow welds are 14" sch. 80, while the remaining feedwater system piping is 12" sch. 80.
The steam generator feedwater nozzle / pipe configuration consists of the feedwater nozzle to 14" x 12" reducing elbow and subsequent 12" piping.
The steam generator feedwater nozzle material is ASTM A-105, Grade II, material, while the reducing elbow and remaining feedwater piping materials are ASTM A-234 WPB (fi ttings) and ASTM A-106, Grade B, materials, respectively.
A review of the original radiographs and the applicable specifications confirmed that the steam generator feedwater nozzle to cibow welds were singic V-butt weld joints including mtallic backing rings. The weld joints are equal thickness joints since no counterbore/ machining is evident in the radiographs.
4.0 INSPECTION RESULTS 4.1 Steam Generator Feedwater Nozzle to Elbow Welds 4.1.1 The steam generator feedwater nozzle to elbow welds were examined by qualified Peabody Testing Corporation personnel in accordance with the requirements of Item 1 in NRC IE Bulletin 79-13 dated June 25, 1979.
The evaluation of the RT inspection results was performed by Westinghouse, NUSCO, and CY personnel. An authorized code inspector was present 1591 201
2 to witness the steam generator feedwater nozzle to cibow inspection and subsequent evaluation of the inspection results.
The evaluation acceptance criteria was in accordance with ASME Section III, Subsection NC, Article NC-S000.
4.1.2 The summary of the NRC IE Bulletin 79-13 exx:11na tion results is presented below:
A.
Steam Generator Fecdwater Nozzle to Elbow Weld (SG-E-6-1-1) 1.
2Wo short in-line linear indications exist at the weld root centerline.
The same indications exist in the original acceptance radiographs.
The dimensions of the linear indications are the same as in the original acceptance radiographs and therefore they have not propagated during operation since 1967.
F:2rthermore, the linear is,11 cation are within the acceptance criteria of ASME III-S320 and thus do not constitute unacceptable code discontinuities.
2.
Parallel lines extending circumferential1y were observed in the nozzle base material.
The observed lines exist in the original radiographs at the same locations.
The parallel lines were confirmed to be OD indications; they appear to be grinding and/or machining marks on the nozzle OD.
B.
Steam Generator Feedwater Nozzle to Elbow Welds (SG-E-6-2-1, SG-E-6-3-1, SG-E-6-4-1)
The existence of parallel / single lines was observed on the nozzle side of the above nozzle to elbow welds.
All observed indications exist to some extent at the same locations in the original radiographs.
The observed indications are grinding and/or machining marks on the nozzle OD.
Based on the evaluation performed by Westinghouse, Connecticut Yankee and NUSCO personnel, it is concluded that no cracking as observed at other PWR units nor other unacceptable code discontinulties were detected in the steam generator feedwater nozzle to elbow welds and adjacent base material at Connecticut Yankee.
4.2 Feedwater System Piping Supports and Snubbers All feedwater piping supports and snubbers inside containment were visually inspected for operability and conformance to design. Some disprepancies were identified, reviewed, and dispositioned under the IE Bulletin 79-02 and 79-14 programs.
These discrepancies were of little consequence and did not affect the operability of the feedwater pipe support system.
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3 S.0 CONCLUSION 5.1 No cracking as observed at other PWR units was detected in the steam generator feedwater nozzle to elbow welds and adjacent base ntaterial at Connecticut Yankee.
5.2 No unacceptable code discontinuities exist in the steam generator feedwater nozzle to elbow welds at Connecticut Yankee.
S.3 The feedwater piping supports and snubbers inside containnent were confirred to be operable and in conformance with design requirement =.
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