ML18087A910
| ML18087A910 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 04/07/1983 |
| From: | Toman G FRANKLIN INSTITUTE |
| To: | Shemanski P NRC |
| Shared Package | |
| ML18087A907 | List: |
| References | |
| CON-NRC-03-81-130, CON-NRC-3-81-130 TAC-49795, NUDOCS 8305170106 | |
| Download: ML18087A910 (84) | |
Text
{{#Wiki_filter:*. / APPENDIX B
\ INTERIM TECHNICAL EVALUATION REPORT EVALUATION OF FAILURE TO TRfP
*OF REACTOR TRIP CIRCUIT BREAKERS ON FEBRUARY 2i AND 25J 1983 SALEM NUCLEAR GENERATING STATION UNIT 1 NRCCOCJCETNO. 50-272 FRC PROJECT C508 NRCTACNO. 49795 FRC ASSIGNMENT "O" NRC CONTRACT NO. NRC-03.a1-130
.Prepared t:Jy Franklin Research Canter Author: G. J. Toman 20th and Raes Streets Pl'llladatphia. PA 19103 FnC Group Leader: G. J. Toman Prepared for Nuclear Regulatory Commission Lsad NRC e..,gineer: l?. Shemansk:f.
Washington. O.C. 20555 April 7, 1983 This report was prepared as an account of wonc sponsored by an agency ot the United States Government Neitner the United States Government nor any agency thereof. or any of their employees. makes any warranty, expressed or Implied. or assumes any legal liability or responsibility for any third party's use, ortne results of sucn use, ofany lntcrmatlon, aQpa-ratus, product or precess dlsclcsed In this report, or represent3 that las use by such third party would not Infringe privately owned rtgnts. Prepared by~ ,,/ Reviewed by: *
- Apprcvee by: _
. ~...,___,-~d-R'f __..i?'t:-tl~y Project: Manager Oepartment Director ( A e. .J.t*~ 1)
Date: i=/7 I IJ~* Cate: 4/7/~
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- FORmORD This Tedlnical Evaluation ,Report was prepared ~y Franklin Research Center under a contract with the cr.s. NUclear Eegulatory commission (Office of Nuclear Reactor Regulation, Division of Operating Reactors) for technical assistance in support of NIC operating reactor licer1sing actions. 'l'he technical evaluation was conducted in ac:::crdance with criteria established by the NRC.
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INTBODtX:TION This Interim Technical Evaluation Report contains a compendium of the reports issued by .Franklin Research Center (FRC). to the ~uclear Regulatory Commission (NRC) and updates to April 6, l.983, FRC's findinqs concerning the failure of the Salem Unit l Westinghouse OB-50 reactor trip circuit breakers on February 22 and 25, l.983. 'l1le evaluation centered upon the. undervoltage trip attachments of the circuit breakers which were supposed to trip the circuit breakers when deenergized. This is a report on work in pro9ress1 thus, the conclusions contained herein may change as new information from the proposed Licensee verification testing becomes available and subsequent evaluation is completed. Table l lists the reports and letters transmitted to Mr. v. Noonan, C!lief, NRC E:ruipment Qualification Branch, prior to April 6, 1983. O!RONCLOGY OF E"lAI.UAT!ON
/
~. G. Toma."'l of FRC accompanied Messrs. V. Noonan and ::>. She.'Uanski of NEC Equipment Qualification Branc.'l and Mr. J. Beard of NRC Operating Reactors Assessment Branch to Salem Nuclear Generating Station (Salem NGS) on Marc.~ 3,
.!.983. The purpose of the trip was to gather information concerning the 5alem anit l events of February 22 and 25, 1983. The information obtained is contained in Appendix A. Appendix A also contains a discussion of initial findings concerning the undervoltage trip attachment (UVTA) that did not operate ~roperly. Failure of the CVTA to operate prevented the reactor* trip circuit breakers (RrCB) from opening automatically. Figure l contains photographs of the *as-C'eceived* state of the onit 2 *B* IJVTA supplied to FRC by ?ubJ.ic service Electric and Gas Company (PSE&G). on March 3, 1983. on page 3 of Appendix A, the second paragraph states that Chemical Rubber Company CRC-2-26 lubricant was used on the OVTAs associated with Unit l. on March 18, 1983, during a meeting with the NPC, Westinghouse personnel stated that the Westinghouse technician's report states that only one RrCB was worked _upon at the Salem plant on January l3, 1983 and that the lubricant used was Calfonex 78A. FRC has been unable to find a supplier for this lubricant.
~n~in Rese~n:h
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Appendix B contains the review of Revision l of Sa1em NCS Maintenance Procedure M3Q-2. Since tb.e reyiew, Bevisicn 2 has bl!i!p issued. Revision 2 requires ten successful t:ippings of the RrC:S by a new OVTA prier to returning the circuit breaker to use when the OVTA is replaced. The procedure is titled
*Reactor Trip and Bypass ACB Semi-Annual Inspection and Testing*; the title now states the periodicity of testi119. Cautions concernill9 handling of the lJVTA and further tests of the RrCB and tJVTA were added in Bevision 2.
Appendix C describes the *as-received* electrical testing of the onit 2 *s* OVTA. * 'l"he device was found to operate at 26% of normal voltage ratb.er than between 30 and 60% of normal voltage as stated in the manufacturer's literature. 'l"he evaluation of the device during these initial-tests indicated tb.at the device should be compared to the other tlVTAs available at t.."le Salem plant_to determine visible variations f:om device to device. On March 10, 1983, ~.essrs. G. Teman and R. Cranisky o_f F~ went to Salem NGS for the purpose of comparing the oni t 2 *:s* OVTA to the remaining Oni t l OVTAs. Upon arr::.val at the Salem plant, it was found that onl.y one C'rlA *11as available. Comparison showed variations in manufacture and reset lever adj:Jstment spring setting between the two de*1ices. Messrs. Toma."1 and Cranisky also observed operation of a t:ni t 2 RrCB with the 2 *:s* !'NTA. When t:le OV'l'A was attached to the circuit breaker, power was not applied to the CVTA. T!lerefore, when the RrCB was closed, the CVTA reset iever was held back manually to prevent a trip-free opening of t!le circuit breaker. The UVTA
- eset lever was t.~en released. 'l'he' UVTA latch released and the trip lever
- noved up to tbe trip bar, but the Rl'CB did net trip. A second attempt also resulted in.no trip. 'l'WO mere attempts at manual operation cf the tNTA did t:ip the Rl'CB as did.subsequent electrical operations.
Appendix D contains the letters of transmittal for :ni.c:oscopic ~cto
'.*. :~ graphs cf the latch, latch pin, and latch spring from the Onit 2 *B" CVTA shcwingrougbness and wear on the mating surfaces.
. . .1 Appendix E contains the FlC findings from the beqinn_ing of the evaluation up to ~..arch 21, 1983. It discusses.two possible failure modes for the OVTA and findinqs from a March 17, 1983 trip to Salem.
.* .* U~U 1 Franklin Research Center
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. Appendix F is *a trip report from a Marcil Jl, l.983 visit to Salem to eval.uate testinq.perfcrmed by PSE:~ on the t:Init l Rt'C:Bs ..
E"INDINGS The following- is a summary of the significant findings of the evaluation to date:
- l. Manufacturing variations existed on the original. OVTAs supplied to
. the Sa1em plant.
- 2. Manufacturing variations exist on the four new tJVTAs supplied to Sal.em Otii t l.
- 3. No lubrication of the OY'I'As appeared to nave been performed from the time of manufacture (appcaxima.tely 1972) until January l.983 when a lubricant otb.er than that reeommended by the manufacturer was used.
- 4. The Chit* 2 *13* TJV'l'A had its reset lever arm spri119 adjustme."lt dlanged some-time after instal.laticn, possibly to remedy inadvertent openings of the circuit breaker during operation or while attempting to close the circuit breaker prior to operation.
- 5. Improper adjustment of the OV'l'A reset lever arm can increase the probability of an inadvertent opening of the circuit breaker (trip free) if the arm is. set to overtravel too far.
- 6. Loosening of the reset lever arm spring reduces the tendency to trip
. f~ee, but also reduces the force that woul.d *cause the OV'l'A to unl.atcb when deenergized.
- 1. variations in reactor trip bar forces exist among the Salem Unit l
~CBs.
- 8. 'ttle mating surfaces of the Unit 2 *B* latch components are rough and appear not to have been honed. Adc:!iti*onal. wear from operation appears to be significant.
- 9. Hesitation in lever arm motion when the OV'l'A is slowly deenerqized was noted in the unit 2 *a* UVTA and the device. operated bel.ow the expected 30% of nominal. voltage point.
lO *. on Marcil 18, l.9~3, Westinghouse switchgear Division personnel al.so indicated that the CVTA must be replaced some time during th~ life of the plant. Criteria fer determining when to replace the OVTA do not appear to be available. ,
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CON:I.USIONS It is believed that in ~e as-manufactured *new* condition, the l983 UV'l'A will. properly trip a circuit breaker that has a trip bar force requirement within the manufacturin~ limit of 31 ounces, and would probably consistently trip a circult breaker with an- as-found trip bar force r.equirement of up to 38 ounces (the force required to trip the unit l "A* RrCB). sowever,*sufficient evidence has not been presented to show that current manufacturing processes for the UVTA, when coupled with maintenance, will eliminate long-term failures that appear to be mechanical, age-related phenomena. The variations from device to device cause concern. 'ttle fact that honing of latch surfaces is a hand operation indicates.that variations in the surfaces of the latch will remain even though no extreme roughness should be expected. In addition, the lack of quantitative acceptance criteria for the OV'l'A adds concern that impending failures might be missed during inspection and maintenance. RECOMMENDATIONS
- l. Acceptance criteria be set for parameters affecting correct operation of the O'VTA.
- 2. Testing :nethodology for acceptance*tests be prepared for factory and Licensee use.
- 3. uniformity of construction be instituted or suf;icient testing be performed showing that the variations in the devices are of no consequence to reliable operation.
- 4. Life testing of the UV'l'A be performed to show that the device can successfully operate for the intended lifetime with proper maintenance.
s*. Criteria be developed to determine a replacement interval for the UV'rA such that replacement occurs significantly before end-of-life failure.
~nkli~ Research Center
. A OMlian cl"The Franie!in ._,..
s.* '!he base.line testing of OVTA output forces and RrCB trip bar trip forces is a f.irst step in proving the adequacy of the OVTAs for
- continued use. 'lhese test resu.lts sbou.ld be compared with results taken periodically during the life of the tJVTAs. In order to allow preventative action to be ta.ken, trending of the variati'ons in the
- results should be performed to determine if degradation in OVTA and
~CB performance is occurring.
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Tabl.e l..
- Chronologic:a.l Li.st of Beports and Correspondence from Fg: to the NR: concerning Failures of Reactor Trip Circuit Breakers at Saiem unit l on February 23 and 25, 1983 APoendix Date/Subject A March 4, 1983 Initial Report on the salem Onit 2 Onder~oltage Trip Onit B March 9, 1983 Reviews of Proposed Corrective Action by PSE&G and of Maintenance Procedure M3Q-2 c March 9, 1983 Report of Initial Testing of the Salem Onit 2 *B*
Ondervoltage Trip Attachment D Marcil 21, 1983 Photographs of the Salem Unit 2 "B" Undervoltage Trip Attachment (Transmittal letter and description of views only) E March 22, 1983 Salem Events of February 22 and* 25, 19831 Failures of
- P.eactor Trip Circuit Breakers1 Final Report of Initial Investigation March 31, 1983 Trip Report: Salem Unit l Reactor Circuit Breakers (Transmitted to the NBC for the first time **as part of this Interim Report)
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A. ondervolta9e ':rip Attadmlent B. Oftdervoltage Trip Attadm:ent
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- c. tlndervoltage Trip Attachment. c. ondervoltac;e Trip Attacbmen.t Side View Side View Pigu:re l. onit 2 *B* tl'ndervoltage Trip Attachment (A, c, and o a:e pbotcgrapis of the as-received _aonditicn*.)
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INITIAL REPORT ON THE SALEM UNIT 2 UNDERVOLTAGE TRIP UNIT APPENDIX A
~nklin Resea~ch Center A Division of The Franklin Institute The Ben,.min Franklin Pa~. Phila~ Pa. 19103 (21~) 448-1000
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~nklin Research Center
- A Division "of The Fnnkiln Ir.stttute March 4, 1983*
~. Vincent Noonan Chief, Equipment Qualification Branch U.S. Nuclear Regulatory Commission Pnillips Building, MS-P-234/RM P-234D 7920 Norfolk Avenue 3echesda, MD 20014
Dear Mr. Noonan:
Attached is the initial repo~ an the Salem Unit 2 under-voltage trip unit. ! have detailed same possible causes and i:idicatad the initial tests and evaluations to be per!or:ed. Also attached is a request for additional equipment from PSE&G to be used ill the investigation. Should the;re be any questions, please call me a't 215/4.i.8-1257. I intend to begin the tests on Monday, March 7, 1983. GJT/ih Encl *
- 10th&: Rao:e Streets. Ph~ladelphia. Pa. 19103 (215) 448-1000 Ji***-=*~-.****°'!'***.*
TWX-710 670 1889 I **
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st!MMAll AND I'N'ITIAL- FINDINGS Initial inspection of the cnit .2, B Wlder-voltage tl:ip unit indicates a possillility of multiple cont:ibuting causes of failure. Possible contributors are tl) lack of lW::>rication: (2) wear; (3) 1%1Qre frequen~ operation than intended by desisn:. (4) corr~sion from improper lubrication in January, 1983: and (5) nicking of latdl surfaces caused by vibration f:om repeated operation of the breaker. ~e c~ntr ibutors appear "tc be cumulative with no one main cause. 'n:le initial investiqation does indicate that the failure is aqe related and that a new device woul~ perfoca properly. Many surfaces of the latdl :nec:hanism ue worn and the additional. friction tends to prevent proper
. operation. Proper llJ.bdcaticn througilcat the life of* the device may have .
prevented the weu that c:an be seen on the sample *
. -* . ~e tests and examinations E'IIC proposes to perform will. attempt to det~r::ine the cawae of failure and if possible reproduce it. '!:le followinq summarizes the initial findinqs and lists the pro?lsed tests.
OISCCSSIOR OP' C!~STAte?:S
- l. !nitial thcuc:hts fro1u information received crier to Marcll 3, 1983 visit to Salem aeneratina station.
?rem infcr:uation received by J;ilcne and by telec=pier, 'fil'f initial bel.ief prior to visitin; ~e site was that the under-'lcltage t:ip device did cot operate because it had "not been exercised very frequently, my be.lief being that dust or dir*.: acCUmul.ation on the device in two months time prevented its operation.
- 2. Initial. eval.uaticn of information received at Salem site on March 3.
When I arrived at the Salem site, I met vit:h Vince Neenan, Paal. Shemanski, and J. T. Beard, al.l of the HBC. we were given a walk-around inspecticn of the plant by an oper.ator named Ray McCarthy. We inspected the onit 2 Reac1:cr T:ip c:i~i~ breaker area and visaal.ly examined the circuit breakers which were laying on the fleer near their cabi_cles. 'l'he unde.c-Yoltage trip devices were remcved frcm eac::i of these circuit breakers.
'l'!le shunt t:ip coils were in place. 'l.'he cucuit breaker trip bar moved freely. We then went to the cnit l Reactor Trip circuit breaker area. 'Ihese breakers had been removed and brougilt to the electrical maintenance area. It was noted* that an inverter wnidl was approximately 4 ft f:cm the circuit-
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I breaker ccmpart:nent was blowing hot ai: into the ream, and into the circuit ( :-": l:lreaker compartments, and that the 9eneral area tempera~re was well above 80 *. We then were taken to the elect:ical maintenance area, where we interviewed Mr. Keteum, an electrical maintenance supervisor, who discussed the circumstances of the removal of the circuit breakers that were involved with the incident on cnit l. We were also introduced. to Hr. Leo :Roland, ancthe= electrical supervisor, who bad aJ.so worked on the circuit breakers* in
.question in AUgust of l.982. 'l:he information received was that the circuit breakers and their under-.,oltage trip device had been operated frequently and had operated within a few days prior to the incident. '!'bis dispelled my i."l.itial concern that the .devices llad net been exercised often eneugh.
I requested that Salem management provide one of the under-voltage t:ip devices, and a shunt trip coil, for testing at Franklin Researd:l Center. ~ey did so. It appears that new under-voltage trip coils are not readily available.* 'l!'!is*wiJ.l be investigated at a later date. P-ESUL'l'S Ol!' INITIAL EX>>!INA'!'!ON; SOME l?OSSI:3LE CAC~S Since receipt of the under-voltage device, whidl is the cnit 2 a trip under-'loltage device, I have noted rougi:ness in the operation ~ the trip late. '!'here is some drac;gi."l.g of the mechanism, and portions of t."le latch mechanism have obvious signs of wear. POssibla c:ont:ibuting factors to the failure to operate are a lack of lubrication, wear, jarring of the under-voltage device f:cm the <;ircuit breaker operation and more frequent operation of the under-voltage trip device than was intended during design. My belief is that under most' industrial applications, ~e under-'loltage device would be used very infrequentl.y, and probably would onl.y be operated durinc; test sequences at per~aps yearly or longer intervals. '!herefoz:e in industrial applications, the device would operate onl.y a few times, perhaps 20 or 30 during its lifetime, and would not be a normal tripping mechanism for the breaker. However, in its use at Salem, it is the prime trippinc; device fer the circuit breaker, and as such is called upon to operate on the order of 50 tim~s per year. 'ttlat would mean, at its current age, in l983 th!!re ....ould be possibly 400 to 500 trip operations on this device. curing t."le investigation, it was noted that the shunt trip coil has been operated since' August, l982 once every 7 days rather than at longer intervals. .'ttlis means that t."le circuit breaker is now tripped and closed
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!. every 7 days, causing_ :he jarring of .the entire lDl!ehanism of the circuit breaker. This may er .may not be significant in that t:ie breaker and its attached relays and coils dr.ie to the 1lOntal. oceraticn " under-v~ltage would stay energized during these trippings and its latch mechanism would be of the re.lay jarred somewhat by operation of the breaker. ~is coul.d possibly add to the friction which is building up in tne latch medlani.sm from nor:nal .operation by caL1sing the latc:::i medlanism to just slightly nick the surface that it rides on thereby tending to prevent operation. PUrther investigation will t.ry to determi.:ie whether this ~ indeed a ccnt.ributcr tc t:le mis-operation. It woul.d appear from initial inspection of the device that wear and roughness of matin9 surfaces in the t::ip latdl are ccnuibuting causes. Proper J.u.bric:aticn may have prevented the current situation o:r c:cul.d reduce this roughness to the point where proper opera t.ion c:oul.d oc::w:. F:c will at:empt tc de-cl!l:mine whet.her the .OC-2-26 lu.bricating, cleaner spray added to t:le problem by ei tiler causing corrosion or removing al..l
- 'S!Sidual lubrication £rem initial. c:cnstruction. It appears cat from t'le time of initial const:uction of the under-'Toltage trip units, up until J'anuaey of lS83, no lubrication whatsoever had been performedr and then in January of lS83, lubrication was performed by the maintenance personnel in conjunction wit."l a Westinghouse tedlnician. i\t this tUE!, ~-2-25 lubricant cleaner was sprayed on a..ll four trip devices associated with onit l.. 'lhi.s lW:lricant is b~ing procured by FRC for testing purposes.
LISTING OF :::XPECTED INVESTIGATION
- l. The firs*i: test will be to perform various de-energizations and energizations of the under-voltage trip unit and mcnitcr the device under various conditions.
- 2. 'nle second test will be to disassemble the latdl mechanism to observe the surfaces of the various parts of the latch, and i=botcgrapb these surfaces t.'lrough a m.ic:oscope to determine various leveJ.s of wear in these surfaces.
- 3. 'l11e tbi.=d test is to determine the effects of Cl!C-2-26 spray on the various types of metals used_ in this device. An attempt will be made to use metals ot.'ler than these in t."le actual device. If possible, we will deter:nine the c:::iemical consistency of this spray, hopefully through the manufacturer.
- 4. 'nle fourth test is only possible if the spare circuit breaker can be oi;)t.ained from Salem. '!he under-voltage trip device and. the shunt ccil.
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I I would be ~unted upon tbe breaker, and the breaJcer woW.d be _cpe:a'ted
*-.)* repeatedly to determine th~ effect ~.the *imder-volta9e t:ip unit. It is surmised that while the devic:e is ener;i=ed and the breaker t:ips and closes a number of times, aaditional fricticri of the t:ip latdi '112.Y cc:cur from the vibration. ~is test vol:ld primarily deter.tine whet!:ier such
.additional friction occurs from operation.
'l'O prove t!lat the sample under-'1'oltage trip Wlit is identical tc the Onit l devices, a visual inspection of all existing Salem Onit l and 2 wider-9oltage t:ip wiits should be perfcr:Ded* . ~is can take place at Salem. Ne disassembly is needed. The devices can be mcunted on the 0 ~s or lcose. ~is sbould be dcne as* soon as possible. '!.'Uesday March a, l.9 83 is rect1mmended.
?urther tests will be deteained upon the basis of these initial tests. All.
tests will be ncn-dest:uctive tests sudl that the devic**wil.l. be* aeie tQ be 1.2sed fer further testinq and possible return. to the 11tility. AD'CI'l'IONAL f!EQUESTS FOR SALm ~Tr.JG STATION !9.N1\GF.MENT
- l. For use in investigaticc. of d:le incident, Fli: requests that t!le spare DB-50 circuit breaJcer be made available fer ase at !'BC for a period of 2 weeks. Delivery is requested as seen as practical. SOpefuJ.ly no later t!lan March 9, l9 83.
- 2. n:lC woulc like to v.isually inspect all of the remaininq widervoltaqe t:ip devices frcm sa.lem l and 2r includinq these at t:le NB: Headquarters. It would be beneficial to have t!lese ali in one place to speed the review.
'.there would be no ciisassembly and the devices o;,ulci be on the circuit breakers fer this. inspection. It is hoped. that this could be done on *
'l'llesday Marcil 8, 1983.
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ll REVIEWS OF PROPOSED CORRECTIVE ACTIONS BY PSE&G
... AND OF MAINTENANCE PROCEDURE M3Q-2 APPENDIX B "ftnklin R~search Center A Division of The Frankiin Institute The Senjarrun Franldin Parnay, Ptlit... P11. 19103 (215) 448-1000
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-Qnkl~ Research Center A Division 9i The Frankli."'l Instmtte
~arch 9, 1983 Mr. Vincent Noonan Chief, Equipment QUalification Branch Il.S. Nuclear Regulatory Commission Phillips Building, MS-P-234/R..'! P-234D 7920 Nerf elk Avenue Bethesda, ~ 20014
Dear 2'4..r. Noouan:
Attached are the reviews of the proposed corrective action by Public.Service Elec~ric & Gas Co. of Ne..- Jersey as detailed in the letter from Mr. Richard A. Underlitz to Mr. D. G. Eisenhut dated ~..arcll 1, 1983, and of Maintenance Procedure M3Q-2. These documents ..-ere previously trans-mitted to you on March 9, 1983, at approxil:lately 11: 00 am, by telecopy. Very truly yours,
- I Y-i~ ****~
- Gary µ. ;oman Sectib Leader, Qualification Analysis and Planning Section, Nuclear Engineering Dept.
GJT/:!.b F.ncl.' cc: M. Carrington P. Shemanski 20th & Race Streets. Philadelphia. Pa. 19103 (21SJ ~8-1000 TWX-ilO 670 1889
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RmI:::W -OF LE'!TER FROM MR. RICB'.ARD A. O?mERLI'rZ, VICE PRESIDENT NOCLEAR, PSE&G CO. . ', TO MR. D. G. EISENHUT, DIRECTOR, DIVISION OF' LICENSING, NRC, DATED MA..~R l, l983.
Subject:
Reactor Trip Breaker .Failure, NO. l tlnit, salem Generating Station, Docket No. 50-272.
'I'he following are resul.ts "of the review of the referenced letter. This review is restricted to statement~ concerning the "shunt trip* and "under-voltage trip* attadlments of the Reactor Trip Breakers.
Page l of t:h_e letter states that the sole reason for the failure_ of tbe undervoltage trip attadlment is laclc cf proper lubrication. FBC continues. ta evaluate this possibility and makes no finaJ. determination at tnis time. nc is also evaJ.uating other possible related conditions such as, .improper appJ.i-cation o:f the* device, dust and debris in the moving coiJ. section of the device, b incling of the late pi.n, and residuaJ. magnetism 'in the ccre. ::'P.C' s findings will. be forwarded ta the NEC on or. before April l, l98J. *
-~ has no comments on Page 2 of the letter.
. I On Page 3 , in Item 2, a new maintenance procedure MJQ-2 is described.
However, no periodicity for maintenance and no other method of invoking tnis p:ocedure are stated. (Nc1:e: tne M3Q-2 procedure al.so does not contain this information.) Since laclc of mairJtenanc:e is indicated by PSE&G co_. and Westinghouse as the probable cause, the* periodicity for maintenance must be addressed. On i'age 4, Item 7 describes new testing cf the Reactor Trip Breaker. One test requires timing of the circui~ breaker operation when tripped by the undervoltage trip attadlment. PRC recommends that this test be performed 3 times and that t:!le average time be compared to previous tests (as test data accumulates) * '!:his wouJ.d provide a means of determining variations in .the trip attachment and circuit breaker response. Inc:easin9 time lag woul.d be indicative of an impending problem. On Paqe 4, Item 10, FEC agrees that mcving tne undervolt:age trip attac:b-ments from one circuit breaker to another is inadvisable and aqrees with the Licensee's proposed action. On ~ages, the Licensee does not define whether the shunt trip is safety related or not. Since tnis device proved to be hiqhl.y important when tbe undervoltage trip attachment did not work, it wouJ.d se~ very important ta
- consider the shunt trip as safety-related. In addition, the shunt trip is in series with the circuit breaker auxiliary switch tbereby requiring the auxi-liary switch to be safety related.
Prepared by G. J. Toman 3/8/83.
~nkJin Researdt Center
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REVIEW' Ol!' PSE&G CO. PRcx::EJJU'R!: M3Q-2, ..
- TITLE: ~TOR TRIP ANO B'l'P11SS ACS INSPECTION ANO ~ST. REV. l. 3/4/83.
'ttle copy of this procedure received by FBC contained an additional one page document laeelleq .*salem NUclear Generating Station, Reactor Switchgear, \
Operational Verification Program.*
':.nc has the followiiiq comment on the Operational Verification Program.
Item 2 states that ~3-2 requires 10, 40, then 50 trips of the circuit breaker depending upon the number O*f failures Of the unde.rvoltaqe trip attachment *.
?iQ3-2 does not contain sudi a requirement. Allowinq any failures durinq testing is wholly inappropriate for the unde.rvoltaqe t:ip unit and maintenance procedure M;23-2 should not be modified* to allow the undervo.ltage trip attadiment to fail, no matter how many successful operations follow.
Failure to operate once during a sequence of trippings of the attachment indicates severe prob.lems in the mechanism and places the reliability of its function in doubt. Item 2 of the document al.so states that the lO, 40, then SO trip test system is statistically sound for the application. '!his is in-correct for the application. AS ciesc::ibed~ the test method would allow 2 failures in 100 tests. '!his would be a 0 .02 probability of failure. The.re are two reactor trip circuit breakers in series. ASswning independence of failures (i.e., no common mode mechanism) the probaeilit-/ of s:i:nu.ltaneous fa:l.lure of the t'WO. circuit breakers would be a .02 x a .02 or o .0004. i:ttiis in-dicates that a failure of both reactor protection systems would occur once every 2500 trips. For Sa.lem tlr1it l, whic:n is said to have so. trips per year, a fa.llu.re to. trip would occur at least once per SO years. 'ttle allowance of any failures to t:ip dw:inq testing is totally unac::eptable. Re~iew of M3Q=2
- l. NO statement of the period between maintenances is made. NO method of in-voking this procedure is given.
- 2. Page .lO of 23, Item 9.7.2.2 indicates that lubrication could de some good, but does not indicate bow to determine when to lubricate the undervoltaqe trip attacment. Fm: has found that the onit 2. t:ip attachment trip lever hesitates when depressed. It is suqgested that maintenance perscnne.l slcw.ly depress and release the t:ip lever to determine if it binds du.ring
. operation. If it does hesitate or bind, and lubrication does not remove this bindinq, replacement sbou.ld be performed. Also, the p.rocedw:e sbou.ld indicate. a required interval between lubrication. 'Ibe Manufacturer's
'rechnical Balletin, NSO *Data Letter 74-2, suggests starting with a 6 month interval between lubrie<ition~
':ttie second parag.ra¢ of Item 9.7.2.2 indicates the portions of tbe under-voltage trip attacment to be lubricated; however, no mention is made of the latch to latch spring (the copper alloy flat sprinq) surface, the bearinq points of the latch spring pin, and the bea.rinq points of the reset lever a.rm.* All of these, especially the latch to latch spring sur-face, are friction sources that c:ou.ld prevent correct operation and should
*.._*! be considered for lu.b.rieation.
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- 3. Section 9 .8 d_isc:usses timing of. the* circuit breaker wl:\en t:ipped by the undervcltage trip att.aennent. ~ suqgests that th.ree timing tests be performed and tne average ti:e be c:cmpared tc previous tests as successive tests are perfoced. '!!lis woulci allow degradation in performance tc be determined.
Note: If the trip times are known to be consistently near tile trip limit \ of 4 c:yc:les, trending of tile trip times would not be usefu.l. However; if a new breaker starts witil lower trip times such as 2 cyc.les, trending could be indicative of cieg:radation.
- 4. Enclosure l of M3Q-2 was taken from the Westinghouse Low Vo.ltage Meta.l Enc.losed switchgear Manual. 'this diagram incorr~tly shows attachments suc::b as tile overcurrent trip device tilat are not used in tile reactor trip cirC'.iit breakers and does not show tile sb.unt trip or Wldervoltaqe_ trip attachments. FBC suggests tilat an applicab~e diagram be included in the procedure.
- 5. In accordance with 3 above, PEC suggests that Enclosure 7 be modified for tilree timings of t!:ie circ:iit breake: racer t:ian one.
Prepared by G. J. 'l'Oman 3/8/83 *
~nkfin Research Cen~
A Diw- cl The FTWllllln .,_...
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REPORT ON INITIAL TESTING OF THE SALEM UNIT 2 "B" UNDE;RVOLTAGE TRIP ATIACHMENT APPENDIX C
~nklin Re~earch Center
.;** A Division of The Franklin Institute *
""1e Benjamin Franldin Parkway. Phil&. Pa. 19103 (21!5) 446*1000 i
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~~klin Research Center A Division of Tne F:anklin Inst:tt;tte March 9, 1983 Mr. Vincent Noonan Chief, Equipment Qualification Branch U.S. Nuclear Regulatory Commission Phil.lips Building, MS-P-234/RM P-234D 7920 Norfolk Avenue Bethesda, MD 20014
Dear M:
- r. Noonan:
The a~tacbed document describes initial tests cf the* Salem 2 B U'nde-"'"Voltage Trip attac!lment. Please note the finding on Page 2,
!te.m 3. !he as-found condition of the device iS very disturbing.
When energized and de-energi:ed the device does not operate within the specified voltage range and hesitation vas noted in the latch to lat:i:h pin operation. V~ry ~t:.r.Uy ;,ours,
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_,,,,. Toman Section Leader, Qualification Analysis and Planning Section, Nuclear Engineering Dept. GJT/ih
-eo- ,. ~CJ..
cc: M. Carrington P. Shemanski 20th & Race Streets. Philadelphia. Pa. 19103 (.215) 448-1000 T\V'X ilO 670 1889 0
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REPOµ OF INITIAI.. ~TING OF Im: SAL~ 2 "B II ut"DD.VtlI..TAGE TRI? ATT.A.~, 3/9/83 ~
- 1. Described O~eration
.a. The UnderVoltage (UV) Trip Attachment operates at 60 to 30% of nor::lal voltage per the instruction manual.
- b. Nor.:al vo_ltage on this device is 48 Vdc.
Note: The manual is describing an t.mdervbltage trip attachment ~th an ac coil designed to operate on line voltage. The device supplied for Salem has been modified by replacing the ac coil ~th a 48 Vdc coil.
- 2. As-Found Tri:ming Point ThLSalem 2 "B" lJV trip attachment consistently tripped at 12.6::0.4 Volts*
de *'-hen voltage was gradually reduced from 48 Vdc. This is 26% of nor.:ml. operai:ing voltage. It was noted that the reset ar.11 moved pari:ially to-wardS unlatching a few "1."0lts before unlatching occurred indicating binding of the la:ch to latch pin. J. The adjus~t for spring tension for the reset lever spring was found on the Salem 2 "E" UV Trip attachment to be approximately 1'1 tur.is below the surface of the locki:lg nut. The adjustment "las brought to the condition sh~ on Fig. 17 .oi the 'Westinghouse Ma.'lua.l., "!nstructions for Types DB-50, DBF-16 and DBL-50 Air Cj.rcuit Breakers," which is approxi:lately 6 tun:is beyond the surface of the locking nut:. (See attached drawing.) The 1JV trip attacbmec.t then operated at 25.8 Vdc, ....ill.ch is 54: of nor.nal voltage.
~nen tension w--as reduced to the lowest limit: (1 co l~ turns below the as-f ound conditicn) the device operated a 6.3 Vdc or 13% of voltage.
This indicates that the setting of the reset ar.:n spring tension is c~itical to corTect ooeration and that the as-found oosition of the adjustment is definitely below the desired level.
*Y
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~~~~ Fnsnklin Research Center
. AC:.-Cln..I"_,.,.__ Page 1 of 2.
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Reset Lever Spring Adjustment Screw The =Qvmg core is nor=ally held ~edally
~ains: the s-. .ticr.a:-; c:o~ to hold the ~nca:-..a rod and c:ol".sequen:iy :he reset lever. in the reset pos1con. 'w\'ben :he coil voltage is P-<11.u:ed s-.;::ic:ie!ltiy, the :'!!set lever spmg a-*e:comes :he
- !~:::'.c ar::ac:on o! the c:o~ ar.d :o:.tes the
- i!Set !eve: cioc:t*wue .*.;,s the reset le\*er rotates. it c:.a::-:es wit."! it :he !a.u:::. pin ~.ic~ ro~tas re!at:ve to t.~e lar.:h u.r.::il :."le la::.'l is re!eased. \\'"ben the l.a~!l ~leases, the :rip s-;::"--:g ?'O~tes :.~e :rip !f!ver c:::~-:tar::oc:kr.se to ::O:p the breaker. The lau:h is
~t by :.'l~ eos.s ba:. ::o~"lg :.~e adj:..LStable ~et
!.:*er a.s :.~e !:~aZ.:er :;-e~.
Page 2 of 2.
"PHOTOGRAPHS OF THE SALEM UNIT 2 "B" UNDERVOLTAGE TRIP ATTACHMENT APPENDIX D
~nklin Research Center A Division of The Franklin Institute The Benjal'nin Framdin Pa~. Phil-.. Pa. 19103 (21') 448-1000
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~-- .* ~ ~ ~ UFranklin Research Center "
A Division of The Frankl.in Insc:ute
?'.arch 21,, 1983
*. Mr. Vinc:en: Noonan Chief, Equipuienc Qua.lific:aciou Branch U.S. Nuc:l"ear Regulacory CQ:missicn Phil.lips Building, !".S-P-234/R.'! P-234'0 7920 Norfolk Avenue Bechesd.a, MD 20014 IO 3E O~ BY ADDRESSZZ ONLY
Dear ~. Noonan:
E:u:.loseci herewich a.re the pbot:ographs of the Salem Cnit 2 "3" Cndencltage Trip Ac:ach:ment shcndng the rough surfaces of ehe la.tcb., latch pin, and lace:!! sprl.:ig. Al~;o enclosed is a descti.:?tio:: of the pic::-~res and a dra~...:ig of che undervol~age trip attac=:euc 'lli:h che photograph nucbers indic:aced. Very truly yours, _,/'--*
" '7
.b.-) ;c.r~ i _,-/'
Gary J/. Toman Secci~u Leader, Qualif ic:acicn Analysis and Planning Section, Nuclear Engineering Dept. GJT/ih Encl. cc: P. Shemanski ) M. carrtngton) wichou; accachmencs
.:0th&,; Ra.:~ Streets. P.hila~elphia. Pa. 19103 (%15) ~8°lOOO TWX-110 670 1889
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SALEM ONI'I' 2 *s** ONDERVOL~:t Tm:l' ClttT A P!::otoa:achs of Late.a,. Latch :?in. !.ateh Serine, and Latch Retention Pin Picture Nul:lCer Oescri:tion of Picture Sur:fac~s
- l Side view cf latch showing- rcugh;.'ess of l~tch area .
2 Front view cf latch shewing latdl nctcll area 3 Front view cf latd:l with slight angle to right shewing face and slight mushrcoming cf latch edge* 4 tat=i lcckinq up intc the latch surface showing irre~ities and mushrooming cf edge 5 Lat=l spring showing wear and abrasion f:o= rllbbing on latch sur!ace (between arrcv) 6 Inside of l.atch loop showing surface that rides on latch spring retention pin 7 Latdl sprinc;J :etenticn pin showing poine of contact of latch inside .locp edge (betveen arrows) 8 tatc!l pin showing surface and edge wear f:om latch 9 'I'Op view of late: pin showing wear
?ictures taken March 18, 1983 Description prepared March,21, 1983 4
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~~~~ Franklin Researdt Center A~al"nwF.....,._
SALEM EVENTS OF FEBRUARY 22 AND. 25-, 1983; FAILURES OF REACTOR TRIP CIRCUIT BREAKERS; FINAL REPORT .-OF IN~TIAL INVESTIGATI9N APPENDIX E I
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"ftnklin Rese~~ch Center A Division of The Franklin Institute 1'1te Ben,amin Franklin Parttway, Phil&. Pa. 19103 <2151448* I~
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~rani<lin Research Center A Division of The Franklin Institute Ma;ch. 22, -l.983 Mr. Vincent Neenan Chief, Equipment Qualific:aticn Brandi o.s. Nucl.ear Rec;u.l.atory CQmm;ssicn Phillips Buildinq, MS-P-234/lU! P-234I>
7920 Norfcll Avenue Se t:hesda, MI> :ZOOM
Subject:
Salem EVenu c! February 2.2 and 2..5, l.983: :?ail~es of React.or Trip Circuit Breakers As yo12 requested,. encl.os1!d is the final. report of t!le Init:ial Investigation of Failure of Sal.em trnit l Reactor Trip Circuit :areak~rs to Trip on February 22 and 25, l.983e Yo s trul.u ti,,'/----~
=e~er.
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QUaliiicatico Analysis and Planninq Section, aiclear Enqineer inq Cept. GJT/jg Enclosure cc: P. Sheman&K i M. Carrinqton 20th & Race: Strec:ts, Philadelphia, Pa~ 19103 (2lS) 448*1000 TWX 710 670 1889 0
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Initial Investigation of Failure of salem onit l Reactor Trio Circuit Breakers to T:i'O on February 22 and-25, l.983 PrepaJ:ed by Franklin Researdl Center Much 21, l9 83
.Evaluation Investigation of the failw:e o:f the Salem Onit l reactor trip c:ircuit breakers to open when the undervoltage t:ip attad:lments (OVT) were de-enerqi.zed by the solid state protection system on February 22 and 25, l983*
inclwded review of.the operatinq, maintenance, and surveillance tesdnq hist=ry for the :CB-50 c:ircuit breakers used at the salem plant.
~o .ini:.ia.l i:ivestigation centered upon the OVT attacbment: ~cwever, subsequent efforts included the interac1:icn of the tJVT attachment with the c:irc-.:it b:ea.Ker. '!:be t:ip lever of tbe UV'? attaement must lift t:!le c:ircuit breaker t: ip bar for openinq of the circuit breaker to occur.
'?o date, two possible failure mcdes llave been deter:llined fer the Salem 1Jnit l TJVT attadlments. ~e first was observed by the Licensee and by N1C personnel the day of and the day a£ter the ~cruaey 25, 1383 event.* 'l'his failure mode apparently occurs when latcll-to-latdl pin binding prev.ents unl.atdlinq of the TJV'? attachment, there.by preventing the trii? lever f:om lllOV'inq wl:len the device is de-enerqi:ed. Shortiy after the February 2S event, all but one of the failed devices were luoricated and no furtller failures tc operate c:culd be repeated. ~e :emaininq failed tJVT attachment was subsequently damaged and was not available far inspection.
'l:he second possible failw:e made was reccgnized from inspection of the
."JVT attachment prcvided ta Franklin Beseard1 Center (l'SC) by the Licensee. The latch. sprins*on this device exerts enough force on the latch to :educe the output force from the trip lever as t:be friction increases between tne latch spring and latdl with aqe and lack of lubrication. ~is reduced fcrce could be significant if the farce required ta lift the circuit breaker t:ip bar is higher ~an no~ly expected. Ori March µ, l983, Westinghouse Switchgear Divi~icn representatives stated that the expected force required to lift the
~* -l-u:.JU Franklin Resun:h Center 4 0.-. al 'nl&.F---...
circ-.Ji t breaker trip bar at time cf manufae-:ure would have a maxi::lu.m *cf ll ounces and a normal range cf 20 to 28 ounces. ~ March l7, l98:3, ?R: personnel measured 28- to 30-:iunce lift force requirements on five cf six Salem reactor t:ip circuit breaker~ made available for inspection by the
- Licensee. 'rhes~ were the four Onit 2 circuit brea.kers and the onit l *a*
bypass circuit breaker. 'I'he sixth circuit breaker, the present onit l *A* trip, requil:ed 38 ounces cf *lifting force for operation, indicating* that reduced output force trom a tJVT attachment coupled with a high trip bar lift requirement is a possible condition. Durin9 the investigation, vuiations in construction were noted amcng the original OVT attac.'lments supplied to the SaJ.em plant. ~e device given to FIC had a tight latch spring. 'I'he remaininq device that was made available to PB: for :inSpection had a mudl looser latch spring tnat exerted no force on the latdi excep1: during actual latching operations. No reset lever spring ac:ijusaent* lode washer was found on the device provided to ?R:, whereas the remaining Salem device had the. lode washer. Discussions with NFC and Licensee personnel indicated tnat similar variations were noted in the other OV'l' attadlmeuts that were no long-er available for inspection by PBC.
'?be latc.!l surfaces c..f t::ie oriqi.naJ. tJVT attachments were found to be in the as-stamped scate. P.oughness was noted on the late-to-latch pin face and on the latdl-to-latdl spri:iq face. On* the device provided to FBC:, this roughness on the latdi spring side of the latch had caused a 9rcove that is al.so rou9b to be worn into the spring. Irretgularities on t.~e latc!l-~latc.!l pin sw:face of the late were noted on the E'lC device and the device tested by the Licensee. During-testing cf the F!!C device, hesitation during unJ.atching was observed when voltage_ was graduall.y reduced to the coil of the device, further indicatinq friction* in the iatdi-to-latch pin surface. Photographs of the latdl, latch pin, and latdi spring surfaces- taken on March l8, l983 shew the il:regular nature of tbe mating surfaces.
- Subsequent to the manufacture of the Salem tJVT attac.lulents, Westinghouse c.!langed the manufacturin~ procedure for the latch to include hand honing of the late!: surfaces that mate with other components.
on Maren 17, 1983, fie personnel. examined the new UV'? attachments supplied for Salem onit l. 'ttl.ese devices were found t.o*have "the latcb-t:o-latch- spring surface honed. Other surfaces could net be ~Yamined because the devices ~ere mcunt.ed on the circuit breakers. Variations in late.~ spring force were noted, and one 1JVT attachment h3d spring forces similar to the original. device supplied to FlC for evaluation. on Maren 18_, 1983, Westingllouse.SWitcbgear Division personnel indicated that quantitative acceptance c:ite:ia have not been set for the CVT attadlments. No output force reqQirement bas been set and no quantitative requirement for medlanic:al unlatdlinq capability exists. In addition, no such requirements lla.ve been set for fieJ.d testing UV'? attachment ope:ation and circuit breaker trip bar lif~inq force. Conclusions
~ bel.ieves that'in the as-manufactured *new* condition, the 1983 WT attadlment will prope::ly trip a ci:cuit breaker that bas a eip bar force requirement that. is with.in the design limit of 31 ounces, and would probably consistently trip a circuit breaker with as-found ~ip bar force req-~irement of up to 38 ounces. Eowever, sufficient evidence has not been presented to shew t.~at current manufacturing processes for the UV'? attad:lment when coupled with maintenance will eliminate lcnq-ter.n failu:es that appear to be mechanical, age-related pbemcnena. '?be variations from device to device cause concern. inie fact that boning is a hand operaticn*indicates that variations in the surfaces of the la.tdi will. remain even though no extreme rou¢ness should be expected.
In additio~,, the lack o~-quant:itative acceptance criteria adds concern i. I, that impending failures might.be missed during inspection and maintenance. on Marcb 18, 1583,, Westinghouse SWitchge~ Division pers~nnel also indicated that the CVT attac:bmen't imst be replaced some time during the life of the plant. Criteria fer determining when to replace the CVT attachment do not appear to be available. FllC
- recommends the fcllcwing actions: *
~UUU.i Franklin Research Center AC.-ol~f,_._
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- l. Acceptanee criteria be set fQr parameters a.ffect.inq correct opera~
of the WT attac:fuaent. ..
- 2. Testing methodology for ac:::eptanc:e tests be prepared for facto~ and Licensee use.
- 3. oniformity of const:uction be instituted or sufficient testing be perfor::ied showing that the variations in the devices are of no consequence to reliable operation.
- 4. ~sting of the OVT attachment be performed to show that the device can successfully opera1;e for the. intended lifetime with proper maintenance.
- 5. Criteria ?e developed to deter.nine a replacement interval for.the tiV'l!
attachment such that replacement occurs significantly befare the possibili~.f"cf fail;ire. Data and information prQvided to date indicate that the lonq-tea reliability of the CV'!' attachment h.as not l:>een proven to be adequate. '!he reliability of the UV'1' attachment appears to be significantly.below that of t.:le OB-50 circuit brealcer to w"hid:l it is mated~ ?re pared by G. J. i:cman
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~~~~ Franklin ~esearc.'1 Center A_°'- ol The F - - ,
I .. TRIP 'REPORT: SALEM UNITl REACTOR CIRCUIT BREAKERS \ APPENDIX F
~nklin Research Center
. A Division of The F'ranldin Institute The Ben;uruft Franldin Parit-Ny, Phila.. Pa. 19103 (21'1 "8°1000
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Tri:> Reoort
~: SaJ.em Nuclea= Generating Station (NGS)
~= !-!arch 3l, l983
Subject:
Salem Unit 1 Reactor Tri'C Circuit Breakers Pu~se of Tri 'C: At lO am c:in ~rch 31, l983, Mr. v. Noonan of NH:, EQB mm, requested that Mr. G. Toman of PR: proceed tc sa.lem NGS to evaluate testing of the reactor trip circuit breaker. (R:Cla) trip bar force requirement and the undervoltage trip attadlment (OVTA) output fcz:ces perfocned at the Salem pilant~ "Initia.l repcrts of the testinq received by Mr. NoCa.an frcm the NR:: Begion l Resident Inspec~or for sa.lem*indicated t!lat the devices were not operating within the force requirement ranges dictated by the me staff. Mr. Noonan asked Mr. 'l'Oman to represent NRR on this trip tc Salem *and to request the following:
- l. Who performed the tests? (Company affi.liation and names of supe~isin9.perscnnel)
- 2. What ':est methodology was 11sed? (F!C toeval.uate adequacy of method)
- 3.
4. I.icensee is requested t:l prcvide pictures o! (non-lllandatcey)
- I.icensee is reqo..:ested to pr_ovic:Ie a copy of procedures used for testing.
me*~odology
- 5. I.icens:ee is requested to provide a copy of the data taken on al.l. four Sa.lem unit l *RrCl!s and tlV'rAs.
o*. Did Public Service Elect:ic and Gas Company (l?SE.&:G) Qua.lity Assurance personne.l witness the testing?
- 7. What is the proposed corrective action?
- 8. NIC will. app:ove corrective action prior to implementa~icn.
Al.l of the discussions with PSE&G by Mr-. Teman were to be in the presence of an NBC :aesident Inspec:tcr* from Be9icn I. Recort: IJpon ar:riva.l at Salem NGS, Mr. Teman met with Mr. w. Lazarus, me Resident Inspector:, Beqicn I. With Mr. Lazarus, Mr. Teman met with the foll.owing P~&G persQnnel in the Salem NGS General. Manager's office:
* ~klin Research Cehter A Chiooatlol'l'he F....., .._..
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Mr. R. :Oderi t: * - Vice President, N 1 clear Mr. B. :Midura - General Manager, sa..l.em NGS Mr. J. Boet;er - General. Ma.naqer ~ear SUpport Mr. Gore - (titl.e not kuown) Mr. v. Pavincidl - Principal. Engineer Mr. Ga.llagh e.r - Manager , Ma in tenance Mr. Toman relayed Mr. Noonan*s requests to this gro~p. PSE&G indicated that the testing was completed on March 25, 1983 and that the test equipment and personnel. llad returned to the PSE&G.' s Maplewood Energy tab. :a:owever, Mr. Pavincic:h, "who had witnessed the tests, described them through use of color pilotcgra;tis. PSE&G indicated that the tests were performed to obtain baseline data on the RrCBs and OVTAs and to ful.fill. me requirements. concerning OVTA output forces and circuit breaker t:ip bu force requirements. Mr. l?avincic:!l described the force measurements, which used a load cell in ccmpression or tension depending on the test requirement and a Visicorder gr apilical. reccrder. l?SE&G provided a copy of the procedure, Maintenance Procedure ':-94 Bevision O ~ wilic:b was performed on Marcil 24 and 25, 1983. '!he procedure contains all of the data taken during the tests and eac:i step is
~ked wi tb a PSE&G QUality Assurance* Division stamp.
Mr. Toman asked if Westinghouse was party tc preparation or perfoaanc~ of the tests. PSE&G answered tbat the tests were prepared and performed by PSE&G personnel. Eoweve.r, Westinghouse, Ea.st Pi ~tsburgh, personnel were expected on site at Salem NGS" during the afternoon of Karell 31, 1983 to review and ccmment on the results of the .testinc;. With. regard tc tile i;:Qotcgrapbs of the test setups, Mr. :ecet':}e.r stated
~at the pbotcgra;hs being shown were the onl.y copies at the Salem plant and t:b.ac they would be needed for the review by Westinghouse. Mr. Teman asked if Xe.rox copies could be supplied and new prints sent at a later time. Mr.
Eoetger agreed to this. The main tests of interest we.re t::ip ba= static lift force tests, trip bar impul.se lift tests, and OVTA impul.se *output tests. 'l'he requirement that the static trip bar lift force be 31 ounces or less was met on.ly upon Bypass Breaker *B*. Eowever, all. of the RrCBs* tripped upon il!ipulse farces of' one pound or slightly less, and all of the OVTAs exerted .impluse forces of 3 .325 pounds or mere. For the static pull test on the trip ba=, the lead cell. was set up iri tension with the pull. point as cl.ose as possible tc the point at which the TJVTA trip leve.r would hit the trip bar. For the trip bar impulse lifting force, the load* cel.l was used in c:anpression. 'the trip bar was ca.reful.ly given a manual. impu.lse with the lead c:el.l in the area of the OVTA's trip lever. Seve.ral. attempts were made so that a range of impulses brac:Jceting the trip/no-trip point could be recorded.
~nkiln Research Center Aa-otTheF_._
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. *_/_ .. _.. ~-*~*.- .. * .
Note: 'l:be impa.lse t=at was manua.lly applied 4urinq t:be test. ~y or may not approximate the impulse output of the undervolt.age trip attachment. No c:cmpari.son data. are ava.i1a.ble to show that the accele:aticr:is, strike velocities, and pul.se widths are similar between the manually applied impul.se and that applied by the tJVTA. For the lJV'rA impul.se output tests, the load cell was _placed 0.090 inches above the trip bar so that the force imparted to the trip bar. by the OVTA could be determined indirectl.y.
- Note: 'l:be method of testin9 the output force of the tlV'rA used in these tests may include additiona.l forces generated 'by the trip bar du.ring un.la.td1ing of the circuit breaker trip mechanism. These forces may add to or subt:act from the CVTA output force and could be t:be explanation for the wide ranqe of readings f:om 3.325 to 6.50 lb.
?R: agrees witJ:i P~ that, due to the variations between the CVTAs ami the RrOS, teseinc; t:be CVTM 011 the :s:ros is mere useful than testinc; the devi~s separate.ly. PSE&G llas attempted to take as much*base.line data as
?OSSible du:inq these tests fer ccmpa:iaan with fu.tw:a test data.
A c:cpy of ~e PSIU.G c:cmpletad t..est pi:ccedure is attached. PSE&G stated that:. comparison of required i=?*lse t:ip bar force tc 'CV'l'A impulse force output sbcws adequate margin and indicates mat no corrective action is required. BOwevei:, FSE:t&G wishes ta b.ave Westinc;hcuse review and concur with the test resu.lts. l?i!C makes no judgment concerning the va.lue of the data (see notes, above)
- With re9ard to personneJ. performing the. tests, M:. Pavincich witnessed all.*tests, Mr. B. Ricks supervised the load c:el.l tests, and Mr. acmancsky
** supervised the timinq tests of the zrc:ss.
Prepared by G.. ':Oman April l, 1983 G'?/jg
~nkiln. Research Center A ~al'T1ie FtWlda U....
.*. '-; .., '~.. . *. *~.-:
,: ~ - --* .
~ PROO:OlJR!: A-ll
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- ..94
....._ __ 't.l!'!.Z: S?ECAL DAT~ Ac=OIS:TI'(N OF Tm: #l CNJ:'!' ~~R
'~
J ~ AND BYPASS EP.E;.XE?.S
'**-.*~= !'!US :?liCc=:t)tl'?.E IS S~ ~~.
ALL COCCMENTAT!C!1 SMI.I. BE MA-~ IN ACCOROINa WI":H .ADMINIS'I'ItATIVE P~OO~ (AP) ll. .
' *~s.IS ?RoaDOR!: HAS Bn:N ~"'!ZWED AND OE~ TO BE IN COMPmra WITS
~c:mnc.L Si'ECll'ICA"nONS.
P-T!V. NO. 0 I
.,~~~~,qf SY-2..M~
DATE I I -
~
1* AP?~O\~ N/A
~*-*
- ... I II
~c~. Q~
AP'!=R~ N/4 OA~
,r- ND!: U:n:::. Ill I I
'\* APl?'RCV::tl N/A
.CAT.::
AI :U::v ~w'"ED OAT.:: N/A II'\ 'i'Jrk*,.;. I
~;/SJ SQ:.Z ~~'"!Zn'"ED OA'!'::
v . (~~~ MAIN!'. MGa.
~PR~
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s.o.R.c:. MTG. Ntl!'.l3!3 OAn:*
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~ Ol?S.
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APPROVZ:O i
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OA~
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A-ll. Enclosure l Pa9e l of l Rev. 22
- ~-:-~-=~;.~*~.--::':-- -~_-:,-:
SAIZM ~T!l:G STATION
~~O: OC'ARTME:rr MANt1AI.
MAINTESAN~ PRoa:I:lOP.E T-~ Speeial Oata Acquis.iticn of the i l Onit Reactor Trip and Bypass Breakers. The ~ose of this l?:::oc:edu=e is tQ a1low fer certain data acC!Uisition on the
#l Onit Reactor Trip and Bypass Breakers. Data is to be collected by the i'SZ&G Research Corpcraticn under the direction cf the i'SE&G Nuclear E.""lgineerini; Department.
Th.is Procedure is applicable to Salem Onit U only. 4 .l AQi:li.st..:ative Proc:edure (AP) lS - 'l'agg'inq R!2les. 4 .2 Ad:i.~ist:ative Procedure (~) 9 - Ccnt:::cl of Station* Maintenance. 4 .3 WeS-~hcuse E:l.eceic ~aticn I:lst:-..cticn :au.Uetin 32-lOO-U, Lew Voltaqe Metal.-E:nclosw:e Swit:hqear. -- 5.0 ENC!.OSUM:.S S.l Enclosure l - Breaker Positicn and Serial Nu:llb!rs. 5.2 Enclosure 2 - Breaker Position "As Found" Conr!iticn. 5.3 EnclQsure 3 - Breaker Position "As Left" c.:mdition. 6.0 ~~ONSI3IT~ As del.ineated in this Prccedure. 7.0 l?P.ECAOTIONS ANO ::t.DllT.AT:tONS 7 .l When Maintenance Procedures reqi:i:e wcrkinq arcand electrical equipment,
- safety precautions am.wc:k*habits specified in the Electric Production Oepartment Safety Manuiil*shall bl observed :by all personnel involved in the acccmplishment of those Prccedu;:es.
7.2 When slinqs muSt: be~used to acccmplish Maintenance l?rccedures, they shall
- be used in a.cco::dance with the requirements of Maintenance ~ccedure M2Q.
7.3 When Ma~tenance Procedures requi:e wcrkinc; en stainless steel. components of the primary system, the following items shal.l not be used: 7.3.l Carbon steel wi:e :brushes and scrapers. Pac;e l of ll Rev. O
*r-. -- -:-~-~*":""*"".&: .. ,~........ - ... :* .*.
*.* :*:.*** ..... !: :.~~-. *.
*-.-~:::;.
7.J.2 C!llcrinated solvents, e.q. trichlorethyl~e. 7 .3.3 Onapprcved ::ask.inc; tape, ot.'ler t.~ fo:: use on protective c . ' *. _cl.otlli:lq. i .4* In addi ticn to the no:::ial precautions taken when workinq around eleem..:ica.l
~.tip:nent as speei:fied in the :E:lec-==ic Pro:iuction Depart::ient Safety Mam:xal, care ::nust be taken to stand clea.:: of t.1le various mechan,ical mechanisms associated wit.11 these breakers.
- i. 5 :Se.fore any ~.ai:1te."lailce work i~ perfor.ned, make c.ertain that all control ci..""l:Uits are open and that the breaker is removed fJ:cm the metal-clad unit.
7.6 Prior to applyinq solvents to electrical components, ved.£y ccmpcnents a.re il:cune to the solvent.* on w-2 switches, no solvent cleaninq is re-qui:ed or authorized. Clean wit.'l d..~ clot.'l only. S. 0 ?~OiJ!Srr:"..S 8 .l ca.1;.._atic:i data:
- ~c:. "'M::N'r ZQm?MENT CLDRATION CLDRA."'ION NO~~~ SERDL N'CMSZ2 DAT!: OW- DAT!:
(l) ~t ~fJ.0(41-
, I PL-?t/& (0/Z~fi~ 1412~/J-3 (2) :rt-. :i°nz: [\ We.rs}-.~ ffi*oo;; S:t-+=1 s L:t. Is?. .J'/.y /a~
... (3) S.:~-v~;':. ~tel' 5"2.4? 4.iz "Cl
.:C..2~
(4) C:.ol\1"\r\""'~~ dl\ P~ \l 01" 8.2 ::::itar the ";s.s Found" seria.l r.i*::nte.rs o~ all fou: (4) Reactcr Trip and Rea.c=r Trip Bypass %ea.'lters on E:iclosm:e No. 2 before rem.ovi:q* any breaker ::rCZL i~ cabinet. c::::ipa.re serial ~s tc t.'lose listed in :::nc:losw:e No. l. Notify yow: supe..-,isc: of an-:r disc:epancies. 8 .3 Notify the Senicr I & C SUpe...-viscr tha.t all four (4) Ileactcr Trip and
- .eactcr "::ip Sypass :Sreake.:s'will l::le removed frc:::n their c:ul::lic:les am t.1lat I & c testinq will be required "after completion of t.'le Procedure.
perfrJ(fJ;;;:= Notification is :~ed due tc the I & C Oepart:nent's :eqiiirement tc Trip Master 1'esp=se 1"_.,e T~~b-r/B '3 Senior I & C Supervise:_ Siqna:ture 'Date Physical eis-:ance !:c:n f:cnt of t::ip latch face tc t::ip bar. Reactor T:rip :Sreake.r " ....... " *-'SS'~ II INSPECTION HOL:> POINT
':'-94 Paqe 2 of ll J
Reactcr T:'ip B:eaker "il"
~!:~SOP./\n'l'NESS INSPEC'l'lON BOLO ?OTh"'l' .
R"eac:-...or ::ay::..ass Breake= "A"
- 2.5\o StJP~SOZV'W!~~S
. \
INSP:C:t:nON ROI.:) POINT Reactc:r B'!{IlasS B:reake: "B" * .,28G,~ StlPEa'VISO:vwr:NESS INSPECTION BOLD POIN'1' ~ 9 .2 Clearance ~t:'*een -:rip lave: a::C: trip ba:
- Reactcr '!:ip S:reake: "A"
- I 2. ~o
StJPE:RVISOR,/WrrNESS INSPEC!.J.ON BOIJ:) POINT IJ
- \eacto:r T:ir B:reake: '"S"
- O/S' SO'PE:RVISOR/t'l~Tm:SS
!NSPEC'nON HOLD POINT Reactc:r Bypass Breake: "A"
- O~o I
INSPEaION BOLD l'Oim' e.eft**:~ ~~ 1" Reactcr Bypass. :Breaker "?5 11 * "":" e 1 '1
- O & C>
StJPERVISO~S ~ -~oil..,,;/' mSPEC'I'ION BOI.Il POM ~ Jl~ ;.f~
. '. . .~~r*_,-
__ . T-94 Page 3 cf ll Rev. 0
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9.3 Cistance :rem Cente= o! Trip Bar (Breaker Mechanism) am St=iJce Point of Or..dervcl:aqe '!:ip Leve:. ( .. *--... :Rea.etc: Trip Breaker "A" S_. _~2c:;- ,, . S'CP~SO~IESS
!NSPEC':'ION HOU> POn."'l' *.~S"1!:
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S'CPEltVISOlVWI"r.mSS (-* !NSPEC'IO.~ :!CI.I) l'OIN'l' \, 9.4 Measure ::orce Reqa.:ired to beqi:i to Cc::press !.atch Sprinq (Flat Phcs~hcre Brcn.:a Sprin;) Reactor '!:ip Breaker "A"'* 100 o .::s+O\C. (~*!~ S'CPE:&VISOR/WI~fS INSPEC.l:l.CN HOU> POINT I 6.i~-~~~
. ~~, ~oif:J \~~l~3 Reac:tcr 'i_ .:.ri :Sreaker *3 11 .2. 00 \1::i~'2.--~ ~ \~.,
SOPEltVISOR,/W!TNESS ~** IN~C'l'ION BOU> POINT Ar~~~ v:r~;Jf-1
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- Rea.etc:= Bypass Breaker "A" Uoc>a\e ~s:i .u.... :,, Rep~* ~
SUPERVISOR/WITNESS I?1SPECTICN HOU> PODrr
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T-94
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~~ .li- = 9?--A-~ ~ B~-.c-.\J?\-e SUPEltV:SO~S r.~~C .... ON BOIJj PO:Dn 9.5 Record Appare~t Conditicn of Latch Surfaces (Polish~ or Not)
Reactcr 'I'rii;> Breaker "A" 7~\ ,?\ ... }) - "'P~e...~,:S" efk.q_ J. \.o..~h. *
* \ 'l:'>i~ slro.~@ ('r\~,:-..,~ R.i~~-i.@. ~ .-~ ,,.-,rJL..l .
SUPE~SOR/WXTNESS IN?PECTION HOLI:I PO:Dn . *(~----2I.iJ>.~
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!NS~EC':ION HOI.:I POINT
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*, :.ea =. '!3*-S ... r eake: ,._,. ~
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- zNSPEcriCN BOLO POINT fg; BEMAPJCS: ..
. i ME:AStmEMENTS - SHONT *ntDS A1'TAC3MENT 9.6 Physical Cist.a.nce :frcm Shunt Trip I.ever Pin to 'I'rip*aa::
- Reactor Trip Breaker "A" * ~i"\o smi~SCR;WJ:TNESS .~
.-:.,~~' ,. SW)
INSPE~ON BOLI:I POXN'l' I ,,-~ c- ~
.-94
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Reac~cr :CyPass :Sreake= "An
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9 Clearance f=om S.T. Lever to T::ip Bar
- II Raac""..or T::ip 3: ea.leer *A* ,\\2.0
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*('* r.lSPE-r-:?C.': HO~ ?ODn'
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R.eactQr T:ip Breaker "1!"
- 0 s:.b.
Sin'~~OP.,ln'r.n:SS I:?SPECTION :!OI.l:) ?OI?:T Reactor Bypass Breaker nA" .o-;a St!PERV'ISOR/WI'l'NESS INSPEC.!..!.ON HOI.:J POI:rr Reactcr Bypass Breaker .n3* 0 St!PERVISOlVWZ'r.tESS ~-
- .t=<.s-~r**
INSPECTION HOLD POn:T A .1 l i-r r..l::.y-W"" '<::t::P > * , T-94 Paqe 6 of l l Rev. O
i* s.:. Lever.-
- rnS?Ec:r.:CN BOLO POINT
\-7." '1 ., '2. loq 'e>
Reactor T:'ip B:reaker *B 11
- NSPE~ON HOLO POINT ..
~ .. ' '1 'i 7"2.. (#Cl) \:>
R.eactcr B~ass :Sreaker "A" nGPEC!lON HOW POINT 3-z.~ y 7 ?.to~ e, _, . . z.., 'I 1'Z INSP!.:c:lON BQU)
'-~
POIN'!'
~
Reac:tcr T:'ip Breaker "B" Reactcr Bypass B:reake:
- T.. 94
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Reactc: T.:ip :al:eake.r ""A" 4*.~1o;-"'.-+,';°"7~ lb -:..c.i..:; \'-= ~~ro*z.i; H,- 3.li.~11:; 1 P""Ca~ Av~. ~ ~.~~ \'=~ ~ 1 1
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INS"i?Et...::.l.ON :S:CI.:l ::io:nrr 1'-\\ Av~ .~. ~ .... ~,,z.c; \\oi ~<:::..: ~.. ~>> Aea.ctcr Trip Breaker ~" F'u.t\ .:..Ce \\a 'Z..,\2."$"\\,. \.?i15'1t.. 7...eee\\,;, , *'"' . *"?
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.LON Hoi:c POINT .
Aea.C:-:cr T:ip :Srea.ker "3"
*".'75" \'a Stll'ERVISO~S. 'C$'C \~
* 'S"c:i '..la R.eactcr Bypass*Sreake.r "A"
* .,-o \~c, ~-c.\-eQ..Se
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T-94 Paqe a of ll
.. :* _J
9.l2 Fo:ce Genera~ed by Undervoltaqe Trip Lever on the T:ip :aa:. SUP~SO~S Reactor Trip Breaker "'B" INSPECTION BOLD POXNT
~~ J t:; ": ~ .;z. 'i' \'o~*
~ o"St .o~q
- 9. l.3 =orce Generated by ~'lunt Trip Lever on the Trip Bar.
-* Reac;:tor Trip Breaker "A" StlPEAV!SC~
Rea~..cr Trip Breaker "'B* INSPECTION HOLD. POIN'r_ SCPJ:!RVISC!V'WX'!'NESS INSPEC'nCN HOU> POIN'l' Reactor Bypass .Breaker "~"
..... ....... StJPEX'nSO~TNESS ~
I
*,
- oc; -{~St')~
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*-94 Pa.qe 9 of l1
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Rev *. O
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9.14 { \ ... **-,
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StJPERVISO~S
!NS?EC'l'ION*SOI.D PO:tNT Reac::for T:ip B:eaker "B" StJPEAVXSO~ITNESS INSPECTION HOLD PO:tNT 7'*/p ri"mti!! ~;,
Reactor Bypass Breaker "An S'~e.o,.er. ., ...
-c:
INS?ECTION HO:m POINT
?.eaeto:r Bypass Breaker ~*
INSPEC'!l:ON :s:o:m POINT INS?EC"nON HC!:r.D POINT* Reactor Bypass Breaker "~" StJPERVISOR/WI'l'NESS INS?ECTZON ROU> POINT T-94 ::?aqe lO of ll :Rev. 0
- 9.2 ?.ei:stall all four (4) ~..or t i p am Bypass :ar~s in their respective.
~icJ.es as indic:ated en Enclosure ~1. P.ecord on Enclosure 13 *
(SW) INSPEL.llCN BOU> POnr? (IBP) lO.l Notify th~ I & c Senior Supervise= that Maintenance* has been
':. cc:i.pleted *en all four (4) Reactor T:ip Breakers and Reactor
'r:ip Bypass Breakers on i Unit. I & c Oepa.rt::nent c:an proceed with their :r:~i.:ed. t:i:ne response testinc;.
I Seni.cr I ; C Supe.rvi.scr Data Time 11..0 Proced~e c:cmpleted: ll.l
~---
Sa.tis~a~..cry
----- tlnsa~actcry ll. 2 Remarks :
ll. 3 'l'est perfor.:ted by
- ~o:;;;r:,o.-* ...,--=*=.i:k;::;:..---------
Siq:ia-=:e Oate ll.4 Reviewed by: . - - - - - - - - - - - - -Supe:visc: Maintenance --------------- Cate QUa.lity Assurance Oate C:..c.1.~~c..-T.~ bo..-T-4'
. c.-~~ ~~ 4.\\\
E.9-*°'""~" ~ I
.~~\ca,.\ ~'°.
~\."'~'"" ~-;.""
~ S~c..-e~*,~~ 'S~ .. ,"\ \ ?~u~ ~" IJ.S.-C. r... ~c.~ ...a..;.~.,_ Sc:.l4 *. iiolc
- ~~"~ "S~~*
<:.w.p~ . Pe-oc~ ~-a-ie::.
~. ~~; ~~ \.\) t>"" 0""
°J. S~c:..t.u*i-~ !:ic.fo\
/~. 11.,;t~.,.,.11 wi:~c..~
'-2 \ '?tt, PA ' 6 iC.. . -i-o
?~,;,.. ~ c.J.:e.
-?o u.~~
U.l> -e - I J.L~~~. . . . .4u. ?J..,oN aa . c,) ~ ~
'. rP ' Gc:-e 1 lu* I P-:Z...
T-94 Pac;e ll of ll ReV. 0
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. . . -~* . .. .. . . . .... ' *:.. " "': ~:_~;* ': . /.: . ' .,., '. *. '* :~*- *,* . . .. . r'
.MA!N'nNANCE PROC~URE T-94 .*
ENCLOSURE l BREAKER SERIAL NUMSE~ AND POSITIONS SERIAL NUMEER: l24Y7268B 124Y7269B 224Y7268B 224Y7269B 324Yi268'B 324Y7269B 424Y7269B 424Y7269B A TRIP A BY-PASS 124Y7269B 324Y7269B B TRIP B BY-PASS 224Y7269B 424Y7269B Enclosure l Rev. 0 Paqe l of l
-;e
- !"~~ANCE PROCZDOzr:: 'l'-94 "
ENCLOSURE 3 .._,..*:1
. EREAKZR ?OSIT~ON AS U::'T CONDITION .
UNIT il
\
A TRIP I _____A __s_____...I __B_Y_-_P_AS B TRIP B BY-:?A.5S
~'"l't.erea ~y:
Reviewed By:
.Maintenance Supervisor Quality Assurance
~-
*- ~
*. Enclcsu:e l Paqe l c:f l i:iev. a
*-~
.APPENDIX C Wes: ingl'Hl lS$! Wat!r Reacicr E=:nit Co;porati.on O~iOns
\ NS-EPR-Z737
~rch 22., l983 Mr. H. Denton, Oire<:tor . .
Office of ~clear Re~cto~ Re~ulction U.S~ ~1ear ~gulator-Y CDc:ni s$ion Phi11ips Building 7920 l-brfo1~ A~enue Bethe~da. 1"l} 20014
~al"' Hr. Oen-ton:
Tht! ?Urpose of this let.ter ~ ~ to provide you ..,*th tne 1 ~test h~formati on on>- lij,estingtl~use iru1es'tiga'tion into the malfunctions of the Sale=
. P1 ant rea4;tor tl"'i p switchg~cr. Our inves*t~ gati on, a 1on9 wf tll analyses perfo~d for the Sal~m ?1 an-:, d=onstrat!!s that the 'ifes'tin~use pl ants wi"tr. tM s iequi pment c:.:ara continue to operate wr1 t.~cut undlJ@ ri ~ to pub11 c
- llea1th a~d safety.
On ~r-Cn Z0-21, 1983, Westinghousa perio~d a detai1edll proe~durally con~lied fnsp.:ctian of the unaervo1uge trip {UV~ at'tad'lment t21at was provided tg Westi ng;,ouse and was r9presented by ?S£&G && tne UV attachment. that malfunctioned on Reac:t:)r Trip Sreaker S at Sa1e11 Unit 1 on F~bru.ary 25, 1983. P!1ot.ograjjt?s !nd an aud1 o tape recording of the P'arch 20-21 1nspe-etion are. available at ltestinghcusa fer your review. A. detailed ..-Mt-ten 1nspect1on Mtpa~ is being-de...e1oped fl"m ttds eva1uat1on. io o~r.kno-wledge, tn;$ is the only such detai1ad inS"?eCtion condtN:ted ta date of a IJY attachment rei>rtS1tnt.ed 1s OM of the tllo that u1fllnctioftt!d on Februa~ 25, 19a3, at Saleti ~it 1.
- In pre~aration fo,-
this 1n$pection, Westinghau:e dew1c~d a list of i::ostuhted malfunction sce:narios for this devic*e (s.ee Tabla 1) *. Thi' 1nspei;'t1on w.as conducted 1n order to es~b1ish whicn af th41se potentia1 scanarios 11igh't have produced the mal func~1on of the Sale11 Unit , devii:e.s.. me fo11Clring 1s a s~*rY of the key* findings in tbis examination.
- l. /4s l"'eceived fro= PSUG. the UV device wou1 d not 1 at.ch. ~ was also 1 hist.cr;r of bt"eaker c1osure prob1r.zrs on Reactor Trip Breake~ a
;s repo!'"t8d in the !ilRC TasK Force Report. MUR.EG 09i7. .a.s a ~sult.,
the test circu;t bre1ter on ~ieh this device was installed c~uld not ~ clo$ed ei~r e1ectrical1y or manually. Th1s ;n.a,bi1ity to ..
latch tile. UV deviee was traced to a bent and deformed -phosphor--
- bronze leaf spring which ..ould not iaaint41n the p1"Qpe~ fo~e against the traveling lat.en mechaniSl'I. ~ defoM11ation observed en the leaf
-sprl ng c~ul d not l'lave !:>een caused by nQr:iN1 operation or wear of this deYice. Had this UV device been 1rista11ed on Salen lkJit l ReactrJr 'rrip Breaker Bin t.ie condition.as rei:eived by Westinghouse.
ft would have been d1fficult to close the associ~ted circuit breaker. It should ~e notad that. had tM s part.i,ullr'"1eaf s-prl ng been e~c'ifssi vely defor:ied against the trave11 ng 1 at.ch, the IJV ~Y'fce could tfave ~n prevented frt.im unlati:hing aut~t1cally thus preventing the bre~ker from opening. A Wes ti oghouse repn!sentative sent to the Sal em site en February 27. 1983, noted. that a 1eif spr1ng ...as deformed on at 1east one !IV device shown to him at the sit~ by ?SE!G perscnne.1. Tni s cievi ce was described U> hi a by PSE!S as one of the !JV attachments that ri;a 1functi onad .on February 25, 1983, at Sal em I.hit l.
- 2. The axmi nation at 'liesti nghouse of the UV ~vice disclosed a 11fssing *
- 1oct washer on the drop.out voltaie ~djustment SCr!':i *Chani sm. The l!Cfj ustment scTew was e.xcessi ve ly turned*i n*, a condition wM c:h reduces ~ un1atd1ing fon:e available llhen tile UY deVi(;e is
*ene1"9i zed.
....., In ~'le ~s-l""e~eived eendition. a visual !xam1naticn psrfc~d by
'Jesti nghouse revealed that the device -.as 1 ubr1 cated. PSE!G r..as advised ~stinghouse that a l!JDrii:;int ~s adde<i to this 6evice after tne event of February 25, 1983. ~sti ngnou:se is cur:-ently uia1yzing this iubMcant in order to de~r!!ine 1ts t,ypa.
- 4. 'Near on the 1 atc:h and latch 1 nurlace was not excessi 'fe 4nd there
-.as no evi aence of burrs. Hcr~ver, e.:ccessi ve frl cti or.a 1 fore~
cannot be ruled out as a ~o~ntiaT malfunction scenario since p.ost i!"tCident ha.0011ng {manualiy exercisi!i9 the device and lubrication) prier to ~ceipt by *iestinghouse cou1d have raasted a friction force
!:la l f\mct7 en s:anar1 o.
No v1s1ble ~videnee w~s found of corrosion or brcicen or is:is:sing pal"'t.s, other ~n tne prev1ous1y *ntfoneci lock washer. There ...ere no obvious $.i;r.s of 1mproper nanufactura.. A check of each p.a:-t against ~ified dilll!nsioos and toleranc:as is being made. Fu~'t1onal tests ~nstrated that tne device -was ca.pa.ble of
~rlom1n9 1ts electrical* function.
- 5. Artificial res-:ra1n~ of the UY device reset IU'"1 was requ1red to
;;easure t?le tr1p lever fo~as ~r.eratea by the UY device. The tf/st breaker w.a~ "tr1 pped normally by the U.V at*tK.tnent on severa I atte!%:pts liiUl nor.!a1 tr1p Dar 1oad o( 1.15 pounds and )lf'1tn an 1riCM!ased 1oad" to Z.3 pounds.* A furt.her fn<:rsase in trip bar 1o.a:d to 3.3 p<>unds resulted in eri"a't1c breaker tripping by the UY dev1 i:e. The mu1&W:B e.xpect.ea fort:e re qui rail to actuau the tr1 .P bar
- i!037Q
on a normal 08-50 b~atar is 31 ounces. lience, it wA$ concluded tha:t the UV at.tac:l"lment was capa..ble of providing sufficient fon::e*
- with ~e1"'9in, to trip a properly "Cainta1ned pB-50 circuit b~aker.
Sased on. the above infonaation, this e~aminat1on appears to rule out the postulated ~alfunction scenarios l throug!l 6 of Table 1. The effects of dirt/contamination (mecnanis::a Sl could net be evaluated due to the lubricant applieij to ~ device af't2r the events en FebMJar.t 25, 1983. Eviaence of misadjus~nt of t:ie drop out vo1tige adjustment scr!w (£lechanis:i 9) was present and may ha~ ~en a contribut:Jr, but lta.S not, in itestinghou.se engineer-ing judgerAent, ~sole reason f.or malfunction. Based en the resul'ts of this ~xanination, 'tl1e C1U11funct1on Qf the UY attacr=ent was not cttributable to design or :nanufactJJr1ni;. The
?QStu1at.ed lll41funct1on scenarios which cannot be eliminated or whtch were present in the examination fall intc four categor1es: l) frictional ~~a ano=alies, 2} dirt/con~inat1on. 3) bent or .defoMDed **
parts, and/or 4) misadjust=ent. These fgur categories a~ considered to fall under orre bN>ad cate9ory of mainter.a.nce r"1!lated causes. Sa 1e!ll Restart He1' uv trip attac.ments- nave ~n 1ns'talled at 5.aleii Unit 1. Thesa devices wer-e ~cent1y built by We$tingh0use and certifi~d as manufac":JJre;j to cu~rrt Westinghouse specif1c.atfons, 1ncluding 1ubr1 ca t1 on. 1hey llll!M! *subjec4"2d t.~ Z5 conseetrti ve opera';i ons without naifurction at the Wes~ing..-icuse Switchgear 01v1s1on and. after
*r.sta11ation a"t Sclle11 lh1t 1, were sU!'Jjeo:t~c t.o at 1east. 10 add1t'!on.,1 peraticns also without ulfunct.1on1ng. _
$1estinghouse nas sen~ a ccmpleta pac~age of Tecnn1ca1 Bu11et1ns and Data
~t't.ers to P-:::..E~G. A r.e11r*1e,l"lni~al Su11e"tin clarifyfo; the c1rcu1t.
- br":a~er and und.enoltage trip at.tacht:'ient. 1ubr1cants an¢ lW>rlca"tion p.o1nts w111 be 1siued to a11 West1ngnouse plants, 1nclud1ng Salem, by.
Jilaren 24, 19-a3. 'lifesti ngtiouse na.s evaluated tne ~ormended 1uDr1c~nt in th!t bul 1et.i n and has- d2tsm1 ned tt\.1t 1 t does not p~duc2 ccrrosion af
'the undervo l'tage atuc:tsaent maur141 s g1 ven the equ1 prsent oper!t.i ng env1rQnments and 1uDr1cat1on s-pec1t1cat1ons fer tne Westinghouse-suppl iea OB-SO reacur 'tMP sw1ti:hgear.
- West1nghouse analys1 s of the S41em events, tnnsrit.t~d to 1ou en March 14, 1983 and 1neluded as Attad'Dlen"t 1, ~onc1uded th&t the pub1fc be41tn
~nd safetY ..oul d not have been affected had the ~~nt gf the Februar.r 25,* l 983 OCCUM"ed at .full J)C.er *. 4dditiona11y, if one of the t.o no"1al1y operat'f~g l'Min ffftiwcur pusnps ~T"I! 1ost 4t fµl1 power, ~nd if t:le operat.Dr ae't1on tg unual1y trip the ~actor did not oc;eur for five fl1 nut.es, tne resul Unt prima17 s1ste11. pnssure* wcu1 d have been be low the pressur1z.er relief valve set.+10irrt. Furtnermre. for the 1e:s 1ikal1 case of less of 111 main fee0t~ter pi::z:ps, opentcr 1c:tion at 30 ~t:cnds
- l.cul <1 nave resulted in pMear.r systera pressuM! r-eachi ns only the relief valve ~tpc~nt. OperiJt.Or action at f1Te a'inut:s, upon loss of t:ioth feedlfat.er pr.a:ps, and with a reslisti' l'IOd:ratgr cc-efficient, would have resulted 1.n a primary sys't-""'m prt!ssure which ~pproJiiinatea the AS1'E Code
- 4-037Q
- SerYice l..!Ye1 C 1i-:a1t of 3200 psi a,. the ~stabl1shea accep'tanc! criteria for t.'\i s event. This sequen;e ...cul d have requ; red the ope!"at.GT" to ignere SC?ven 11e,Jor tMp demand alan;s. Even if the reactor-.. trip b-reai.ers -..ere not able to be tripp&d mnuilly*fraa t!'le control roes.
- there are other diverse 11eans ava1-1dlle fora the Salem o~rators to acc~plish a react.or shu~down &s prescrieed itr the'tl"" ATWS s:inx2dure.
~t the'°'fOM!, r:cnc:1Ude that even if the hfghly unlfkely event -ere ta oecu~ at full power, there would De no effect on pub11 c he&l th and safety.
6f"'n the results of this analysis, other nieasures illPO~ by *the HRC, wM1e l"!Ot. ~cessary, prov1de additio.nal iaargi-n and shculd prov1~ further ~gulator.t ccnfi denc! that Salem Un1t 1 can be resqrted safely. For exup1e, manual reactor trip from the control room after an au~'t1c tr1p demand .exerc'f ses both the undervoltage and shunt tr!P ..... attaci::ents of the DB-50 ntactar trip switchgear. ;fe$t1ngncuse has con<luct.ed recent tests on a shurtt trl p att1chllent and has detenai ned the dev1ce genere.~s a force at least JOm greate,. than t.~a fon:e necessary
~o tr1 p the b~ater. In response t;) HRC IE Circular 81-12. liest1nghouse 1 s pre?ari ng a Techn1ca1 Bc.111 e't1 n giving ~ca-.iendat1 ons for independent . testing of the unoe~vo1tage and shunt trip attaeh=!in~s for manu41 l"!ac-:or t:"f p. .1li1 s Tedini ca 1 Bul1eti n wi 11 be 1s:sued to all West1 nsncuse p1 anu, 1 nclud1 ng ~la, by Maren ZS, 19S3.
IJY Tr1 P ..!.tt.ac:h=ent Desi an:
- A't tM C.O:sn'f ss1 crers' 11eeti ng of March 15. l 963 t.4ie NRC Staff e:i:pressed uncerta.1n-ey over the- UY "trip at.t.acha!nt design 11fe'til:ll! and the foherent nzal"'1i n bet~n the tM p force generated by the undervo 1tage trip 11tuchvaent and t.ie forr:t requ11"9U to 11 ft tbe bre.ake ~ tl"'f p !><<r. 'iiie bel1eva ~se uncerta1nt1es have eeen n!solved by furt.M-r infonsat'fon ..
Tests ccndue~d bY PS£J6, F'rank11n Flesea~n Cen't!!T", and ~st1 nghouse f ndieau a nanna l tr1p farce marg1 n of loo-zoo perc2nt. .A1 sc, in 19i2 an uncteMQ l tage ~rip attad=ent, lil0d1 f1 ed as a ~su l t of 3 re po rt!d UY a1funr:-t1ons at Rcb'f nson Unit z. was suc:cessfully usud for more than BOOO. oper&ti ons without 1al func-t'i on. "t>>d1 fi ed undervo 1U.ge trip 1ttaetcents ~~ sub$equen~ly sant as replacements to all operating phnts with DB-50 reactor tT1 p sw1tchgear *at that t'fm. A1l subsequent Wl!st1 ngl\ause manufactu~ of under'tOliage t"r1p* attact=ents h4s i n=orporated the =odi fi cat1 orts Mele in 197~. A ntvin of cva1l~ble t.ERs on ves~1nsnouse l1Y trip attachment lt4lfunc'tions si nee Uie 197? mod1f.1ca~n 'fnd1cate. that appn>xii:aatel,y t'ifO-thirds of t:ie ralfuncticns appear to be. so'fntenanca ~lated. The overal 1 d~t~ for ~.alfu~icns pe,.. demand en Wes't1 ngnouse OB-50 ci r"Ctrlt breeke:-s has ~n appli.ed 1n pla~ PRA $~Ud1 es and has no't snown an undue- ~ontrlbut.1on to tQ'bl p~11 ~ r1 st. In view of the ~bo~, the c;un-ent design of. tl'\e OB-SO reactor trip switchgear f~ a pT'Qper ~pp1ic!.'tion for n*uclear power plant protect1on sys~:s ~n properly fnstal1ed, tested. and 11a1nta1ned *
- 4037Q 4
- Not'w'ithstandi"9 the foregoing, Tr.I- let~er to you Qf March 1, 198.3 COl2nitt.ed to a tnerough evaluation and ~st.ing pro9rar1 of the UV trip attacf'slent to be c~leted by June z. 1993. Test objecti~s and 'JH'"09r"aJI definition ar"'Q Q.x;per:ted "to-be e=-plet.ed t:>y Mare?\ 25, 19a3. FurthQn::wn"'t.
we intend to do an ; n-depth analysis of CB-SO r"1!act.cr trl p swi tchg1iar ma1funct1ons-'w'hich have ec::urred on oper~t'ing nuclear p1ants to provide* additional .data t.c further ~nst.rata its r-eHability. This reviQW wi 11 be based on hi sU>ri ca 1 LER data uld an1 O.fini t1 v& data wn-t ch lfe ean obtain frOfl ou.,. o~rat1"9 phrrt cus~?"'S rehtive to wtal m.Dbel9 of reac;t.or trip ~MIS and l"Aa 1functi ens reeordad.. We of the esti~&tQd_ completion data of ~his review. wi,, advi $8 !fOU . :t P1ease contact me if you "'°u1d Hke tc di-'Z:uss this -zat't!!Y6 further'.
~r'J tMil.Y yours, Vt~,~~.
E. P'. Rahe, ~U9C.,.
>bJc:leir Safety ~p.artaient Attactnent($)
s
T"b1 e l
- 1. Corrosf on:
Postu1 ated >ii.a 1tuneti on Scenario'
\
- 2. Missing Parts
- 3. Brotsn Parts
- 4. El~'trical Failure
- a. OUt of To'e~a~e Parts *
- b.
- JiCi sas~ l;r Insufficient irip Force Frict1ona1 Area ~lies
- a. wear
- b. Burrs9 H.!Jllj-U?S
- c. bubt1caticA
- s. Di i-t/Cantam nati en
- 9. Mi $adju:st:aent 1O. Bent or Def orsed Parts
- 6 4037Q
t I ATTACHMENT. I I An~1yses of the Salem Postulatad .Feedn:ater Malfunct1on llrit.hout Huc1ea~ P1ant fQr .. tl""c Automatic Reactor Trip II: t:
"1C'
~
t.,.
'WESiINGHOUSE ElECTRIC CORPORATIOH ~
i'l" M. ?. OsbcrM ""#-c
.Trans1t:nt* hla7ysis
~c:le.ar E.afety Deparur~nt * ~"
ApprQved,Y~ Jlt~/t,
~
** /J; t\IJ ~1t'Z1e, ?.ami.ger
.'~
~
'iransient Ana.lysis ltJc1e~r safety Department i
.i
~
( l l.
' ~
i l .. -
~-:--'-.-. **--*.--* ~ : .*- ..... - --** - - *-- -.-*.--*.:~.- *"'. ~--.***--*. -*-*
. ~~~~--'---~_:__;__~~~--***_**~*~~-~~~,-~:--==,***=*~*~=---~
SCOPE In light of.the recent fai1u~s of th! ~~ctor trip breakers ~o
- automat1ca11y func~ion at the- Salem p1ant, the PU1"¥0~e of th\i s~udy is to reali$ti~al1y predict the consequences of a failure to ~Tip fer 1imiting plant transients whi1e the plant is at full reacto~ power. The trensients analtzed. specifically for*the Salem plant, ~r2 a paJ-tial loss of ~te~m generator main feedwater (1ow*due* to the trfp .of 4 sfngle main feedwater. pump and also a *complete 1oss Qf main teedwa~:-* flow due to the loss .of beth main feedwatar pumps. ~e latt~rt less p~ab1e,,
event is that ?~sented in the Salem plant FSAR. As $t4ted previously, tna purpose of this study is to rea1i~tic4lly predict th~ l"'tS~onse of the pl~nt to these event~ and. as such, the plant ~y$tem~ are assumed to function_ norma17y. with the so1e exception l>eing the c.Qnman mode fai1unt of the r*eactor br~!ked to *automatical1y function as -wa~ !!'.7.'fti!'T*ienced art February 22 and 25, 1983. It snoul d be noted that t.'\e sl)uri ou.s steaw generator level trip generated on 2/ZS/83 wes as a ~~$Ult ot nonnal expected feedwate~ control syst~m di fficu1t1es expericncad at -1ow n1i1 . - power ievels. l~ also should be noted th4t the loss of a fetdwater pump on 2/22/83 was* due to a nonna 1 manueveri ng of 4n a1ectriea- l bu:s whf1 ~ . configuring the p1ant 1n p~pa~ation fo~ a pc~r es~~l~tian. Both of t~se events are net normally expected at ful1 power and thu$ one should eonsjder mere credib1e events such a! a feedw5ter heater dra~aut r~ther tian the more i'fmiting and mui:n less freqyent feedwat&r pum~ ma1functions. The study consider~ a*thirty seeond.oparator r@~pOn$e time for 5 manuai reactor trip fo11owing the automatic protection system demand ~ign!i, a simulation of the actual response ti~ of th! Februa~ ZS, 1383 event. The study al so ~cns.i ciers a more c:onserva.ti ve cperi!to r respDnse of five minutes in order to detenni'ne the sensitivity of the plant ~sp1lnse ta op~i-atcr action. O::SClUPilON OF TRA~SlENi £FFtCTS Gene~ic studies (We.AP 8330 We$tinghouse Anticipated l~ansient~ Withal.rt Tr~p Ana11sh) of failur-e to tr1p events previously s.ubmitt;-d t.o the URC have identified the 11m1ting full power events to b~ malfun~tions dffect1ng st2am generator main feedwate~ flow. The redu~~ion in main feedwater f1ow affects the overall heat remo~al capabf1tt,r o~ the steam* generators and, as a result of the m1$1\atch bet'llreen th~ prfmary Sida heat generation and the secondary side heat ~movat ~roduce$ a heqtup of the primary system coolant.. If the reac:t.ar is tri~?ed prt=ptly > the *. auxiliary feedwater system pro~ides suffi~ient heat r'moval 1;*~bil1ty to remove decay heat. ft>wever ff. feedwater fl ow to ~ie s"team generators is red~ced or te:nninated without subsaquent*reacto~ trip the $econdary
~Y~ tem ~ 11 be unab 1e _to remove a11 of the neat tna t is g~n&rated in the core. This heat buildup in the primary system is i t\mcticn of the amcunt of the feedwater roeduc~ion and 1s 1nd1cated by risin9 ~actor coolant SY$tem temperature an~ pressu~. and by inCf"l!4Sfrt9 pressuriter water level due to t.ie insut"'ge of the ex~anding r!actor CQ~l~t~ Wa~r 1eve1 in th~ !team generators drop5 as the remaining 1nven~~ 1n the steam generators 1s boiled off due to inadequate spply ~f f~em.ater.
When the ~team generator water- level falls to the point **he?'!!' the- stem gen~ratcr tube buncf1 e i $ uncover~d ~t'!d pr-1ma ry to se-conau*y 'heat
. * . transfer is reduced, reactor- cool ant system pr~$sure and temJ:>eT'ature z
3999Q
--~--__:_*~ ***-~- *.**--* ....... -* ...*. *-:**-*_*-~.--~*~*-~**-~-*__,__
.* =----:s--=*=-=-___:__--_:__::_-'---_:_:____:__:___;.:***.:_--=*-=-=*-*--=--.!..:'-~-,.:..:.:*=====--_:_:_
~ *.
- tncr-ease at a* greater rate *. This 9reat.er rat! of te~~rature 1nd
* # pressu~e 1hc'l'"!ase fs maintained a~ the pres:surizer- fil1$ comp1iete1y !n~
weter-fs dischar9ed through the pressurizer re11ef ~nd ~Af~~~ ~atves. Rear;ti vi ty h~dback. due to the high primary system tem;:;-er~tute*> redu'=es cora power. As a result the system presur'! begins to deere<<~e and a steam space is a9ain formed fn the pressurizer. iht limiting criteria for the postu1ated transient3 ~s that reactor coolant pressu~e b~ maintained $Uff1c1ently below the pre~5Ul'.'e c~rT-esponding to the AS>£ Code Service i.eve1 C (£.mergenc)".) ~e~ss 1im1tG. For the ~ac~or coolant system, tne corres?ond~ng ~r-essure is 3200 p~ia.
- COHTR(X. R0Cfi4 lNOjCATIONS ANO MJT!GATING ACTIONS Although ~ie reactor is pr~vented from tripping 4Utomatic~11y ~Y the cor.:nor. ~de hOure c"f the reactor trip b'!"eakers, then: are ~any <:i)ntrGT room indications and a1anns wh1ch.4ra gene~atad dur1ni the tl'"ansient_
~hich would servi t~ al~r't the ope~ato~ that the event has tixan p1aee.
ihe~e ind1ca'tions in addition to ernergenc~ procedures, ,mfch rt~r.t~re tb.e ver1f1cation of a suc:essfu1 reactor trip befc~ all oth~~ dCt~ons, wouTci ~upport the mitigation of the consequences of the- transient.. F'o1" a 1os~ of narmal fe&dwaU.r event .. i" add1t1on to nol"'!l'ia1 precess
'gntro1 a1arms (pump trip, temperatu~~ p'l"'essure, level and f1~w deviat~on alanns for both primary ~nd $e<<:Ondary systems}. tn~ fnl1owtn~
-audible alarms ,.,,uld tle generated:
- l. Steam/feed~ater flow mismatch and low 1evet (each st~.!m generator}
- 2. Overtemoerature Ce l ta- T t.urbi ne l"'Unba~~
- 3. Qy~rtemp~rature Oelta-T reac~ar trip demand
- 4. Cv~l'))ower Del ta* T turb'f ne r\l~ac:k
- 5. Overpower- Del'ta-T reactor trip demand*
S.. High pressurii~r pressure nusc:tor6 trip demand 7 .. High pressurizer 1eve1 re actor trip demand
- 8. Steam generator l ow-1 ow 1eve l r-eactor trip demand
- 9. ~ow ~team pr-essu~ safety injection (in eo1nc1dence with nigh flow)
- 10. Lo-w r!actor coolant. loop flow reactor trip demand Tables l and 2 show the time . sequences for these alarm&- '
.As part of the procedures the opera to~ ts .requir~d to '!);~~; se following any reac-toi- trip demand, tne operator h required to first ~~rify the successful accomplistlnent of the reacto~ tr'ip by Ob$ervin9 rod position indicatorst rod bottom 11g~~s> neut~on flux, or reac'ttlr trip brgaker position ind1cat1ons. The following actions are available to the .. i.
operatcr in the main control. ~om if an unsuccessful l"'t'actor trip occurs: ii
- 1. Martu3l reactor trip (with subseq~ent automatic turbine tTiP.)
- z. Manua1 turt)ine trip J. Manual turb f ne runbac:k ( 200~/l:li n. )
- 4. M~nual safety injection 5.. flianual contro1 rod insertion *
- 39990 J
~-
"i
.... i Outside the obvious benefit o~'an inmedfat.e~reactor trip. th-e tur'.>ine
- trip or tu~ine runbact action is the most im-portant, if~ ~a;ctor trip canno~ be obtained manual1y~ to tenninate tbe steam flow den~n4 f.rom ~he steam generato~s to preserve steam generator inventory. Steam pre$$U"r"e
!nd hen'e primary s~stem temperaturt wf 1i be CQnt~11eo by means of tn~
~team dump controi system, steam generator relief and/o~ safety val~es.
Other medns out3ide .the main control rocm arc avai1ab1e:
- 1. L~a1 manual trip of any reactor trip b~aker
- 2. Local manual trip of "the rod cont?"'Ol system motar--gene~~tor sets
- 3. Local manua1 trip of the turbine TRANSlENT SlMUlATIOH
~na1yses ~~ performed to sirnu1~te both a pa~ia1 and ~~1et! 10$$ of '
miin feedwater. These analyses are based upon previous mo4el$ consistent with previous ~ubmittals to the HRC by Westinghou'e on ATiiS {MS-TK\-Z182y T. M* .bltde~on to Or. S. Hanauer, 12/30/79!' but .11so a~ mcdifie~ tc ~o~ accu~at.ely l')del the Sa1em Plant. ihe f(l110w1ng*eond~t.ions were a~s~-:sed for both analyses: 1.. In1t.ial nomai ful1 power cperetion at t:eginning of c;:)re Hfi!. ih~s c~rr.es"cnds to the current cond1t1on of the S<<1em rtant and is a1sc the 11m1t1n9 eor.dition since the i;;ogerator teizroeratuF;! coefficient is at it~ leut M9at~ve vaiue. A value of -a'ix:"m/*F. \ihicn*;s valid for 95i of core Hfe, was as~umed.
- z. Sot.~ the pressuriier relief and saf~ty valve$ i~~ as:~~ tn funtt-:cn. There are two ~lief and three safety 'fa1'1~s ..
Pr-e~3urfaer heaters and spray also function autcmaticany ..
~
J. The automatic turbine runbac:k on either Ovel"'temperatu~ OJ" Overpawr- :* Oe 1 ta- T si*gm1 l 5 f s operable *.* The runtJ4c); setpo i n t i s 3~ below ttre i' t~ip setpcint. The turbine runback operates on 1 30 seccnd cycle. Turbtne 1oad is first r-educed s: 1n LS sacancu. * !f .Ji. the end of 1 the 30 seconds the runbacx signal $'t11l exists,* the lozid ~~ further ; reduced another si and so on.
- The lQad reduction nas i .=;t;~atin9. t i
effect on the transient and helps r-educe peak primar:r system ,.t . pressure. t
.i
- 4. The rod c:ontrol system is assumed to be in the manual mode l consist.ant with aetua l praet1c:e. Autcmati c action a f the rod .*Lt c~n~rol system ft'OU}d cause rod in$ert1on when primar.' tam~eratur.t f ncreases and would be less conservat1ve. !
- 5. The* steam dump control system is avai1ab1e. The capa~ity of the s~eam dump is 5~ of nominal steam f1ow at full power.
- a. Auxiliary feedwater f1ow (1760 gpm) begin*s at io Se$;Q.ndS f'oHolrfng
~ceipt of t.ne low-low sie~m generato~ 1eve1 signa1. Tnis response time is based upon actual t~st data f'f"Om the Salem Plan~.
- 7. Operator action is assumed to initiate a succe~sful !lUlr..ual t?"ip.
Turbin~ ~rip 1s 1nitidted v1s the reaetor trip breaker o~ening *
........ -*~-- .... *- .. . .- -* . - ....
- .~
8* For the complete loss of feedwater tran$ient, the main feedlitater
- put!!ps are aslumed to coastdcwn to zero f1ow in five se-e~nds. For *
~
the *loss C!f i $ingle pump. one PLlnP is assumed* to caastdcnm 'to zero *'
- flow ~n five second~; howevert the remaining pump has ra~ed t1a~
C.!pa.eity of 7~ of" nominal full power feedwater flow. Therefore,. the se~ond pump {the Salem Plant has~ pumps) will 1nc~ase its flow tc 70: fiow. Th~ re$pOnse time for the second pump is.20 seeonds.
- 9 *. Notni nal -~ont:-t>1 and protection system setpoints were assumed.
TP.AHS!£NT RESULTS.
- 1. Loss of. a Ma 1n F~e~wat*~,. Pump The sequence of events for both a 30 sacond and 300 se-cond delay of isanua1 ~actor trip ar~ shown in Table 1. The transient prirnar.t pressu:-e i:alcu1 ations are shewn 1n F'1 gure L The low-lcw*i."team gener~tor level $etpoint is ~ached at 99 seconds; auxi1iary f~dwatar 1s autom.atica11Y- initiated. Ten second~* l~"tf!~, aux11iary fesdwater begin$ to be delivere<1 to tht! steam generatcrs4 30 s~cond Ot!i~
For the e~se where there is only ~ 30 $f!COnd delay, there ire no subsequent reactor trl p si gna1 s generat~d. There is no large heatta? of the reac:Ulr c01llant becau!.:e the stH:m generator tube bund1e doe$ _ not uncover. Thus there is a1ways adeQuate secondary s:ida beat removai. The peak pr~ssu~ ef ZZS6 psia which occurs 4t JO seccnd$> 1 s only slightly above. t."le presiure at which the presuriz~r sprays are actuated'. . *
- For this trans1Qnt. the reac~cr c:oa1ant system integri~y 1~ not challenged. * *
- S f.fi nute De l ay For the c:ase whel"'e operator act1on 1s delayed 300 seet>nd$ ( 5 minutes), the reactor ~col int system umperature in,r-:eases,, t't:!&ching the Overpalll'er Oelta-T setpoint. for turbine runt>ack at 190 seconds.
This signal is maintained and thus turbine power c;ontinves to redu~e 5~ every 30 seconds until the turbine .load is at 75~. At this
- point, the sUi-n of the ma1n feedwater flow h-ourone p~m;- plus tt'ie au~i1ia~ feedwater flow is equal to the turi)ine steam flO'tl.
Therefore. steam generator level does not cont1nue decraasfag and 5't4bili:es~ The operator 1n1tiatad re~cior and*turbine tr;p at J99 seconds occurs atur the steam and f eedwater fl ow have :natcned. The J)eak primar:r system P"SSU~ of 2330 ps'f a at 267 seconds accurs-bi!fore the steam and feed fl ow are matched. TM s pressure f s below the relief valve setpaint (2350 psia). The pressurizer sprays,
;gmt,ined with the effeet of reduced turbine load preYent. a~.
51 gni fie ant overpressuri :a ti on. ~gain*. rea,tor coo 1ant pr-es sure stays below $ervi c~ Level C 1i;;f t$ of 3200 psi a. . - s 3999Q
\
\
Z. Loss of A11 Main Feedwater
- The sequenca cf events foia this. tr~nsjgnt are presented tn iab le* 2.
The tran!1ent pressure ca1cu1ations are depicted 1n f~gur~ The low-iow steam generator 1~ve1 setpoint is reac:heD at 3.3 $eeonds~ 2.
'l
~
t 10 seconds *iater. aux1liury feedwater is de1ivere~ to the steem r generators. t
. -* L fI JO 'Seeori'd .Del av l
~
An autcma~ic turbine runba.cl *due to an Overpewer Oelta-T is i initiated at 43 seconds and turbine. 1oad f s reduced ~. ihe p~essurize~ fe11ef*Va1VC~. Open and maintain pressure at*the setpoiAt i l value {23501 unti 1 tne oper-ator tr1 p~ the plant 11t 63 seconds. { Steam dump f s initiated ana reduces tt>e pr1~a?7 tem;=:eratvre. to tn.? no load value of 547*F. Fo~ thii transient the rea~tor ~O<>~*nt. system p~ssu,-.: is well below 3200 psia. 5 Minute *~lay As in the previous case.* the heatti-p of the l)rimar-1 c~o hnt cau~e~ ~ turt>i n~ runb~c:t ~ nH. fa tefj by an Overpawer De 1t.a--T si -gna L The turbine 1cad is reduced twice in S~ inc~nts until the lead is 9~ of M=i nA l load. Steam pressure .$.t~rt~ to drop due tn th~ ooi 1 off of.. water in the ~tedlft- generators~ gener~t1 n9 a low ste= pressure
. al.am. A.t tM s time primary pressu'"i! iUrts to inc:re~s.~ a~ there is on insurge into the pressuriie~, ~*using bo"th pres~ur;,~r high
- 1eYel and pressure*trfp alarms to be actuated. The stsam genel'"atgr tube bundle begins *~c uncover, causi"9 a larger ~ate of increase in primary pressu~ and tempe~ature. ihe. pre~~urlzer fill$ .a~d tne peak pressur'1:! ~~ched is 3491 ps1a. Huclear power has dtM:reased ~t tn1s po1nt to a.bout 30'i of nominal due to t.~e negativ~ mode~atcr tempera~ur-e reactivi~y feedback *. As the ~lief ~ate of **ter t:trough the relief ind safety valves in~r-eases, the pr;mary -sys"t...~
pressure starts to d~reas~* and th-e !taf~ty and relief va1 ~s close-aoout3& s~oncss afteia 'dle time of peak pre~su~. The opes-ator trips the reactor manu~lly at 333 seconds. COHO.US IOMS The ~su1ts p~eser.~d here de~ns~rate that for th~ 1oss of o~ =a1n Tl!'!!dwat~r puap, the~ ar~ at l~.ast si.,; ma.jar i!lan1s 1n 4d4~ti.a-n to ottier~* generated to alert t~~ ~perator to the fact that ~ m~1func:tion ha~ occun!d.. Furthermora. @ven for t."i~ eYent witn a five tDinut:~ dela,,v 1n ~.actor "trip automatit; turbine MJnbac.k reduces st.ea~ f1ow to mtch the capabfHtjr of the auxiliary f~dwater. F'os- this even-~ ~~ts tta threat of o~erpressurizat1on in that the pressuri:e~ relief yalve
- setpoint* ts *not !ven reached.
6 39990 '*
i Como1 ete lo~s of Main F'e~dwater. f l 1 For th~ comp1ete 1oss of feed~ater, operator action ccnsi~tan~ ~1th the: action time taken at the pl ant on the Februaey 25, 1983 ev~n't ts sufficient to prevent ove1'1)ressuri:ation of the reactor ~oo1ant system. I Peak primary system pressure results only tn pr~s!urizer relief valve actuation without the actuation* of pressurizer sa.fJty valves. l' FurtheJ"m1)re. there ar~ 3 major .a-1an:s$ which are actuated fn ..i~ition ti>* the steam generated 1ow-1aw level a1ann to alert the operatDr tD take action. -. * , \ t
~
t.- As discussed earlier. 1t. ts a majo~ reduction 1n-pr~~ar;t
- heat t:rans f~r capabi 11 ty wM ch cau&es the primary system h:-.atup and tn seeanda~ t::
pres sure i nere ase.. A 'f;urbi ne trip reduces the arnount of ~us 11 ow and ~
~
the rate at which the leve-1' in the steam generator drops. 1f ~e turb1ne is tripp~ before the~ is i significan't las' of stem 911nerator '""
~
"i:
invento~. the tubes will not uncover and the pnmary syste= wi11 net " overpr'!ssuri ze. Based upon the rt!Ults discus-sad in the prtYious - - .j
~
s*ct1on. operator action to trip tha turbine at or- befar-e one to one and i a half minuus following the 1ow.low level trip and a1anA .ould prevent ! overpressuri :ut1 on of the reictor coo hnt syst&D btro-ttd 3200 psi a.
~
Ii lt sho~1d be noted that the core nucle1r characteristi~s (a 1110derato~ l reac'tiv1 ty coeffic'f eirt of -8 rx:m/*r) used are not tef)re.sentat~'f1! of the *v actual c~ design for- the Salem P1ant. Previous AntS 4nai1~~$ nave shown the peak pressure ta be ~ stron9 func:tion of the CDetfie~~ftt and i i
*there ~s & 100 psi redlJct~on fo~ ever:t l pt;:t d.e~e~se fn the ~
t:1)eff1ehnt. The Sa 1em core is desi ~d tt> opar-ate 5uc:h th~t by tn~ '1! 1'
~
time the plant reached full powe~ 1t would have a coefficient of -10.s *ft
~m/*f' or 2.S p~'lll less *tjnm th@ c:ceff1c:1ent fn the study .. This .
eoeffi~ient would be reduced even further ~Y appT"ClximQte~y Z pcs1*F per :.
~
i* rionth o1 oparation f~ee F1gur~ 3)._ ibe 10.5 ~cm coeffi~ient ~sults in a peat pressure for the l"lm1t1 ng cas~ of f1 ve minute Ol)t!l"_a1:0r .action of 3241 ?Si a (a 250 psi a reduc:ti on -from 3491 psi a} ~1 ~h 1 s 'ff1 thin the .
..It
- caiculat1ona1 band of the ASJ.£ Stress LeYe1 C 11m1t. Tl:erefc~,. ttie ~
case ~pr-esent2d 1n Figure 2 would not exceed thtt acesJ)tarn:~ ai teri a.. ?
~
Su=nary l'I
~
I I~ eonc:1u$1on, ttli~ $tudy has desi:ionstrated the ability of the Silem I., jUelear p1ant to withstand th~ effects of postulated ~$$ fe~fjw&ter
=al functions without reactor triJ) at full ;>a.el"' w1 ~ an ~rtiff-:'f41ly l
long* delay for operator action. The re!ults snow ac~~t)t3!>le reS?onse *
~
wbicn is within cal~ulationa1 uncertainties Qf the AS1'£ Stre-ss Level C i1 s. Hta1t-s. These r11sults*are further &ffect*d by the low 9robabllity of . i these e:v~nts ()j;Cur1 ng 1t full power in addition to the exr:t~ted i 1nc:nastngly beneficial nuclear characteristics of tJte plant over eore i' t Hfe. ! ti
.*i i
- 399~Q 7 .
- I
~ -
I
. . .* - - ........ ___*_*~~*-_--_-_._*__,_._-_-_*-~*
.. _.-_.-'---'-=~.:.-=-*-__;_*~:"""'r."'-'--'-'. *~:___
-"-::--::___,. _ _ _ _ : _ _ , _ _ ; *_ ___;*_~
----~
-:;-* E
- TABLE 1 I*
I* Se_quence of Events .. Less of One FeedWater- Pump l
.... -Event Loss of one ~ump {4lan"D)
-nme1 0
TiQ!2 JJ Ire Ra~ining pi.mip de 1i Vf!rs max 1mum f 1~w 20 i. 20 i};: Low-low SG level setpoint {alarm); *~
"'t au~iliary feedwater signa1 (a1arm) 99 99 ~-
t* 109 Auxiliar,y feedwater begins OperatQr tr1ps reacior and turbine 109
--- i O? AT runb~ck setpcint (al~"8) i29 i.,
~
~
190 turbine load reduced 5~ *- 233 I! iurt:ine load reduced S: -- .* OP ~ T" trip setpoi nt .(al arm) --- zzo :I Turbine 1oad reduced 5~ -- zso l~ Z67 {l~SO psia} .i Pe.ax Pressure ();i:urs ..-- Turtli n~ 7oad reduced 5% --- 2SO li l!; Turbine 1oad reduced 5~ 310 ~ High pressurizer level setpoint {alarm} 31-1 i:;
..... ~
Operator trips N!actor and turbine 399 t i
~
3 alarms
- 6 alarm~ f prior- to pr'iar to "'i tr1p trip 1 ...
i
~
(1} 30. s~cnd . de 1tI.'I beftire manua 1 tr1 .D l
~
j (2) 30.0 secand delay before manual trip
.~
a 3999Q
* -~ *-~--*- *-~------ __ .. -~---- .... *--* *-----**~- . * **-:-***-~,.~~~:-- .* --:.** __ .. __ *::a--- . *--*-
TABl.E 2
- Event S!quence of Events Complete l.oss of lifain Fe*edwater Loss of main feedwate,. pumps (alann} 0 low-1ow*SG 1eve1 setpafnt (alar:=);
auxiliary fee'dw~ter .iignal generation 33 l3
°" b T runDacx se tpc;i nt (al arm) 34 turbine load reduced 51 OP~ T trip setpoint (alaJ"'ll) 43 Auxiliary fe!'dwater begins 43 43 Pressurizer reH!!t' valves. open 55 55
* *O?eJ"atoi- trips. reactor/turbine oJ Tur'Ji ne *load reduct!d 51 -- 54 Hf gh pressurizer 1eve1 trip setpaint (a1ania} --- .as Lew staam pn!ssure SI {aianD) .SS High pressu,.izer pressure setpaint (alarm) *** 88 SG tubes 0egi n to uncover; *
~team new drap$
pressurizer safet¥ va 1ves open Pressurizer fi11 s
*- 92.
.95 Peak pre-ssurt ll4 (3491 psia)
Pressurizer safety.valves close Pressuri4er relief valves close
*----* l4t .
155* Low RC f1ow $etpo1n~ (alarm)
-Operator tr1 ps reactor/turbine
-- Ji!
3:33 4 alarms 1 alarms prior- to prior to trip trl-p (1) 30 second delay before raanua1 trip C2} 300 se-:cnd de 1ay befo-re manual tr. p g
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- In the Matter of PUBLIC SERVICE ELECTRIC UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION
)
)
) Docket Nos. 50-272 and 50-311 AND GAS COMPANY ) License Nos. *DPR-70 and DRP-75
)
(Salem Nuclear Generating ) Station, Units 1 &.2) ) ORDER MODIFYING LICENSE EFFECTIVE IMMEDIATELY I. Public Service Electric and Gas Company (the licensee) holds License Nos. DPR-70 and DPR-75 which authorize operation of Units 1 and 2 of the Salem Nuclear Gen-erating Station. The facilities are Westinghouse pressurized water reactors (PWRs) located at the licensee's site at Hancock's Bridge, Salem County, New Jersey. II. On February 25, 1983, an event occurred at Unit 1 of the Salem Nuclear Generat-ing Station when the control rods failed to insert when the reactor-trip circuit
*breakers failed to _automatically open following receipt of a valid trip signal from the Reactor Protection System (RPS). The manual trip system was used to shut down the reactor. Subsequently, it was concluded by the licensee that the failure to trip was caused by a malfunction of the undervoltage (UV) trip attachments in both reactor-trip circuit breakers. Evaluation ~! the event of February 25, 1983 revealed that a similar failure had occurred on February 22,
- I
- 1983, at Salem 1. There had also been a previous event a~ Salem 2 involving a failure of one reactor trip circuit breaker to trip on January 6, 1983.
The malfunction of the unde_rvoltage device on February 25 was determined by the licensee to have resulted from lack of proper lubrication on the latch of the UV trip attachment. It appears that no preventative maintenance had been con-ducted on the Salem 1 DB-50 circuit breakers until January 1983. Additionally, the recommendati-0ns of a Westinghouse 1974 Technical Bulletin a~d Da~~ *cetter (NSD DATA LETTER 74-2) were not implemented during the January maintenance since the personnel who performed the maintenance were not aware of the bulletin re-commendations. The specific details of the event and the licensee 1 s response are contained in the staff s Safety Evaluation Report, which is hereby incor-1 porated by reference. The NRC review of the event revealed a number of significant deficiencies relating to management supervision and control of the procedures governing the classification of the reactor trip breakers as safety-related, management super-vision of maintenance techniques, and management attention to the safety impli-cations of system malfunctions. This review is set fo~th in NUREG-0977, 11 NRC Fact-Finding Task Force Report on the ATWS Events at Salem Nuclear Generating Station. Unit 1, on February 22 and 25, 1983, 11 March 1983, which is hereby incorporated by reference. If there were a potentially severe transient, from a worst case set of initial conditions, and the reactor shutdown system did not function, an extremely severe accident could occur in the absence of timely operator action. Therefore,
the aforementioned failures are technically very significant. When coupled with the cause of the challenge to the reactor protection system, i.e., a feedwater system transient, and the frequency of past feedwater system transients 1 at the Salem facilities, the event raises serious safety questions regarding the continued safe operation of the Salem facility .
. III.
Analysis of the event described in Section II reveals operational and manage-ment issues at the Salem facilities which are discussed in the staff's Safety Evaluation Report. By letters dated March 14, April 4, April 7, and April 8, 1983, the licensee submitted its Corrective Action Program related to the reactor trip breaker failures. This program includes short-term remedial actions to be completed prior to startup of the unit and a number of longer term items which have not been completed but for which the licensee has established completion dates. 11 These items are summarized in the attached Table, PSE&G Corrective Action Report, Short and Long Term Items. 11 (Attachment 1) The various remedial actions involve equipment, operational and management issues. The equipment issues involve (1) safety classification of breakers, 1 0f primary concern t~ the NRC is the ATWS (anticipated transient withou~ scram) event initiated by a loss of feedwater transient. In 1981 and 1982, Salem 1 experienced about 11 and 5 feedwater transients, respectively, while Salem 2 experienced about 14 in 1981 and about 11 in 19B2 .. This results in ~n average of about 10 transients per unit year of operation for each unit.
- (2) identification of cause of failure, (3) verification tenance and surveillance procedures.
~esting and (4) main-The operational i.ssues involve (1) operat-ing procedure for reactor trips and anticipated transients without scram (ATWS),
(2) operator training, and (3) operator response. The management issues involve (1) master equipment 1 i st, (2) p~rocurement procedures, (3) work-order procedures, (4) post-trip review, (5) timeliness of event notification, (6) updating vendor-supplied information, (7) involvement of QA personnel with other station depart~ ments, (8) post-maintenance operability testing and (9) overall management capability and performance. The NRC staff has reviewed the corrective action program as discussed in the staff's Safety Evaluation Report, and determined that the licensee's actions, as modified below, are necessary to assure con-tinued safe operation of the facility. In addition, I have determined that because of the history of the Salem facility described above, the need for further long-term actions to increase the reliability of the mitigation features of the Salem facility must also be addressed. Accordingly, I have determined that the public health, safety, and interest require that the actions set forth below be required by an immediately effective order. IV. In view of the foregoing, pursuant to Sections 103 and 161(i) of .the Atomic Energy Act of 1954, as amended, and the Commission's regulations in 10 CFR
- Parts 2 and 50, IT IS HEREBY ORDERED EFFECTIVE IMMEDIATELY THAT:
- 1. The licensee shall implement and/or rr.aintain the items specified in Attachment 1 to this Order, as more fully described and in the manner described in the licensee 1 s submittals dated March 14, April 4, and April 7, and 8, 1983, no later than the dates specified in Attachment 1, with the following modifications:
(a) The Nuclear Oversight Committee shall, in addition ta the actions described in the licensee 1 s.April 7 and 8, 1983 submittals, provide copies of its reports to the Executive-Vice President and to the NRC Regional Administrator at the same time they are submitted to the Vice President-Nuclear. (b) Within 60 days of receipt of the appraisal performed by Manage-ment Analysis Company (MAC), the licensee shall provide t.o the Director of the Office of Nuclear Reactor Regulation, an analysis of each recommendation made _by MAC, the action to be taken in response to each, and a schedule for implementation. (c) Prior to return to power, engage Beta Corporation, an outside consultant, to review the PSE&G investigation of the events of February 22 and 25, 1983, including the corrective action program. The consultant will make*an independent evaluation of the action plan and advise on the adequacy of the program to insure that Salem Unit 1 can be safely returned to power.
-----------------~ -------- - - * - - - - - -
- 2. Within 60 days of the date of this Order, the licensee shall submit to the Director, Office of Nuclear Reactor Regulation a detailed report describing either how and on what schedule the following actions will be accomplished, or why any of these actions should not be taken.
(a) Implementing at the Salem facility (Units 1 and 2) the following feature of the proposal by the Industry Group on ATWS submitted on April 23, 1982, on Docket PRM-50-29 (page 10 of Appendix C): provision of automatic initiation of turbine trip and auxiliary feedwater independent of the reactor protection system; (b) Providing at the Salem facility diversity in activating (tripping) the reactor scram breakers, for example, by incorporating the breaker shunt trip function into the automatic trip circuits of the reactor protection system; Any schedule submitted shall be subject to approval by the Director and shall be implemented following such approval. The Director may modify the approved schedule in writing for good cause. v. The Licensee may request a hearing on this Order. Any request fo_r a hearing shall be submitted to the Director, Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, D."C. 20555. A copy of the
- request-or answer shall also be sent to the Executive Legal Director at the
same address. ANY REQUEST FOR A HEARING SHALL NOT STAY THt IMMEDIATE EFFECTIVENESS OF THIS ORDER. If a hearing is held on this Order, the Commission will issue an order designat-ing the*time and place of hearing. If a hearing is held, the issue to be con-sidered at such a hearing shall be whether this Order should be sustained. FOR THE NUCLEAR EGULATORY COMMISSION: Harold R. Denton, Director Office of Nuclear Reactor Regulation Dated at Bethesda, Maryland
- this day of April 1983 .
ATTACHMENT 1 PSE&G CORRECTIVE ACTION REPORT SHORT AND LONG TERM ITEMS ITEM COMPLETION A. EQUIPMENT ISSUES A.l Determination of Safety Classification of Breakers Comp Tete* A.2 Identification of Cause of Failure
- a. Short-Term Actions
- 1. . Confirm that new U/V trip attachments Complete on Salem Units 1 & 2 incorporate all design changes made to these devices.
- 2. Measure and confirm the force required. Complete to trip the breakers using the breaker trip bar and that the breakers trip with an output force from the U/V trip lever of <31 ounces.
- b. Long-Term Actions
- 1. Submit a test program to determine the.
life cycle & replacement interval for the UTAs & to verify the adequacy of the new* maintenance & surveillance programs used on the reactor trip circuit breakers May 1983
- 2. Establish a procedure for periodically Complete measuring the force required to trip the breakers.
A.3 Verification Testing Program
- a. Short-Term Actions
- 1. Manufacturer will electrically test U/V trip attachment on Test CB 25 times. Complete
- 2. After installation, U/V trip attachment tested 10 times. Complete
ITEM .. COMPLETION
- 3. After installation in appropriate breaker compartment, Response Time Test. Complete
- 4. Test for independent operation of UV and shunt within 24 hours of restart*
from each shutdown. Complete
- b. Long-Term Actions *
- 1. Provide detailed test program May, 1983 A.4 Maintenance and Surveillance Procedures
- a. Short-Term Actions*
- 1. Resolve breaker cabinet/switchgear room cleaning deficiency. Complete
- 2. Revise maintenance procedure and/or other documents to require all replacement U/V attachments to have been successfully tested 25 consecutive cycles. Complete
- 3. Provide acceptance criteria in Maintenance.Procedure M3Q-2 for ten cycle test that allows NO failures for acceptance. There will"ti'e a 30-minute interval between each test. Complete
- 4. Modify Maintenance .procedure M3Q-2, Section 9.8 to include three timing tests and an average time computed for comparison to previous tests.* Complete
- 5. Revise Maintenance Procedure M3Q-2, Section 9.7 & other appropriate procedures *to require that a sealant be applied to the head of the self-locking screw on the U/V attachment. Complete
- 6. Specify in Maintenance Procedure M3Q-2, Enclosure 7 (Ref. Section 9.7) U/V coil dropout voltage acceptance tolerance &
actions to be taken if out of specification.* Complete
- 7. Lubricate the circuit breakers and UV trip attachments in accordance with WTechnical Manual.* Complete
- See attached Table 1.
ITEM . COMPLETION
- 8. Perform a trip force measurement on the trip bar of each breaker.* Complete
- 9. Modify maintenance procedure to test bypass breakers every 6 months.* Complete
- 10. Provide functional test procedures for UV trip, shunt trip, and manual scram.* Complete*
- 11. Perform monthly reactor trip breaker timing test.* Complete
- b. Long-Term Actions
- 1. Propose Technical Specifications Within 30 days of Unit S/U B. OPERATOR PROCEDURES, TRAINING, AND RESPONSE B.l Operating Procedures for ATWS
- a. . Short-Term Actions
- 1. Identify indications in control room providing positive identifi-
~ation of reactor trip demand. Complete
- 2. Review the basis for ATWS procedure steps and order of priority, revise procedures, as necessary, and train operators. Complete
- b. Long-Term Actions
- 1. Provide detail description of procedures to ens*ure operability of SSPS status
- panel indicators. Complete
- 2. Provide schedule for the upgrade program for Emergency Operating Procedures *April 15, 1983 8.2 Operator Training
- a. Short-Term Action
- 1. Conduct training for operators on revised procedures . Complete
- 2. Conduct practical exercise in Control Room of revised procedures. April 12, 1983
*See attached Table 1.
- ITEM 3.
4. Conduct walkthrough on alarms & RPS indicators. Conduct training for auxilary operators
. COMPLETION April 12, 1983 April 12, 1983
- 5. Evaluate trainees* performance against established objectives Complete
- 6. Review training material and ensure it is current and properly referenced Complete B.3 Operator Response
- a. Short-Term Action
- 1. Caution operators in use of J handle control. Complete
- b. Long-Term Actions
- 1. Replace Reactor Trip Switch Next outage of sufficient duration
- C.
- 2. Modifications to clarify First Out Annunicator Alarms MANAGEMENT CAPABILITY AND PERFORMANCE May 1, 1983 C.l Master Equipment List (MEL)
- a. Short-Term Actions
- 1. Verify MEL is complete & accurate.with respect to ECCS, including actuation systems, RPS, Aux. Feedwater_and containment isolation systems. Complete
- 2. Instruct appropriate personnel in purpose & use of MEL. - Complete
*£~*
- b. Long-Term Actions
- 1. Verify completeness & accuracy of MEL for remaining Q list systems -and re-issue as a controlled document . May 1983
ITEM .. COMPLETION C.2 Procurement Procedures
- a. Short-Term Actions
- 1. PSE&G Sampling review of past procure-ment documents Complete
- b. Long-Term Actions
- 1. Evaluate & modify procurement procedures to ensure appropriate classification of items/services important to safety. Ju1y* 19s3 C.3 Work Order Procedures
- a. Short-Term Actions
- 1. QA Department review all nonsafety-related work orders prior to starting work. Complete
- 2. Implement a program & training to ensure that work orders are properly classified. Complete
- 3. Review work orders written since issuance of the MEL for proper classification & evaluate safety consequences of those found improperly classified. Complete C.4 Post-Trip Review
- a. Short-Term Actions
- 1. Develop and implement AD-16 Complete C.5 Timeliness of Event Notification
- a. Short-Term Actions
- 1. Assign dedicated communicator to each Complete shift.
- 2. Review importance of reporting require-ments with supervisors Complete
ITEM COMPLETION C.6 Updating Vendor-Supplied Information
- a. Short-Term Actions
- 1. Update existing documentation on safety equipment and ensure that vendor docu-mentation is under a controlled system.
a) Audit Station files for manuals existence, revision level, and date. Complete b) Audit Nuclear Engineering files for manuals existence, revision level, and date. Complete c) Compare Station & Nuclear Engineer-ing; Audit and use lastest manual revision Complete d) - Contact vendors to confirm that manuals are technically current Complete Request updated copies (~where identified as more recent)
- 2. Review Westinghouse Technical Bulletins and Data Letters Complete
- b. Long-Term Actions a) Audit Station files for manuals existence, revision level, & date June 1983 b) Audit Nuclear Engineering files for manuals existence, revision level, and date. July 1983 c) Compare Station & Nuclear Engineer-ing; ~udit and use lastest manual revision Aug. 1983 d) - Contact vendors to confirm that manuals are technically current Dec. 1983 Request updated copies (*where identified as more recent) e) Revise Station procedures where appropriate July 1983
ITEM
- COMPLETION f) Index & control new/revised manuals received May 1983 g) Develop procedures for controlling vendor manuals May 1983 C.7 Involvement of Quality Assurance Personnel With Other Departments
- a. Short-Term Actions
- 1. Retain outside consultant to assess QA program Complete
- 2. Modify QA organization policy to more fully integrate with.overall nuclear activities Complete
- b. Long~Term Actions
- 1. Provide additional detail training on processing work orders to re-emphasize QA test/retest requirements September 1983 C.8 Post Maintenance Operability Testing
- a. Long-Term Actions
- 1. Review and revise AP-9 and other station procedures July 1983
- 2. Complete review of vendor and Engineering recommendations and incorporate necessary changes into departmental documents Janua_ry 1984
- 3. Incorporate items identified into Inspection _Order System Aug. 1983
- 4. Complete Managed Maintenance Program Jan. 1984 C.9 Overall Management Capability & Performance Complete staffing of Nuclear 1.
Assurance & Regulation Department Jan. 1984
- 2. Independent assessment of QA
- Operations July 1, 1983
ITEM COMPLETION
- 3. Implement training program for first-level supervisors Sept. 1983
- 4. Develop training program for senior supervisory level Oct. 1983
- 5. Develop program for periodic or regular training for supervisory a~d managment personnel Spring 1984
- 6. Develop Technical Training Program for non-Station personnel -spri hg 1.984
- 7. MAC management diagnostic -
final report May 30, 1983
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