ML18030A263

Interim Deficiency Rept Re Original Design of Diesel Generator Exhaust Lines,Initially Reported on 810123.Design Change Request 231 Issued.Third Exhaust Expansion Joint Added to Exhaust Lines.Final Rept During May 1981

ML18030A263
Person / Time
Site:	Susquehanna
Issue date:	04/16/1981
From:	Curtis N PENNSYLVANIA POWER & LIGHT CO.
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
10CFR-050.55E, 10CFR-50.55E, PLA-656, NUDOCS 8104210502
Download: ML18030A263 (5)

Text

REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:8104210502 DOC ~ DATES 81/04/16 NOTARIZED! NO DOCKET ¹ FACIL:50- Susquehanna 388 usquehanna Steam Electric Station~ Unit Steam Electric Station< Unit 2~ Pennsylva ii Pennsy.lva 05000387 05000388 0

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RECIP ~ NAME AUTHOR AFFII I ATION Pennsylvania Po~er 8, Ligt t Co.

RECIPIENT AFFILIATION GRIER p 8 ~ H ~ Region 1 i Phi adel phiaE 1 Office of the Oir ector

SUBJECT:

Inter im deficiency reot re original design of exhaust lines>initially reported on 810123 diesel'enerator

~ Design Change Request 831 issued. Third exhaust expansion joint added to exhaust lines ~ Final rept during May 1981 CODE>'OISS'OPIES RECEIVED:LTR I, ENCL J S I ZE t ~~~~~~~~~~ 'ISTRIBUTION TITLE! Construction Deficiency Report (iOCFR50'o55E)

NOTES:Send I8,E 3 copies FSAR 8 all 05000387 I8E 3 copies I-'SAR 8 all amends, amends'end 05000388 RECIPIENT COPIES RECIPIENT COPIES IO CODE/NAI;E LTTR ENCL, IO CODE/NAME LTTR ENCL ACTION! A/O LICENSNG 04 1 1 YOUNGBLOODgB 05 1, 1 RUSHBROOKOM, 06 1 STARKgR ~ 07 1, INTERNALS ASLBP'/ J;, HARD 1 1 D.'/DIR HUM FAC.15 1 1 EOO 8 STAFF 19 1, 1 EQUIP QUAL BR11 1 1 HYO/GEO BR 2C 1 I8E 09 1 1 IE/EFS" 1 1 LIC QUAI. BR 12 1

/PA 2v 1 NRC PDR 02 1 1 OELO 21 1 1 ~C-/-7%: 13 1 1 QA BR 14 1 1 REG FILE . 01 1 1 RUTHERFOROEN ~ IE 1 1 RD~ 21 1 1 ~

EXTERNAL! ACRS 16 16 16 LPDR 03 1. 1 NSIC 08 1 1 Apg 24 1893

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TOTAL NUEIBER OF COPIES REQUIRED'TTR 38 ENCL. 38

TWO NORTH NINTH STREET, ALLENTOWN, PA. 18101 PHONPr (215) 770 5151 NORMAN W. CURTIS Vice President-Engineering IL Construction-Nuclear 770 5381 April 16, 1981 Mr. Boyce H. Grier Director, Region I U. S. Nuclear Regulatory Com'mission 631 Park Avenue King of Prussia, PA 19406 SUSQUEHANNA STEAM ELECTRIC STATION INTERIM REPORT OF A'EFICIENCY RELATING TO DIESEL GENERATOR EXHAUST LINES ERs 100450/100508 FILE 840-4 PLA-656 Pear Mr. Grier:

This letter'erves to confirm information provided by telephone to NRC Region I (Mr. L. Narrow) by Mr. A. R. Sabol of PP&L on January 23, 1981.

During that conversation, Mr. Narrow was advised that the sub)ect condition was determined to be reportable under the provision of 10 CFR 50.55(e).

. The deficiency involves the. original design of the diesel generator exhaust

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lines for the Susquehanna Steam Electric Station (SSES). A description of the problem, its cause, safety implications and the corrective action taken is attached as an interim report pursuant to the provisions of 10 CFR 50.55(e).

Further i.nvestigation 'is considered necessary to determine whether the present classification of the exhaust piping as ASME Code Class 3 is still compatible in light of the revised design exhaust temperature now receipt of this information and its review and evaluation by. PPEL, the utilized.'pon Commission will be advised of our determination and of any further action deemed necessary.

P Since the details of this report provide information relevant to the reporting requirements of 10 CFR 21, this correspondence is considered to'also discharge any for'mal responsibility PPaL may. have for reporting 3.n compliance thereto.

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/i 8~ 042 z Ogpu. PENNSYLVANIA POWER IL LIGHT COMPANY

Mr. Boyce H., Grier April 16, 1981 We expect to issue a letter closing this issue during May, 1981. We trust the Commission will find this report to he satisfactory.

Very truly yours,

< N. W. Curtis Vice President-Engineering 6 Construction-Nuclear PLW:sab Attachment cc: Mr. Victor Stello (15)

. Director-Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Mr.'. McDonald, Director (1)

Office of Management Information a Program Control U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Mr. Gary Rhoads U. S. Nuclear Regulatory Commission P.O. Box 52 Shickshinny; 18655

tachment to PLA-656

SUBJECT:

'eficiency in the Original Design of the SSES Diesel Generator Exhaust Lines DESCRIPTION OF DEFICIENCY & CAUSE:

The Emergency Diesel Generator exhaust system was 'deficient in its original design.'his design,was approved, released for construction and the exhaust lines were then installed according to original design criteria. The design for the exhaust lines was, determined'o be deficient with respect to the criteria established in the Final Safety Analysis Report.and with the exhaust system requirements for the diesels procured for SSES.

FSAR Subsection 9.5.8.3,Rev. 1 dated 8/78 stated that each diesel engine< at full load, exhausts 48,000 cfm at a temperature of approximately 950 F. This data has been confirmed through information from Cooper Bessemer.

The criteria 0used by Bechtel for the design of the diesel exhaust system was based on 700 F design exhaust temperature. In May'f0 1980 Bechtel reanalyzed .

the original diesel exhaust system design for a 1000 F exhaust temperature and found that the thermal loads combined with other pipe loads would pzoduce excessive <thermal movement'of the expansion joints and excessive stresses of the equipment installed in the system. The original design of the diesel exhaust, system was determined to be inadequate.

ANALYSIS OF. SAFETY IHPLICATIONS:

The failure of the exhaust system within each of the individual diesel rooms could create an abnormal environmental condition. This condition may cause failure of diesels to continue to operate, especially when the diesel generator is being used for safe shutdown of the plant or during other modes of operation of the plant. Preliminary calculations 0 indicate0 that the room ambient temperature could reach between 266 F and 380 F. This depends on the partial/or thorough mixing and partial/complete heat transfer between supply air and,exhaust

.gases.

From Bechtel's 'analysis, the failure of an expansion joint within the diesel room could cause. the exhaust gases to enter and heat up the generator room environment.and possibly cause generator failure by high temperature.

A Cooper Bessemer representative has indicated that the diesel generator unit could malfunction if a high temperature (160 - 170 F) environment existed .

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within the diesel room.

The original design did not conform to the criteria and bases established in the Safety Analysis Report.. The original design was, however, approved and released for construction/installation. If this design were to have remained uncorrected, it could have adversely effected the safe operation'of the Susquehanna Steam Electric Station at anytime through the lifetime of the plant' PP&L has, therefore, concluded that the condition is reportable under the provisions of 10 CFR 50.55(e) ..

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Attachment to PLA-656 CORRECTZVE ACTZON:

Zn July of 1980, Bechtel issued Design Change Request (DCR) I231 to correct the above deficiency. A third exhaust expansion joint was added (two exhaust expansion joints were provided in the original design) to each of the exhaust lines to absorb the excessive thermal movement and meet excessive nqzzle loads.

Evaluation of the present classification of the exhaust piping as ASME Code Class 3 with respect to the revised design temperature is underway. Future corrective action will be based upon the results of this evaluation. Me expect to resolve this concern during May, 1981.