ML20211G996
| ML20211G996 | |
| Person / Time | |
|---|---|
| Site: | Byron  |
| Issue date: | 10/29/1986 |
| From: | Ainger K COMMONWEALTH EDISON CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| 2324K, NUDOCS 8611040358 | |
| Download: ML20211G996 (3) | |
Text
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CORNRORWGSltll EdlSINI One First Nabonal Plaza. Chaca00, IEnois C
m f Address Reply to: Post Omco Box 767 Chicago,IEnois 60600 0767 October 29, 1986 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
Byron Station Unit 2 Preservice Inspection Steam Generators and Pressurizer NRC Docket No. 50-455 Reference (a): May 21, 1986 letter from K. A. Ainger to H. R. Denton
Dear Mr. Denton:
Reference (a) provided a report on the final disposition of ultrasonic indications identified in the Byron Unit 2 steam generators and pressurizer during the Preservice Inspection. Commonwealth Edison concluded that the indications were either small slag inclusions formed during vessel
' fabrication or weld inner diameter surface geometry. The indications were not cracks or lack of fusion. The location of the indications makes their removal very difficult and their removal would not guarantee an increase in vessel integrity. Consequently, Commonwealth Edison proposed not to remove the indications. This is based on fracture mechanics analyses that indicate that the indications, if assumed to be weld flaws, will not grow to.an unacceptable size during plant life.
The NRC has reviewed the report and concluded that commonwealth Edison's disposition of the indications provides an acceptable level of quality and safety if the following inservice examinations and tests will be performed:
a) The area containing the flaw in the pressurizer must be reexamined in accordance with the inspection interval o
requirements of IWB-2420 and the areas containing the flaws in the steam generators must be reexamined during the first two inspection periods listed in the schedules of the inspection programs of IWC-2411 or IWC-2412.
b) The pressurizer and steam generator secondary side hydrotest and leak tests must be performed at temperatures greater than those listed in the attached table.
f0 8611040358 861029 PDR ADOCK 00000455 G
PDR'
... ~.
Mr. H. R. Denton October 29, 1986 commonwealth Edison will perform the above inservice examination and tests on the Byron Unit 2 steam generators and pressurizer.
Please direct-any questions regarding this matter to this office.
one signed original and fifteen copies of this letter and attachment are provided for NRC review.
Very truly yours, K. A.~Ainger Nuclear Licensing Administrator la 1
Attachment cc: Byron Resident Inspector I
i l
l 2324K
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ATTAC19EENT MINIMUM HYDROTEST AND LEAK TEST TEMPERATURES FOR THE PRESSURIZER AND THE SECONDARY SIDE OF THE STEAM GENERATORS MINIMUM MINIMIUM HYDROTEST LEAKTEST COMPONENT TEMPERATURE (*F)
TEMPERATURE (*F)
Secondary Side of Loop 1 Steam 165 140 Generator Secondary Side of Loop 2 Steam 120 120 Generator Secondary Side of Loop 3 Steam 165 140 Generator Secondary Side of Loop 4 Steam 150 130 Generator Pressurizer 120 120 i
2324K 4
mm
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