Morning Report for May 29, 2001
Headquarters Daily Report
MAY 29, 2001
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REPORT NEGATIVE NO INPUT
ATTACHED INPUT RECEIVED RECEIVED
HEADQUARTERS X
REGION I X
REGION II X
REGION III X
REGION IV X
PRIORITY ATTENTION REQUIRED MORNING REPORT - HEADQUARTERS MAY 29, 2001
Licensee/Facility: Notification:
Part 21 Database MR Number: H-01-0036
Abb Automation Date: 05/29/01
Subject: Part 21 - Broken base for two telephone relays in Class 1E
type CV-7 relay
Discussion:
VENDOR: ABB Automation PT21 FILE NO: m1-16-0
DATE OF DOCUMENT: 04/10/01 ACCESSION NUMBER: ML011130015
SOURCE DOCUMENT: LETTER REVIEWER: REXB, R. Telson
The vendor ABB Automation reported a potential defect in its Class 1E
type CV-7 relay. In November of 1999 Duke Energy Corporation returned
four such relays that had cracked or broken bases for the plastic
pedestal used to mount a plate retaining two telephone relays. The vendor
concluded the cause of failure was "shipping damage." The vendor
redesigned the telephone relay mounting plate. The affected styles are
1454C77A02, A08, and A11. The vendor states that it will notify and
instruct all its affected customers to visually inspect the product and
return it to the vendor for repair if required. The NRC will post ensuing
reports on this subject on its Web site at
http://www.nrc.gov/NRC/PUBLIC/PART21/2001.
Contact: R. Telson, NRR 301-415-1175
E-mail: rdt@nrc.gov
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HEADQUARTERS MORNING REPORT PAGE 2 MAY 29, 2001
Licensee/Facility: Notification:
Part 21 Database MR Number: H-01-0037
Framatome Anp Date: 05/29/01
Subject: Part 21 - Calculation of time to criticality for a boron
dilution event
Discussion:
VENDOR: Framatome ANP PT21 FILE NO: m1-17-0
DATE OF DOCUMENT: 04/27/01 ACCESSION NUMBER: ML011200457
SOURCE DOCUMENT: LETTER REVIEWER: REXB, E. Goodwin
The vendor Framatome ANP reported that for reactor coolant flow rates
near the lower end of the flow range of the shutdown cooling system, use
of the instantaneous mixing model, which assumes a completely mixed
coolant volume, may lead to a non-conservative prediction of the time to
criticality for a boron dilution event. If a completely mixed coolant
volume cannot be assumed, then the dilution front model is used to
evaluate the adequacy of margin to criticality. For high flow rates, the
calculated times to criticality from the initiation of a boron dilution
event are about the same for both models but for low flow rates, they may
be significantly different. A quantitative flow criterion has not been
established for choosing between these models.
In the instantaneous mixing model, unborated water injected into the
reactor coolant system is assumed to mix instantaneously with an
effective system volume. The change in core boron concentration with time
is continuous and homogeneous, corresponding to the increasing amount of
dilution water entering the reactor coolant system.
In the dilution front model, unborated water injected into the reactor
coolant system is assumed to mix with a slug of borated water at the
injection point. The diluted slug is assumed to move through the reactor
core and around the reactor coolant system. The change In core boron
concentration with time depends on the location of the diluted slug.
The vendor states that it notified customers potentially affected by this
issue, drafted a flow criterion that supports the use of the
instantaneous mixing model in those current analyses where it has been
used, and continues to evaluate the criterion.
The NRC will post ensuing reports on this subject on its Web site at
http://www.nrc.gov/NRC/PUBLIC/PART21/2001.
Contact: E. Goodwin, NRR
301-415-1154
E-mail: efg@nrc.gov
HEADQUARTERS MORNING REPORT PAGE 3 MAY 29, 2001
MR Number: H-01-0037 (cont.)
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HEADQUARTERS MORNING REPORT PAGE 3 MAY 29, 2001
Licensee/Facility: Notification:
Part 21 Database MR Number: H-01-0038
Abb Power Date: 05/29/01
Subject: Part 21 - Failure of K-Line circuit breaker to close because
of a malfunctioning hairpin retainer
Discussion:
VENDOR: ABB Power PT21 FILE NO: m1-18-0
DATE OF DOCUMENT: 05/02/01 ACCESSION NUMBER:
SOURCE DOCUMENT: EN 37961 REVIEWER: REXB, V. Hodge
The vendor ABB Power Distribution reported a failure to close of a K-Line
circuit breaker during service testing due to a malfunctioning
replacement control device. The retainer on the close coil armature pivot
pin becomes dislodged from its slot, allowing the pin to "wander" from
the proper position inside the armature. The vendor states that this part
was subject of a design change in November 1998. To facilitate assembly,
hairpin retainer part number 53152C00 was changed to 53152D00 in K-Line
708392T## series control device assemblies. This issue only affects
K-Line circuit breakers with a mechanical "black box" control device
containing an internal close coil and purchased between November 1998 and
February 15, 2001.
The vendor states this design change was reversed on February 16, 2001,
and that affected assembly personnel have been trained. The vendor
recommends repairing or replacing these control devices as soon as
feasible and states that it will notify all customers who purchased this
product.
The NRC will post ensuing reports on this subject on its Web site at
http://www.nrc.gov/NRC/PUBLIC/PART21/2001.
Contact: V. Hodge, NRR
301-415-1861
E-mail: cvh@nrc.gov
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HEADQUARTERS MORNING REPORT PAGE 4 MAY 29, 2001
Licensee/Facility: Notification:
Part 21 Database MR Number: H-01-0039
Inovision Date: 05/29/01
Subject: Part 21 - Spiking R-11 radiation monitor output
Discussion:
VENDOR: Inovision PT21 FILE NO: m1-19-0
DATE OF DOCUMENT: 05/11/01 ACCESSION NUMBER:
SOURCE DOCUMENT: EN 37985 REVIEWER: REXB, C. Petrone
The vendor Inovision (formerly Victoreen and Keithley Radiation
Measurements) reports a potential defect in its R-11 radiation monitor.
The problem, a rapid increase (spiking) in displayed concentration and
analog output values for activity in the upper range that may render the
instrument inoperable, is believed due to microprocessor inability to
read and clear a register in the allotted time. The vendor believes this
problem only affects Model 960 firmware modules upgraded or purchased
since 1992 and expects to complete its evaluation by July 10, 2001.
The NRC will post ensuing reports on this subject on its Web site at
http://www.nrc.gov/NRC/PUBLIC/PART21/2001.
Contact: C. Petrone, NRR 301-415-1027
E-mail: cdp@nrc.gov
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REGION I MORNING REPORT PAGE 5 MAY 29, 2001
Licensee/Facility: Notification:
Niagara Mohawk Power Corp. MR Number: 1-01-0014
Nine Mile Point 2 Date: 05/25/01
Lycoming,New York
Dockets: 50-410
BWR/GE-5
Subject: MAY 24, 2001 REACTIVITY TRANSIENT
Reportable Event Number: 38033
Discussion:
Licensee investigation identified that the cause of the May 24, 2001, 'B'
recirculation flow control valve (FCV) malfunction and subsequent
reactivity transient was a failed radial variable differential
transformer (RVDT) in the valve position indication/feedback control
circuit (located inside the drywell). Upon confirmation of the RVDT
failure, the recently installed alternate position indicating/feedback
circuit for both recirculation FCVs was placed in-service. Following a
station operations review committee examination of the post-transient
analysis and critique, the unit was returned to full power operations on
May 28. The licensee plans to continue operations with the alternate
circuit as the primary FCV position indication and feedback control
circuit.
Licensee analysis, as well as, independent review by the Global Nuclear
Fuels, confirmed that all safety systems functioned as designed and that
no thermal or mechanical design limits were exceeded. Review of the
installed transient analysis recording system data identified that
indicated neutron flux ranged between 117 and 61 percent, until the
operators were able to lock- up the FCV and stabilize recirculation flow.
Maximum simulated thermal power during the transient was determined to be
approximately 102 percent (reference Event No. 38033). Detailed review
of the reactor protection system response, including back-up calculations
of flow biased rod block and trip setpoints, confirmed that no protective
limits were exceeded during the transient.
The resident inspectors were assisted by a region based inspector in
reviewing the operators' response to the transient and the licensee's
detailed analysis of the event prior to resumption of full power
operations.
Contact: William Cook (610)337-5074
Michelle Evans (610)337-5224
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Page Last Reviewed/Updated Wednesday, March 24, 2021
Page Last Reviewed/Updated Wednesday, March 24, 2021