ML20076B899
| ML20076B899 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood, 05000000 |
| Issue date: | 08/15/1983 |
| From: | Swartz E COMMONWEALTH EDISON CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| 7138N, NUDOCS 8308220074 | |
| Download: ML20076B899 (2) | |
Text
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ON. Commonwealth Edison s
V{ )7 Address Reply to: Post Office Box 767
~* -
One First National Plaza. Chicago, lihnois j Chicago. Illinois 60690 l
August 15, 1983 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
Byron Station Units 1 and 2 1983 ASME Code, Winter 1983 Addenda NRC Docket Nos. 50-454/455 and 50-456/457
Dear Mr. Denton:
The purpose of this letter is to obtain permission to use the Winter 1983 Addenda of the ASME Boiler and Pressure Vessel Code at Byron Station; specifically,Section V, Article 2, paragraph T-263.3.
The Winter 1983 Addenda has been completely approved by the Committee; however, it is not scheduled for publication until the end of the year.
A problem arose at Byron Station when it was noticed that penetrameters were not shimmed when radiographing reinforced welds.
A Code Case was written (1948) to approve of this procedure, but it is still in Committee.
Meanwhile, the next Addenda (W 83) was revised to allow radiography without shims.
Specifically, the following paragraphs were changed from:
T-263.3 Shims Under Penetrameters (a) A shim of material radiographically similar to the weld metal shall be placed under the penetrameter if the weld reinforcement and/or backing strip are not removed.
(b) The shim thickness shall be selected so that the total thickness being radiographed under the penetrameter is at least the same as the nominal single wall thickness plus the maximum reinformcement permitted by the referencing Code Section (if the reinformcement is not removed) plus backing strip (if not removed) and other thickness variations such as nozzle geometries, to:
T-263.3 Shims Under Penetrameters j hY 8308220074 830815 ffp PDR ADOCK 05000454 A
b
. (a) A shim of material radiographically similar to the weld metal shall be placed under the penetrameter if needed, so that the radiographic density through the area of interest is no more than -15% from (lighter then) the radiographic density through the penetrameter.
Byron Station is being built to the Summer 1975 Addenda, but, under NCA-1140(c), later Code Editions and Addenda may be used.
In our judgement, even though it is not issued, the Winter 1983 Addenda is approved and therefore should be available for use.
We have received concurrence with this position from Hartford Steam Boiler Insurance Company, (our Authorized Nuclear Inspection Agency).
By Reference (a), we have also notified the State of Illinois.
Because we are preparing to sign N-5 forms at Byron Station at this time, we request that you provide prompt review and verbal approval of this request, with written confirmation to follow.
To the best of my knowledge and belief the statements contained herein are true and correct.
In some respects these statements are not based on my personal knowledge but upon information furnished by other Commonwealth Edison employees.
Such information has been reviewed in accordance with Company practice and I believe it to be reliable.
If you have any questions on this please contact this office.
Very truly yours, g//5/83 E. D. Swartz Nuclear Licensing Administrator cc:
NRC Resident Inspector - Byron Station NRC Resident Inspector - Braidwood 7138N
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