ML19281E000
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{{#Wiki_filter:, DEC 718at gg' //j>Y s \\ n e, c ~~ "EMORA"DU? F04: Carlyle "ichelson, Director g' p o e p~ Office for Analysis and Evaluation 4 of Operational Data \\ '( / FROM: natthew Chiramal N / Office for Analysis and Evaluation N', - 'i i / of Operational Data SUMECT: FCLLO':-Da E;L...,EERII ; EVtLUATID'l - DAVIS CESSE lei' 79-062 0'! AUXILIARY FErD;' ATE? SYSTEh PPESSURE SWITCi:ES The subject LER uas initially issued in 197o for an event that occurred in "ay 1979. A revision of the LEE was issued in March 1931 to include invectigation rr:sults of the event and nodifications proposed in August 1979. The lei was is;ued to report component failures in the station auxiliary feed-water (AFU' vsteri. "hile performing surveillance require"ent ucrk on Jay 21, 1979, the licensee discovered three (3) AFU systen pressure switches which would not activate and three (3) AFU suction pressure suitches which activated at pressures belou their setpoints. All these suitches were nanufactured by Static 0-Rinr, "lodel '.urbers 12V2-E4-TTLLX2 and CV2-E5-TTI4). Corrective actials af ter this event involved replaccuent of the three failed switches and recalibration of the other three. Further investir:ations after a sinilcr event on July 7,1970 (LEP #70-074/03Li, deteruined the cause of failure of these suitebes to be corrocion within the cooponent. The denineralized fe d iater, with a'nonia added fer pH control perneated through the thin Cuna-U diaphracn onto the aluninun piston causing the piston to corrode severely. A licensce f acility chance request was inplemented on Aunast 31, 1979 uhich replaced all cipht AFU suction pressure suitches with switches having stainicss steel diaphrag w and pressure norts. The use of a stainless steel diaphrarri is to preclude permeatien of fluid and subsequent corrosion a:.J oxidction of the pistons. A search of the LEPs of Davis Desse unit from August 1979 to the present revealed no further AFU syste; pressure suitch failures ubich are attributable to the sane failure nechanisa. A LE' component search involving Static 0-Ring suitches for all operatinr7 reactors was also conducted. Failures involving Static 0-Cing rodels used at Da vis Besse did not shou up at any other facility. (Only one other evcnt involvinn Static 0-Ring suitches diaphray, failure shoved up.) omcry hhCO och6 sumem o oury CF OFFICIAL RECORD COPY aa m-m m m wnu m m m t. m e.y
DEC 7 &1 Carlyle 'ichel s on tased on our revieu of the vi.rious LE"s, ac can conclude that the problen of nisapplication of Static 0-Rino diaphragn-typa switches (i.e., use of t. ' urong diaphrag naterial in fluid syste:s) was lioited to the Davis Besse unit. The corrective action taken at the Davis Cess'. Station of replacing Duna-M diaphrag: suitches with stainless steel diaphragn switches appears to be edequate. These neu switches can be included in our vatch list for future failure trends to assure the adequacy of corrective utims. Un further action regarding the nisapplication of Static 0 P.ing pressure suitches is reco: rended at this tioc. i I ( .f / atthew Chiramal Office for Analysis and Evaluation of Opc.rctional Data Att ach"en t : LER 79-Of2 cc v/attachn.cnt:
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41, -h % k t s s w a La:6 ks J 4 ? ? wk emL A rc>A nPaT-Ye* M LER SCREENING / DISPOSITION SHEET 1 Docket No. JG LER No. 7 9-(4 2 -fu i Engineer: rn W * /" /o // 1. Add'l Info. e (c c e one) If YES, describe 2. Is this event / significant? Yes No .es No Yes No (Appendix A)) (Circle one N 9,yc[k If yes, why? A _ p(e) %y F;I,,/, A D I n,,, %,o I [,m U OM A-4 %.zaac % & L d * ' ' 3. Abnormal Occurrence? (Appendix B) Yes h Yes Yes (Circle one) If yes, why? 4. Reportable to NEA? h Yes N-Yes Nr (Appendix C) Yes (Circle One) i If yes, why? 5. Recommended Action: tis Category (circle one) I II I I II IV _I III IV 6. Lead Engineer (NSSS) Disposition (Category III oh gb Lead Engineer: Category: I II IV Comments: i $tsta f ~41/uf<>. Afyx's-? }$$d- ? f6&/7 'hdb,isjp sition[k&r //Afd-$) ? /(5.V) by h vk.as.;dh A.4 Tinal Action /D 7. ' lisx ,&)J4&M+ % /n D tector( AEDD Date /
m c - l Totzoo o EDISON L81-138 March (,, 1981 FILE: RR 2 (HP-33-79-64) o-(b Docket No. 50-346
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License No. NPF-3 /,f4013 IbOI A ' 0 Mr. James C. Keppler p. H Regional Director, Region III ' u,g k g ror, Office of Inspection and Enforcement
- f U. S. Nuclear Regulatory Comission 799 Roosevelt Road
'b Clen Ellyn, Illinois 60137 -s,
Dear Mr. Keppler:
Enclosed are three copies of Licensee Event Report 79-062 including supplemental information sheets, which have been revised. The revisions to the report are indi-cated by a "1" in the left margin of each page. Please destroy your previous copies of this LER and replace with the attached revision. Yours cruly, Tq DOwg Terry D. Murray Station Superinte, dent Davis-Besse Nuc14nr Power Station TDM/ljk Enclosure cc: Mr. Victor Stello, Jr., Directer Office of Inspection and Enforcement Enc 1: 30 copies Mr. Norraan Haller, Director Office of Management Progras Analysis Encl: 3 cepics Mr. Luis Reyes NRC Resident Inspector Eccl: 1 copy 70sy6'073G - gfl 5 THE TOLEDO ED: SON CCfiPANY ED!SOfJ PLAZA 200 t/ADISO*J AVENUE TOLEDO, Otto 43552
NPL I ORM 366 U.S. NUCLE AR REGULATORY COMMISSION (7 711 LICENSEE EVENT REPORT C'ONTAOL BLOCK: l l l l l l lh (PLEASE PRINT OR TYPE ALL REDUIRED INPORMAriON) 1 6 lojtl 0l HlD lB l S l 1l@l O ! 0 l 0 l 0 l 0 l 0 l 0 l 0 l 0 l 0 l 0 l@l 4 l l li l1 l1l@l l lQ 7 8 9 LaCENSEE CQQE 14 TS UCENSE NUMBER 2h 26 LLCENSE TYPE JQ ' i7 CAI $8 CON'T " l1, @l0 l5 l0 l-j0 l3 l4 l6 @l 0 l 5 l 2 l 1l 7 l 9 Ql 0 6l 1l Si 7l 9l@ C 1 RCE 7 8 60 61 DOCKET NUMBER 68 69 EVENT DATE 74 75 REPORT C ATE 80 EVENT DESCRIPTION AND PROBABLE CONSEQUENCES h lol2l l (NP-33-79-64) On 5/21/79, the auxiliary feedwater (AW) suctir n pressure switches l o 3l l PJirlWC; fSMMeib.and P6MF3tTA were found inoperable ar.: the pressure setpoints of l o . _ ' '""'"A, IIJs681Alband ML49feh were discovered to he outside of the specified tol-l o s l erances. The station was in Mode 5 at the time of occurrence and throughout the l o 6 l corrective action. At no time would the above combinations of failures have caused l o 7 l the iuOperability of either AW trains. There was no danger to the health and safety l i of thepublic or station personnel. 1 o e SYSTE M CAUSE CAUSE COMP. VALVE CODE CODE SUSCODE COMPONENT CODE SU3 CODE SUBCOCE Icl9l lC lH l@ y@ Q@ lIl Ul S l Tl Rl Ul@ lS l@ y @ 8 9 10 11 12 13 16 19 20 SE QUE NTI A L OCCURRENCE REPORT R EVISION gp po EVENT YE AR RE PORT NO. CODE TYPE NO. O,a(gt" 7I91 1-1 1016l 2l l-l l0l3 lt l l_l l1l 28 22 23 24 26 27 28 3 30 31 32 1 E AC T ON ON PLANT MET HOUR $ $B i D FOR B. SUPPLt MANUFAC RER LAJ@LzJ@ l zl@ Lz J@ l 0 i 01010 I I Y I@ lNlg lAlg lSl3l8,;(,g 33 34 35 36 34 40 el 42 43 64 47 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS i o l Component failure and instrument drift are tne apparent causes of the inoperability. l ( Further investigation showed the cause to be the per=entinc of the fluid throuch the ! t i i 7 l diaphracm material. This alloued the corrosion of the piston. Under FCR 79-293, th2l 3 l switches were replaced with those having a stainless steel diaphrapn material. l , i 121 l I g g 80 STA 5 % POWER OTHE R 37ATUS IS Rv DISCOVERv oESCRIPTION lClh l0l0l0l@l NA l l B j@l NA l 5 ' A&,v,Tv C#1ENT Lzl@ l zl@l NA ieOu~T or ACTiv,Tv @ I ,,ELEAsEO 0,nFLEAsE LOCATION OF RELEASE l NA l i s 3 9 10 11 44 45 PERSONNE L E MPOSURES B0 NUMBER 'YPE DE SCRIP TION I d of dLzj@l NA l i 7 ,E aso~Nd',wu'iE s otsCniPTiosh NuveE n 1 d o l o l@! NA l i 9 9 11 12 LC55 OF 04 OAVAGE TO F ACILITY ' 80 T VPE DE SC HaPisON L,;J@l NA I i + e ,0 a PUB L ICs T Y , ssp (p DE $C RtP TION NRC USE ONLY - l -j l N lhl NA l llllllllIIIIII r4 - 8~10 31~ 6 0 MP R 79-077 u,.E [rntPAntn Jan Stotr pygygybN4N, Ed-M {
TOLEDO EDISON COMPANY DAVIS-BESSE NUC1J.AR POWER STATION UNIT ONE SUPPLEMENTAL INFORP.ATION FOR LER NP-33-79-64 DATE OF EVENT: May 21, 1979 FACILITY: Davis-l' esse Unit 1 IDENTIFICATION OF OCCURRENCE: Failure of Auxiliary Feedwater (AFW) Suction Pres-sure Switches Conditions Prior to Occurrence: The unit was in Mode 5, with Power (MWT) = 0, and Load (Gross MWE) = 0. Description of Occurrence: During performance of Maintenance Work Order IC-269-79 on May 21, 1979 to satisfy surveillance require =ents of Technical Specification 4.7.1.2.d, it was discovered that the Auxiliary Feedwater (AFW) suction pressure switches PSL-107C, PSL-492SB, and PSL-49304 would not actuate to their desired positions. In addition, during performance of this same maintenance work order, it was discovered that the AFW suction pressete switches PSL-4929A, PSL-4929B, and PSL-493LA would actuate at a pressure bi.cw the specified tolerances. Specific information on each pressure switch is previoed on the attached tabulation. All of the switches were matafactured by Static-O-Ring, model numbers 12V2-E4-TTLLX3 and 6V2-ES-TTX4. The station was in Mode 5 at the time of the occurrence and throughout the correc-tive action. This incident Is being reported as documentation of a component failure. Designation of Apparent Cause of Occurrence: The cause of the occurrence is component f ailure possibly due to vibration of the pressure switches. The three switches which would not actuate, even with 0 psig applied, were re=oved and a bench calibration was a t t emp t ed. Although the switches could be adjusted to the required setpoint, subse-quent calibration checks indicated that the actuation setpoint could not be repeated. The setpoints of the remaining three fciled switches had drif ted outside of the speci-fled tolerance. Further investigation after a similar event on July 7, 1979 determined the cause to be the pe r=cating of the feedwater fluid (demineralized water with ammonia added for pH 1 contt ol) through the thin BunaN diaphragm onto the aluminum piston causing the pisten to (,rrode severely. Thisrequiredachangetoastaine[hssteeldiaphragmmaterial. Analysis of Occurrence: There was no danger to the health and safety of the public or to station personnel. PCL-107C, AFFT #2 Steam Inlet is one of four such switches. The logic behind their actuation is two out of four, and with this switch inoperable, the logic would not have been rendered inoperable. Of the remaining five defective switches, two were associated with AFP #1 suction pressure, and three were associated with AFP #2 suction pressure. On AFP #1, PSL-4928A&B =casure "before strainer suction pressure" and PSL-4930A&B measure "af ter strainer suction pressure". On PSL-4930A&B the logic is such that either the "A" or "B" switch will provide the -= LER #79-062 g
'IOLEDO EDISON COMPANY DAVlS-BESSE NUCLEAR POWER STATION UNIT ONE PAGE 2 SUPPLEMENTAL INFORMATION FOR LER NP-33-79-64 intended safety function. Since PSL-493GB actuated wir.hin the specified tol-erance, the equipment would have operated as required. On AFP #2, PSL-4929A&B measure "before strainer suction pressure" and PSL-4931A&B measure "af ter strainer suction pr essure". In the case of PSL 4931A&B switches, the "B" switch actuated within its specified tolerance; therefore, the equipment would have per-formed the intended safety function. The "before strainer suction" pressure switches PSL-4929A&B both did actuate, however, PSL-4129A actuated at 2.47 psig instead of the minimum allowed 2.8 psig and PSL-4929B set.:ated at 1.55 psig instead of the minimum allowed 2.8 psig. Therefore, AFP l-1 operation could have been af fected by the defective pressure switches. AFP 1-2 would have operated properly except if the normal condensate tank supply to the AFW Pump l-2 had failed, the automati. transfer to the service water supply would have transferred at 1.55 psig instead of the minimum allowed 2.8 psig. AFP l-2 woul6 have provided the required supply of feedwater to the steam genera-tors if the normal supply of condensate had f ailed. Also, the monthly performance of ST 5071.01, "AW Monthly Test",when the unit was in operation, verified that both AFP suctions were automatically transferred upon a loss of normal condensate supply. Corrcctive Action: On May 22,1979, PSL-4929A, PSL-4929B, and PSL-4931A were ~ recalibrated to within tolerance under Maintenance Work Order IC-269-79. The remaining three presst.re switches PSL-4930A, PSL-4928B., and PSL-107C vere replaced under Maintenance Work Order IC-272-79. Surveillance Test ST 5071.01, " Auxiliary Feedwater Monthly Test" will be performed to prove operability of the pressure switches prior to the unit startup. Pacility Change Request 79-293 was impicmented on August 31, 1979 which replace 4 eight auxiliary feedwater pump suction pressure switches with switches that have .tainless steel diaphragms and pressure ports. This precluded the permeation of the In pressure sensing diaphragm and subsequent corrosion / oxidation of the pistons. addition, Maintenance Instruction 11-011 was written to delineate the method used the microswir.ch overtravel has not shifted both on new switches (bench to ensure that calibration) and installed switches. This is There have been no previously reported similar occurrences. Failure Data: time the calibration check has been perforr ed since the setpoints on these the first switches were established. LER #79-062 r-e
1 1 "3 8 ' k$p. 11RiEDIATE AS LEFT SWITCH NAME NUMBER DESIRED SETPOINT AS FOUND READING CORRECTIVE ACTION READING yg n5m AFFT #2 Inlet PSL-107C 9.0 1 1.0 psig would not actuate replaced 9.01 psig ag5 Steam Press:re (decreasing) with 0 psig switch (decreasing) pMg applied ,y2 5OOk o Al? #1 Before PSL-4928B 3.3 1 0.5 psig would not actuate repiaced 3.29 psig Straitier Suction (decreasing) with 0 psig su!tch (decreasing) h$ Pt;ssure applied dN4 o?*N m AFP #1 Af ter PSL-4930A 1.0 1 0.5 psig would no t actuate replaced 1.00 psig gy Strainer Suction (decreasing) dith 0 psig switch (decreasing) Pressure applied hg z kC iz AFP #2 Befoce PSL-4929A 3.3 1 0.5 psig 2.47 psig recalibrated 3.33 peig uy Strainer Suction (decreasit.3) (decreasing) switch (decreasing) La Pressste yy AFP 0'2 Before PSL-4929B 3.3 1 0.5 psig 1.55 psig recalibrated 3.19 psig Strainer Suction (decreasing) (decreasing) switch (decreasing) Pressure AFP #2 After PSL-4931A 1.0 1 0.5 psig would not actuate recalibrated 0.95 psig Strainer Suction-(decreasing) with 0 psig switch (decreasing) Pressure applied e
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