05000327/LER-1981-024-03, /03L-0:on 810314,problems Were Experienced W/Steam Supply Controls to steam-driven Auxiliary Feedwater Pump 1A-S.Probably Caused by Initial Pressure Spike & Bias Error Due to Clog in Sense Lines Causing Steam Supply Isolatio

/03L-0:on 810314,problems Were Experienced W/Steam Supply Controls to steam-driven Auxiliary Feedwater Pump 1A-S.Probably Caused by Initial Pressure Spike & Bias Error Due to Clog in Sense Lines Causing Steam Supply Isolation

ML20003E903
Person / Time
Site:	Sequoyah
Issue date:	04/10/1981
From:	Harding M, Wilkey A TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20003E897	List: 05000327/LER-1981-024, Forwards LER 81-024/03L-0 05000327/LER-1981-024-03, /03L-0:on 810314,problems Were Experienced W/Steam Supply Controls to steam-driven Auxiliary Feedwater Pump 1A-S.Probably Caused by Initial Pressure Spike & Bias Error Due to Clog in Sense Lines Causing Steam Supply Isolatio
References
LER-81-024-03L-03, LER-81-24-3L-3, NUDOCS 8104170468
Download: ML20003E903 (2)

LER-1981-024, /03L-0:on 810314,problems Were Experienced W/Steam Supply Controls to steam-driven Auxiliary Feedwater Pump 1A-S.Probably Caused by Initial Pressure Spike & Bias Error Due to Clog in Sense Lines Causing Steam Supply Isolation

Event date:
Report date:
3271981024R03 - NRC Website

text

-

,co-CouTRotstoCoI 1

I l

l 1.l@

iPttas PRINT on Tyrt att r.Ecuinto N,onuariam

~

i 8 IT IN ls IN le li @l o l o l' l a l o l o l o lo I lo lo I@l al 11 i l il i @l I' l@

l p

a 9 LICENsti CGGL 84 16 L8CtNst huMBL A 2S M

LICSNst ITP4 Je la Cal w t

^ e CON'T Q

y',',y dl0 15 l0 l0 1013I2l7 @lal311 l4 l 8 l 1 )@l 014 l 1l 0 l 8 l1 l@

4 6o 48 CocettNuvotM

'4 69 EvtNT DATE 34 Il RtPGAT OA14 80

' EVEidT DESCRIPTION AND PROS ASLE CONSECUENCES h Q l At 1204 CST with unit in cride 3 af ter a reactor trin, the steam-driven auxiliary feed-1' 1A-S was declared ineperable when the operator experienced problems with the g l water pir p [o 14 j l steam.sunniv controls. The plant entered action statement "a" of I.CO'3.7.1.2.

There 1

[ois;twasnoeffectonpublichealthorsafety. There have been no previous occurrences.'

g l

rrra i i

~

o 7 i

l F5Te 1 1 I

l 7. es so SYsitu CAust Caust

COue, vatvg CODE CCCE *

$UsCoct COusCNENT CODE

$US CCOE sysCC0f l0I9l I

l l

l l

. l l

lI Nl SI TI R I'ff lh Wh W h n

2

. i.

i.

n st out NtiaL OCCunntNCC

• ptPOAT REVis3CM Liaiso EVENf vt AR mt OnT NO.

4005 TYPE sec.

@,agg Iaill l_t I o'f 214 I Lgj I rl 3 I l t. )

L--J

' Lo.J

_n n

n u

u n

n n

n 2.

u IL S.

WAN saCTvate 1AE '

• Or CN FLa T Wit u l*0VMS S S tl O POn sut*L A l r l@l P l@

lcl@

L2J@

lololo10 I I vi@

IN l@

Lt_J@

la I al si al 3J 34 at 36 37 40 el e2 4J 44 43 CAUSE DEtCRIPTICN AND CCARECTIVE ACT:CNS h p loj lThe'nroblem's with the steam sunniv cont'rols davalo,ad when the sta a sunnh. to

• 5 'a i

g l pump was automatically isolated bv PDIS-1-17 and~18.

Initial trouble-shootine cois1d not i

,,,,, ldupitcate the problem. After three successful tests. the cump was declared onerable

, 3 l at 2300 CST.

Sub. sequent investigations resulted in modifying tihe sstpoints for'

,,,,,;PDIS-1-17 and 18.

s 6 i so oturn status @

$is$vSN h-

's*r'M S.'

seowta eiscovany otsCnietioN

.I 8 l S I l C lh l 0 l 0 l 0 l@l NA l

lA [gl.Operatorobservation l

9

' C nvity Co'0ftNT A

mttratt CF ntLE ASE AMCQNT QF ACTIV17Y LOCATIO*0 0F mittASE NA l

l NA MW [Z__j@l io er nsowlt t urcsuats nevoeta tvet otsCaintic4

.~

R lOl0l0l@lZlhl NA 9.

T 0 9 et of 13 er a:ows t msunits N Jwet m O t sC R *itON d, lOlOlOl@l NA n

Lots 08 C4 DawaCE TO FACILITY TV't CisCaseisON NA I

d, lZlhl e

io

~

c-

'~

~*

essuto OtsCairtiON NRC USE ONL v custicity li f e l L2J8I I

11 I I I ' ! ' ' ' i l I n

s e e io se as

~ ~

• N'ame of Preparer M.

9 Wrdin2/A. M. Wilkev.

Phone (615) 342-8317 8104170468

Tcon:ccee Valley Authority Sequoyah Nuclear Plant LER SUPPLEMENTAL INFORMATION SQRO-50-327/81024 Technical Specification Involved:

3.7.1.2.b Reported Under Technical Specification:

6.9.1.13.b Date of Occurrence: 3/14/81 Time of Occurrence: 1204 CST Identification and Description of Occurrence:

Operator experienced difficulty with oceam supply controls to steam-driven 4

l auxiliary feedwater pump 1A-S.

Pump was declared inoperable.

i Conditions Prior to Occurrence:

Unit in mode 3 following reactor trip Apparent Cause of Occurrence:

An initial pressure spike (over 50-feet WC) in additior. to a bias error caused by a clog in the sense lines to PDIS-1-17 and 18 (approximately 5-feet WC) caused PDIS-1-17 and 18 to isolate the steam supply to the i

AFW pump turbine.

Corrective Action

The setpoints for PDIS-1-17 and 18 were temporarily modified with engineering design's concurrence from 55.68 f t. WC to 95 f t. WC to prevent recurrence of this event in the future. A permanent setpoint change will be implemented by a design change request now being prepared and expected to be submitted by May 1, 1981.

l i

O e