ML18004B912: Difference between revisions

From kanterella
Jump to navigation Jump to search
(Created page by program invented by StriderTol)
 
(Created page by program invented by StriderTol)
 
(One intermediate revision by the same user not shown)
Line 3: Line 3:
| issue date = 08/20/1987
| issue date = 08/20/1987
| title = LER 87-046-00:on 870722,main Feedwater Pump B Tripped Due to Low Flow Resulting in Automatic Start of Auxiliary Feedwater Pumps.Caused by Loose Linkage on Recirculation Valve Due to Vibration.Valve Repaired.Procedures changed.W/870820 Ltr
| title = LER 87-046-00:on 870722,main Feedwater Pump B Tripped Due to Low Flow Resulting in Automatic Start of Auxiliary Feedwater Pumps.Caused by Loose Linkage on Recirculation Valve Due to Vibration.Valve Repaired.Procedures changed.W/870820 Ltr
| author name = SCHWABENBAUER, WATSON R A
| author name = Schwabenbauer, Watson R
| author affiliation = CAROLINA POWER & LIGHT CO.
| author affiliation = CAROLINA POWER & LIGHT CO.
| addressee name =  
| addressee name =  
Line 16: Line 16:


=Text=
=Text=
{{#Wiki_filter:R JL RY INFORMATION DISTR 1 TI.SYSTEM (RIDS)ACCESSION NBR: 870IT'030005 DOC.DATE: 87/08/20 NOTARIZED:
{{#Wiki_filter:R   JL     RY INFORMATION DISTR     1   TI . SYSTEM   (RIDS)
NO FACIL: 50-400 Shearon Harris Nuclear Poujer Planti Unit 1I Carolina AUTH.NAME AUTHOR AFFILIATION SCHWABENBAUER Carolina Poujer 8i Light Co.WATSONI R.A.Carolina Poujer 8.Light Co.RECIP.NAME RECIPIENT AFFILIATION DOCKET 05000400
ACCESSION NBR: 870IT'030005         DOC. DATE:   87/08/20     NOTARIZED: NO             DOCKET FACIL: 50-400 Shearon Harris Nuclear Poujer Planti Unit 1I Carolina                   05000400 AUTH. NAME           AUTHOR AFFILIATION SCHWABENBAUER         Carolina   Poujer 8i Light Co.
WATSONI R. A.         Carolina   Poujer 8. Light Co.
RECIP. NAME           RECIPIENT AFFILIATION


==SUBJECT:==
==SUBJECT:==
LER 87-046-00:
LER   87-046-00:   on 870722I main   feedujater   pump B   tripped due to low   floe resulting in automatic start of auxiliary feedujater pumps. Caused bg loose linkage on recirculation valve due to vibration. Valve repaired. Procedures changed. W/870820 ltr.
on 870722I main feedujater pump B tripped due to low floe resulting in automatic start of auxiliary feedujater pumps.Caused bg loose linkage on recirculation valve due to vibration.
DISTRIBUTION CODE: IEEED COPIES RECEIVED:LTR               f TITLE: 50. 73 Licensee Event Report <LER)I Incident Apt> etc.
Valve repaired.Procedures changed.W/870820 ltr.DISTRIBUTION CODE: IEEED COPIES RECEIVED:LTR f ENCL Q SIZE: TITLE: 50.73 Licensee Event Report<LER)I Incident Apt>etc.NOTES: Ap'plication for permit reneuJal filed.05000400 REC IP IENT ID CODE/NAME PD2-1 LA BUCKLEYr B INTERNAL: ACRS MI CHELSQN AEQD/DQA AEOD/DSP/ROAB DEDRO NRR/DEST/CEB NRR/DEST/I CSB NRR/DEST/MTB NRR/DEST/RSB NRR/DLPG/HFB NRR/DQEA/EAB N-/RPB ILE 02 DI J RQN2 FILE 01 EXTERNAL: EQ~oG GROHI M LPDR NSIC HARRISI J COP IES LTTR ENCL 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 1 1 1 1 5 5 1 1 1 1 RECIPIENT ID CODE/NAME-PD2-1 PD ACRS MQELLER AEOD/DSP/NAS AEOD/DSP/TPAB NRR/DEST/ADS NRR/DEST/ELB NRR/DEST/MEB NRR/DEBT/PSB NRR/DEST/SGB NRR/DLPG/GAB NRR/DREP/RAB NRR/PMAS/ILRB RES DEPY QI RES/DE/EIB H ST LOBBY WARD NRC PDR NSIC MAYBe G COPIES LTTR ENCL 1 1 2 2 1 1 1 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 TOTAL NUMBER OF COPIES REQUIRED: LTTR 43 ENCL 42  
ENCL Q SIZE:
~0 NRC Form 388 (8.83)LICENSEE EVENT REPORT (LER)U.S.NUCLEAR REGULATORY COMMISSION APPROVED 0MB NO.3)604104 EXPIRES: S/31/88 FACILITY NAME (II SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 DOCKET NUMBER (2)IIAGE 3 0 5 0 0 0 400 10FP 3 ("MAIN FEEDWATER RECIRCULATION FLOW CONTROL VALVE FAILED RESULTING IN A MAIN FEEDWATER PUMP'B'RIP ON LOW FLOW ACTUATING AUXILIARY FEEDWATER SYSTEM EVENT DATE (5)LER NUMBER (8)REPORT DATE (7)OTHER FACILITIES INVOLVED (8)MONTH OAY YEAR YEAR Er ry SEOUENTIAL NUMBER MONTH'&A NUMBER DAY YEAR FACILITY NAMES DOCKET NUMBER(S)0 5 0 0 0 0 7 2 28 787 0 4 6 0 0 0 8 2 0 8 7 0 5 0 0.0 OPEAATINQ MODE (8)POWER LEVEL p p 20A02(B)20.405(el(1)
NOTES: Ap'plication for permit reneuJal filed.                                         05000400 REC IP IENT         COP  IES            RECIPIENT            COPIES ID CODE/NAME          LTTR ENCL        ID CODE/NAME           LTTR ENCL PD2-1 LA                   1      1    -PD2-1 PD                  1    1 BUCKLEYr B                 1      1 INTERNAL: ACRS MICHELSQN              1      1      ACRS MQELLER              2    2 AEQD/DQA                   1      1      AEOD/DSP/NAS                    1 AEOD/DSP/ROAB                             AEOD/DSP/TPAB                  1 DEDRO                       1            NRR/DEST/ADS              1    0 NRR/DEST/CEB                1      1      NRR/DEST/ELB              1 NRR/DEST/ I CSB            1      1      NRR/DEST/MEB NRR/DEST/MTB                      1     NRR/DEBT/PSB              1    1 NRR/DEST/RSB                      1      NRR/DEST/SGB                    1 NRR/DLPG/HFB                1      1      NRR/DLPG/GAB              1    1 NRR/DQEA/EAB                1      1      NRR/DREP/RAB             1    1 N    -    /RPB          2      2      NRR/PMAS/ ILRB                 1 ILE        02              1      RES DEPY QI                     1 DI J                1      RES/DE/EIB               1    1 RQN2      FILE    01      1      1 EXTERNAL:  EQ~oG  GROHI M            5      5      H ST LOBBY WARD           1     1 LPDR                        1     1     NRC PDR                  1     1 NSIC HARRISI J              1     1     NSIC MAYBe G                    1 TOTAL NUMBER OF COPIES REQUIRED:           LTTR   43   ENCL     42
(0.20A05(e)(1)(EI 20.405(el(1)(lll) 20AOS(e)ll)(lv)20.405(~)(1)(v)20.405(c)'0.38(c)0)50.38(cl (2)50.73(e)(2l(I)50.73(e)(2)III)50,73(e)(2)Bll)LICENSEE CONTACT FOR THIS LER (12I 50.73(el(20(v) 50.73(e)(21(vl 50.73(el(2)(vS)50.73(~)(2)(vill)(A) 50.73(~)(2l(vill)(BI 50,73(e)(2)(e)THIS REPORT IS SUBMITTED PUASUANT-T 0 THE REOUIREMENTS OF 10 CFR ()r (Check one or more of the folloryinpl (11 73.71(II)73.71(cl OTHER (Specify In Ahrtrect INIorNend In Teer, HRC Form 366A)NAME R.SCHWABENBAUER
-REGULATORY COMPLIANCE TELEPHONE NUMBER AREA CODE 9 193 62-26 69 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)CAUSE SYSTEM COMPONENT B S J F C MANUFA(r TURER M 2 0 EPORTABLE)8)CAUSE TO NPAOS SL<rC.r..:..rO....
SYSTEM COMPONENT MANUFACr TURER EPORTABLE TO NPRDS 0'"~@3..: SUPPLEMENTAL REPORT EXPECTED (14)YES Ilf yer, complete EXPECTED sU64IISSIOH DATE)X NO ABSTRACT (Limit to I400 rpecet, Ie., epprorrlmerery fifteen elnpre rpete tyPervrltren lintel (18)ABSTRACT EXPECTED SU 8 MISSION DATE (I SI MONTH OAY YEAR The plant was operating at 1 percent reactor power in Mode 2, Plant Start-up, on July 22, 1987.Only one Main Feedwater Pump,'B', was in service.'B'ain Feedwater Pump tripped on low-flow which caused the automatic start, as, required, of both motor driven Auxiliary Feedwater Pumps.The Auxiliary Feedwater Pumps started and ran as required to supply~ater to the steam generators.
Plant temperature and pressure remained stable at normal no load values.An operator subsequently started the'A'ain Feedwater Pump and secured the Auxiliary Feedwater Pumps.The cause of the low flow was investigated.
The Feedback linkage on the'B'eedwater Pump recirculation valve was found loose.This prevented the actuator from receiving a signal to open and caused the low flow condition for the'B'eedwater Pump.O OE2 a (x)o Ron.OO h (T)(X)O (A~OV OQ OQ 07<O O(): (x)a.(f)The root cause of the failure was vibration of the valve.The loose linkage on the Feed pump Recirculation valve was repaired.A plant maintenance checklist has been developed to monitor the recirculation valve Feedback linkages monthly to prevent a recurrence of this failure.A Plant Change Request was also generated to investigate and resolve the high vibration experienced by the recirculation valve.reRC Form 388 The event is reportable per 10CFR50.73 (a)(2)(iv) as an automatic actuation of u F ture Auxiliar Feedwater S stem).
NRC Form 366A (94LI)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION U.S.NUCLEAR REGULATORY COMMISSION APPROVEO OMB NO.3150M)04 EXP)RES/8/3 I/88 FACILITY NAME (11 SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 OOCKET NUMBER (2)YEAR LER NUMBER (6)$,/i SEQUENTIAL OLRI NUMBER REVISION NUMBER PAGE (31 TEXT///more Eoeoe)I/))rrBed, Iree ddlobnsl HRC Frnn 3$!143)(17)0 5 0 0 0 40 08 046 00 02 oF 0 DESCRIPTION:
The plant was operating at 1 percent reactor power in Mode 2, Plant Start-up, on July 22, 1987.Only one Main Feedwater Pump,'B', (EIIS:SJ)was in service at the time.A pump low-flow alarm was received in the Main Control Room and an auxiliary operator was dispatched to check the position of the recirculation valve, 1FW-39.(Masoneilan Valve 6 Actuator Model Number 37-40412-8A-6)..
-The'valve was reported to be approximately 50 percent open.At 0500 hours'B'ain Feedwater Pump tripped due to low flow.Both motor driven Auxiliary Feedwater Pumps (EIIS:BA)started as requi'red to supply water to the steam generators.
Reactor Coolant System (EIIS:AB)temperature and pressure,-
and Steam Generator (EIIS:SB)water levels remained stable at normal no load values.An operator subsequently started the'A'ain Feedwater Pump at 0534 hours.and secured the Auxiliary Feedwater Pumps.CAUSE't was first thought the pump tripped on instantaneous overcurrent as the flag on'C'hase for'B'ain Feedwater Pump was down.Electricians checked the breaker and found no indications of an electrical fault.It was concluded that the flag was caused by the vibration when the breaker tripped.The cause of the pump trip was the low flow trip of the'B'ain Feedwater Pump.The low flow resulted when the pump's recirculation valve did not respond to the signal to open.Instrument and Control technicians checked the'B'ain Feedwater Pump recirculation valve and found a loose feedback linkage which kept the actuator from opening the valve.As a result, the recirculation flow decreased below the pump's low flow trip setpoint.The linkage was repaired and the pump started and ran normally.It was concluded that vibration of the valve caused the loosening of the linkage.The high vibration is caused by t.he thruttling action of the valve.The differential pressure across the valve is approximately 1700 psi.The vibration in the recirculation valve line has caused several failures in the operation of the recirculation valve.A broken linkage was first identified during power ascension testing where the recirculation valve would not shut.Prior to another event (reported in LER 87-005-00), the air line to the valve actuator had broken off and failed the valve to the full open position.NRC FORM 3BBA rrr4 R*U S GPO 1986 0 824 538/455


NRC Fo<<tn 366A (983)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION U.S.NUCLEAR REGULATORY COMMISSION APPROVED OMB NO.3150-0104 EXPIRES: 8/31/88 FACILITY NAME (1)SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 TEXT//mom RMBB/4 nqakaf, UBB////4/N/HRC
~0 U.S. NUCLEAR REGULATORY COMMISSION NRC Form 388 (8.83)                                                                                                                                                                APPROVED 0MB NO. 3)604104 EXPIRES: S/31/88 LICENSEE EVENT REPORT (LER)
%%d/m SBSAS/(17)DOCKET NUMBER (2)o s o o o 40 0 YEAR 8 7 LER NUMBER (6)SEOUENTIAL NUMBER 0 6 REVISION NUMBER 00 03 PAGE (3)oF 0 ANALYSIS: This event is reportable per 10CFR50.73(a)(2)(iv) as an automatic actuation of the Auxiliary Feedwater System (AFW).There are no safety consequences as a result of this event.The Auxiliary Feedwater System started as required upon loss of Main Feedwater to maintain water.levels in the Steam Generators.
DOCKET NUMBER (2)                                          IIAGE 3 FACILITY NAME (II SHEARON HARRIS NUCLEAR POWER PLANT                                          UNIT 1                                                          0 5 0 0 0                    400                        10FP      3
The Main Feedwater Pumps low flow trip is set at approximately 5000 gpm.Failure of the recirculation valve to open results in a pump trip at only relatively low power levels (0-15%).In this situation, the second Main Feed Pump is not running and the trip of one feed pump will automatically result in AFW actuation.
("MAIN FEEDWATER RECIRCULATION FLOW CONTROL VALVE FAILED RESULTING IN A MAIN FEEDWATER PUMP      'B'RIP              ON LOW FLOW ACTUATING AUXILIARY FEEDWATER SYSTEM EVENT DATE (5)                        LER NUMBER (8)                            REPORT DATE (7)                                OTHER FACILITIES INVOLVED (8)
If AFW flow does not maintain Steam Generator Water levels, reduction in power and/or reactor trip may be required.Failure of the valve to remain closed at higher power levels can also produce a pump trip by increasing the pumps flow to runout conditions.
Er ry SEOUENTIAL DAY          YEAR            FACILITYNAMES                              DOCKET NUMBER(S)
An event similar to this was reported in LER-87-037-00.
MONTH      OAY      YEAR      YEAR            NUMBER      '&A NUMBER MONTH 0    5      0          0        0 0 7 2        28 787                          0      4 6        0      0 0          8 2 0              8 7                                                        0    5    0            0.        0 THIS REPORT IS SUBMITTED PUASUANT-T0 THE REOUIREMENTS OF 10 CFR ()r (Check one or more                          of the folloryinpl (11 OPEAATINQ MODE (8)                    20A02(B)                                    20.405(c)                                50.73(el(20(v)                                    73.71(II) 20.405(el(1) (0                                      0)  '0.38(c) 50.73(e)(21(vl                                    73.71(cl POWER LEVEL                                                                                                                  50.73(el(2) (vS)                                  OTHER (Specify In Ahrtrect p p                .20A05(e) (1)(EI                              50.38(cl (2)
In this case, the worst consequences would occur at 100%power.Loss of one Main Feedwater Pump at this power level results in a Reactor Trip due to low Steam Generator water levels.CORRECTIVE ACTION: 1.The loose linkage on the Feed Pump Recirculation valve was repaired.E Action to Prevent Recurrence:
INIorNend In Teer, HRC Form 20.405(el(1)(lll)                            50.73(e) (2l(I)                          50.73( ~ )(2)(vill)(A)                            366A) 20AOS(e)  ll) (lv)                          50.73(e) (2) III)                        50.73( ~ ) (2l(vill)(BI 20.405( ~ )(1)(v)                            50,73(e) (2) Bll)                        50,73(e) (2)(e)
1.A plant maintenance checklist has been developed to monitor the recirculation valve Feedback linkages monthly to ensure they are in working condition.
LICENSEE CONTACT FOR THIS LER (12I NAME                                                                                                                                                                  TELEPHONE NUMBER AREA CODE R. SCHWABENBAUER  REGULATORY COMPLIANCE 9      193 62 -26 69 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)
2.A Plant Change Request (PCR-1829) is being generated to look at changing out the valve trim on the Feed pump recirculation valve ard/o.installing a breakdown orifice ahead of the valves.The purpose of this is to reduce the pressure drop in the area of the valve, therefore reducing vibration in the area.NRC FORM SBBA)4-RAI w U.S GPO:1986 0 624 538/455 Carolina Power 8,Light Company HARRIS NUCLEAR PROJECT P.O.Box 165 New Hill, NC 27562'AUG 20 3987 File Number: SHF/10-13510C Letter Number'HO-870486 (0)U.S.Nuclear Regulatory Commission ATTN: NRC Document Control Desk Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 DOCKET NO.50-400 LICENSE NO.NPF-63 LICENSEE EVENT REPORT 87-046-00 Gentlemen'.
MANUFA(r            EPORTABLE                    8                                                        MANUFACr            EPORTABLE CAUSE  SYSTEM  COMPONENT CAUSE  SYSTEM      COMPONENT                TURER            TO NPAOS      )                          )                                            TURER            TO NPRDS SL<rC. r ..:..rO....
In accordance with Title 10 to the Code of Federal Regulations, the enclosed Licensee Event Report is submitted.
0'    "~@3..:
This report fulfills the requirement for a written report within thirty (30)days of a reportable occurrence and is in accordance with the format set forth in NUREG-1022, September, 1983.RAW:dj Enclosure Very truly yours, Egcc/~R.A.Watson Vice President Harris Nuclear Project cc.'Dr.J.Nelson Grace (NRC-RII)Mr.B.Buckley (NRR)Mr.G.Maxwell (NRC-SHNPP)MEM/HO-8704860/1/Osl}}
B      S  J          F C          M            2 0 MONTH            OAY  YEAR SUPPLEMENTAL REPORT EXPECTED (14)                                                                        EXPECTED SU 8 MISSION DATE (I SI YES Ilfyer, complete  EXPECTED sU64IISSIOH DATE)                                  X            NO ABSTRACT (Limit to I400 rpecet, Ie., epprorrlmerery fifteen elnpre rpete tyPervrltren lintel (18)
ABSTRACT The plant was operating at 1 percent reactor power in Mode 2, Plant Start-up, on July 22, 1987. Only one Main Feedwater Pump,
                                                                                                                            'B', was in service.
Feedwater Pump tripped on low-flow which caused the automatic start, as,
                                                                                                                                                                                  'B'ain required, of both motor driven Auxiliary Feedwater Pumps.
The      Auxiliary Feedwater                          Pumps          started              and ran as required to supply ~ater to the steam generators.                              Plant        temperature and pressure remained stable at normal no            load        values.            An operator subsequently started the                                                  'A'ain Feedwater Pump                    and    secured          the Auxiliary Feedwater Pumps.
O          The cause            of the low flow                    was      investigated.                    The Feedback                linkage on the Pump        recirculation valve                                was found      loose.          This prevented the Ron.a
                                                                                                                                                                                            'B'eedwater OE2 (x) o          actuator from receiving                              a  signal to open and caused the low flow condition for OO h (T)          the      'B'eedwater                    Pump.
(X) O (A~              The root cause of the failure was vibration of the valve. The loose linkage OV              on the Feed pump Recirculation valve was repaired.                                                                A plant maintenance OQ                                                                                        monitor              the  recirculation                  valve Feedback OQ                checklist has been developed to 07<
O                linkages monthly to prevent a recurrence                                                      of  this  failure.                  A Plant Change Request was also generated to investigate                                                        and  resolve          the        high        vibration O():
experienced by the recirculation valve.
(x)a.(f)
The event            is reportable per                        10CFR50.73                  (a)(2)(iv)      as an            automatic actuation of u            F      ture Auxiliar Feedwater                                  S    stem).
reRC Form 388
 
NRC Form 366A (94LI)                                                                                                                         U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER) TEXT CONTINUATION                                               APPROVEO OMB NO.      3150M)04 EXP)RES/ 8/3 I/88 FACILITYNAME (11                                                                OOCKET NUMBER (2)
LER NUMBER (6)                        PAGE (31 SHEARON HARRIS NUCLEAR POWER PLANT                                                                          YEAR $,/ i SEQUENTIAL      REVISION OLRI    NUMBER        NUMBER UNIT      1 TEXT ///more Eoeoe )I /))rrBed, Iree ddlobnsl HRC Frnn 3$ !143) (17) 0  5    0  0  0  40 08                  046            00 02              oF 0 DESCRIPTION:
The plant was operating at 1 percent reactor power in Mode 2, Plant Start-up, on July 22, 1987. Only one Main Feedwater Pump, 'B', (EIIS:SJ) was in service at the time. A pump low-flow alarm was received in the Main Control Room and an auxiliary operator was dispatched to check the position of the recirculation valve, 1FW-39.(Masoneilan Valve 6 Actuator Model Number 37-40412-8A-6).. - The 'valve was reported to be approximately 50 percent open.
At 0500 hours                  'B'ain            Feedwater Pump tripped due to low flow. Both motor driven Auxiliary Feedwater Pumps (EIIS:BA) started as requi'red to supply water to the steam generators.
Reactor Coolant System (EIIS:AB) temperature and pressure,- and Steam Generator (EIIS:SB) water levels remained stable at normal no load values. An operator subsequently started the                                'A'ain    Feedwater Pump at 0534 hours. and secured the Auxiliary Feedwater                        Pumps.
CAUSE't was      first        thought the                    tripped    on  instantaneous    overcurrent        as the        flag on      'C'hase for                  'B'ain pump        Feedwater  Pump was      down. Electricians        checked the breaker and found no indications of an electrical fault. It was concluded that the flag was caused by the vibration when the breaker tripped.
The cause of the pump                            trip      was the low flow        trip  of the  'B'ain        Feedwater Pump.            The low flow resulted when the pump's recirculation valve did not respond to the signal to open. Instrument and Control technicians checked the
                'B'ain              Feedwater Pump recirculation valve and found a loose feedback linkage which kept the actuator from opening the valve. As a result, the recirculation flow decreased below the pump's low flow trip setpoint.                                                      The linkage was repaired and the pump started and ran normally.
It was          concluded that                  vibration of the valve              caused  the loosening of the linkage.              The high vibration is caused by t.he thruttling action of the valve.            The differential pressure across the valve is approximately 1700                                              psi.
The    vibration in the recirculation valve line has caused several failures in the operation of the recirculation valve. A broken linkage was first identified during power ascension testing where the recirculation valve would not shut. Prior to another event (reported in LER 87-005-00), the air line to the valve actuator had broken off and failed the valve to the full open position.
NRC FORM 3BBA rrr4 R                                                                                                                                      *U S GPO    1986 0 824 538/455
 
NRC Fo<<tn 366A                                                                                                    U.S. NUCLEAR REGULATORY COMMISSION (983)
LICENSEE EVENT REPORT (LER) TEXT CONTINUATION                                        APPROVED OMB NO. 3150-0104 EXPIRES: 8/31/88 FACILITY NAME (1)                                                     DOCKET NUMBER (2)                LER NUMBER (6)                    PAGE (3)
YEAR  SEOUENTIAL      REVISION SHEARON HARRIS NUCLEAR POWER PLANT                                                                         NUMBER        NUMBER UNIT     1 o  s  o  o  o    40    0 8 7      0      6        00 03          oF 0 TEXT //mom RMBB /4 nqakaf, UBB ////4/N/HRC %%d/m SBSAS/ (17)
ANALYSIS:
This event is reportable per 10CFR50.73(a)(2)(iv) as                                   an automatic actuation of the Auxiliary Feedwater System (AFW).
There are no safety consequences as a result of this event. The Auxiliary Feedwater System started as required upon loss of Main Feedwater to maintain water .levels in the Steam Generators.
The Main Feedwater                 Pumps       low flow   trip is   set at approximately 5000 gpm.
Failure of the recirculation valve to open results in a pump trip at only relatively low power levels (0-15%). In this situation, the second Main                                             Feed Pump is not running and the trip of one feed pump                                 will automatically       result         in AFW actuation.               If AFW flow does not maintain                   Steam Generator   Water     levels, reduction in power and/or reactor trip may be required. Failure of the valve to remain closed at higher power levels can also produce a pump trip by increasing the pumps flow to runout conditions. An event similar to this was reported in LER-87-037-00. In this case, the worst consequences would occur at   100%     power.       Loss     of one Main Feedwater           Pump   at this power level results in a   Reactor Trip due to low Steam Generator water levels.
CORRECTIVE ACTION:
: 1.     The loose         linkage       on   the Feed   Pump   Recirculation valve       was   repaired.
E Action to Prevent Recurrence:
: 1.     A   plant maintenance checklist has been developed to monitor the recirculation valve Feedback linkages monthly to ensure they are in working condition.
: 2.     A   Plant Change Request (PCR-1829) is being generated to look at changing out the valve trim on the Feed pump recirculation valve ard/o. installing a breakdown orifice ahead of the valves.                             The purpose of this is to reduce the pressure drop in the area                         of   the valve, therefore reducing vibration in the area.
NRC FORM SBBA                                                                                                                 w U.S GPO:1986 0 624 538/455
)4-RAI
 
Carolina Power 8,Light Company HARRIS NUCLEAR PROJECT P.O. Box 165 New   Hill, NC   27562
                                'AUG 20 3987 File Number: SHF/10-13510C Letter Number'HO-870486 (0)
U.S. Nuclear Regulatory Commission ATTN:   NRC Document Control Desk Washington,   DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT       UNIT 1 DOCKET NO. 50-400 LICENSE NO. NPF-63 LICENSEE EVENT REPORT 87-046-00 Gentlemen'.
In accordance with   Title 10 to the Code of Federal Regulations, the enclosed Licensee Event Report is submitted. This report fulfills the requirement for a written report within thirty (30) days of a reportable occurrence and is in accordance with the format set forth in NUREG-1022, September, 1983.
Very truly yours, Egcc/~
R. A. Watson Vice President Harris Nuclear Project RAW:dj Enclosure cc.'Dr. J. Nelson Grace   (NRC RII)
Mr. B. Buckley (NRR)
Mr. G. Maxwell (NRC SHNPP)
MEM/HO-8704860/1/Osl}}

Latest revision as of 06:02, 22 October 2019

LER 87-046-00:on 870722,main Feedwater Pump B Tripped Due to Low Flow Resulting in Automatic Start of Auxiliary Feedwater Pumps.Caused by Loose Linkage on Recirculation Valve Due to Vibration.Valve Repaired.Procedures changed.W/870820 Ltr
ML18004B912
Person / Time
Site: Harris Duke Energy icon.png
Issue date: 08/20/1987
From: Schwabenbauer, Watson R
CAROLINA POWER & LIGHT CO.
To:
NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
HO-870486-(O), LER-87-046, LER-87-46, NUDOCS 8709030005
Download: ML18004B912 (7)
v • d • e


Text

R JL RY INFORMATION DISTR 1 TI . SYSTEM (RIDS)

ACCESSION NBR: 870IT'030005 DOC. DATE: 87/08/20 NOTARIZED: NO DOCKET FACIL: 50-400 Shearon Harris Nuclear Poujer Planti Unit 1I Carolina 05000400 AUTH. NAME AUTHOR AFFILIATION SCHWABENBAUER Carolina Poujer 8i Light Co.

WATSONI R. A. Carolina Poujer 8. Light Co.

RECIP. NAME RECIPIENT AFFILIATION

SUBJECT:

LER 87-046-00: on 870722I main feedujater pump B tripped due to low floe resulting in automatic start of auxiliary feedujater pumps. Caused bg loose linkage on recirculation valve due to vibration. Valve repaired. Procedures changed. W/870820 ltr.

DISTRIBUTION CODE: IEEED COPIES RECEIVED:LTR f TITLE: 50. 73 Licensee Event Report <LER)I Incident Apt> etc.

ENCL Q SIZE:

NOTES: Ap'plication for permit reneuJal filed. 05000400 REC IP IENT COP IES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD2-1 LA 1 1 -PD2-1 PD 1 1 BUCKLEYr B 1 1 INTERNAL: ACRS MICHELSQN 1 1 ACRS MQELLER 2 2 AEQD/DQA 1 1 AEOD/DSP/NAS 1 AEOD/DSP/ROAB AEOD/DSP/TPAB 1 DEDRO 1 NRR/DEST/ADS 1 0 NRR/DEST/CEB 1 1 NRR/DEST/ELB 1 NRR/DEST/ I CSB 1 1 NRR/DEST/MEB NRR/DEST/MTB 1 NRR/DEBT/PSB 1 1 NRR/DEST/RSB 1 NRR/DEST/SGB 1 NRR/DLPG/HFB 1 1 NRR/DLPG/GAB 1 1 NRR/DQEA/EAB 1 1 NRR/DREP/RAB 1 1 N - /RPB 2 2 NRR/PMAS/ ILRB 1 ILE 02 1 RES DEPY QI 1 DI J 1 RES/DE/EIB 1 1 RQN2 FILE 01 1 1 EXTERNAL: EQ~oG GROHI M 5 5 H ST LOBBY WARD 1 1 LPDR 1 1 NRC PDR 1 1 NSIC HARRISI J 1 1 NSIC MAYBe G 1 TOTAL NUMBER OF COPIES REQUIRED: LTTR 43 ENCL 42

~0 U.S. NUCLEAR REGULATORY COMMISSION NRC Form 388 (8.83) APPROVED 0MB NO. 3)604104 EXPIRES: S/31/88 LICENSEE EVENT REPORT (LER)

DOCKET NUMBER (2) IIAGE 3 FACILITY NAME (II SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 0 5 0 0 0 400 10FP 3

("MAIN FEEDWATER RECIRCULATION FLOW CONTROL VALVE FAILED RESULTING IN A MAIN FEEDWATER PUMP 'B'RIP ON LOW FLOW ACTUATING AUXILIARY FEEDWATER SYSTEM EVENT DATE (5) LER NUMBER (8) REPORT DATE (7) OTHER FACILITIES INVOLVED (8)

Er ry SEOUENTIAL DAY YEAR FACILITYNAMES DOCKET NUMBER(S)

MONTH OAY YEAR YEAR NUMBER '&A NUMBER MONTH 0 5 0 0 0 0 7 2 28 787 0 4 6 0 0 0 8 2 0 8 7 0 5 0 0. 0 THIS REPORT IS SUBMITTED PUASUANT-T0 THE REOUIREMENTS OF 10 CFR ()r (Check one or more of the folloryinpl (11 OPEAATINQ MODE (8) 20A02(B) 20.405(c) 50.73(el(20(v) 73.71(II) 20.405(el(1) (0 0) '0.38(c) 50.73(e)(21(vl 73.71(cl POWER LEVEL 50.73(el(2) (vS) OTHER (Specify In Ahrtrect p p .20A05(e) (1)(EI 50.38(cl (2)

INIorNend In Teer, HRC Form 20.405(el(1)(lll) 50.73(e) (2l(I) 50.73( ~ )(2)(vill)(A) 366A) 20AOS(e) ll) (lv) 50.73(e) (2) III) 50.73( ~ ) (2l(vill)(BI 20.405( ~ )(1)(v) 50,73(e) (2) Bll) 50,73(e) (2)(e)

LICENSEE CONTACT FOR THIS LER (12I NAME TELEPHONE NUMBER AREA CODE R. SCHWABENBAUER REGULATORY COMPLIANCE 9 193 62 -26 69 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

MANUFA(r EPORTABLE 8 MANUFACr EPORTABLE CAUSE SYSTEM COMPONENT CAUSE SYSTEM COMPONENT TURER TO NPAOS ) ) TURER TO NPRDS SL<rC. r ..:..rO....

0' "~@3..:

B S J F C M 2 0 MONTH OAY YEAR SUPPLEMENTAL REPORT EXPECTED (14) EXPECTED SU 8 MISSION DATE (I SI YES Ilfyer, complete EXPECTED sU64IISSIOH DATE) X NO ABSTRACT (Limit to I400 rpecet, Ie., epprorrlmerery fifteen elnpre rpete tyPervrltren lintel (18)

ABSTRACT The plant was operating at 1 percent reactor power in Mode 2, Plant Start-up, on July 22, 1987. Only one Main Feedwater Pump,

'B', was in service.

Feedwater Pump tripped on low-flow which caused the automatic start, as,

'B'ain required, of both motor driven Auxiliary Feedwater Pumps.

The Auxiliary Feedwater Pumps started and ran as required to supply ~ater to the steam generators. Plant temperature and pressure remained stable at normal no load values. An operator subsequently started the 'A'ain Feedwater Pump and secured the Auxiliary Feedwater Pumps.

O The cause of the low flow was investigated. The Feedback linkage on the Pump recirculation valve was found loose. This prevented the Ron.a

'B'eedwater OE2 (x) o actuator from receiving a signal to open and caused the low flow condition for OO h (T) the 'B'eedwater Pump.

(X) O (A~ The root cause of the failure was vibration of the valve. The loose linkage OV on the Feed pump Recirculation valve was repaired. A plant maintenance OQ monitor the recirculation valve Feedback OQ checklist has been developed to 07<

O linkages monthly to prevent a recurrence of this failure. A Plant Change Request was also generated to investigate and resolve the high vibration O():

experienced by the recirculation valve.

(x)a.(f)

The event is reportable per 10CFR50.73 (a)(2)(iv) as an automatic actuation of u F ture Auxiliar Feedwater S stem).

reRC Form 388

NRC Form 366A (94LI) U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER) TEXT CONTINUATION APPROVEO OMB NO. 3150M)04 EXP)RES/ 8/3 I/88 FACILITYNAME (11 OOCKET NUMBER (2)

LER NUMBER (6) PAGE (31 SHEARON HARRIS NUCLEAR POWER PLANT YEAR $,/ i SEQUENTIAL REVISION OLRI NUMBER NUMBER UNIT 1 TEXT ///more Eoeoe )I /))rrBed, Iree ddlobnsl HRC Frnn 3$ !143) (17) 0 5 0 0 0 40 08 046 00 02 oF 0 DESCRIPTION:

The plant was operating at 1 percent reactor power in Mode 2, Plant Start-up, on July 22, 1987. Only one Main Feedwater Pump, 'B', (EIIS:SJ) was in service at the time. A pump low-flow alarm was received in the Main Control Room and an auxiliary operator was dispatched to check the position of the recirculation valve, 1FW-39.(Masoneilan Valve 6 Actuator Model Number 37-40412-8A-6).. - The 'valve was reported to be approximately 50 percent open.

At 0500 hours0.00579 days <br />0.139 hours <br />8.267196e-4 weeks <br />1.9025e-4 months <br /> 'B'ain Feedwater Pump tripped due to low flow. Both motor driven Auxiliary Feedwater Pumps (EIIS:BA) started as requi'red to supply water to the steam generators.

Reactor Coolant System (EIIS:AB) temperature and pressure,- and Steam Generator (EIIS:SB) water levels remained stable at normal no load values. An operator subsequently started the 'A'ain Feedwater Pump at 0534 hours0.00618 days <br />0.148 hours <br />8.829365e-4 weeks <br />2.03187e-4 months <br />. and secured the Auxiliary Feedwater Pumps.

CAUSE't was first thought the tripped on instantaneous overcurrent as the flag on 'C'hase for 'B'ain pump Feedwater Pump was down. Electricians checked the breaker and found no indications of an electrical fault. It was concluded that the flag was caused by the vibration when the breaker tripped.

The cause of the pump trip was the low flow trip of the 'B'ain Feedwater Pump. The low flow resulted when the pump's recirculation valve did not respond to the signal to open. Instrument and Control technicians checked the

'B'ain Feedwater Pump recirculation valve and found a loose feedback linkage which kept the actuator from opening the valve. As a result, the recirculation flow decreased below the pump's low flow trip setpoint. The linkage was repaired and the pump started and ran normally.

It was concluded that vibration of the valve caused the loosening of the linkage. The high vibration is caused by t.he thruttling action of the valve. The differential pressure across the valve is approximately 1700 psi.

The vibration in the recirculation valve line has caused several failures in the operation of the recirculation valve. A broken linkage was first identified during power ascension testing where the recirculation valve would not shut. Prior to another event (reported in LER 87-005-00), the air line to the valve actuator had broken off and failed the valve to the full open position.

NRC FORM 3BBA rrr4 R *U S GPO 1986 0 824 538/455

NRC Fo<<tn 366A U.S. NUCLEAR REGULATORY COMMISSION (983)

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION APPROVED OMB NO. 3150-0104 EXPIRES: 8/31/88 FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER (6) PAGE (3)

YEAR SEOUENTIAL REVISION SHEARON HARRIS NUCLEAR POWER PLANT NUMBER NUMBER UNIT 1 o s o o o 40 0 8 7 0 6 00 03 oF 0 TEXT //mom RMBB /4 nqakaf, UBB ////4/N/HRC %%d/m SBSAS/ (17)

ANALYSIS:

This event is reportable per 10CFR50.73(a)(2)(iv) as an automatic actuation of the Auxiliary Feedwater System (AFW).

There are no safety consequences as a result of this event. The Auxiliary Feedwater System started as required upon loss of Main Feedwater to maintain water .levels in the Steam Generators.

The Main Feedwater Pumps low flow trip is set at approximately 5000 gpm.

Failure of the recirculation valve to open results in a pump trip at only relatively low power levels (0-15%). In this situation, the second Main Feed Pump is not running and the trip of one feed pump will automatically result in AFW actuation. If AFW flow does not maintain Steam Generator Water levels, reduction in power and/or reactor trip may be required. Failure of the valve to remain closed at higher power levels can also produce a pump trip by increasing the pumps flow to runout conditions. An event similar to this was reported in LER-87-037-00. In this case, the worst consequences would occur at 100% power. Loss of one Main Feedwater Pump at this power level results in a Reactor Trip due to low Steam Generator water levels.

CORRECTIVE ACTION:

1. The loose linkage on the Feed Pump Recirculation valve was repaired.

E Action to Prevent Recurrence:

1. A plant maintenance checklist has been developed to monitor the recirculation valve Feedback linkages monthly to ensure they are in working condition.
2. A Plant Change Request (PCR-1829) is being generated to look at changing out the valve trim on the Feed pump recirculation valve ard/o. installing a breakdown orifice ahead of the valves. The purpose of this is to reduce the pressure drop in the area of the valve, therefore reducing vibration in the area.

NRC FORM SBBA w U.S GPO:1986 0 624 538/455

)4-RAI

Carolina Power 8,Light Company HARRIS NUCLEAR PROJECT P.O. Box 165 New Hill, NC 27562

'AUG 20 3987 File Number: SHF/10-13510C Letter Number'HO-870486 (0)

U.S. Nuclear Regulatory Commission ATTN: NRC Document Control Desk Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 DOCKET NO. 50-400 LICENSE NO. NPF-63 LICENSEE EVENT REPORT 87-046-00 Gentlemen'.

In accordance with Title 10 to the Code of Federal Regulations, the enclosed Licensee Event Report is submitted. This report fulfills the requirement for a written report within thirty (30) days of a reportable occurrence and is in accordance with the format set forth in NUREG-1022, September, 1983.

Very truly yours, Egcc/~

R. A. Watson Vice President Harris Nuclear Project RAW:dj Enclosure cc.'Dr. J. Nelson Grace (NRC RII)

Mr. B. Buckley (NRR)

Mr. G. Maxwell (NRC SHNPP)

MEM/HO-8704860/1/Osl

Retrieved from "https://kanterella.com/w/index.php?title=ML18004B912&oldid=1960968"