ML19332F223
| ML19332F223 | |
| Person / Time | |
|---|---|
| Site: | Zion File:ZionSolutions icon.png |
| Issue date: | 10/30/1989 |
| From: | Rosalyn Jones Office of Nuclear Reactor Regulation |
| To: | Licciardo R Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19332F222 | List: |
| References | |
| NUDOCS 8912140079 | |
| Download: ML19332F223 (1) | |
Text
.
. =..
k Y
. Jf
- pofc d ' y, $_
]
I~
<f jo, UNITE D STATES
'g/
- j
+
8 NUCLE AR REGULATORY COMMISSION
,,.c e
.~I WASHINGTON, D. C. 20555 1-october 30, 1989 c
f5
.....o y cpp/L h tk E vu n
Robert B. A. Licciardo, Reactor Engineer (Nuclear) ( F/
MEMOF4 00M FOR:
r.
Plant Systems Branch M
Division of Systems Technology gg FROM:
Robert C. Jones, Acting Chief Reactor Systems Branch i
Division of Systems Technology g y
SUBJECT:
DIFFERINGPROFESSIONALVIEW(DPV)
^
Reference:
. Memorandum, Murley to Licciardo, dated September 13, 1989 On-September 13,1989'(Reference) Dr. Murley concluded that several
-actions should be taken in response to your Differing Professional View.
Enclosed is a copy of the guidance issued by me to the Reactor Systems Franch Engineers to ensure that pressure and temperature effects during a LOCA are considered in the review of new and advanced fuel designs.
i l
Robert C. Jo es. Acting Chief Reactor Systems Branch Office of Nuclear Reactor Regulation
Enclosure:
As stated l
cc:
T. Murley F. Miraglia L
i F. Gillespie J. Partlow
'A. Thadani H. Smiths /rg (YT #0899214)
D. Mossbu 8912140079 891211 fDR Aber.
ossos.]qs O.
Pbuyj
5
.h 45 u cg'o
. I(g r[g f
UNITED STATES NUCLE AR REGULATORY COMMISSION n
3
.I WA$mNGTON, D C. 20555
- 3) f october 25,.1989 MEMORANDUM FOR:
Reactor Systems Branch Engineers Division of. Systems Technology FROM:
Robert C. Jones, Acting Chief Reactor Systems Branch 1.
L Division of Systems Technology 1:
SUBJECT:
BRANCH REVIEW GUIDANCE:' REVIEW OF FUEL PIN 1.
PARAMETERS FOR LOCA ANALYSES L
Recently a Differing Professional View'(DPV) was raised concerning closure time requirements for containment isolation valves. Of concern was the possibility that cladding rupture, and therefore release of fission products, during a large break LOCA could occur prior to the containment being isolated.
As part of the'DPV resolution, a review of large break LOCA calculations was performed which demonstrated that cladding ruptures are not expected during the blowdown phase of'the accident for current fuel designs. Thus, containment l
l.
' isolation would occur prior to cladding rupture.
It'was also noted that studies of the timing of cladding rupture were generally only perfomed during the initial acceptance of the large break LOCA evaluetion L
models in 1974-1975.
However, numerous changes in fuel designs, such as L
extended burnup operation and its resultant increased internal fuel pin pressures, have been made. The effect of these changes on the calculated timing of cladding rupture has not always been addressed.
Since the review of the LOCA analyses performed as part of.the DPV resolution concluded that cladding ruptures were unlikely during blowdown for current fuel designs, no specific action is u cessary now.
However, as new fuel designs are developed, you should examine the fuel parameters to ensure that cladding 1
-ruptures will not occur during the blowdown phase of a LOCA. Should your review determine that such cladding ruptures are possible, you should alert the Plant Systems Branch so they can assure that containraent isolation is accomplished prior to the release of fission products from the fuel.
This guidance is immediately effec,tive.
s-Robert C.
ones Acting Chief Reactor Systems Branch Division of Systems Technology cc:
A. Thadant MMiou R * !! W !M4 -/A
- -, -. -. _