ML20154D817
| ML20154D817 | |
| Person / Time | |
|---|---|
| Issue date: | 05/06/1988 |
| From: | Berlinger C Office of Nuclear Reactor Regulation |
| To: | Ernst L MOLLY BOLT CO. |
| References | |
| REF-PT21-88 NUDOCS 8805190357 | |
| Download: ML20154D817 (3) | |
Text
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MAY 6 1988 (R g i
Mr. Larry Ernst, Product Manager Molly Bolt Co.
I 504 Mt. Laurel Avenue
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Temple, Pennsylvania 19560 l
1 Gentlemen i
i The Nuclear Regulatory Corrrnission (NRC) was informed by Hilti, Inc., in accor-dance with 10 CFR Part 21, of recent tests of Hilti Kwik-Bolts that indicate j
that the previously reconinended minimum edge distance from an anchor bolt to an 4
unsupported concrete edge may be insufficient to develop 100% of the recom-i i
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, i
have only 30t of the reconinended anchor shear capacity and 781 of the recom-mended tensile capacity.
Hilti further indicated, at a meeting 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 mechanism as Hilti Kwik-Bolts.
The NRC staff feels that the test results indicating a 70f reduction in shear capacity are significant and indicate that there is a potential safety concern I
that will require further NRC review.
In view of the foregoing, the NRC would j
like to invite representatives of companies that supply bolts or provide bolt installation services to the nuclear industry, such as your company, to attend 1
i a meeting where pertinent information could be freely exchanged between meeting participants. The meeting is scheduled for May 23, 1988, at 1:00 p.m. in Conference Room 12-B-11 at the NRC's White Flint Building which is located at l
11555 Reckville Pike in Rockville, MD. We are requesting that attendees
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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 important.
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If you plan to attend, or if you have any questions or concerns (such as how to J
present proprietary information), please contact Jaime Guillen at i
(301) 492-1153 or Rom Lipinski at (301) 492-0844 before May 16, 1988 Your
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cooperation on this natter would be greatly appreciated.
Sincerely, 1
Original Signed By l
Carl R Bnlinm 1
8805190307 Mne
- Carl H. Berlinger, Chief 4
PDR PT21 WR Generic Communications Branch se Division of Operational Events Assessment Office of Nuclear Reactor Regulation
Enclosures:
1.
Meeting Agenda j
2.
Subjects of Presentations DISTRIBUTION w/ enclosures CERossi, hRP, CHBerlinger, NRR JGuillen NRR EJButcher, NRR WDLanning, NRR RLipinski, NRR y$
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JGu D en RLipinski" CHBerlinger 05/L /88 05/L/88 05/01./88
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MAY 6 1989 May 23. 1988 Meetino Agenda item Speaker Tire 1.
Introduction NRC 1:00 - 1:15 p.m.
!!. Presentations by Manufacturers 1:15 - 3:00 p.m.
Manufacturers *
!!!. Discussion / Forum Attendees 3:00 - 4:00 p.m.
- Invited Manufacturers Hilti, Inc.
Molly Bolt Co.
Ramset/ITW/ Red Head Richmond Screw Anchor Co., Inc.
Tech. Services - Nuclear, Ramset Division - OLIN TRW Assemblies and Fasteners Group Nelson Stud Division
I' MAY 0 1988 1
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i Principal Subjects of Presentations l
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j I.
Describe your anchor products, their use, and the design reconenendations
.j provided to your customers.
i II. Does the "five diarreters" or other edge distance criterion apply to your anchor products? Provide justification for your answer.
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!!I. Describe any tests conducted by your organization that provides additional information regarding shear capacity reduction as a function of edge distance.
IV. Provide a list of known nuclear power facilities that use your anchor products.
V.
Describe your company's fatest reconenendations regarding edge distance j
control and their bases, j
1 VI. Approximately what percentage of your type of anchors are possibly affect-
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ed by the "edge distance" issue?
l VII. Present your perspective of the "edge distance" issue.
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