NRC-90-0078, Responds to NRC Bulletin 90-002, Loss of Thermal Margin Caused by Channel Bow. Util Has Decided That Fuel Channel Boxes Will Not Be Used After First Bundle Lifetime
| ML20042E707 | |
| Person / Time | |
|---|---|
| Site: | Fermi  |
| Issue date: | 04/25/1990 |
| From: | Sylvia B DETROIT EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| CON-NRC-90-0078, CON-NRC-90-78 IEB-90-002, IEB-90-2, NUDOCS 9005010153 | |
| Download: ML20042E707 (1) | |
Text
l}
(
a:
---?
N h
')..4
- D. Ralph Syld i Senor Vic3 Premdent
- 6d00 North Diese Hig$way.
EdlSOn_ Newport, M,chigan 48tti6 9
(313j fMr4150 -
April / 25, 1990.
NRC-90-0078 U. S. Nuclear Regulatory Commission Attn Document Control Desk-Washington, D.1C. 20555
References:
1)'
Fermi 2-T NRC Docket No. 50-341.
NRC License No. NPF-43 2)
NRC Bulletin 90-02, " Loss of Thermal Margin Caused by Chbnnel Box Bow"
Subject:
Detroit Edison Response to NRC Bulletin 90-02,
" Loss of Thermal Margin Caused By Channel Box Bow" Detroit Edis:on hAs reviewed NRC Bulletin 90-02 (Reference 2) which was received on March 26, 1990. This bulletin requested us-to determine _ whether any channel boxes are being re-used after -
their first bundle lifetime and, if so, to ensure that the effects of channel box bow on the critical power ratio (CPR) 4 calculation are properly ' taken into account.
In response to this bulletin, it is has been determined that fuel channel boxen will not be used af ter the first bundle lifetime.
Currently all channel boxes in the core are in their first bundle lifetime. Therefore, further review of the CPR with respect to technicci specification operating and safety. limits is not-l required.
L In addition, no CPR penalty associated with channel bow is being taken in Cycle 2 (the current cycle).- However, Cycle 3 will account for the effects of channel bowing using General Electric methodology which is expected to be approved before the next i
cycle.
If there are any questions, please contact John Tibai.at (313) l 586-4289.
l l
Sincerely..
[- -
l.
i cca A. B. Davis
- /j%
j g.
l R. W. DeFayette W. G. Rogers l
J. F. Stang
\\g 9005010153 900425 i
PDR ADOCK 05000341 I
O PDC-tj