Information Notice 1989-38, Atmospheric Dump Valve Failures at Palo Verde Units 1, 2, and 3
UNITED STATES NUCLEAR REGULATORY
COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C. 20555 April 5, 1989 INFORMATION
NOTICE NO. 89-38: ATMOSPHERIC
DUMP VALVE FAILURES AT PALO VERDE UNITS 1, 2, AND 3
Addressees
All holders reactors.of operating
licenses or construction
permits for nuclear power
Purpose
- This information
notice is being provided to alert addressees
to potential failures of main steamline
atmospheric
dump valves (ADVs). It is expected that recipients
will review the information
for applicability
to their facil-ities and consider actions, as appropriate, to avoid similar problems.
However, suggestions
contained
in this information
notice do not constitute
NRC require-ments; therefore, no specific action or written response is required.Description
of Circumstances:
On March 3, 1989, Palo Verde Unit 3 experienced
a large load rejection
and a subsequent
automatic
reactor power decrease from 98 percent to 45 percent power.The turbine bypass valves opened but the bypass valve controller
malfunctioned, causing excessive
steam relief and overcooling
of the reactor coolant system (RCS). A main steamline
isolation
and reactor trip were caused by low pressure in the number 2 steam generator.
Safety injection
and containment
isolation activated
upon low RCS pressure.
Following
steamline
isolation, the ADVs remained closed after operators
attempted
to open them first from the control room and then from the remote shutdown panel. The valves do not receive an automatic
signal to open. After the ADVs failed to open remotely, auxiliary operators
experienced
difficulty
in opening the ADVs using the handwheels
because of the lack of lighting (including
emergency
lighting), poor labeling of ADV equipment, poor procedures
and training, a disengaged
handwheel, and considerable
noise caused by the opening of the main steamline
safety relief valves. The operators
partially
opened two ADVs.The pneumatic
operators
on the ADVs are actuated by using either plant instru-ment air or a stored, pressurized
nitrogen supply. The valves were manufactured
by Control Components, Inc. (CCI). CCI indicated
that previous problems had been experienced
in the testing of ADVs at Palo Verde Unit 1 and other facil-ities. Excessive
bonnet pressure caused by abnormally
high leakage past the main valve plug piston ring is suspected
to have contributed
to these problems.Foreign particles
from the steamlines
in the clearance
areas and under the piston ring sealing surfaces may produce the high piston ring leakage. CCI has developed
design modifications
to address this problem. X'/V ( 8903300021 Z4-j),11 ~ -~ _i
IN 89-38 April 5, 1989 Following
the failures of the ADVs to open remotely at Palo Verde Unit 3, the licensee tested the ADMs at the other two Palo Verde units. Four of the eight valves failed the functional
tests. Preliminary
results indicated
that there were problems with valve positioners, possible valve stem binding problems, and calibration
problems with nitrogen pressure regulators.
The licensee for Palo Verde is continuing
to investigate
the cause of valve failures but has not yet identified
a root cause.Contributing
to the simultaneous
ADV failures at Palo Verde is the lack of in-service testing under hot steam conditions.
The valves are routinely
tested during refueling
outages with the steamlines
cold and depressurized.
For testing, the pneumatic
operators
are actuated with plant air rather than with the pressurized
nitrogen supply.Licensees
may wish to reassess the frequency
of ADV testing and to evaluate their ADV surveillance
test procedures
and consider performing
the tests under conditions
that better simulate inservice
conditions.
No specific action or written response is required by this information
notice.If you have any questions
about this matter, please contact one of the technical contacts listed below or the Regional Administrator
of the appropriate
regional office.Charles E. Ross,, Director Division of Operational
Events Assessment
Office of Nuclear Reactor Regulation
Technical
Contacts:
Horace Shaw, NRR (301) 492-0906 Walton Jensen, NRR (301) 492-1190 Attachment:
List of Recently Issued NRC Information
Notices
IN 89-38 April 5, 1989 Following
the failures of the ADVs to open remotely at Palo Verde Unit 3, the licensee tested the ADYs at the other two Palo Verde units. Four of the eight valves failed the functional
tests. Preliminary
results indicated
that there were problems with valve positioners, possible valve stem binding problems, and calibration
problems with nitrogen pressure regulators.
The licensee for Palo Verde is continuing
to investigate
the cause of valve failures but has not yet identified
a root cause.Contributing
to the simultaneous
ADV failures at Palo Verde is the lack of in-service testing under hot steam conditions.
The valves are routinely
tested during refueling
outages with the steamlines
cold and depressurized.
For testing, the pneumatic
operators
are actuated with plant air rather than with the pressurized
nitrogen supply.Licensees
may wish to reassess the frequency
of ADV testing and to evaluate their ADV surveillance
test procedures
and consider performing
the tests under conditions
that better simulate inservice
conditions.
No specific action or written response is required by this information
notice.If you have any questions
about this matter, please contact one of the technical contacts listed below or the Regional Administrator
of the appropriate
regional office.Charles E. Rossi, Director Division of Operational
Events Assessment
Office of Nuclear Reactor Regulation
Technical
Contacts:
Horace Shaw, NRR (301) 492-0906 Walton Jensen, NRR (301) 492-1190 Attachment:
List of Recently Issued NRC Information
Notices*SEE PREVIOUS CONCURRENCE
- EAB:NRR *EAB:NRR *TECH:ED *DEST/EMEB
- EMEB:NRR
- AD:EMEB:NRR
WJensen:db
RLobel HShaw LBMarsh JERichardson
3/27/89 3/27/89 / /89 3/28/89 3/28/89 3/28/89*D:DEST *C:EAB:NRR
- C:OGCB:NRRD
4 IR/>LShao WDLanning
CHBerlinger
eUoI'l3/29/89 3/29/89 3/29/89 3 /70/89 IN 89-April 1989 Following
the failures of the ADVs to open remotely at Palo Verde Unit 3, the licensee tested the ADYs at the other two Palo Verde units. Four of the eight valves failed the functional
tests. Preliminary
results indicated
that there were problems with valve positioners, possible valve steam binding problems, and calibration
problems with nitrogen pressure regulators.
The licensee for Palo Verde is continuing
to investigate
the cause of valve failures but has not yet identified
a root cause.Contributing
to the simultaneous
ADV failures at Palo Verde is the lack of in-service testing under hot steam conditions.
The valves are routinely
tested during refueling
outages with the steamlines
cold and depressurized.
For testing, the pneumatic
operators
are actuated with plant air rather than with the pressurized
nitrogen supply.Licensees
may wish to reassess the frequency
of ADY testing and to evaluate their ADV surveillance
test procedures
and consider performing
the tests under conditions
that better simulate inservice
conditions.
No specific action or written response is required by this information
notice. If you have any questions
about this matter, please contact one of the technical
contacts listed below or the Regional Administrator
of the appropriate
regional office.Charles E. Rossi, Director Division of Operational
Events Assessment
Office of Nuclear Reactor Regulation
Technical
Contacts:
Horace Shaw, NRR (301) 492-0906 Walton Jensen, NRR (301) 492-1190 Attachment:
List of Recently Issued NRC Information
Notices*SEE PREVIOUS CONCURRENCE
- EAB:NRR *EAB:NRR *TECH:ED *DEST/EMEB
- EMEB:NRR
- AD:EMEB:NRR
WJensen:db
RLobel HShaw LBMarsh JERichardson
/ /89 / 89 /1 / /89 / /89 / /89*D:DEST C: C:O-CB NRR D:DOEA:NRR
LShao Wti0nniRng
CHBerlinger
CERossi/ /89 i'9 Y89 3 b/89 / /89 IN 89-April , 1989 Following
the failures of the ADVs to open remotely at Palo Verde Unit 3, the licensee tested the ADYs at the other two Palo Verde units. Four of the eight valves failed the functional
tests. Preliminary
results indicated
that there were problems with valve positioners, sizing of nitrogen accumulators, and a failure of and calibration
problems with nitrogen pressure regulators.
The licensee for Palo Verde is continuing
to investigate
the cause of valve failures but has not yet identified
a root cause.Contributing
to the simultaneous
ADY failures at Palo Verde is the lack of in-service testing under hot steam conditions.
The valves are routinely
tested with the steamlines
cold and depressurized.
For testing, the pneumatic operators
are activated
with plant air rather than with the pressurized
nitrogen supply.Licensees
may wish to evaluate their ADY surveillance
test procedures
and consider performing
the tests under conditions
that better simulate inservice conditions.
No specific action or written response is required by this information
notice. If you have any questions
about this matter, please contact one of the technical
contacts listed below or the Regional Administrator
of the appropriate
regional office.Charles E. Rossi, Director Division of Operational
Events Assessment
Office of Nuclear Reactor Regulation
Technical
Contacts: Horace Shaw, NRR (301) 492-0906 Walton Jensen, NRR (301) 492-1190 List of Recently Issued NRC Information
Not Attachment:
- i ces AD: XEihRR dD:DEST JERichardso#JlShao
)/ U4/89 -\ /N>89*SEE PREVIOUS CONCURRENCE
- EAB:NRR *EAB:NRR *TECH:ED WJensen:db
RLobel/ /89 / /89 / /89 DEST/EM*EP
HShaw O V A--'Y89 EMEB:NRR LBMarsh'3 /.7/89 C:EAB:NRR WDLanning/ /89 C:OGCB:NRR
CHBerlinger
/ /89 D:DOEA:NRR
CERossi/ /89 IN 89-April I 1989 Following
the failures of the ADYs to open remotely at Palo Verde Unit 3, the licensee tested the ADVs at the other two Palo Verde units. Four of the eight valves failed the functional
tests. Preliminary
results indicated
that there were problems with valve positioners, sizing of nitrogen accumulators, and a failure of and calibration
problems with nitrogen pressure regulators.
The licensee for Palo Verde is continuing
to investigate
the cause of valve failures but has not yet identified
a root cause.Contributing
to the simultaneous
ADV failures at Palo Verde is the lack of in-service testing under hot steam conditions.
The valves are routinely
tested with the steamlines
cold and depressurized.
For testing, the pneumatic operators
are activated
with plant air rather than with the pressurized
nitrogen supply.Licensees
may wish to evaluate their ADV surveillance
test procedures
and consider performing
the tests under conditions
that better simulate inservice conditions.
No specific action or written response is required by this information
notice. If you have any questions
about this matter, please contact one of the technical
contacts listed below or the Regional Administrator
of the appropriate
regional office.Charles E. Rossi, Director Division of Operational
Events Assessment
Office of Nuclear Reactor Regulation
Technical
Contacts:
Horace Shaw, NRR (301) 492-0906 Walton Jensen, NRR (301) 492-1190 Attachment:
List of Recently Issued NRC Information
Notices*SEE PREVIOUS CONCURRENCE
- EAB:NRR *EAB:NRR *TECH:ED DEST/EMER
D:DEST iMEB:NRR AD:EMEB:NRR
WJensen:db
RLobel HShaw LShao LBMarsh JERichardson
/ /89 / /89 / /89 3/X7/89 / /89 3 /4/89 / /89 C:tAB:NRR
C:OGCB:NRR
D:DOEA:NRR
WDLanning
CHBerlinger
CERossi/ /89 / /89 / /89 IN 89-April , 1989 Following
the failures of the ADVs to open remotely at Palo Verde Unit 3, the licensee tested the ADYs at the other two Palo Verde units. Four of the eight valves failed the functional
tests. Preliminary
results indicated
that there were problems with valve positioners, sizing of nitrogen accumulators, and a failure of and calibration
problems with nitrogen pressure regulators.
The licensee for Palo Verde is continuing
to investigate
the cause of valve failures but has not yet identified
a root cause.Contributing
to the simultaneous
ADV failures at service testing under hot steam conditions.
The with the steamlines
cold and depressurized.
For tuators are energized
with plant air rather than supply.Palo Verde is the lack of in-valves are routinely
tested testing, the pneumatic
ac-with the pressurized
nitrogen Licensees
may wish to evaluate their ADV surveillance
test procedures
and consider performing
the tests under conditions
that better simulate inservice conditions.
No specific action or written response is required by this information
notice. If you have any questions
about this matter, please contact one of the technical
contacts listed below or the Regional Administrator
of the appropriate
regional office.Charles E. Rossi, Director Division of Operational
Events Assessment
Office of Nuclear Reactor Regulation
Technical
Contacts: Horace Shaw, NRR (301) 492-0906 Walton Jensen, NRR (301) 492-1190 Attachment:
List of Recently Issued NRC Information
Notices EAB EABdZV TECH:ED WJensen RLobel S3/Z7/89 5/Z7/89 / /89 DEST/EMEB HShaw/ /89 D:DEST LShao/ /89 C:EAB: NRR'DLanning/ /89 C:OGCB:NRR
CHBerlinger
/ /89 D:DOEA:NRR
CERossi/ /89
..I I Attachment
IN 89-38 April 5, 1989 LIST OF RECENTLY ISSUED NRC INFORMATION
NOTICES Information
Date of Notice No. Subject Issuance Issued to 89-37 89-36 88-86, Supp. 1 89-35 89-34 89-33 89-32 89-31 89-30 Proposed Amendments
to 40 CFR Part 61, Air Emission Standards for Radionuclides
Excessive
Temperatures
in Emergency
Core Cooling System Piping Located Outside Containment
Operating
with Multiple Grounds in Direct Current Distribution
Systems Loss and Theft of Un-secured Licensed Material Disposal of Americium Well-Logging
Sources Potential
Failure of Westinghouse
Tube Mechanical
Plugs Surveillance
Testing of Low-Temperature
Overpressure-Protection
Systems Swelling and Cracking of Hafnium Control Rods High Temperature
Environments
at Nuclear Power Plants 4/4/89 4/4/89 3/31/89 3/30/89 3/30/89 3/23/89 3/23/89 3/22/89 3/15/89 All U.S. NRC licensees.
All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All U.S. NRC byproduct, source and special nuclear material licensees.
All holders of an NRC specific license authorizing
well-logging activities.
All holders of OLs or CPs for PWRs.All holders of OLs or CPs for PWRs.All holders of OLs or CPs for PWRs with Hafnium control rods.All holders of OLs or CPs for nuclear power reactors.OL = Operating
License CP -Construction
Permit