ML19250C430
| ML19250C430 | |
| Person / Time | |
|---|---|
| Site: | Perkins, Cherokee  |
| Issue date: | 11/08/1979 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Dail L DUKE POWER CO. |
| References | |
| NUDOCS 7911260110 | |
| Download: ML19250C430 (1) | |
Text
p....,'o,,
UNITED STATES
/ /~/
NUCLEAR REGULATORY COMMISSION
[ U, n
k 5
E FIEGION il c
o 101 MARIETTA ST., N.W.. SulTE 3100 o
ATLANTA, G EORGIA 30303 NOV 81979 In Reply Refer To:
RII:JPO 50-488, 50-489 50-490, 50-491 50-492, 50-493 Duke Power Company Attn: L C. Dail, Vice President Design Engineering Post Office Box 33189 Charlotte, North Carolina 28242 Gentlemen:
Enclosed is IE Bulletin No. 79-02, Revision No. 2 which requires action by you with regard to your power reactor facility (ies) with an operating license or a construction permit.
Should you have any questions regarding this Bulletin Revision or the actions required by you, please contact this office.
Sincerely, b0
'N
_ 'O f James P. O'Reilly Director
Enclosure:
IE Bulletin No. 79-02, f [,3 d
,1) l Revision No. 2 w/encls.
~~
7911260II O k
NOV 81979 a
Duke Power Company.
cc w/ encl:
J. T. Moore, Project Manager Post Office Box 422 Gaffney, South Carolina 29340 1594 222
UNITED STATES SSINS No.:
6820 NUCLEAR REGULATORY COMMISSION Accession No.:
OFFICE OF INSPECTION AND ENFORCEMENT 790822013e WASHINGTON, D.C.
20555
[f November 8, 1979 IE Bulletin No. 79-02 (Revision 2)
PIPE SUPPORT BASE PLATE DESIGNS USING CONCRETE EXPANSION ANCHOR BOLTS Description of Circumstances:
Inspection experiences ad the review of licensee response have identified several R2 areas where the Bullet;.. intent has not been adequately addressed by licensees.
R2 Revision No. 2 of the Bulletin is intended to clarify the intent of the Bulletin R2 and establish the NRC positions on minimum factors of safety, anchor bolt preload, R2 and the expected date of completion for certain Bulletin actions.
R2 Since the issuance of IE Bulletin No. 79-02 on March 8, 1979, IE inspection R1 experience and many inquiries from licensees indicate that additional informa-R1 tion and clarification is needed. This revision is intended to serve that R1 purpose. None of the requirements of the original Bulletin have been deleted, R1 and the due date for completion of the requested actions (July 6, 1979) has R1 not been changed.
The following text supersedes the text of Bulletin No. 79-02.
R1 Changes from the original text are identified by R1 and R2 in the margin.
The R1 purpose of this revision is to identify acceptable ways of satisfying the R1 Bulletin requirements.
While performing inservice inspections during a March-April 1978 refueling outage at Millstone Unit 1, structural failures of piping supports for safety equipment were observed by the licensee.
Subsequent licensee inspections of undamaged supports showed a large percentage of the concrete anchor bolts were no' tightened properly.
Deficiency reports, in accordance with 10 CFR 50.55(e), filed by Long Island Lighting Company on Shoreham Unit 1, indicate that design of base plates using rigid plate assumptions has resulted in underestimation of loads on some anchor bolts.
Initial investigation indicated that nearly fifty percent of the base plates could not be assumed to behave as rigid plates.
In addition, licensee inspection of anchor bolt installations at Shoreham has shown over fifty percent of the bolt installations to be deficient.
Vendor Inspection Audits by NRC at Architect Engineering firms have shown a wide range of design practices and installation procedures which have been employed for the use of concrete expansion anchors. The current trends in the industry are toward more rigorous controls bolts.
The data available on dynamic test DUPLICATE DOCUMENT fatigue failures can occur at load cities due to material imperfectio Entire document previously entered into system under:
R1 and R2 - Identifies those addit ANO 1
N o.
of pages:
.