ML20058A352
| ML20058A352 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 10/16/1990 |
| From: | Israel S NRC OFFICE FOR ANALYSIS & EVALUATION OF OPERATIONAL DATA (AEOD) |
| To: | Rosenthal J NRC OFFICE FOR ANALYSIS & EVALUATION OF OPERATIONAL DATA (AEOD) |
| Shared Package | |
| ML17348A608 | List: |
| References | |
| AEOD-T90-14, NUDOCS 9010260016 | |
| Download: ML20058A352 (2) | |
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' UNITED STATES
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NUCLEAR REGULATORY COMMISSION i
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WASHINGTON, D. C. 20555 j
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00T 101990
- MEMORANDTH FOR:
Jack E. Rosenthal, Chief Reactor Operations Analysis B.noch Division of Safety Programs Office for Analysis and Evaluation of Operational Data i
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Sanford Israel Reactor Systems Section E and B&W Reactor Operations Analysis Branch Division of S tfety Programs Office for Analysis and Evaluation t
of Onerational Data
SUBJECT:
SEAL PROBLEMS IN BORIC ACID TRANSFER PUMPS The enclosed technical review report on seal problems in boric acid transfer pumps discusses insights on pump seals and seal water systems obtained from discussions with several licensee personnel, it appears that the seal water problem at Turkey Point may be unique to that plant. Other plants sumycd use single mechanical seals which do not require scal water systems. The major safety concern associated with the seal water system at Turkey Point is uncontrolled intrusion of nitrogen into the boric acid system. This issue was previously.
highlighted in an information notice and the licensee has instituted administrative procedures 3
to isolate the nitrogen supply after filling and pressurizing the seal water system.
7 Mechanical seals are designed with nominal leakage to lubricate the rubbing seal faces. The expected lifetime of a mechanical seal is one to two yee ri before it leaks excessively.
Discussions with utility personnel indicate that this lenahe can be a significant housekeeping and maintenance chore Most of the persons contactec said they wanted to reduce their boric acid systems to 4 w/o boric acid to reduce the maintena.tce effort on these systems. In fact, one utility is switching to sealless pumps as part of their wxlification to 4 w/o boric acid.
This should eliminate pump leakage ane 'he associated maintenance.
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Jack E. Rosenthal l My analysis does not indicate an important generic safety issue concerning the seals in boric acid transfer pumps. However, chronic leakage associated with mechanical seals may pose a j
concern for ECCS pumps that are needed to provide long term cooling following a LOCA.
This issue was part of the TMI Action Plan, but it may warrant a limited investigation to understand the potential impact of leakage from these pumps, i
Origing signed by j
Sanford Israel Reactoi 'iystams Section E and B&W Reactor Op..> ions Analysis Branch Division o~ Safety Programs Office for A..alysis and Evaluation of Oper tional Data cc w/ enclosure: G. Edison, NRR D_i.stribution:
];PDRf Elordan MWilhams Central File Dross KBlack ROAB R/F TNovak RSavio, ACRS i
DSP R/F VBenaroya MTaylor, EDO SIsrael LSpessard KRaglin, TTC PLam GZech,
AChaffee, NRR JRosenthal SRubin 4
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