ML17053B974
| ML17053B974 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 09/09/1980 |
| From: | Tedesco R Office of Nuclear Reactor Regulation |
| To: | Rhode G NIAGARA MOHAWK POWER CORP. |
| References | |
| NUDOCS 8010010066 | |
| Download: ML17053B974 (8) | |
Text
a Docket No.:
50-410
.i.'j)g DISTRIBUTION:
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Niagara Mohawk Power CorporatiQn.-~ ~ '~-<<MRushbrook NSIC qQ 5
- Syracuse, New York 13202 RVollmer te
Dear Mr. Rhode:
DRoss
SUBJECT:
REQUEST FOR ADDITIgNAlXHQORMA'fIOQ.QEGQRDINQ 'PlEDYL4IPAG, TtHREADBAR, SYSTEM As a result of our review of your submitttal, dated June 17, 1980,. pegarding
- the, DYHIDAG Threadbar
- System, proposed.to be.used. inthe Nine f/ile Point Nuclear Station, Unit 2. we find a'eed for, additional, information.,
Our request for.this additional information is con'cained. in thy. enclosure to thjs llutter.
The enclosed questions, in draft forJii,.peeved as the meeting agenda for. the meeting held with your representatives,on, August., 14~,198p,)n
- Bethesda, Maryland.
This attached request gap additiona1.)nformationrefl,ects,in, the discussion.
he'td at, that meeting.
If you have any questions regarding, our request for.additional, information,. contact Kenneth L. Kiper, Prospect Managerat 301(482;,,7318.
Sincer ely, anginal signcEi by
@0bort L. '1'cdcscU Robert L. Tedesco, Assistant Director for Licensing Division of Licensing
Enclosure:
Nine Mile Point Nuclear Station,;
Unit 2, Request for Additional, Information
- 881oox.o ag,C, OFFICE
.SURNAME GATEf L:LBOl KKIper/ fsS ~.
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,NRC FORM 318 (9 76) NRCM 0240
~ 'U,S. GOVERNMENT'PRINTING OFFICE: 197 9.289-369
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ENCLOSURE NINE MILE POINT NUCLEAR STATION, UNIT 2 DOCKET NO. 50-410 DYWIDAG THREADBAR SYSTEM Provide the following information regarding the test data which you submitted by letter dated June 17, 1980.
a)
The total number of specimens tested for each bar si'ze.
Bis'cuss whether there were rejections of any test results,and indicate the reasons for the rejections.
b)
The test data submitted applies to. the splices which use hex nuts.
Discuss the other two types of splices.
c)
Fromthe test data submitted, we observed that the ultimate strength of'he spliced specimen'is generally less than the unspliced specimen.
Discuss the reason for this behavior,'the splice-bar interaction
- effects, and the. implications and interpretations of such behavior...
d)
We also noticed that spliced specimens demonstrate a softening
. effect at the yield level when compared to unspliced specimens.
Discuss the reasons, interpretation, and implications of such behavior.
e')
Provide a description and interpretation of the failure mode 'of each specimen.
f)
Provide a statistical description of the test data, such as confidence levels for ultimate strength and the amount of data scatter.
We hive found that. information regarding the following parameters and their variability is required in evaluating the performance of the DywiDag system.
Discuss the following items and supporting test data:
a)
The effect on performance due to dimensional tolerances in the splice couplers; rebars, and nuts, including those in threading.
b)
The effect on performance due to tolerances in the physical properties and the chemical composition of the material rebars,
- couplers, and nuts.
c)
The effect on performance due to variations in field conditions during installation, such as the alignment of rebars to be spliced, temperature and humidity, d)
The effect on performance due to, low (or high) service temperature on materials of rebars, couplers and nuts.
For the purpose of evaluation and testing, the low temperature may be taken to be-20'F and the high temper ature, 150'F.
I~
e)
The effect on performance due to a split in the rebar.
3.
According to information given with your, letter, dated June 17, 1980, the DywiDag System has been used in the construction of nuclear power plants in several foreign countries.
We require the following information in order to evaluate the actual performance record of the system.
a)
Provide, details as to the actual locations at which splice bars are "used in She"above cited plants; the types of loads and stress levels these bars are subjected to and their erection specifications; any observed failure of these splices and their causes.
Also indicate any deterioration due to corrosion or environmental
- effects, such as temperature and moisture.
b)
Provide construction and installation records, such as amounts of
- discards, continuing performance test results and.staggered or unstaggered splices.
Also, provide the QA/QC procedures observed during erection.
c) d)
The DywiDag system'is presently used in Germany on Class I nuclear structures.
Discuss how this system
> meets the German standard or criteria for splicing.
How does the German standard compare to the American standard?
Discuss the technical merits and advantages for using thi s sytem versus other approved methods.
4.
Discuss the planned uses of the DywiDag system. on Nine Mile Point, Unit 2.
Indicate,:the expected stress levels, the types of loads, and the configuration (staggered or unstaggered).
Compare these uses with previous uses in foreigh plants.
5; Tests were performed by Ontario Hydro comparing the DywiDag 'system with, three other splice systems.
If available, provide the results of these tests';
6.
The staff is aware of the use of.this system by two U. S. nuclear plants, ANO-1 and Millstone, neither of which involved safety structures.
Are you aware of the specific applications.
If so, provide a description of its use arid any available performance history on these plants.
7.
In conjunction with code case N-186, provide QA/QC related information, such as training of splicers, quali'fication of splicers,
.and inspection of the rebar,
- coupler, and the finished splice.
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'Nagara Mohawk Power Corporation
, ccs:
Eugene B. Thomas, Esq.
- LeBoeuf, Lamb, Leiby 5 MacRae 1333 New Hampshire Avenue, N.M.
Suite'100 Hashington, D.
C.
20036 Anthony Z. Roisman, Esq.
Natural Resources Defense Council 917 15th Street, N. H.
)lashington, D.
C.
20005 Mr. Richard Goldsmith Syracuse University College of Law E. l. White Hall Campus
- Syracuse, New York 13210 T,
K. DeBoer', Director Technol ogi cal Devel opment Programs New York State Energy Office Swan Street Building Core 1 - 2nd Floor Emoire State Plaza
- Albany, New York 12223 Resident Inspector Nine Mile Point Nuclear Power Station P. 0.
Box 126
- Lycoming, New York 13093
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