ML19296D671
| ML19296D671 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 02/07/1980 |
| From: | Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| NUDOCS 8003120746 | |
| Download: ML19296D671 (2) | |
Text
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PHILADELPHIA ELECTRIC COMPANY 23O1 M ARKET STREET P.O. BOX 8699 PHILADELPHI A. PA.19101 1215)841 4000 February 7,
1980 Dochet Nos. 50-277 50-278 Mr. Royce H.
Grier, Director Office of Inspection & Enforcement Region I U.S.
Nuclear Re gu la t ory Commission 631 Park Avenue King of Prussia, PA 19406
Dear Mr. Grier:
This letter is to provide you uith inf orma tion concerning recent support nodifications to tuo Peach Bottoc Unit 3 level sensing lines on the reactor and to review the status of the comparable sensing lines on Unit 2.
As a result of the analy tical engineering e va lu a t i on s being p erf orne d for Bulletin 79-14, it was deternined that the two level sensing lines as inspected on the Unit 3 reactor uere well within the current operability criteria for seisnic loading stresses, and a ls o met the FSAR stress criteria f or an operating basis earthquake: however the lines did not meet the specific s
FSAR stress criteria for the design basis earthquake (DBE).
The criteria for determininq systen operability used by our architect engineer is 2.4 times Sh which is the allowable stress in the h ot condition (Sh is btained from ANSI B31.1 Piping Code).
This criteria is the allowable stress for DOE loading contained in the current ASME Boiler and Pressure Vessel Code,Section III, Subsection NC.
Our architect entineer advises that this present day criteria can be applied t o Peach Sottom as a criteria for operability since the originally installed construction naterials have not changed significantly.
Even though the DBE stress value did not meet the FSAR criteria, it was less than 2.4 S and therefore fell within the criteria for h
800312g /g
Mr. H oy c e H.
Grier Page 2 operability.
A lt h ou gh in piping applications of this type the actual failure stress can only be determined by test, it should be noted that the ultinate strength for the piping material of 75,000 psi is a factor of greater than two times the stress calculated p rior to modification.
Ue took advantage of a recent Unit 3 naintenance outage during which support modifications were completed on the sensing lines.
The modifications were completed on February 3,
1980, and the lines now meet the FSAR DBE stress criteria.
The Unit 2 piping has not yet been inspected and measured under the 79-14 program.
However, all remaining work associated with Bulletin 79-14 will be c omp le t e d during the upcoming refueling /naintenance outage s ch ed u le d to begin on March
- 21. 1980.
He have hi h confidence that the Unit 2 sensing lines 3
neet the operability criteria and therefore, continued op eration of the Unit will not have an adve rs e effect on the health and safety of the public.
Very t ru ly y ou rs.
G HV J.
Cooney uperintendent Generation Division / Nuclear LAH:bam cc:
United States Muclear Regulatory Conmission Office of Inspection and Enforcement Division of Reactor Operations Inspection Unshington, DC 20555