ML20076A972
| ML20076A972 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 08/05/1983 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, NUDOCS 8308180401 | |
| Download: ML20076A972 (2) | |
Text
-
l l
l TENNESSEE VALLEY AUTHORIT}IIU/@
~
CH ATTANOOGA TENNESSEE 37401 I[
400 Chestnut Street Tower II
,' WG //,
n adr Aug gg Alo: 43 August 5, 1983 BLRD-50-438/82-48 BLRD-50-439/82-43 U.S. Nuclear Regulatory Commission Region II Attn:
Mr. James P. O'Reilly, Regional Administrator 101 Marietta Street, NW Suite 2900 Atlanta, Georgia 30303
Dear Mr. O'Reilly:
BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 - DEFICIENT STEAM GENERATOR SUPPORT POLTS - BLRD-50-438/82-48, BLRD-50-439/82 FOURTH INTERIM REPORT The subject deficiency was initially reported to NRC-0IE Inspector R. V. Crlenjak on July 23, 1982 in accordance with 10 CFR 50.55(e) as NCR 1887. This was followed by our interim reports dated August 19 and December 21, 1982 and March 29, 1983 Enclosed is our fourth interim report. We expect to submit our next report on or about December 23, 1983 If you have any questions concerning this matter, please get in touch with R. H. Shell at FTS 858-2688.
Very truly yours,
-TENNESSEE VALLEY AUTHORITY L. M. Mills, anager Nuclear Licensing Enclosure oc (Fnclosure):
Mr. Richard C. DeYoung, Director Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.
20555 8308180401 830805 PDR ADOCK 05000438 S
'OFFICIAJ COPY ll An Equal Opportunity Employer
,.- ' ys ENCLOSURE I
BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 DEFICIENT STEAM GENERATOR SUPPORT BOLTS NCR 1887 BLRD-50-438/82-48, BLRD-50-439/82-43 10 CFR 50.55(e)
FOURTH INTERIM REPORT Description of Deficiency Several two-inch diameter bolts manufactured from SA 540 GR B24 material by Lakeside Bridge and Steel which are used in the upper steam generator restraints appear to be deficient. The deficiency involves loss of tension in the bolts after they were torqued to sixty-five percent of their.
ultimate strength. The bolts are in metal to metal joints. The loss of tension was discovered during reinspection of the bolts.
Interim Progress Sample bolts of those which loosened were sent to TVA's Singleton Laboratory for testing and evaluation. Results of the testing showed the bolts tested were not deficient. NCR 1887 was resubmitted to TVA's Division of Engineering Design (EN DES) for reevaluation and was returned with a recommended disposition to use a two-pass method of torquing. A single pass for torquing was previously used with 100 percent of required torque. The two-pass method will be adopted for all high-strength bolts requiring a preload of 50 percent of ultimate or larger. The two-pass method makes the first tightening pass at 70 percent of required value with the second tightening pass to be at 100 percent of required value. Further information regarding corrective action will be supplied in our next report.
l I
__-___-___-_-. _ -.