ML17346A891
| ML17346A891 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 02/27/1985 |
| From: | Varga S Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML17346A889 | List: |
| References | |
| REF-GTECI-A-49, REF-GTECI-RV, TASK-A-49, TASK-OR NUDOCS 8503130313 | |
| Download: ML17346A891 (3) | |
Text
ENCLOSURE 2 TURKEY POINT UNITS 3 AND 4, SUPPLEMENTAL EVALUATION OF THE FLUX REDUCTION FACTOR USING PART-LENGTH BURNABLE ABSORBER ASSEMBLIES TO MEET THE NRC PRESSURIZED THERMAL SHOCK CRITERIA Introduction The staff has performed an evaluation of the flux reduction factor necessary for Turkey Point units 3 and 4 to be able to operate for 32 Effective Full Power Years (EFPY) without exceeding the NRC Pressurized Thermal Shock (PTS) screening criteria (Refs. I and 2).
That evaluation was based on a
.32% copper content of the peripheral weld which resulted in a maximum fast neutron fluence of 1.85x10
'2 n/cm for a RTPTS 300'F (Ref. 3).
The revised copper content is.26K (the Ni content is
.60%)
and the new value of the fast fluence is 3.97xlO n/cm.
As a result an additional 10'F is added to the RTPTS.
This alters the required flux reduction for Turkey Point 3 and 4 to operate for 32 EFPYs without exceeding the screening criteria.
Evaluation By 1nspection of Table 2 of Enclosure I (from Ref. 2) Unit 3 will accumulate 2.92xlO n/cm fast neutron fluence (E>l.OMeV) at the peak location of the 19 2
peripheral weld at 32 EFPYs assuming the present loading scheme.
Likewise Unit 4 will accumulate 3.09xl0 n/cm.
Both values are smaller than the
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19 2
revised value of 3.97xlO n/cm required to reach the screening criteria.
19 2
Conclusion Me have compared the revised value of the fast neutron fluence to the peripheral weld required to reach the PTS screening criterion.
Assuming that the present low leakage loading pattern will also be applied in the futur e, both units can operate for 32 EFPYs without reaching the PTS screening criterion.
Princi al Contributor:
L. Lois 8503130313 850227 ~
PDR ADOCK 05000250 P
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References tt r 23 1982.
1.
M. Dircks to omm ss C
issioners SECY-82-465, Novembe 2.
Initial Safety Evaluation, Enclosuree 1 to this letter.
'1 26
- 1984, (NRC) to J. Milliams {FPL) dated Apri l
M ter'als Dat fo T rke Point Evaluation of Reactor Vessel Materia s
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Plant Units 3 and 4 Reactor Vessels.
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