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June 20,, 1972 g
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l Mr. A. Giambusso Deputy Director, Reactor Projects U.S. Atomic Energy Commission Washington, D.C.
20545
Subject:
Quad-Cities Unit i Vibration Instrumentation
Dear Mr. Giambusso:
Several of the vibratica instruments contained in Quad-Cities Unit 1 reactor vessel have become unusable during the early stages of the'startup test program due to the various operations with the reactor vessel head.
The purpose of this letter is to inform you of the status of the vibration program ac Quad-cities Unit 1 and Commonwealth Edison's and Iowa-Illinois Gas and Electric's evaluation justifying the program with the remaining sensors.
The vibration program, as discussed in the Quad-Cities startup test instructions, utilizes acceleration and displacement sensors on the shroud, strain gages on two of the riser pipe brace and displacement sensors on two jet pumps.
The location and status of these sensors are tabulated below:
4 Location Status y
- 1. Shroud Acceleration sensors A-1 at 134 Good b7dh A-2 at 2240 Good O
Displacement sensor D-3 at 2280 Bad (o
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- 2. Riser Pipe on: Strain gages S1,S2,53 at 188 All bad Co Jet Pump On bottom side of S4,SS,56 at 212 64 bad, S5&S6 good Assembly riser brace
- 3. Jet Pump:
Displacement sensors on throat of Both good Jet pumps JP-11, JP-12 0
8709250450 870921 PDR FOIA MENZ87-111 PDR
Jommonwezith Edison Compai,.
6 Mr. A. Giambusso June 20, 1972 As indicated in Quad-Cities FSAR Amendment 13, Question /
Answer 3.3, Amendment 16, Question / Answer 3.4, and Amendment 19, General Electric Company has sufficient confidence in their overall vibration program for BWR's to consider any vibration program for Quad-cities to be superfluouar however, to be responsive to both AEC and ACRS concerns in this area, Commonwealth Edison Company, Iowa-Illinois Gas and Electric Ccapany and the General Electric Company agreed to provide a confirmatory vibration program for both units.
A detailed generic presentation was given to the AEC in San Jose, Californis on 5/12-13/71.
As was indicated at that time, all General Electric vibration programs have built-in redundancy designed to handle a certain amount of service losses expected for such sensitive instrumentation.
Since a critical factor which determines service losses ic the frequency with which the reactor vessel head is removed (thereby causing further movement of the sensitive instrument lines), limited losses of vibrction instrumentation were sustained when the reactor vessel head of Unit 1 was last removed to renew sources for startup.
a thorough investigation of the available vibration instrumentation has been made at Quad-cities.
The results of this I
investigation show that the initial program to measure two structural areas, the jet pump assembly and the shroud asrembly remains feasible.
An indicated previously, each of these assemblies was instrumented with redundancy because it was expected that all such instrumentation l
might not survive such occurrences as head removal or service testing.
Although some of this redundancy has been lost (i.e., instrumentation on one riser brace), both assemblies have confirmatory type instruments still functioning (i.e., shroud, one jet pump and one jet pump riser brace).
Additionally, Quad cities Unit 2 reactor vessel is instrumented like Quad-cities Unit 1 and measurements will be taken on Unit 2 in its startup test program which will be representative of Unit 1 and will assist in verifying the adequacy of the Unit 1 re stilta.
Dresden Unit 3 contained similar instrumentation with the exception that Dresden Unit 3 did not have a displacement sensor on the shroud.
The results of the Dresden Unit 3 vibratbn tests were satisfactory and will be part of the test program results submitted in accordance with the requirements of the Technical Specifications.
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June 20, 1972 Mr. A. Giambusso Thereforn, with the satisfactory results of Dresden Unit 3 and the startup test program scheduled for Quad-cities Unit 2, comanonwealth Edison Company and Iowa-Illinois Gas and Electric Company are satisfied that a ureful evaluation of the test can be made on Quad-Cities Unit 1 utilizing the remaining usuable vibration instruments. ;
No additional installation of-instruments or testing beyond the scope of the present test program is contemplated at this time.
Three originals and 19 copies are enclosed for your use.
Very truly yours,
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L. D. Butterfield, Jr.
Nuclear Licensing Administrator l
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