ML17207A785
| ML17207A785 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 01/25/1980 |
| From: | FLORIDA POWER & LIGHT CO. |
| To: | |
| Shared Package | |
| ML17207A784 | List: |
| References | |
| NUDOCS 8002040483 | |
| Download: ML17207A785 (5) | |
Text
INTERIM DEFICXENCY REPORT SAFETY RELATED FLANGE RATXNG NAME OF STATION:
'T. LUCIE PLANT UNIT 2 OWNER:
FLORIDA POWER
& LIGHT COMPANY ARCHITECT/ENGINEER:
EBASCO SERVICES, INCORPORATED NUCLEAR STEAM SYSTEM SUPPLIER (NSSS):
COMBUSTION ENGXNEERING, INC.
DATE OF DEFICXENCY:
DECEMBER 21, 1979 INTERXM REPORT FILED:
JANUARY 25, 19 80 pppgp4p /EZ
I
~Summar During a normal design review process it was noted that. the flange material for various safety related systems was specified equivalent to the pipe material (304SS) in lieu of the connecting pump or valve flange material (316SS).
Since the ANSI B16.5-1968 pressure and temperature ratings for flanges are dependent upon the types of austenitic stainless steels specified, a review of all safety related stainless steel systems was performed to determine the adequacy of utilizing 304SS flanges.
It was determined that the specified system design pressures and temperatures for some 304SS flanges may exceed the AS'ode,Section XXX Paragraph NC 3612.1 standard flange ratings.
Per the requirements of 10CFR50.55(e) the event was deemed potentially reportable and per telecon, FP&L notified the NRC on December 21, 1979 of such.
This interim report is being submitted to advise the NRC of the status of this review.
St. Lucie Unit 2 is designed per the requirements of ASME Code,Section XII, 1971 Edition through Summer 1973 addenda, which references the requirements of ASMI B16.5-1968 code.
The ANSX B16.5-1968 code pro-vides acceptable temperature and pressure ratings for all flanges in lieu of alternative flange analysis.
The ANSI B16.5-1968 code allow-ables for 304SS are lower than the allowables for 316SS.
During a normal design review process it was noted that the flange material for various safety related systems was specified equivalent to the pipe material (304SS) in lieu of the connecting pump or valve
flange material (316SS)
This discrepancy as far as our invest-igation has identified is a result of the particular St. Lucie Unit 2 interface between the NSSS and the A/E in regard to res-ponsibilities of the NSSS design.
The nuclear steam supplier is responsible for the NSSS design and system criteria, whereas the A/E is responsible for the piping layout and stress analysis.
Therefore, all NSSS safety related systems in question utilizing austenitic stainless steel material were examined to determine if there was any discrepancy in material selection in accordance with the code.
In all cases, the maximum operating and design temperatures and pressures as specified were initially compared with the ANSI B16.5-1968 code allowable ratings.
A summary of the status is tabulated below.
~Ss tern Safety Injection Reactor coolant Chem a Volume Control No. of Flanges A'cce table 30 18 112 No. of Flanges Questionable 115 76 36 Sampling Fuel Pool Waste Management Containmnet, Spray TOTAL All All All 172 234 It should be noted that the flanges indicated as questionable above have been found for 2 1/2 inches and larger to have a rating above the maximum. operating pressure and temperature allowables per ANSI B16.5-1968.
We are presently conducting flange analysis to identify if there are any actual deficiencies in these systems.
II DESCRIPTION (Cont'd.)
A breakdown of the number of flanges in question are as follows:
53 181 24 inches and larger 2 inches and smaller The status as of January 25, 1980 of design/fabrication/
installation is as follows:
2 inches and smaller 105 flanges 76 flanges Random Stock Supply Appear on isometrics already prepared Isometrics have not yet been prepared Material Status 57<
Installed (estimate) 24 inches and lar er 53 flanges All isometrics are already prepared All spools rec'd Material status ll flanges Installed (on 8 spools)
c.
XXX CORRECTIVE ACTION Upon completion of the aforementioned review, the corrective action will be either to prove acceptability of the flanges or replacement.
Presently we -are=proceedin'g as follows 2 inches and under Xn lieu of flange analysis and based upon material avail-ability and construction
- schedule, we have elected to proceed with replacement flanges.
The 304SS flanges will either be replaced with an equivalent 316SS flange or with a 304SS flange of a higher ANSI rating.
24 inches and lar er We. have elected to do flange analysis due to material avail-ability and construction schedule to determine the acceptability of the specified flanges in question.
Xn parallel, we are investigating recent material availability and will issue a
"hold" on further installation of the larger bore flanges in question.
Upon completion of the analysis, a decision will be made as to whether flange replacement is necessary.
XV SAFETY IMPLXCATIONS This situation was deemed potentially reportable.
If the above described review results in identification of a deficiency and was to have remained uncorrected, the corresponding system may not. have been adequate to perform its intended safety function.
V CONCLUSION A final report will be submitted by May 1, 1980 with the results of the review and necessary actions taken.