ML20154E689
| ML20154E689 | |
| Person / Time | |
|---|---|
| Issue date: | 05/06/1988 |
| From: | Berlinger C Office of Nuclear Reactor Regulation |
| To: | Wong A STONE & WEBSTER ENGINEERING CORP. |
| References | |
| REF-PT21-88 NUDOCS 8805200292 | |
| Download: ML20154E689 (3) | |
Text
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MAY 0 1988 p
Mr. Albert Y. C. Wong Stone & Webster Engineering Corp.
245 Sumer Street Boston, Massachusetts 02107 Gentlemen:
The Nuclear Regulatory Commission (NRC) was infonned by Hilti, Inc., in accor-dance with 10 CFR Part 21, of recent tests of Hilti Kwik-Bolts that indicate that the previously recorrended minimum edge distance from an anchor bolt to an unsupported concrete edge may be insufficient to develop 100% of the recom-mended anchor capacity. The Hilti test results indicate that Hilti Kwik-Bolts placed at a distance of five anchor bolt diameters from an unsupported edge, as recommended by the Expansion Anchor Manufacturers Institute (EAMI) guidelines, have only 30% of the recommended anchor shear capacity and 787 of the recom-mended tensile capacity. Hilti further indicated, at a reeting with the NRC staff, that the test results are believed to be applicable to other expansion anchor bolts that use the same type of anchor rechanism as Hilti Kwik-Polts.
The NRC staff feels that the test results indicating a 70% reduction in shear capacity are significant and indicate that there is a potential safety concern that will require further NRC review.
In view of the foregoing, the NRC would like to invite representatives of companies that supply bolts or provide bolt installation services to the nuclear industry, such as your company, to attend a meeting where pertinent infonaation could be frealy exchanged between meeting participants. The meeting is scheduled for May 24, 1988, at 1:00 p.m. in Conference Room 12-P-11 at the NRC's White Flint Building which is located at 11555 Rockville Pike in Rockville, MD. We are requestino that attencees present a brief presentation, approximately 15 minutes, that addresses the subjects listed in the meeting agenda and any other aspects related to this issue which you consider irportant.
If you plan to attend, or if you have any questions or concerns (such as how to present proprietary information), please contact Jaime Guillen at (301) 492-1153 or Rom Lipinski at (301) 492-0844 before May 16, 1988 Your cooperation on this matter would be greatly appreciated.
Sincerely, Original Signed Bf Carl H. Bulinger Carl H. Berlinger, Chief
@%!$2 MSbi Generic Cocrunications Branch es Pnn Division of Operational Events Assessnent Office of Nuclear Reactor Reculation
Enclosures:
1.
Feeting Agenda 2.
Subjects of Presentations DISTRIBUTION w/ enclosures tERossi,hRR CHBerlinger, NRR JGuillen, NRR h'
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MAY 6 1988 i
May 24, 19PS Meeting Acenda t
item Speaker Time I.
Introduction NRC 1:00 - 1:15 p.m.
i II. Presentations by A/Es 1:15 - 3:45 p.m.
Architects / Engineers
- III. Discussion / Forum Attendees 3:00 4:45 p.m.
i i
- Invited Architects / Engineers'
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Bechtel Power Corporation Brown & Root, Inc.
i H. J. Degenkolb Ebasco Services, Inc.
4 Gibbs & Hill, Inc.
Gilbert / Commonwealth, Inc.
I Sargent & Lundy Engineers
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1 Stone & Webster Engineering Corp.
Tennessee Valley Authority URS/Jehn Blume Associates a
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- - = -
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MAY 6 1988 r
4 Principal Subjects of Presentations I.
What was the "edge distance" as defined in the job specification in nuclear power facilities that you have designed and/or constructed?
II. Identify the type of anchors to which the "five diameter" or other edge distance criteria applies (expansion anchors, cast-in-place anchors, or all).
III. Discuss briefly the type of anchorage used for different types of safety-related equipment in nuclear power plants.
IV. Describe the anchorage design methods used for nuclear power facilities.
V.
Describe any anchor tests conducted by your organization and indicate whether any reinforcement, either parallel or normal to the free edge, was present in the test sam,les.,
VI. Based on your experience, estimate the percentage of anchors installed in nuclear power facilities designed and/or constructed by your company that could be affected by the "edge distance" issue.
VII. Present your perspective of the "edge distance" issue.
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