ML112410933

Updated LER 80-011/01X-1:on 800317,lower Crankshaft Main Thrust Bearing Found Wiped on Thrust & Journal Surfaces During Annual Insp of Standby Diesel Generator 1G-21.Caused by Startups W/Low Oil in Lube Oil Sump.Bearing Replaced

ML112410933
Person / Time
Site:	Duane Arnold
Issue date:	04/24/1981
From:	Rager M IES Utilities, (Formerly Iowa Electric Light & Power Co)
To:	NRC/OI/RGN-III/FO
Shared Package
ML112410934	List: ML112410933 ML20003G624
References
LER-80-011-01X, LER-80-11-1X, NUDOCS 8104300288
Download: ML112410933 (5)

Text

REGULATORNFORMATION DISTRIBUTION *TEM (RIDS)

ACCESSION NBR:8104300288 DOCDATE: 81/04/24 NOTARIZED: NO DOCKET #

FACIL:50-331 Duane Arnold Energy Center, Iowa Electric Light & Pow 05000331 AUTHNAME AUTHOR AFFILIATION RAGERM.S. Iowa Electric.Light & Power Co.

RECIPNAME; RECIPIENT AFFILIATION Region 3, Chicago, Office of the Director

SUBJECT:

Updated LER 80-011/O1X-lon 800317,lower crankshaft main thrust bearingfound wiped on thrust & journal surfaces during annval insp of standby diesel generator 1G-21,Coused by startups w/low oil in lube oil sump.Bearing replaced.

DISTRIBUTION CODE: A0028 COPIES RECEIVED:LTR L-ENCL 1 SIZE: - .

TITLE: Incident Reports NOTES:

RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME: LTTR ENCL ID CODE/NAME LTTR ENCL ACTION: IPPOLITOT. 04 3 3 INTERNAL: A/D COMP&STRU06 1 A/D ENV TECH 07 1 A/D MATL & QU08 1 A/D OP REACT009 1 A/D PLANT SYS1O 1 A/D RAD PROT 11 1 AID SFTY ASSE12 1 ACC EVAL BR 14 1 AEOD .3 AEOD/DMU 3 ASL8P/Ji.HARD 1 AUX SYS BR 15 1 CHEM ENG BR 16 1 CONT SYS BR 17 1 CORE PERF BR 18 1 DIRENGINEERI20 1 DIRHUM FAC $21f 1 DIRSYS INTEG22 1 EFF TR SYS BR23 1 EQUIP QUAL BR25 1 GEOSCIENCES 26b 1 I&C SYS BR 29 1 I&E 05. 1 JORDANE,/IE 1 LIC GUID BR 30, 1 MATL ENG BR 32; 1 MECH ENG BR 33; 1 NRC PDR 02 1 OR ASSESS BR 351 1 POWER SYS BR,36 1 RAD BR39 1 REACT SYS BR 40 1 FILE 014 1 REL & RISK A 41 1 VA42, 1 STRUCT ENG BR44 1 EXTERNAL: ACRS 46 16b 16 LPDR 03, 1 1 NSIC .05 1 1 MAY 0 1 iggy TOTAL NUMBER OF COPIES REQUIRED: LTTR 61 ENCL 61

0 0 Iowa Electric Light and Power Company April 24, 1981 DAEC-81-261 Mr. James G. Keppler, Director Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission - Region III 799 Roosevelt Road Glen Ellyn, IL 60137

Subject:

Licensee Event Report No.80-011 UPDATE REPORT (14 day) Previous Report Date 3-31-80 File: A-118a

Dear Mr. Keppler:

In accordance with Appendix A to Operating License DPR-49, Technical Specifications and Bases for Duane Arnold Energy Center and Regulatory Guide 10.1, please find attached a copy of the subject Licensee Event Report. (Total of 3 copies transmitted).

Very truly yours, Daniel L. Mineck Chief Engineer Duane Arnold Energy Center Docket 50-331 attachment DLM/MSR/pl cc: Director, Office of Inspection and Enforcement (40)

.U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Director, Management Information and Program Control (3)

U. S. Nuclear Regulatory Commission Washington, D. C. 20555 U. S. Nuclear Regulatory Commission c/o Document Management Branch Washington, D. C. 20555 NRC Resident Inspector - DAEC APR 2 0 met Dunne Arnoid Energy Center

• PO. BoN: 351

• Cedar Rapids, Iowa 52406

• 319/851-5611

NRC FORM 368 U. S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT DATE REPORT:

reyious Report Date 3-31-80 CONTROL BLOCK: (PLEASE PRINT OR TY ALL REQUIRED INFORMATION) 1 6 I1A 0D JA IC 11 I OLo -1ol0o0o lo.01 -ooJ (1111111110 7 a 9 LICENSEE CODE 14 is LICENSE NUMBER 25 26 LICENSE !YPE J0 57 S CON'T RE]OuT L__01_o15 10 10 1o0 3 13 1 1 0o3 1l1 1 8 1 U8 60, 61 DOCKET NUMBER 68 69 EVENT DATE 74 - 7 EPORT DATE s0 EVENT DESCRIPTION AND PROSABLE CONSEQUENCES 02 I During the annual inspection of standhy dipsPl gpnpra;tor 10 the lw I

=3 (er crankshaft main thrust bearing was found wiped on both the thrust and 04T I.ournal surfaces. Investigation revealed that the lube oil level was low. I (T ILevel was maintained in accordance with vendor manual. Redundant standby ITG I diesel 1G-31 inspection revealed similar prohlems (Se Rn W0-0123) Dipeq 0 I1 generator operahility requirements are given in T.S. 1-9-A2. Two simi .

Tl I lar RO Reports have been previously subimitted (RO 77-312 and 7R-20)I 7 8 9 80 SYSTEM CAUSE CAUSE COMP.I VALVE CODE CODE SUSCOCE COMPONENT COO SU8CoC0 SUICO0 7 8 II 9

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10 1t 12 13 FI NI NI 03:

18 UUS 19 z1l UU 20 SEQUeNTIAL OCCURRENCE REPORT REVISION LER/RO EVENT YEAR REPORT NO. co0 TYPE NO.

LB R 21 LWLI.--- 22 23 j 1101 24 26 I Ld*J 27 28 l.1.1 29 Li 30 Li- LlJ 31 32 ACTION FUTURE EFFECT SHUTOOWN ATTACHMENT NPRO-4 PRIME COMP. COMPONENT TAKEN ACTION ON PLANT METHOO NOURS 22 SUBMITTED FORM WU8. SUPPLIER -MANUFACTURER LAJ@LxJ@3 33 34 L.LJ@

35 U e 38 Ianin 10 n I 10@

37 40 4t LbaJ@

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43 I4447 cl 41 71ol@

CAUSE DESCRIPTION AND CORRECTIVE ACTIONS To IVendor Rep. indicated bearing had not failed and bearing clearances were I within spec. Vendor analysis found that start-ups with insufficient oil Iin lube oil sump resulted in bearing surfaces being wiped, Dipstick mark I 3 ings changed to Prevent recurrence, Bearing replaced. crankshaft relappe I i 1i d. gen tested sat. New invest, read due to problems found in 81 refuel.

8 80 FACILITY METHOD OF STATUS %POWER OTMGR STATUS DISCOVERY DISCOVERY DESCRIPTION 7

15 8

L.ij 9

lololol 10 12 13 NA 44 Li.jIR Annual Surveillance Test 45 46 so ACTIVITY CONTENT 12 3 RELEASE OF RELEASE AMOUNT OF ACTIVITY LOCATION OF RELEASE EI 7 8 1L.zJ 9

@ Lz.171 ID it NA I 44 46 NA ao PERSONNEL EXPOSURES NUMSER TYPE DESCRIPTION 39 l0 l 0 l 0 1z~

ZIA 7 8 9 11 12 13 80 PERSONNEL INJURIEt NUMBER DESCRIPTION 41 O 01 01 1OI NA 7 8 9 11 12 8g LOSS OF OR DAMAGE TO FACILITY TYPE DESCRIPTION 19 I z 1I- NA 7 8 9 10 80 PUBLCITY ,'\NRC USE ONLY ISSUED DESCRIPTION 7 [ N oj1(9 NA 111114111 _

7 8 9 10 8 69 80.

NAME OF PREPARER Matthew S. Rager 319-851-56110 31-8515611 PHON: - a

DUANE ARNOLD ENERGY CENTER Iowa Electric Light and Power Company LICENSEE EVENT REPORT-Supplemental Data Docket No. 050-0331 Licensee Event Update Report Date: April 24, 1981 Reportable Occurrence No: 80-011 UPDATE REPORT: Previous Report Date 3-31-80 Event Description During the annual inspection of standby diesel generator 1G-21, the lower crank shaft main bearing (#12) was found wiped.and thrust bearing (#13) was found wiped on both the journal and thrust surfaces. Further investigation revealed'that the lube oil sump level was low which likely caused insufficient bearing lubrication.

Redundant standby diesel generator 1G-31 annual inspection revealed similar problems (See RO Report 80-012). Although both diesel generators were operable at the time of the surveillance testing, extended operation, without corrective action, could have resulted in the bearing failure. Standby diesel generator operability require ments are listed in Technical Specification 3.8.A.2.. There have been two similar RO reports previously submitted (See RO 77-32 and 78-20). This unit is a Fairbanks Morse Model 3800TD 8-1/8.

Cause Description Vendor representative indicated that the diesel generator bearing had not failed and the bearing clearances were within specifications. A subsequent vendor analysis determined that engine start-ups with insufficient oil in the lube oil sump resulted in both surfaces of the bearing being wiped. The diesel generator lube oil sump level had been maintained in accordance with the manufacturer technical manual. To was preclude improper sump fill in the future, the "full" mark on the sump dipstick to relabeled "running" full and a new higher "shutdown" full level mark was added the dipstick.

Corrective Action The main (#12) bearing and thrust (#13) bearing were completely replaced, the lower half of #14 bearing was replaced, and the bearing-to-crankshaft clearance was verified to be in accordance with specifications. The #14 bearing was replaced for alignment reasons. The crankshaft was relapped and the diesel generator was reassembled and tested satisfactorily.

The lube oil sump dipstick was relabeled to clarify the "full" sump level. Oil was added to fill the sump. Operating procedure was changed to reflect the new dipstick markings.

Additional engineering investigation work is planned since a similar wiped bearing 1G-21 problem was discovered while performing the annual inspection of diesel generator during the 1981 Refueling Outage.

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