Morning Report for November 1, 1999
Headquarters Daily Report
NOVEMBER 01, 1999
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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 NOV. 01, 1999
Licensee/Facility: Notification:
Part 21 Database MR Number: H-99-0091
Engine Systems Date: 11/01/99
Subject: Part 21 - Questionable Soldering in Woodward EGM Controllers
Discussion:
VENDOR: Engine Systems PT21 FILE NO: 99-40-0
DATE OF DOCUMENT: 09/22/99 ACCESSION NUMBER: 9909290055
SOURCE DOCUMENT: LETTER REVIEWER: REXB, T. Koshy
NEW ISSUE. The vendor, Engine Systems, Inc., reports that Woodward type
EGM controllers manufactured between December 1997 and May 1999 may have
questionable soldering workmanship because of inadequate personnel
training. Such controllers are commonly used on turbine applications.
This issue was discovered by the Limerick licensee during visual
inspection of internal components of an EGM controller. Deficiencies
included wire strands, excessive solder flux (splash) and cold solder
connections. A listing of affected customers, part numbers, and serial
numbers is given at
http://www.nrc.gov/NRC/PUBLIC/PART21/1999/1999400.html
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HEADQUARTERS MORNING REPORT PAGE 2 NOVEMBER 1, 1999
Licensee/Facility: Notification:
Part 21 Database MR Number: H-99-0092
Abb Date: 11/01/99
Subject: Part 21 - Tripper Paddle Interference
in ABB K-Line Circuit Breaker
Discussion:
VENDOR: ABB PT21 FILE NO: 99-41-0
DATE OF DOCUMENT: 09/23/99 ACCESSION NUMBER:
SOURCE DOCUMENT: EN 36218 REVIEWER: REXB, D. Skeen
NEW ISSUE. The Summer licensee reports that a refurbished K-Line circuit
breaker, manufactured and refurbished by ABB, failed to trip because the
shunt trip wires interfered with the red tripper paddle on the left side
of the breaker. Other ABB K-Line breakers at the plant had the wires
routed in a different direction, precluding interference with the paddle.
On October 18, 1999, the licensee and vendor reported results of their
inspection of 26 safety-related and 3 nonsafety-related breakers. One
safety-related breaker was found to be affected and another
safety-related breaker potentially affected. They determined that the
following information should be provided to all licensees regarding this
issue.
Potentially affected ABB K-line breakers are of the following types:
1. All electrically-operated breakers with model numbers K-1600,
K-1600S, K-2000, K- 2000S, and K-225 through K-800
2. Any mechanically- or electrically-operated breakers with the above
model numbers that have auxiliary switches or shunt trip
A trip-free condition, with respect to the overload trip function, could
result for breakers having the shunt trip coil wiring on top of the
tripper paddle. The overload trip could be prevented for breakers having
the shunt trip coil wiring underneath the tripper paddle. The licensee
corrected the problem by securing any wiring that could interfere with
the proper operation of the tripper paddle.
This problem is not limited to the breaker refurbishment or repair
process by ABB Service. The licensee stated that this condition could
occur on new breakers.
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HEADQUARTERS MORNING REPORT PAGE 3 NOVEMBER 1, 1999
Licensee/Facility: Notification:
Part 21 Database MR Number: H-99-0093
Swagelok Date: 11/01/99
Subject: Part 21 - Potential Crack in Tube Fitting Seat
Discussion:
VENDOR: Swagelok PT21 FILE NO: 99-42-0
DATE OF DOCUMENT: 10/06/99 ACCESSION NUMBER:
SOURCE DOCUMENT: EN 36263 REVIEWER: REXB, R. Benedict
NEW ISSUE. The vendor, Swagelok Company, reports a possible defect in
tube fitting part number SS-400-3-4TTM, male branch tee. The defect is a
crack in the seat of the fitting. Swagelok is continuing its analysis.
Affected nuclear power plants include Vogtle, Oconee, Palo Verde,
Seabrook, Surry, and Ft. Calhoun.
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HEADQUARTERS MORNING REPORT PAGE 4 NOVEMBER 1, 1999
Licensee/Facility: Notification:
Part 21 Database MR Number: H-99-0094
Brand Rex Date: 11/01/99
Subject: Part 21 - Damaged Safety-Grade Electrical
Cabling Found in Supply
Discussion:
VENDOR: Brand Rex PT21 FILE NO: 99-43-0
DATE OF DOCUMENT: 10/06/99 ACCESSION NUMBER:
SOURCE DOCUMENT: EN 36265 REVIEWER: REXB, C. Petrone
NEW ISSUE. The Crystal River licensee reports finding damaged insulation
on the same conductor in each of six samples of three-conductor cable
(BICC Brand Rex Company power cable #1108582, 1 kV, 3/C, #2/0, Class B,
90C,XLPE Insulated, Black Jacket). The licensee was installing this
cable, procured as safety-grade and environmentally qualified cable, in a
nonsafety-related application. The licensee found the damage on removing
the outer jacket for termination. The licensee learned from the vendor,
Brand Rex, that during cable fabrication, while combining the three
conductors before closing, the damaged conductor fell off the cabling
unit pulley due to loss of tension, causing the insulation to be scraped.
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HEADQUARTERS MORNING REPORT PAGE 5 NOVEMBER 1, 1999
MR Number: H-99-0095
NRR DAILY REPORT ITEM
SIGNIFICANT EVENTS
Subject: Electrical Transient and Forced Outage at Beaver Valley, Unit 2,
Classified As A Significant Event
The Beaver Valley, Unit 2, July 16, 1999 event is classified as a
Significant Event for the Performance Indicator Program. This
classification is based on the degradation of the important safety
systems that were revealed in this event as deficiencies in design,
maintenance and operational area.
During Emergency Diesel Generator (EDG) #2 test, while loaded to the
safety bus, the bus supply breaker tripped and de-energized one train of
the 4160v safety bus. This trip resulted in loss of thermal barrier heat
exchanger cooling for two reactor coolant pumps (RCPs) and loss of seal
cooling for all three reactor coolant pumps. In the absence of any
systematic priority determination, the operators resolved to establish
seal injection when 120 alarms were lit in the control room. The seal
injection was established in less than three minutes, and the loss of all
RCP cooling was not recognized by the operators until 15 minutes into the
event. The annunciator response procedure for loss of seal injection
would have directed the operator to trip the reactor immediately and the
RCPs in two minutes with a concurrent loss of thermal barrier heat
exchanger cooling. Operation of the RCPs without cooling could have led
to a RCP seal LOCA.
The de-energized safety bus disabled two battery chargers that supported
two instrument channels of the safety grade dc buses. The licensee lacked
procedures to recover the 4160v safety bus from abnormal conditions which
partially influenced the bus recovery time of two hours. The batteries
for the two instrument channels continued to deplete from the operational
loads during these two hours. A subsequent equalizing charge for two
hours brought one of the batteries only to the technical specification
allowable value. Continued degradation of the dc buses could have
hindered 4160v safety bus recovery.
Two days before the electrical event, service water cooling to EDG #2 was
significantly degraded (below its design basis value) after a chemical
treatment was applied to prevent macro biological fouling (bio-fouling).
After the plant had been shutdown, a second chemical treatment of the
service water system resulted in the rapid degradation of service water
flow to EDG #1. It was later revealed that a fortuitous personnel error
was the only reason the initial chemical treatment did not affect both
EDGs simultaneously.
The licensee's bio-fouling treatment program had the potential to cause a
common mode failure of all on-site emergency AC power. A later licensee
calculation concluded that the actual flow was sufficient for heat
removal for the river water temperatures that existed at the time.
The Beaver Valley #2 design that disabled both of the RCP cooling systems
HEADQUARTERS MORNING REPORT PAGE 6 NOVEMBER 1, 1999
MR Number: H-99-0095 (cont.)
on loss of one safety bus, exposed the vulnerability for a seal LOCA on
two RCPs. Lack of operator training to identify time critical duties
increased the duration of the vulnerability for a seal failure. A
critical safety bus with a full train of emergency core cooling systems
remained unavailable for more than two hours during this plant transient.
The licensee has estimated a conditional core damage probability of
2.8E-6 based on the conclusion that the emergency diesel generators
remained operable.
Contact: Thomas Koshy, REXB
301-415-1176
Email:
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