ML19263C506
| ML19263C506 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 02/16/1979 |
| From: | Lundvall A BALTIMORE GAS & ELECTRIC CO. |
| To: | Reid R Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7902260364 | |
| Download: ML19263C506 (6) | |
Text
.
BALTI M O R E G AS AN D E LECTRIC CO M PANY GAS AN D ELECTRIC BUILDING B ALTl M O R E, M A RYLA N D 212 03 ARTHUR E. LUNOVALL, lR.
v.cc e t..oc,
Su pet e Of fice of uclear Eenetor nerulation U. C. I'uclear Fe ulatory Cc-incion
'<7achinrton, D.
P.
M555
/s ttn : ' 'r. Robert '.'. Peid, Chief Onoratire Danctern
"""nch "h
Divinior of Onerntirn Ponctorn "ubject:
Univort Fli""a "ne'e'tr Power "lant "nitn "on. 1 % P. 'leket ':on. 50 '17 6 "0 '11
"~n!'
treak "Pr" ?nn!, sir n foienca-
l'" lotter a nto ! ^/l^/70 Prcr "r.
Is. P
" u" l': 'll l,
r to '9. R. " n ei',
c r e c ub.' o c '-
Centleman:
m:e rn'orenced lo* tor donari?a! nome rocent devolonr.ont-cor. carn!nc the
-n17-breny Tr.n-of-coolant-nectio,4
' 7 ^ o A )
r" a" rnalyni:
or en!vart c
El f ""n.
Tr t' 't t ' otter ~ n'nt'd that o voul? n fm "7F o f th' "e ui t r o e annl /ni: heine nor"or-h" P^~buntion "r-Ineerinc to rraliet whetha" rmn'l bre @ n *culd rr~ni 1enn
'+1r~ thnn 2 n-o 'c ro'th n ovan if Pe :ce of t etnrcir 4 r'r"r dalete' "ro~ t'te cmn11 Frcnk ann'vnir necr atin^n-
'. 70 ren i the renultn of the above 1ralvain er.le ineniny, February Th anl m.;niucted a tolonhone onference that afternoon involvin-
?o-1 ntion "ncinoorinc
{}, cembern of our "lectrIc Production, Plectric Pncineerinr n".4 nunlit: Accurance Dennrtmontn, and our Plant ornr,tjerg nna On#oty Fov iev Cc-itten ( P0"D) nnd O f f-F i ta a f e tx -na Dev i ev
n~~ i
- t ne (PP"'P'
~ 2 pu" race o" that onferenne van to discunn th method "nd recult~ of the nun!" sic and to mnke a decinien on returninc to the ntretch nover oneratinc linits ( P700 'f.7t ).
After "attifa' tor" connlotion of the revinu nnd with the
- c. nwr-nee of the POlRC ann C""PC, the docinion "an ~ade to retu"n to the hirher power linit ( ?700 ' n!t ).
'"hir decinion and a r umnary of the renults of the analynic were ecmunie'ttel to your .taf" by toledono Inter that on~.e afternoon.
We are encionine a ecpv of the abovo nentinned analynin-
/n stated in our February 12, 1970 letter, C" 2: nroceeding with a full contuter analynin of tho vornt enre en't11 Fre@ LO"A, nnouninr r.o chargire rumpn.
We exnect the results of that analysin ir about three weekn.
In the
&r\\ 9 \\
790226036L
\\
-?-
interim, we have determined that the encloced analysis providen adequate assur.mee that the cmall break LOCA, assuninc no charging rumps, rer.ains lera limitinc than the larre break LOCA at 275h "'Jt (10?" of 2700 '"Jt) and that, therefore, +he 2nrce break ECCG analysen previously cubnitted in our reload and stretch power nutmittals and annroved ty the !IRC satisfy the ECCS Acceptance Criteria (10 FFR 50.h6 and Annendix K), nr.d provide the basic for continued operation at 2700 "'Jt for both Calvert Cliffn Units.
If you have any ouestions concerning the enclosed analysin, please contact un and we vill be pleased to discunn it with you.
Very truly yours,
/
Yh ec - J. A. Biddison, Ecquire O. P.
Trowbridge, Enquire
?fensrs. E. L. Conner, Jr., ::FC P. W.
Fruce, CE
CALVERT CLIFF 3 U'iTT9 1 & 2 CitALL BPFAK FCCS PERF09"A"CE AT P75h 'Nt WIT!!OUT CIIAPGiI , FII'm FLOW
1.0 Tntroduction and nunmarv.-
The rnall break LOCA ECCP performance for Cn1 vert Cliffs Unita 1 and P presented herein demonstrnten apnropriate confornance with 10 CFR 50.h6 which presents the Acceptance Criteria for Enerrency Core Cooling Systenn for Light Water Cooled Peactora (I I. The evaluation denenstraten acceptable ECCS nerformance for Calvert C]if fn Units I and P at a peak linear heat generation rate of 16.0 kv/ft and reactor nover level of 275h ! Sit (1.025 of 2700 ISit) assuming no credit for injection fron the charging pumps. The method of analycin and resulta are presented in the following cection.
2.0
'iethod of Analysis and Renults Feference 2 nresents the Calvert Clif fn anall break LOCA ECC3 performance at a reactor power level of '611 'Mt (1.n?I of P560 "ilt) and a reak linear heat reneration rate of 15.8 kv/ft.
In the reference ^ analycic,
a the 0.1 ft'~ cold ler break in the runn dincharge was identified as the vorst naall break with a calculated peak clad te-nerature of 1855 P and a neak local clal oxidation nercentage of h.305.
The e'caluation presented herein nertains to a conrervative ancecoment of the performance a
for the liniting 0.1 ft' bren'., of Fo ference ?, nt a reaetor nover leve er 275h ! Sit and peak linear acat reneration rate of 36.0 kv/ft. Sic conservative acnescrent van perforned an a three-step nrocess-
- rirnt, o
the two phace level in the core for the 0.2 ft' break of pererence 2 van anservatively reduced to reflect the increated boiloff expected fren the higher power level. Flith thic decreared level, the additional time the hot cpot remains uncovered var calculated This tire van then used to determine the increane in reak clad te:rnerature an a result of the hicher power level and lover core two phane level. Purthernare, baced on thic conservative evaluation of the ECr" performance for the
O 0.1 f t' break at this higher power level, it han toen determined that the increase in neak clad tennerature in less caan I?O F vhile the increace in peak local clad oxidation nercentare has been deternined to be lenn than 6.0".
It c<.n, therefore, be cor.clu3e:1 that the neak clad tennerature and 2
peak local clad oxidntion for the limitinc 0.1 ft hreak at the hicher core nover level in less than 1975 F and 11.05, resnectively.
3.0 Conclucion An ancestment of the ECCC performanen for the vorct reall break LC"A for Calvert Cliffs at a reactor nover level of P75h "Wt and a peak linear heat ceneration rate of 16.0 kv/ft hac been nerformed. The anneccrent concervatively determined the neak clad terrerat':re to be lens than 1075 F and the reak local clad oxidation percentare to ha lens than 11.05 vithout credit for injection from chargine numps, thereby, d mo.intratinc apnreciable narrin relative to the Secentance Criteria for ohe verst cnall break LOCA. These raculta also demonntrate that the limiting break for Units } and 9 remains the 0.8 doable ended slot break in the cold leg at the mimn discharre, reported in Peference 3, in which the neak clad temnerature vac calculated to be 21P3 F vith the neak local clad oxidation rarcentaca of 15 535 at the neak linear heat reneration rate of 15 5 kv/ft.
h.0 Referencen 1.
Accentance Criteria for Emergency Core Cooling "yctens for Light-Water Cooled "uclear Power Peactors, Federal Recicter, Vol. 39, "o.
3 - Friday, January h, 197h.
2.
C'.iPD-137, Sunplement 1, " Calculative "ethods for the CF Cmall Preak Evaluation "odel", January 1977 (Proprietary).
3.
Letter from BG'm to the imC trancmitting the Calvert Clirre Unit 2, Cycle 2 ECCS Analysis, I'ly 31, 1970>-