Solenoid-Operated Valve Failures Resulted in Turbine OverspeedML031190391 |
Person / Time |
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Site: |
Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant ![Entergy icon.png](/w/images/7/79/Entergy_icon.png) |
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Issue date: |
12/20/1991 |
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From: |
Rossi C Office of Nuclear Reactor Regulation |
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To: |
|
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References |
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IN-91-083, NUDOCS 9112160318 |
Download: ML031190391 (11) |
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Similar Documents at Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant |
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Category:NRC Information Notice
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Mclaughlin on NRC, Regarding NRC Information Notice 2006-13: Groundwater Contamination 2020-09-03 The following query condition could not be considered due to this wiki's restrictions on query size or depth: <code> [[:Beaver Valley]] OR [[:Millstone]] OR [[:Hatch]] OR [[:Monticello]] OR [[:Calvert Cliffs]] OR [[:Dresden]] OR [[:Davis Besse]] OR [[:Peach Bottom]] OR [[:Browns Ferry]] OR [[:Salem]] OR [[:Oconee]] OR [[:Mcguire]] OR [[:Nine Mile Point]] OR [[:Palisades]] OR [[:Palo Verde]] OR [[:Perry]] OR [[:Indian Point]] OR [[:Fermi]] OR [[:Kewaunee]] OR [[:Catawba]] OR [[:Harris]] OR [[:Wolf Creek]] OR [[:Saint Lucie]] OR [[:Point Beach]] OR [[:Oyster Creek]] OR [[:Watts Bar]] OR [[:Hope Creek]] OR [[:Grand Gulf]] OR [[:Cooper]] OR [[:Sequoyah]] OR [[:Byron]] OR [[:Pilgrim]] OR [[:Arkansas Nuclear]] OR [[:Three Mile Island]] OR [[:Braidwood]] OR [[:Susquehanna]] OR [[:Summer]] OR [[:Prairie Island]] OR [[:Columbia]] OR [[:Seabrook]] OR [[:Brunswick]] OR [[:Surry]] OR [[:Limerick]] OR [[:North Anna]] OR [[:Turkey Point]] OR [[:River Bend]] OR [[:Vermont Yankee]] OR [[:Crystal River]] OR [[:Haddam Neck]] OR [[:Ginna]] OR [[:Diablo Canyon]] OR [[:Callaway]] OR [[:Vogtle]] OR [[:Waterford]] OR [[:Duane Arnold]] OR [[:Farley]] OR [[:Robinson]] OR [[:Clinton]] OR [[:South Texas]] OR [[:San Onofre]] OR [[:Cook]] OR [[:Comanche Peak]] OR [[:Yankee Rowe]] OR [[:Maine Yankee]] OR [[:Quad Cities]] OR [[:Humboldt Bay]] OR [[:La Crosse]] OR [[:Big Rock Point]] OR [[:Rancho Seco]] OR [[:Zion]] OR [[:Midland]] OR [[:Bellefonte]] OR [[:Fort Calhoun]] OR [[:FitzPatrick]] OR [[:McGuire]] OR [[:LaSalle]] OR [[:Fort Saint Vrain]] OR [[:Shoreham]] OR [[:Satsop]] OR [[:Trojan]] OR [[:Atlantic Nuclear Power Plant]] </code>.
[Table view]The following query condition could not be considered due to this wiki's restrictions on query size or depth: <code> [[:Beaver Valley]] OR [[:Millstone]] OR [[:Hatch]] OR [[:Monticello]] OR [[:Calvert Cliffs]] OR [[:Dresden]] OR [[:Davis Besse]] OR [[:Peach Bottom]] OR [[:Browns Ferry]] OR [[:Salem]] OR [[:Oconee]] OR [[:Mcguire]] OR [[:Nine Mile Point]] OR [[:Palisades]] OR [[:Palo Verde]] OR [[:Perry]] OR [[:Indian Point]] OR [[:Fermi]] OR [[:Kewaunee]] OR [[:Catawba]] OR [[:Harris]] OR [[:Wolf Creek]] OR [[:Saint Lucie]] OR [[:Point Beach]] OR [[:Oyster Creek]] OR [[:Watts Bar]] OR [[:Hope Creek]] OR [[:Grand Gulf]] OR [[:Cooper]] OR [[:Sequoyah]] OR [[:Byron]] OR [[:Pilgrim]] OR [[:Arkansas Nuclear]] OR [[:Three Mile Island]] OR [[:Braidwood]] OR [[:Susquehanna]] OR [[:Summer]] OR [[:Prairie Island]] OR [[:Columbia]] OR [[:Seabrook]] OR [[:Brunswick]] OR [[:Surry]] OR [[:Limerick]] OR [[:North Anna]] OR [[:Turkey Point]] OR [[:River Bend]] OR [[:Vermont Yankee]] OR [[:Crystal River]] OR [[:Haddam Neck]] OR [[:Ginna]] OR [[:Diablo Canyon]] OR [[:Callaway]] OR [[:Vogtle]] OR [[:Waterford]] OR [[:Duane Arnold]] OR [[:Farley]] OR [[:Robinson]] OR [[:Clinton]] OR [[:South Texas]] OR [[:San Onofre]] OR [[:Cook]] OR [[:Comanche Peak]] OR [[:Yankee Rowe]] OR [[:Maine Yankee]] OR [[:Quad Cities]] OR [[:Humboldt Bay]] OR [[:La Crosse]] OR [[:Big Rock Point]] OR [[:Rancho Seco]] OR [[:Zion]] OR [[:Midland]] OR [[:Bellefonte]] OR [[:Fort Calhoun]] OR [[:FitzPatrick]] OR [[:McGuire]] OR [[:LaSalle]] OR [[:Fort Saint Vrain]] OR [[:Shoreham]] OR [[:Satsop]] OR [[:Trojan]] OR [[:Atlantic Nuclear Power Plant]] </code>. |
- s
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C. 20555 December 20, 1991 NRC INFORMATION NOTICE 91-83: SOLENOID-OPERATED VALVE FAILURES RESULTED
IN TURBINE OVERSPEED
Addressees
All holders of operating licenses or construction permits for nuclear power
reactors.
Purpose
The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice
to alert addressees to turbine overspeed problems and turbine trip failures
resulting from the failures of multiple solenoid-operated valves (SOVs). It is
expected that recipients will review the information for applicability to their
facilities and consider actions, as appropriate, to avoid similar problems.
However, suggestions contained in this information notice are not NRC require- ments; therefore, no specific action or written response is required.
Background
Westinghouse turbines are tripped using a combination of electro-hydraulic
control (EHC) fluid and auto-stop oil (Attachment 1). In the electro-hydraulic
portion, SOVs dump the fluid to the EHC sump, causing the throttle valves, reheat stop valves, intercept valves, and the governor valves to shut, stopping
the flow of steam to the turbine. Failure of the SOVs in the EHC system to
open could lead to the turbine overspeeding. Several events have occurred in
the industry that involved the failure of SOVs that must operate for turbine
emergency trip and overspeed protection. The consequences of these failures
have varied according to the initiating event and the type of SOV failure.
These failures suggest that there are weaknesses in the preventive maintenance
and testing of these SOVs.
Description of Circumstances
On November 9, 1991, Unit 2 of the Salem Nuclear Generating'Station sustained
severe damage to its turbine and generator. The event occurred while'the
Public Service Electric and Gas Company (the licensee) was conducting routine
turbine testing at 100-percent power. The licensee bypassed the turbine's
auto-stop oil trip mechanism in accordance with the test procedure. During the
test, an oil pressure perturbation occurred in the auto-stop trip system, the
exact cause of which is yet to be determined. This caused the interface valve
to open and thereby depressurized the EHC fluid. Both the turbine and the
reactor tripped and, as expected, all turbine stop valves closed. However, the
emergency trip solenoid valve failed to open upon receiving the trip signal.
9112160318
-e \\\xt ar - //c,
,IN91-83
-,December 20, 1991 When the auto-stop oil repressurized, the interface valve closed, and all
turbine stop valves reopened allowing steam flow into the turbine. As
designed, the generator output breakers had opened upon receiving the reactor
trip signal, so the steam flow through the unloaded turbine caused the turbine
to overspeed. Both overspeed protection controller (OPC) solenoid valves
failed to open preventing the governor valves and intercept valves from closing
properly. The turbine continued to overspeed to an estimated 160-percent of
rated speed. Operators observed increasing noise and vibration from the
turbine and a fire at the generator. The low pressure turbine blades penetra- ted the turbine shroud. The overspeed resulted in severe damage to the low
pressure turbine, the generator exciter unit, the condenser, and associated
support structures, systems, and components.
Discussion
The staff sent an augmented inspection team (AIT) to the site to investigate
the event. The AIT concluded that the proximate cause of the event was the
failure of the emergency trip solenoid valve and both overspeed protection
controller solenoid valves to open when energized. The specific failure
mechanisms of the Parker-Hannifin SOVs are yet to be determined, but prelimi- nary analysis indicated that the pilot valve assembly in each solenoid unit was
mechanically bound sufficiently to prevent movement. Other previous failures
of these valves in the industry have also been attributed to mechanical bind- ing, corrosion, and worn or pinched elastomeric parts.
Several precursory factors contributed to the event. The licensee for the
Salem Nuclear Generating Station has no preventive maintenance program for any
of these three SOVs. The surveillance and operational testing of the turbine
trip and overspeed circuits does not specifically verify the proper hydraulic
functioning of each SOY independently. Further, information concerning previ- ous SOV failures has not been well disseminated.
The licensee had two earlier indications of problems with these SOVs. Similar
valves on Salem Unit 1 required replacement, yet the licensee had not effec- tively verified the operability of the SOYs in Unit 2. Another indication
occurred during a startup in October 1991. The OPC solenoid valves failed to
open when a test of the system was performed. The licensee was required to
verify proper OPC operation by closing the intercept valves when the OPC test
switch was activated. The intercept valves did not close, indicating a possi- ble malfunction of both of the OPC solenoid valves. The results were
apparently misinterpreted, leading management to believe a procedure problem
existed, rather than an equipment problem. The licensee continued the startup
without further diagnosis and resolution. The staff will include more details
of this event in NRC Inspection Report 50-311/91-81 when issued.
Previous Events
The following previous events involved failures of SOVs in the turbine trip
system during reactor trip events:
On April 6, 1985, at the R. E. Ginna Nuclear Power Plant, the turbine failed to
trip automatically following a reactor trip because of mechanical binding of
the emergency trip solenoid valve. -
IN 91-83 December 20, 1991 On February 28, 1988, at the Crystal River Plant, Unit 3, the turbine failed to
trip automatically following a reactor trip because of a faulty emergency trip
solenoid valve.
On September 10, 1990, at Salem, Unit 1, the reactor tripped because of a steam
generator water level transient caused by a spurious overspeed signal. Mechan- ical binding prevented the OPC solenoid valves from functioning.
On September 29, 1990, at Ginna, the reactor tripped because of personnel
error, but mechanical binding prevented the turbine emergency trip solenoid
valve from functioning.
These events indicate that proper maintenance and operability testing of both
the emergency trip solenoid valve and the OPC solenoid valves is prudent.
Related Generic Communications
The staff issued Generic Letter 91-15, "Operating Experience Feedback Report, Solenoid-Operated Valve Problems at U.S. Reactors," to distribute NUREG-1275, Volume 6, to industry. This document provided the staff's analysis of recent
U.S. light water reactor experience (primarily 1984-1989) with SOYs.
Appendix A of NUREG-1275, Volume 6, cited similar SOV failures at four other
plants. The staff noted the susceptibility of SOVs to common-mode failures.
The staff found that most SOVs cannot tolerate contaminants, need preventative
maintenance or periodic replacement, and have a propensity for rapid aging and
deterioration when subjected to elevated temperatures. The staff provided
recommendations to aid in preventing common-mode SOV failures.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact one
of the technical contacts listed below or the appropriate Office of Nuclear
Reactor Regulation (NRR) project manager.
Charles E. Rossi, Dir or
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical contacts: John White, Region I
(215) 337-5114 David Gamberoni, NRR
(301) 504-1171 Attachments:
1. Westinghouse Electro-Hydraulic Control System
2. List of Recently Issued NRC Information Notices
II
EMERGENCY TRIP
SOLENOID VALVE
C
TO EHC
SUMP
...... I................ AUTO-STOP OIL SYSTEM
INTERFA'
VALVE
TO En-IC
SUIMP
c
ELECTRO-HYORAULIC CONTROL FLUID
................ AUTO-STOP OIL
TO EHC
SUAJP
OVERSPEED PROTECTION (D Z r'
CONTROLLER SOLENOID Gm n rt
VALVES (D 9 I' 03
0oD11 co B
a
LO (D
WESTINGHOUSE ELECTRO-HYDRAULIC CONTROL SYSTEM Ft M
o
o_ _
'\Attachment2 IN 91-83 December 20, 1991 LIST OF RECENTLY ISSUED
NRC INFORMATION NOTICES
Information Date of
Notice No. Subject Issuance Issued to
91-18, High-Energy Piping Failures 12/18/91 All holders of OLs or CPs
Supp. 1 Caused by Wall Thinning for nuclear power reactors.
91-82 Problems with Diaphragms 12/18/91 All holders of OLs or CPs
in Safety-Related Tanks for nuclear power reactors.
91-81 Switchyard Problems that 12/16/91 All holders of OLs or CPs
Contribute to Loss of for nuclear power reactors.
Offsite Power
91-80 Failure of Anchor 12/11/91 All holders of OLs or CPs
Head Threads on Post- for nuclear power reactors.
Tensioning System During
Surveillance Inspection
91-79 Deficiencies in the 12/06/91 All holders of OLs or CPs
Procedures for Instal- for nuclear power reactors.
ling Thermo-Lag Fire
Barrier Materials
88-92, Potential for Spent 11/29/91 All holders of OLs or CPs
Supp. 1 Fuel Pool Draindown for nuclear power reactors.
91-78 Status Indication of 11/28/91 All holders of OLs or CPs
Control Power for for nuclear power reactors.
Circuit Breakers Used
in Safety-Related Appli- cations
90-57, Substandard, Refur- 11/27/91 All holders of OLs or CPs
Supp. 1 bished Potter & Brum- for nuclear power reactors.
field Relays Repre- sented as New
91-77 Shift Staffing at 11/26/91 All holders of OLs or CPs
Nuclear Power Plants for nuclear power reactors.
OL = Operating License
CP = Construction Permit
HE
UNITED STATES
NUCLEAR REGULATORY COMMISSION FIRST CLASS MAIL
POSTAGE 6 FEES PAID
WASHINGTON, D.C. 20555 USNRC
PERMIT No 0-57 OFFICIAL BUSINESS
PENALTY FOR PRIVATE USE, $300
I
II
IN 91-83 December 20, 1991 On February 28, 1988, at the Crystal River Plant, Unit 3, the turbine failed to
trip automatically following a reactor trip because of a faulty emergency trip
solenoid valve.
On September 10, 1990, at Salem, Unit 1, the reactor tripped because of a steam
generator water level transient caused by a spurious overspeed signal. Mechan- ical binding prevented the OPC solenoid valves from functioning.
On September 29, 1990, at Ginna, the reactor tripped because of personnel
error, but mechanical binding prevented the turbine emergency trip solenoid
valve from functioning.
These events indicate that proper maintenance and operability testing of both
the emergency trip solenoid valve and the OPC solenoid valves is prudent.
Related Generic Communications
The staff issued Generic Letter 91-15, "Operating Experience Feedback Report, Solenoid-Operated Valve Problems at U.S. Reactors," to distribute NUREG-1275, Volume 6, to industry. This document provided the staff's analysis of recent
U.S. light water reactor experience (primarily 1984-1989) with SOVs.
Appendix A of NUREG-1275, Volume 6, cited similar SOV failures at four other
plants. The staff noted the susceptibility of SOVs to common-mode failures.
The staff found that most SOVs cannot tolerate contaminants, need preventative
maintenance or periodic replacement, and have a propensity for rapid aging and
deterioration when subjected to elevated temperatures. The staff provided
recommendations to aid in preventing common-mode SOV failures.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact one
of the technical contacts listed below or the appropriate Office of Nuclear
Reactor Regulation (NRR) project manager.
Charles E. Rossi, Direc r
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical contacts: John White, Region I
(215) 337-5114 David Gamberoni, NRR
(301) 504-1171 Attachments:
1. Westinghouse Electro-Hydraulic Control System
2. List of Recently Issued NRC Information Notices
Document Name: IN 91-83 *SEE PREVIOUS CONCURRENCES
- REGION I *EAB:DOEA:NRR *SC:REGION I *SC:EAB:DOEA:NRR
IMoghissi DGamberoni JWhite DFischer
12/05/91 12/09/91 12/10/91 12/13/91
- C.-AB DOEA:NRR *Tech Ed *C:OGCB:DOEA:NRR D:DOEA:NR eI4 g
A~natTee CBerlinqer CRossi x--V
12/13/91 12/10/91 12/13/91 12,y4,91
IN 91-XX
December xx, 1991 On September 10, 1990, at Salem, Unit 1, the reactor tripped because of a steam
generator water level transient caused by a spurious overspeed signal. Mechanical
binding prevented the OPC solenoid valves from functioning.
On September 29, 1990, at Ginna, the reactor tripped because of personnel
error, but mechanical binding prevented the turbine emergency trip solenoid
valve from functioning.
These events indicate that proper maintenance and operability testing of both
the emergency trip solenoid valve and the OPC solenoid valves is prudent.
Related Generic Communications
The staff issued Generic Letter 91-15, "Operating Experience Feedback Report, Solenoid-Operated Valve Problems at U.S. Reactors," to distribute NUREG-1275 to
industry. This document provided the staff's analysis of recent U.S. light
water reactor experience (primarily 1984-1989) with SOVs. The staff found that
most SOVs cannot tolerate contaminants, need preventative maintenance or
periodic replacement, and have a propensity for rapid aging and deterioration
when subjected to elevated temperatures. The staff provided recommendations to
aid in preventing further SOV problems.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact one
of the technical contacts listed below or the appropriate Office of Nuclear
Reactor Regulation (NRR) project manager.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical contacts: John White, Region I
(215) 337-5114 David Gamberoni, NRR
(301) 504-1171 Attachments:
1. Westinghouse Electro-Hydraulic Control System
2. List of Recently Issued NRC Information Notices
OFC : *REGION I : *EAB:DOEA:NRR
- SC:REGION I : SC: AB:DOEA:NRR :
_____ _______________:---------- - -- - t
NAME : IMoghissi : DGamberoni : JWhite : DFis'Htere:
_____--__ _ _ _ _ -- _ _ -_ _ _ _ _ _ _ _ -_ _-- _ -__--------_---
- - - - ---- -- - - - - - - -
DATE : / /91 : / /91 : / /91 : -l/13/91 OFC : :EAB:DOEA:NRR : *Tech Ed : C:OGCijpq RR : D:DOEA:NRR :
5:rSFi CS- -------------------- -------- A-------
NAME : A haffee : CBerlinger : CRossil:
_____ ---------
__ _ _ __ _ _ _ -- - - -- - ---- __ _:-- __
- - __-------
- - - - -:-- - - - - - -
DATE : 1d /i3/91 : / /91 : 1-/)/91 / /91 OFFICIAL RECORD COPY *SEE PREVIOUS CONCURRENCES
Document Name IN91/SALEM
-3-
9/10/90 At Salem, Unit 1, the reactor tripped due to a steam generator water
level transient caused by a spurious overspeed signal. The OPC solenoid valves
did not function due to mechanical binding.
9/29/90 At Ginna, the reactor tripped due to personnel error, but the turbine
emergency trip solenoid valve failed to function due to mechanical binding.
It is apparent from these events that proper maintenance and operability
testing of both the ET solenoid valve and the OPC solenoid valves is prudent.
Related Generic Communications
NUREG-1275, Operating Experience Feedback Report - Solenoid-Operated Valve
Problems, which was distributed to industry via Generic Letter 91-15, analyzed
recent U.S. light-water reactor experience (primarily 1984-1989) with solenoid- operated valves (SOVs). It was found that most SOVs cannot tolerate contaminants, need preventative maintenance or periodic replacement, and have a propensity
for rapid aging and deterioration when subjected to elevated temperatures.
Various recommendations were provided to aid in the prevention of further SOV
problems.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact one
of the technical contacts listed below or the appropriate Office of Nuclear
Reactor Regulation project manager.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical contacts: John White, Region I
(215) 337-5114 David Gamberoni, NRR
(301) 492-1171 Attachments:
1. List of Recently Issued NRC Information Notices
OFC : REGION I : EAB:DOEA:NRR SC:REGION I : SC:EAB:DOEA:NRR
____-___ __ __-____-__
-- - - ___ __ _- A:-2 _---------------:------------- --
NAME : IMoghissi : DGamberoni wt : JWhite : DFischer
__- - -- - - - -- __ - _ -- _- -- __
- - __------
-- - -- - -- - -
DATE: / /91 : // /91 : / /91 : / /91 OFC : C:EAB:DOEA:NRR : Tech Ed C:OGCB:DOEA:NRR : D:DOEA:NRR :
_____-- -- - ----------------
________ _______:__--- ------- :-- -- -
NAME : AChaffee : ads, dh CBerlinger : CRossi
--------- I------- -----------------: ----------
DATE: / /91 : 12- /I/91 : / /91 : / /91 OFFICIAL RECORD COPY -( SEE PREV10ouS C Uorc-EjCES - ACHtb
Document Name IN91/SALEM
I PI
6' - .3' 'J
9/1/g10 At Salem, Unit 1, the reactor
levtI transient caused by A spurious overspeed tripped due to a
did not function due to mechanical binding, signal.
The:OPC $07eno atves
9/29/90 At ronnh
emgen"y trip So50nojd reactor
the tripped due to personnel error, but
V8lve failed to function the turbine
due to mechanical bindinn.
It Isapparent from thes *vents that
proper maintenance
testing of both the ET solenoid valve and the OPC Solenoidandvalves operability
Isprudent&
Related Generic Commnunicctiong
NORO-1275 ,perating Ex erieng Feedback eportave
wh c was wbems
recent US. light-waterstrbuzec onustry via gener
reactor experience (primarily terzed
operated vatves (SOVi)t It WAs found that 1984.198g) WitYsolenoid.
need preventativ maintenance most SOYs cannot tolerate contaminants, for rapid aging and deterioration or periodic replacement and have a propensity
Various raconmendatlons were provided when subjected to elevated tomPeratures.
problems. to aid inthe prevention of further $01 This Information notice requires
you have any questions about the no 8pecfic Action or written response. If
Information
of the technical contacts listed below or inthis notice please contact one
Reactor Regulition project manager, the appropriate Of ice of Nuclear
Charl'es £, Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical contacts: John White Region I
(215) 337-1114 n
' (ba\idGamberoni, NRR
(301) 492-1171 Attachmentst
1. List of Recently Issued NRC Information
Notices
OFCsw*
amVWNo: *
W~mmU46b...,.RR.,1ON1
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DATE: / /9l / /91 s IZ4 6 gl 5 / /91 UP -rc Ed-- M100 =1R _iEX-1R
NAME : AChaffee
- CBerlinger : CRosui
DATE; :/91 : /91 a 1/9I9 OFFICIAL RECORD COPY
Document Name IN91/$ALEM
.LC- WQf W L a w. -S - - -- - - .
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3-3
9/10/9D At Salem, Unit 1, the reactor tripped due to a steam enerator water
level transient caused by a spurious overspeed signal. The DPC solenoid valves
did not function due to mechanical binding.
9/W9/9O At Ginna the reactor tripped due to personnel error, but the turbine
emergency trip soienoid valve failed to function due to mechanical binding.
It is apparent from these events that proper maintenance and operability
testing of both the ET solenoid valve and the OPC solenoid valves isprudent.
Related Generic Communications
NUREG-1275, OperatingExperience Feedback Report - lenoid-Operated Valve
Problems, wh-lc was d1strlbuteto industry te
recent US. light-water reactor experience (primarily 1984-1989) with solenoid- operated valves (SOYs), Itwas found that most $0SY cannot tolerate contaminants, need preventative maintenance or periodic replacement and have 4 propensity
for rapid aging and deterioration when subjected to *e1vated temnperatures.
Various recommendations were provided to aid inthe prevention of further SOY
problems.
This information notice requires no specific action or written response. If
you have any questions about the information inthis notice please contact one
of the technical contacts listed below or the appropriate Office of Nuclear
Reactor Regulation project manager.
Charles E. Rossi, Director
Division of 0 eratlonal Events Assessment
Office of Nuc ear Reactor Regulation
Technical contacts: 4ohn White Region I
(215) 337.h114 David Gamberoni, NRA
(301) 492-1171
Attachmentss
1. List of Recently Issued NRC Informatlon Notices
oFr REUIONr I : AB;D0EAfNRR : SMERGION I ISCIEAB:DOE NRR
- --- ------ a..fi..' .sm.-----
NAME : f Moghissi : DGamberoni : MWhite : DFischor
- **bZ~~~~~~~-b----ttb---- ---- Pw ....,-.......-.-
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DATE tZ/5/91 //9t /191 : /91 OFU ..;EX9:D0EA-:NKRR
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BhE ......
C:tUiCBDOEANR9 1 DiDOEA:N(RR
NAME: AChaffee : CBerllnger : CRosW:
w.: ------.---- " * ..............
DATEz /191 1/91 /91 //91 OrricIAL RECORD COPY
Document Name IN91/$ALEM
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list | - Information Notice 1991-01, Supplier of Misrepresented Resistors (4 January 1991, Topic: Fitness for Duty)
- Information Notice 1991-02, Brachytherapy Source Management (7 January 1991, Topic: Fitness for Duty, Brachytherapy)
- Information Notice 1991-03, Management of Wastes Contaminated with Radioactive Materials (Red Bag Waste & Ordinary Trash) (7 January 1991, Topic: Fitness for Duty, Brachytherapy)
- Information Notice 1991-04, Reactor Scram Following Control Rod Withdrawal Associated with Low Power Turbine Testing (28 January 1991, Topic: Fitness for Duty)
- Information Notice 1991-05, Intergranular Stress Corrosion Cracking in Pressurized Water Reactor Safety Injection Accumulator Nozzles (30 January 1991, Topic: Fitness for Duty, Hydrostatic, Liquid penetrant)
- Information Notice 1991-06, Lock-up of Emergency Diesel Generator and Load Sequencer Control Circuits Preventing Restart of Tripped Emergency Diesel Generator (31 January 1991, Topic: Fitness for Duty, Brachytherapy)
- Information Notice 1991-07, Maintenance Deficiency Associated with General Electric Horizontal Custom 8000 Induction Motors (4 February 1991, Topic: Fitness for Duty, Brachytherapy)
- Information Notice 1991-08, Medical Examinations for Licensed Operators (5 February 1991, Topic: Brachytherapy)
- Information Notice 1991-09, Counterfeiting of Crane Valves (25 September 2007)
- Information Notice 1991-10, Summary of Semiannual Program Performance Reports on Fithess-For-Duty (FFD) in the Nuclear Industry (12 February 1991)
- Information Notice 1991-12, Potential Loss of Net Positive Suction Head (NPSH) of Standby Liquid Control System Pumps (15 February 1991)
- Information Notice 1991-13, Inadequate Testing of Emergency Diesel Generators (Edgs) (4 March 1991)
- Information Notice 1991-13, Inadequate Testing of Emergency Diesel Generators (EDGs) (4 March 1991)
- Information Notice 1991-14, Recent Safety-Related Incidents at Large Irradiators (5 March 1991, Topic: Fitness for Duty, Coatings, Incorporated by reference, Brachytherapy, Uranium Hexafluoride)
- Information Notice 1991-15, Incorrect Configuration of Breaker Operating Springs in General Electric AK-Series Metal-Clad Circuit Breakers (6 March 1991)
- Information Notice 1991-16, Unmonitored Release Pathways from Slightly Contaminated Recycle and Recirculation Water Systems at a Fuel Facility (6 March 1991, Topic: Fitness for Duty, Brachytherapy)
- Information Notice 1991-17, Fire Safety of Temporary Installation or Services (11 March 1991)
- Information Notice 1991-18, High-Energy Piping Failures Caused by Wall Thinning (18 December 1991)
- Information Notice 1991-19, Steam Generator Feedwater Distribution Piping Damage (12 March 1991)
- Information Notice 1991-20, Electrical Wire Insulation Degradation Caused Failure in a Safety-Related Motor Control Center (19 March 1991)
- Information Notice 1991-21, Inadequate Quality Assurance Program of Vendor Supplying Safety-Related Equipment (19 March 1991)
- Information Notice 1991-22, Four Plant Outage Events Involving Loss of AC Power or Coolant Spills (19 March 1991)
- Information Notice 1991-23, Accidental Radiation Overexposures to Personnel Due to Industrial Radiography Accessory Equipment Malfunctions (26 March 1991, Topic: Fitness for Duty, Brachytherapy)
- Information Notice 1991-24, Recent Operating Experience Involving Reactor Operation Without a Licensed Reactor Operator or Senior Reactor Operator Present in the Control Room (26 March 1991)
- Information Notice 1991-25, Commercial-Grade Structural Framing Components Supplied As Nuclear Safety-Related Equipment (1 April 1991)
- Information Notice 1991-25, Commercial-Grade Structural Framing Components Supplied as Nuclear Safety-Related Equipment (1 April 1991)
- Information Notice 1991-26, Potential Nonconservative Errors in the Working Format Hansen-Roach Cross-Section Set Provided with Keno and Scale Codes (2 April 1991, Topic: Fitness for Duty, Brachytherapy)
- Information Notice 1991-27, Incorrect Rotation of Positive Displacement Pump (10 April 1991)
- Information Notice 1991-28, Cracking in Feedwater System Piping (15 April 1991)
- Information Notice 1991-29, Deficiencies Identifie During Electrical Distribution System Functional Inspections (15 April 1991)
- Information Notice 1991-30, Inadequate Calibration of Thermoluminescent Dosimeters Utilized to Monitor Extremity Dose at Uranium Processing and Fabrication Facilities (23 April 1991, Topic: Brachytherapy, Uranium Hexafluoride)
- Information Notice 1991-31, Nonconforming Magnaflux Magnetic Particle (14AM) Prepared Bath (9 May 1991)
- Information Notice 1991-32, Possible Flaws in Certain Piping Systems Fabricated by Associated Piping and Engineering (15 May 1991, Topic: Hot Short, Liquid penetrant)
- Information Notice 1991-33, Reactor Safety Information for States During Exercises and Emergencies (31 May 1991)
- Information Notice 1991-34, Potential Problems in Identifying Causes of Emergency Diesel Generator Malfunctions (3 June 1991)
- Information Notice 1991-35, Labeling Requirements for Transporting Multi-Hazard Radioactive Materials (7 June 1991)
- Information Notice 1991-36, Nuclear Plant Staff Working Hours (10 June 1991)
- Information Notice 1991-37, Compressed Gas Cylinder Missile Hazards (10 June 1991)
- Information Notice 1991-38, Thermal Stratification in Feedwater System Piping (13 June 1991, Topic: Unanalyzed Condition)
- Information Notice 1991-39, Compliance with 10 CFR Part 21, Reporting of Defects and Noncompliance. (17 June 1991)
- Information Notice 1991-40, Contamination of Nonradioactive System and Resulting Possibility for Unmonitored, Uncontrolled Release to the Environment (19 June 1991)
- Information Notice 1991-41, Potential Problems with the Use of Freeze Seals (27 June 1991)
- Information Notice 1991-42, Plant Outage Events Involving Poor Coordination Between Operations and Maintenance Personnel During Valve Testing and Manipulations (27 June 1991)
- Information Notice 1991-43, Recent Incidents Involving Rapid Increases in Primary-To-Secondary Leak Rate (5 July 1991, Topic: Grab sample)
- Information Notice 1991-45, Possible Malfunction of Westinghouse Ard, Bfd, & Nbfd Relays, & A200 DC & DPC 250 Magnetic Contactors (5 July 1991)
- Information Notice 1991-46, Degradation of Emergency Diesel Generator Fuel Oil Delivery Systems (18 July 1991)
- Information Notice 1991-47, Failure of Thermo-Lag Fire Barrier Material to Pass Fire Endurance Test (6 August 1991, Topic: Safe Shutdown, Fire Barrier)
- Information Notice 1991-48, False Certificates of Conformance Provided by Westinghouse Electric Supply Company for Refurbished Commercial-Grade Circuit Breakers (9 August 1991, Topic: Fire Barrier)
- Information Notice 1991-49, Enforcement of Safety Requirements for Radiographers (15 August 1991, Topic: High Radiation Area, Fire Barrier)
- Information Notice 1991-50, a Review of Water Hammer Events After 1985 (20 August 1991, Topic: Fire Barrier)
... further results |
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