ML20031F381
| ML20031F381 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 10/01/1981 |
| From: | Owsley G SIEMENS POWER CORP. (FORMERLY SIEMENS NUCLEAR POWER |
| To: | John Miller Office of Nuclear Reactor Regulation |
| References | |
| GFO:090:81, GFO:90:81, NUDOCS 8110190686 | |
| Download: ML20031F381 (2) | |
Text
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ERON NUCLEAR COMPANY,Inc.
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P. O Box 1.5 RwMud Washngtars.9n52
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Phone: (509) 375-81001elex: 15-28?5
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0T A 0 ISOIk Mr. James R. Miller, Chief Standardization & Special Projects Branch 3q "'* M, p on Division of Licensi'ig Aj Office of Nuclear P.eactor Regulation N
U. S. Nuclear Regulatory Commission g'
4 Washington, D. C.
20555
Dear Mr. Miller:
In discussions with M. Tokar regarding his review of XN-NF-80-56(P),
" Generic Mechanical, Thermal Hydraulic and Neutronic Design for Exxon Nuclear TOPROD Reload Fuel Assemblies for Pressurized Water Reactors,"
Mr. Tokar asked for the results of the ECCS/LOCA and clad collapse analysis
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for the TOPROD fuel. Representative analyses have been performed for i
the TOPROD fuel scheduled for use in the Prairie Island units.
ECCS/LOCA Analysis An ECCS analysis was performed to assure conformance with 10 CFR 50.46 criteria for the Prairie Island Units 1 and 2 reactors operating with full or partial cores of the TOPROD fuel. The limiting break for the Prairie Island Units has been identified as the double-ended guillotine break of the reactor vessel inlet lir:e with a discharge coefficient of 0.4 (0.4 DECLG), and appropriate Fg and linear heat generation rate (LHGR) limits were established to assure conformance with 10 CFR 50.46 criteria for the standard ENC fuel designs. The TOPROD fuel design ECCS analysis shows that the Praire Island reactors can continue to operate at the same previously established limits of FQ and LHGR and remain in conformance with 10 CFR 50.46 criteria. At beginning-of-life fuel conditions, the results for all ENC fuel designs continue to support an allowable Fg of 2.21 and a maximum LH1R of 14.03 kw/ft.
The LOCA ECCS calculations used the ENC WREM-IIA PWR ECCS evaluation model. The limiting break (0.4 DECLG) was recalculated using the revised system input for beginning-of-life conditions.
Peak cladding temperature (PCT) was predicted to be 21480F for the TOPROD fuel. Results from the interim UPI model reduce this PCT by 130F to 21350F. The maximum local Zr/H O reaction was calculated to be less than 6%. The total Zr/H O 2
2 O
reaction was calculated to be less than 1%.
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,/o 9110190686 811001 PDR TOPRP EMVEXXN AN AFFlWATE OF EXXON CORPORATION C,
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Mr..l. R. Miller (USNRC) October 1, 1981 A second calculation, examining the sensitivity of the calculations to the clad strain and rupture model during reflood, was performed. The calculation reported above used ENC's approved clad strain and rupture model. The second calculation used the correlation reported in NUREG-0630.
The PCT for this latter calculation was 190F lower than for the calculations with the ENC approved model.
Clad Creep Cellapse Analysis The calculated clad instantaneous collapse pressure remained greater than the sys:em/ rod differential pressure and, therefore, creep collapse is not calculated to occur during the fuel rod design life. The clad ovality history is shown in Figure 5.3 of XN-NF-80-56(P). The maximum pin exposure used in this analysis was 45,720 MWD /MTU, corresponding to the maximum expected exposure for the Prairie Island irradiation.
i The maximum ovality at this burnup is 0.10 inch.
Please contact me if you have further questions regarding this matter, telephone 509-375-8241.
Sincerely, k
M G. F. Owsley, M,pnager Reload Fuel Licensing GF0:gf CC: Mr. M. Tokar (USNRC)
Mr. L. O. Mayer (NSP)
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