ML053550033
| ML053550033 | |
| Person / Time | |
|---|---|
| Site: | University of Missouri-Columbia |
| Issue date: | 12/12/2005 |
| From: | Foyto L Univ of Missouri - Columbia |
| To: | Alexander Adams Office of Nuclear Reactor Regulation |
| References | |
| Download: ML053550033 (5) | |
Text
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V 1A-A up Research Reactor Center University of Missouri-Columbia Research Park Columbia, MO 65211 PHONE (573) 8824211 FAX (573) 882-6360 December 12, 2005 Mr. Alexander Adams, Jr.
U.S. Nuclear Regulatory Commission Mail Stop 012-G13 Washington, DC 20555-0001
REFERENCE:
SUBJECT:
Docket No. 50-186 University of Missouri-Columbia Research Reactor Amended Facility License R-103 MURR Operations Monthly Summary
Dear Mr. Adams:
Enclosed is a copy of MURR's Monthly Operations Summary for November 2005. If you have any questions, please contact me at (573) 882-5276.
Sincerely, Reactor Manager LPF/djr Enclosure (D
AN EQuAL oppoRTONITrY/ADA I N SlUIYION
UNIVERSITY OF MISSOURI RESEARCH REACTOR OPERATIONS MONTHLY
SUMMARY
November 2005 Prepared by:
Operations Staff
INTRODUCTION The reactor operated continuously in November with the following exceptions:
4 shutdowns for scheduled maintenance and refueling; 4 unscheduled power reductions.
MAINTENANCE ACTIVITIES 11/2/05 Refueled - removed core 05-54, loaded core 05-55.
Shortened the cabling on Control Rod 'C' Drive Mechanism Electro-Magnet.
Replaced the vibration switch on Cooling Tower Fan CTF-2 motor.
11/6/05 Refueled - removed core 05-55, loaded core 05-56.
Replaced the Reactor Safety System "Green Leg" Trip Actuator Amplifier.
11/7/05 Refueled - removed core 05-56, loaded core 05-57.
11/14/05 Refueled - removed core 05-57, loaded core 05-58.
Loaded new pool de-ionization bed 'F.'
11/15/05 Replaced the pressure switch for the Facility Main Air compressor.
11/16/05 Shipped eight spent fuel elements to Savannah River Site.
11/21/05 Refueled - removed core 05-58, loaded core 05-59.
Completed Modification Record 05-09 (Redirect Resin Sluice Water to Waste Tanks).
11/25/05 Refueled - removed core 05-59, loaded core 05-60.
Replaced the Rod Run-In Trip Actuator Amplifier.
11/28/05 Refueled - removed core 05-60, loaded core 05-61.
Flooded Beamport 'C' with demineralized water.
Replaced the level switch in Waste Tank 4.
Replaced the harmonic filter on Secondary Coolant System Pump SP-1.
Page 2 of 3
UNSCHEDULED POWER REDUCTIONS Date No.
Tvpe Cause 11/2/05 1191 Rod Run-In Rod Not In Contact With Magnet On November 2, a "Rod Not In Contact With Magnet Rod Run-In" was automatically initiated when control blade "C" anvil separated from its magnet during a routine outward shimming evolution. The reactor was shutdown and the pull rod to housing alignment was checked and verified satisfactory. During the October 31 maintenance day activities, the electromagnet cabling for Control Rod 'C' Drive Mechanism was replaced due to degradation of the cabling insulation. In comparison to the other Drive Mechanisms, it appeared that the new cabling was longer than the others. This may have caused the cabling to "bunch up" as the drive tube retracted into the upper housing. The cabling was shortened approximately 6-inches and the control rod was satisfactorily withdrawn to the full out position asspart of the retest. The reactor was refueled and subsequently returned to 10 MW operation.
11/6/05 1192 Rod Run-In Rod Not In Contact With Magnet On November 6, a "Rod Not In Contact With Magnet Rod Run-In" was automatically initiated when control rods 'C' and 'D' separated from their electromagnets. It was immediately noted by the reactor operator that the Trip Actuator Amplifier (TAA) for the "Green Leg" of the Reactor Safety System had tripped. Troubleshooting efforts revealed not specific cause and the condition could not be re-created. As a precaution, the TAA was replaced with one from spares. Further bench-top testing will be performed. The reactor was refueled and subsequently returned to 10 MW operation.
11/25/05 1193 Rod Run-In Failure of Trip Actuator Amplifier On November 25, the reactor was shutdown when all four control rods automatically inserted by rod run-in for no apparent reason. Troubleshooting efforts revealed that the Rod Run-In Trip Actuator Amplifier (TAA) had failed and could not be reset. Bench-top testing discovered two failed transistors. The TAA was replaced with one from spares, it was tested satisfactory, and the reactor was refueled and subsequently returned to 10 MW operation.
11/28/05 1194 Scram Pool Loop Valve 509 Off Open On November 28, a "Pool Loop Valve 509 Off Open" scram was automatically initiated during a reactor startup (the reactor was still subcritical). Valve 509 position indication on the Instrument Panel indicated that the valve was open and the scram condition immediately cleared.
Additionally, had the valve actually come off of its open seat, the pool coolant system pumps would have secured as part of the valve-pump interlock circuitry. The most probable cause was either dirt between the contact surfaces or the contact had not properly seated during system startup causing a momentary break in connectivity. All contacts on the relay block were burnished and the relay was manually cycled to ensure freedom of movement. All retesting indicated proper operation of the relay and its contacts, and the reactor was refueled and subsequently returned to 10 MW operation.
Page 3 of 3
-4 Nov OPERA77ON
SUMMARY
FOR MONTH OF University of Missour Research Reactor Center (MURR)
HOURS OPERATED THIS PERIOD TOTAL HOURS OPERATED, REACTOR HOURS OPERATED AT FULL POWER, THIS PERIOD TOTAL HOURS AT FULL POWER, REACTOR INTEGRATED POWER THIS PERIOD TOTAL INTEGRATED POWER, REACTOR I
NOV-05 l
1 634.85 1 270,329.10 1
631.52 1
l 266,950.66 l
263.28 l MWD l
105,432.29 lMWD Submitted by: -
- D' 6Ls MWD Custodian/Reactor Physicist D21
/ l Date: