ML18037A243

LER 80-007/03L-0:on 800303,while Shutdown for Maint,Attempts to Close Both Air Operated Outside Main Steam Isolation Valves Failed.Caused by Rust Buildup in Pilot Shuttle.New Instrument Air Sys Is Being Installed

ML18037A243
Person / Time
Site:	Nine Mile Point
Issue date:	03/20/1980
From:	NIAGARA MOHAWK POWER CORP.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML17053B514	List: ML17053B513 ML18037A243
References
LER-80-007-03L, LER-80-7-3L, NUDOCS 8003310281
Download: ML18037A243 (4)

Text

NRC I'ORM 366 V 43 I'VVI48 CIRlh hCVVI H I Vh I I4VIVIIIIIODIVIN

\7.&I 4.

LlCENSEE. EVENT REPORT CONTROL BLOCK Qi {PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

I

~O 7 8 9 N Y N LICENSEE CODE H P 1 14 Q20 15 0 0 0 0 0 0 0 0 25 Q3 26 4 1 1 LICENSE TYPE 1 104~08 30 57 CAT 58 CON'T

~87 7 8 SOURCE LJQ 60 61 DOCKET NUMBER 68 0 69 EVENT DATE 0

74 QB 75 REPORT DATE 80 QB EVENT DESCRIPTION AND PROBABL,E CONSEQUENCES QIO SEAT CE H'T

~O3

~O

~OS

~OB

~O7

~OB 80 7 8 SYSTEM CAUSE CAUSE COMP VALVE CODE CODE SUBCODE COMPONENT CODE SUBCODE SUBCODE

~OB ~CD Qll E 072 ~D 12 073 13 77 A L 77 0 0 G4 18 LJJ 19 GI ~~

20 GR 7 8 9 10 11 SEQUENTIAL OCCURRENCE REPORT REVISION 017 LERIRO RIRRR7 ACTION, FUTURE EVENT YEAR

~00 21 22

+

23

~00 24 REPORT No.

7 26 Qa 27

~0 28 ATTACHMENT CODE 29 NPRD.4 TYPE 30 31 PRIME COMP.

No.

32 COMPONENT

~

EFFECT SHUTDOWN TAKEN ACTION ON PLANT METHOD HOURS Q22 SUBMITTED FORM SUB. SUPPLIER MANUFACTURER

~QIB ~QIB 34

~Q2O 35

~Q2 36 37 0 0 0 0 40

~Y 41 Q23 ~YQ24 42 43 Q25 44 N

47 Q26 33 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS Q27 o Disassembly of the ilot valves revealed that rust buildu had occurred in the ilot shuttle. The rust was robabl from the instrument air s s-tern. At present, a new instrument air system is bein installed which should eliminate the moisture problem. Procedures are also bein chan ed 4 to require cleanin & ins ection of the ilot shuttle valve internals.

80 7

METHOD OF TR POWER OTHER STATUS QBO DISCOVERY DISCOVERY DESCRIPTION Q32

~l5 D Q28 ~00 10 0 Q28 NA 44

~AQ31 45 46 OPERATOR OBSERVATION 80 7 8 9 12 13 ACTIVITY CONTENT RELEASED OF RELEASE AMOUNT OF ACTIVITY NA Q NA LOCATION OF RELEASE Q 6 ~Z Q33 ~ZQ34 7 8 9 10 11 44 45 80 PERSONNEI. EXPOSURES NUMBER TYPE DESCRIPTION Q39

~l7 ~00 0 Q37 Z Q38 NA

7. 8 9 1112 PERSONNEL INJURIES, 13 80 NUMBER OESCRIPTIONQ41

~li! ~00 0 Q43 NA 80 7 8 9 11 12 LOSS OF OR DAMAGE To FACILITY TYPE DESCRIPTION Q43 L~IQ42 NA 7 8 9 10 80

~74 ISSUED 1

PUBLICITY IO44 DESCRIPTION 1 iIA

~

' NRC USE ONLY le LL~~-..i

, 4 43 ~ ", ~ 77! 7 I 47 A? I I I

EVENT DESCRIPTION AND PROBABLY CONSEQUENCES While shut down for maintenance, attempts to close both air operated out-side main steam isolation valves failed. Technicians disconnected the bleed off line to the air operator of one MSIV and jarred the pilot shuttle valve.

At this time the MSIV closed. Without any changes, a second attempt was made to close the other MSIV. The attempt succeeded. Subsequent testing revealed that both valves opened and closed properly. The event occurred with the reactor mode switch in "refuel" at zero power. As a result, the consequences were insignificant.

EVENT DESCRIPTION AND PROBABLY CONSEQUENCES While shut down for maintenance, attempts to close both air operated out-side main steam isolation v'alves failed. Technicians disconnected the bleed off line to the air operator of one MSIV and jarred the pilot shuttle valve.

At this time the MSIV closed. Without any changes, a second attempt was made to close the other MSIV. The attempt succeeded. Subsequent testing revealed that both valves opened and closed properly. The event occurred

with the reactor mode switch in "refuel" at zero power. As a result, the consequences were insignificant.