ML19254E910

Steam Generator Water Hammer Technical Evaluation

ML19254E910
Person / Time
Site:	Trojan File:Portland General Electric icon.png
Issue date:	09/10/1979
From:	EG&G, INC.
To:
Shared Package
ML19254E898	List: ML19254E897 ML19254E901 ML19254E907 ML19254E910
References
TAC-07390, TAC-7390, NUDOCS 7911050047
Download: ML19254E910 (15)

Text

.

STEAM GENERATCR WATER FA'I'ER IECHMIC#' E # A TROJAN POWER STATION Se:te.ber 1979 EG&G Idaho, Inc.

.1267 218 P00R BRGlWL

~

49 0

7911050 4

Cn.......61140.16)

,.1

?..

..$1%pebC l.k..

Ai ww t.

...................... s

-::.s^^a s eYc10M...

e t..

F---

1.-

J 7

F:-- L:s.0l.Jt

?-**

1 e

--.,e-.,

ee...n, J

w'f inX a iVit 4.

C ".t Lanw

...,N.-.0.

r d ! L. t..- L PLM ama;7 O

p - h.....

y,,-

-,g.

• m.'

y * ".., e =' V

't-

%LLw.0 4.4

• • i' 0 - L a. r i I C,,.......................

3 n

2.

EF ECTI'lENE55 DURING TRANSIENTS AND CONDITIONS u.n. v.e n 7

ra.aka,lre t ur. 10 e 'n i :K. av.................

a s

w.v a

7 7..1

,eactOr trip K

2.2 Less of Main Feedwater Ficw.

.....5 2.-;

, ass 07 Offsite Power.

8 w

9 2.4 Operator Error...................

2.5 Steam Line Break..................

9 2.5 Lass-of-Cool ant Accident.

10 IV.

CONCLUSIONS AND RECOMMENDATIONS..............

12

~::::e,eee.

......8,J

</.

M. -.

t w J P00R ORGINAL i a67 2i9

I.

INTRODUCTION (TPS) in evalut-i:n was perfermed fc-the Trojan F:uer 5: :i:n assess tr.e The :ur; se Of this evaluati:n was ::

1. e=:st e-systa.

e'fe :i.eness f :ne exis-ing means to reduce One actentisi for water

) during na-me-in :ne feedwa:ar systems (steam generater wa:er hammer Tne steam--ater slugging

-mal and hy:c:hetical coe-ating conditiens.

1. . a. a. ' r i.., s s.v e... s (' s - a.. i '. i a l 's y',. *. =. s '. = _=.. - a... a...'. -.

3 i r

.w..o. e. c.. +...,

A kncwn

1. eedwater pi;ing) aas considered in this review.

an: 1:j a er.:

steam generst:r wate-hancer has not occurred at the I?S.

2.. -

5. 2...=..

d. e '. v - 4. '. =.. i #.

.n a.

.r

.=2-

,a..a..=..r

=.=..

73.

u....e..,a>

Hence, this evaluation

1. sedwa e-system is maintained full cf water.

the means utili:ed at tne TPS ::

was casec en the effectiveness :#

maintain the feedwa er system full of water during normal and

,.....w.3.4...,.... e. 3.,.,.. '. n, c. n d. i '. i o n s.

The inf:rmation for this evaluati:n was Obtained from:. 5,

1) discussi ns with the licensee, 2) licensee submittals :f Augus:

21,1975, July 12,1975*, and October 22, 2

1975, October 1975~, 3) ne " Trojan Nuclear Plant Final Saf ety Analysis Re: ort"",

6

") " An Evaluatien 'of PWR Steam Generat r Water Hammer", NUREG-0291, 7

and.)

,estingncuse sechnical sulletin, NSD is 7 /.

n A descri::icn of the feedwater system at the TPS and its general The means to reduce One coe-ati:n is presented in Section II.

ctential f:r steam generat r water nr ner are presented in Sec-icn III, inclucing a discussion of their effectiveness caring

.2..-,

... s....,. a.

• w =.. s.r h a.....e r.

~ '... = 1. 1.v, w.,..lusions

...... s.

. ;- ~;-

z--

~.'*'....-:,.-.,.=.....,

.. -........=.

.p

, g e.

.a.m

• 8,

...g=

.ge

.g

.g a

mm. gme. d g

.4,3

......3.

e 4

m m.

300RORGNAL i757 2,n

• I.

r.'an.

• s 5y5 79 ta L

I.

n r..a, :....e,?....,.

w The feedsater system f:r the T?S was designe: :: ;r: vide an a s. a. n., s.....s..-,

e. f

e. s. a.s.w,. e o ~..u.e s,,., n.., r siu.a

e..s. a.: c.. s

a.,..

...i s

a s.

. s ceneraters during all Operaticnal c:nditiens.

Fee:sater is su: plied to

..,_,4...

e... s........_ 3 m. ". *. h. a. 2 *. e r " e.s '..n

... s >..d */

• n a.

s cendensate cum:s via the icw Oressure heaters.

Feer ater fec= the main feecwater Ouros is su clied :: a main header via :na nign :ressure hea*ars. The ain header s; lits in:C fcur 14-inCn feecdate* line: to su: ly a 10-inch #eedring ins' je each steam generat:r.

Feedaater is discharged downward through inverted "J" sha:ed tubes unif rmly distributed On top of each feedring.

e. i e w.....

i n e...,, a 4. n :..a..s.s a. 2., - _, s r..

u. c 3.s. :-.

.s 19,300 g;m a: 1530 fee: :::al deveic;ed head (TCH).

The :um:s are eacn criven by a 13,000 bnD variable s eed turbine. The turbine drivers are sucolied with steam, during normai two pumo coeratien, 'r:m the cutle*

Of the reneater m:isture separat:rs.

Steam fr:m tne main stea.m header is used during startuo and icw pcwer cceration.

The auxiliary feedwater system provides feedwater to the steam gene-aters # r residual heat removal during react:r startup and snutdown,1cw ocwer operation, and in the event of less of main feedwater ' low.

Auxiliary feedwater can be su:: lied by two redundant systems encicying a turbine driven auxiliary feedwater pumo in ene

,..,_, s.... e..

s.. <.,, -

...x14..,., : =.,.......... -.

.. =.

...3.,.

e

,.v. *.,

e.

3..

• 4.

2.3

..s..=.=..

...c.

3=.

........?.4 2..:

...s..-

a-

.a.

..s.e.-

.,,ga..ge e..,

..n.....:a.

.e

'.4

...,.11........:.

,o.g

=..,1...

.a.

s..1.,..

2....

1

.4

+-ae J.

1.

. 1 1

2-90lRORGINAl.

126.7 7c1 7

m

The ?.arbine driven and diesel driven auxiliary feecanter pum:s are

... e s..._... e q... -. 3.. :: :

e....

,,,. 3 c.. s.., s. e i j v o.,.

eca c.,

.w

... 3 r...

.s TCH.

The n0rmal water su: ly scur:e for tne auxilir.ry f eedwa:er sys em i s *. '. a.

. -. ' a. n e. =. *. a. s, r a. : a.

• =.. k w '. *. 5 a ". >.. k ". 3 s ". - s l.v =. ". = '. '..= o '. a. #. r...

...a.

se vice wate-system.

The diesel driven auxiiirry feed iter pump is su::llet witn ciesel

.. n. 3 1 i,,

(..g w.o o. r. e. c. c.,.

1. i n. '; d = -..= n k w '..*

J..-...=.d..

e.... ]

.v.i e

=-

w y

transfer Of fuel availab*e fr:m tne emergency diesei fuel Oil ransfer syste?. The turbine driven auxiliary feedsa:er pum; ::erates wita

.....<.n

...m a.1 e....,.. in s.....

.. d.,s.

in.

.. r... e.. 1 e

..s o....

• eCui-emen:s f 0r eaCn system are nCrmally suD: lied y inde:enCen Of#si'e 20wer sources via tne s*ar*uo transformers wi*h backup power pr:videc by separata diesel generatort.

CC power is use: to :: era e the s:eed governces for both pum:s and the thrct*ie valve in the turbine driven pumo steam su: ply line, 2.

C...e. v.L Cr.3...,M,.

..t i

Curing normal power operation of the reacter, the main feedwater system su: plies faedwater to the secondary side of the steam generators for hea: removal from the reactor cociant system.

The feedwater ficw is regulated by individual reculating valves in the main fee: water 3

..i1nes to eacn steam generator, one pos1:icns cr. the va..ves are aut:matically controlled based u:en steam generator level, stern ficw, and fee:wite" flCW.

222.

e.......

......,...e.,..

.:.,...... ~:., :. a.

.a

....1

.]

a....

.c.

..1...1 2...:. : :..,

2..s...

...2

..1.

a..-

2..

i.

i***.2T.*

3**

3

... # # 5.".*. *. "'"* *

• CT..**.

... i f*21-E*

..3

)

2..

J. e.....s...

.4 g.

g 2.,

2 2.*...

. m. a

.. :.a.

P00R ORIGI.N.A 1?67 22?

a::ut *T to ateut 20'.' cf full ::wer, feedwater is manually c:ntrolle:

a-: su:: lied.ia 1:w fl:s bypass lines wni:n by: ass the main feedwater regulating valve in each main f.edwater line. Ine bypass regulating valve in each by: ass lire all,ws c re a:: urate and resp:nsive feedsa er C :w C:nte:1 than.vould be,::ssible with One la* gar mai*. regul ating valves caring les :cwer ' nd 1:w feedaater fi:w) Operatice.

AbOve feedwater retuirer.ents of abcut 20% of full reacte

cwer, feedwater centrol is shif ted to the main regulating valves.

As p we" is increased, :ne sec:nd main feedsatar ;;m: is started and feedwater

1. 1 w is placed ur. der aut:matic centrol.

Autcmati initiaticn of auxiliary fee: water fics siii result upon ecei:t of one or m:re auxiliary feedwater :uma startuo signals.

The diesel driven and turbina driven pumps botn start on:

1) the c: incidence of twC CuL 0 three steam gene"ater icw-10w water levels

' :m any steam gene-ator, 2) the tripping of both main feedwater pumos, 3} a safety injecticn signal (SIS), Or 4) a turbine trip ::incicent aith the less of both offsite power sources.

Plant design s:ecifications alicw f or a maximum delay Of One minute from rece'pt of any auxiliary feecwater pump startuo signals to delive y of auxiliary feedwater to the stetm generators.

Administrative guidelines do not currently exist for limitation of auxiliary fee: water ficw during periccs of feedring uncovery.

At the

e-at:r's discretien, auxiliary feedwater is manually c:ntrolled subsecuent to actuation to maintain proper water levels in all steam generators.

1267 223 D{$ $$b

?. ? ?.

v. r.n.il t T.u a

A ti.t e. r t.g ;

fdt..fl.?w r r.

• • e

GR nes;R 6'.* v 8 7 0

,-m

... s 5..

sb

-eg : &: t 6. t...

w.....

T a..

+ 11..w.. r..,.... e.

.. - -,,.+1.v e..31.y..

.w, p.t

-...ca 4

e... =.... i a '

1. . a. r. s *. a. a,., a. n e.=.. r w a '. a. *..._=...e*..

.w,.

1..

a.s a e. g.., s.

. 4. 3. n...,.... w. 2 4.

5.., 3 3...

, '. s.. _.,

e

-o.,er....e

....,.4..,s

.. 11

.wo...7.

d i s w- '..a...=.. l a. s.i r a.

- l u -, a. d..

t n a d.. i. '.. r., *. *. a.

r a. s e n.

d. a. s i -

2 '. '...as #..r r-....-.

3 3

...a.i. d r.4.'.'..=*.i -.

• a x. 'i '. a. y #. a.a. d'a a. e r ' '.., -. - -.... a.

d Icss of main feed ater ficw and/:r steam geners :r fee: ring uncovery.

2.

A downward turning elb w On e=ch steam generat:r no::le

,1 4_ '... a *. a. s. " a.

a. i. #. a.. *. '. '. a. h.-. '... *..* *I l a.q -. 7 * #.

1. . a. a. d.w.=. a -

.i d.

D.-in

.2*

- h.a.

a.n *. *. 2. c a.

• o '. ".. a e. a..=.7.

3. m e.= *s.-. s.

-a.

3

. e The "J" shatad discharge tubes were ins *alled on ::: cf the

1. . a. a. d.. i., s *..- r *. < d. w' a.

1. . a r *.~*

.d i s.h.* r -a.

o #, aa'.a*

. =. 'ner *h*n '

• ...m.

discharge.

During eriods of feedring uncovery, this arrangement increases the time for complete drainege of tne feecrings and ass:ciated hcrizontal feedwater piping from less tnan ene minute to about 30 minutes.

Also, the maximum auxiliary feedwater f1:w (about 440 g:m ser steam generater) was not sufficient to maintain the

1. eedrings and feecwate-piping full of water wnen the feedrings had bott:m discharge holes.

The feedrings equi;:ed witn "J" shaped

.e........,.

w.e., w x.,=.,g e..

J...w.,..

J

.w....e.

, e.

.w.,.,

,w

.....g...

J...,....

g..

J...

...J..

fi.

. t 2

1 0. *.g o.,..

-T"

" ~...

4 2._....

...gne ; *...... 3..

s

.J J.,

3...... J a., g.

..3

.9.

.;_3 J.,

.4......

,.4..

g 3....

3....

....-.1.....:..

.s 2

.e.,

2.

., s.. g e.

.,.., 14 3..

.3.

2

.3

.s.

J.

J*.

.*..,.g.-*:..

ii.-1.*.

.a

. C

...,3..,

.,g..,

a.

_3...

24...

a.

3...

..^3..

3., s.. ;.....

4.J...

,4..

,4..

...... 2..

.. w.. a.r l a.v e. l

.s. - s " a. '. w '..=.

1. . a. a. s.. 4. n s i..n c r. a. er

..ra. s'.a 2m w.

3 7.w,.....:..='

1. .. r s >. a. r ". =.... =. - i s.= v.a '.. a. - i.' '. h a.

1. . a.a. d i. --. 3 2

-e.n..

.4

.2 ano feedwatar ;iping are kept full cf water.

7.3.,. -,... ~ -....-.<,

e.......-

...~...

w...,..x,.,..,.,..:=.s..,.=,

.a.

,. s s

e..-..., <. n :.. a +..,. :i.s

-.v:...s

,..a

,.s.,

=...:...

> =. 7..w..

....r...2 2 n.

s. a. a. d.w a '. c r. '. '. '.. 3#.. '. 'I c #.

w 2. '. =.. ' -.. '.1

1. . s. a.. r i n c.

.s e

.. s

= c. ". C V a.. V.

O.E C.= '. s a. '..h e " w'

• s h.= - a. d.

.d '. s C "..* *. - =. '. " ' a. s. o. '. '.' a *-a l a..= k.=

• e

..o.

t e... ~..u. a.

2 : a. e.

e.. n,

s. w.. a.

p..X i 1. i gp y s. a. a. s..g z =. c. e.

t. '. n. g

2.. n m.* 2 4. ~. u. s. e...k. a.

g i a. 3. '.

e ;

..i

.c s

a.

s s.d..gm

.....S.

,. -

• k s. *.'e. k ' m. a.

.s.e '../ c. n....*=9

4. e - a.- a.

'..b.,".

e.'.# #. *. *. '. s. r. *. '.a ' sc.-

N'. s si s -.

6. k. m.

s. o. dw.,. s e.

3.y $ a. s.m.. t o *i e at.... a r.

1 s

v.

n o..

Th.a.

J. a. c.. w.,. s. e. s j

4. q -

%= s...- - '3#. i a..' '.. '

.'..'.a

... a.

,"..-.#'"...='.

3.

au.

s i s i n e. s o... '. + n s.= '. *. ". e e n '.. =.n. =. 's o '.. a.

c *. a. =,. -=...a...='..-.s.

.A. w.w = r. d.

- 3 turning el5cw was attached tc the feedwater no::le of eacn steam generator wnicn effectively eliminates any heri:ontal piping at or at0ve the elevaticns cf the steam generat:r feedwater no::les.

This

=. -.> n. - am. a.. *. a. '. 4. '. n.2. = s *. ". a.

s a... '...n s a. #. -isin3

. M. a' = - a. n... s- '.".a.

s *. =. = m 3

c a. n.... r s '. "...> '. ". u l d.

• ..= '. n a.. d ". a. r.... a. 5..==.

1. .'.' '. e " -". - i., - =. - i w^ ^ e o #.

g.

feedring uncovery.

The ;otential for conditicns concucive to steam generator water hammer are therefore avoided in these piping sections.

Tests were Conducted on September 23, 1975 at the IPS to determine the effect of auxiliary feedwater ficw rates on the inducement of steam generat0r water h=mmer.

The eight tests simulated varicus normal and hycothetical 0;e-ating conditions.

Auxiliary feecwa er was atmi ted into a steam generatcr at ficw rates ranging from 120 gpm to 110 gpm.

..,.e steam generat r cressure was varied. rem *,v0 psig to.,, psig and 2.uu the feedring drain times (feedring full at time zero) were varied from s.

a -,., e..

......=

...e 1..-

^.:

.g-p*..,..*...:

aa.

..A

...f

....a..

a."

...11..

%N 1267 225

e 2.

f r.

• r.-

T. i.r r.,. ; q g n.A e

• u..e a n. y. u q.

,o.u, m. a v..,..e s.

~ ' '. '. " '.. '.

C n. n" C ". h~.

i O 'a r"s. -

4 n

.. -. a..r....=.

. =. - h.. : -..e. 'i c.$ 1. r.= q s i =. q. s = r. d.

e_a. r.. 3.. i r c..*.^..'.'.'.a.

e. 2 2.. -2..=.

... w 2.. _, n,.....e ar a.

'. i. s u s s a.e.

i n.. i. s s e.. i..-..

4...n. h a.

s.

o. x =... <... e f s.. w.. e. =.r.. i r. e.

7. c =.,. *. *. *. '. a. d. "C a.r.=.-e :.. r"

=..=.h.

e ".. s e.. 4.. n describes a transient resulting from a single initiating event or f ailure eith -he unit in normal ;cwer c;eraticn.

P:tential component

'.v, n.. n =.. 'i "..= i s. 2 2.. - c. n e r.=. - -

1-

.- - 2.y -. :... c.2...ra.s

>= 2.d'. a. r. r a.s " 4 '.

.= ri 2

e.

water hammer are accounted for in the analysis.

sing.e crite-ion was the : asis Tcr evaluating the erie: 1veness

.a

. e.

. w........e.

, a

.o s. t.. g. 1.v

.s.o..- o. - 3... e.. e.

4. 2

e..-. s. o n.. -

e. e.

.2 water htmmer.

The criterion is to maintain the feedwater system full Of water during the time frc7 the initia-ing event resulting in

e.. a. s. r 4.

..c-...y s u '. s =. ". u a. q. '.

1. . c. a. s. '..., r =.. v a.

.v.= n d.

s..= ". i 'i,.- a. d.

-a.=..

2.

er.e-at

wa e-inventory.

p..

Ka.,..-.-

A reacter trip with the plant in normal acwer cperation woui:

result in a turbine tric and cause the water levei in all steam generators to colla:se to a level belcw the feedrings. Within

., secones ci the resulting steam generator low,icw water,ieve,:

ou signals, the diesel driven and turbine driven auxiliary feedsater pumps would automatically start and sucaly auxiliary feedwater to the steam generat:rs.

If the initiating event for the reacter trip cid not clcse the main feedwater regulating valves, the valves would ciese u:en

~..

...=:...:.

~..= -...

.=...

. = = =-. :....=..

~

PQ@ Ofb 1267 226

.......$..,a.,. ~. u.e :. e-a... < nw r

n. u,.,....=...z..,5

c.,

y,..,.

b. z..... =.,.

..3

.. o

5.. s.w,...

4-,,

,. =. -.= r a. m e.'..-...

d, a, ' s v a..v '. w *. =...= s =. *. *.. =....= i n.=...

a". x '. '. i.=. v

1. . 4. =. '.w a *. =.. k e =. r. s '.".. a.

'. a.=. d.. d. e.. 3 s an. '. # =.a..w =. c.-

- '. r' 4...,

1. . a l i * #.

s

.a.=,

.s e:. v., i. =. =.,...x... r.: c w c..-

..a

..c

...,4.

=. s.w o. =. s '..,. ':.y

.~J. d.

'. a. i.. =.. ~ ~.. a. d.

" w a. **.'e i.)

'..*ss i

.. ~

Of cffsite ocwe, 2) malfunction or trip:ing of the main feedwater

.m:s,

.

ss or suc:1cn to the main reedwater pum:s, :r -) cicsure of A - =..>.-..- r. - i p h... >. <i n

1. . a. a_ d. w.=. a..-a...'i.2*'...,

=.."/-.

• s a l.= *. '. e n. va'v 4.

. e.

ra.s"i.i..3 s. * =.../ #. =. ~. '. w =.. =...'i.w.. d. s... a...n

. r =. e. =.1 s *.

'. o.a w....4.c-o..

signals and 1:w steam generator water level signals. The reactor trip

.. =..3'.=.

i =.". a.1. s i n.= 'i i s. = =.. g a.n =. =. -. s '.e c e s 't.=. s e

• .o a

~.

w..,. s.

. s.. e..

level beicw the feedrings.

The diesel driven and turbine driven auxiliary feedwater pum:s would start u en receipt of the subsequent

' :w-l aw stsim generator water level signals.

Auxi'.iary feedwater would s. =. = m. 3.n. e..= '..r s a.n d.

r =... v a. r. ". e.

1. . =. =.. '... 3 s.

r =. '. '. i l. ". a.

a

.- =. u s =.d se

.ne,icss ci main reeywater r,icw and the 11. eiy uncovery cr.

.(

tne feedrings would not result in substantial feecring anc fe' ' water piping crainage since the auxiliary feedwater pum:s ocuid start pecap-iy to su::iv feedwater :: the steam generators. Therefore, tne potential fcr wate-hammer is significantly reduced.

c.:

.:ss or u rsite ?caer

.ne c:m: te interrupticn c: cir stte ;cwer acuid resu.t in a i

ie react:r trio and autcmatic startuo or the emergency dieser generators.

.,a.:.. :.......:....a.... :. : x.... y.

....,..z.._

....e....

-.. =.........--:

... =

=.:.

P001 BWR 1267 227

As aas the case fcr tne icss of main feedsater 'lcw, auxiliary

=.,.s.,.,..=.

=...

. c.

.a

..., :.., :.....u.= :,,s.:.,g g r.

. a. s.s.,. =, ; :. :.. s,i a

.c a :. w s. *. s.,-.... 4 7...s e s. r.4*-

e

.= ":. ' n *... a - * *. =... i.2 7

1. .. r c

".a. *.

• v =.

• y' ^ C - '.' r s

.8.. d i i:

a a

..giw h e.

y py i...,.

.s a. a..

2.... a..

7.. *

" mars.-.

.. r.mr v.

~ u. a....:.~:..1,. :. r

,a s. : e.

.. :... :.. l n..e : :a.a p.. c. ~. a. e.

s y e =. =..~.. < e. e e.=..n e a s s

6

.o s.

.n

i..

if unccvered feedrings are allcwed to drain substantially af te-an e v a. q'.

".' ".s s.s

.".a.

s '. =. =.. c a.n a...= '. r w a *. = r '. a.v a. l s *.

• d r e..' e l.w '.". a.

s. a. a. s.. a... :... ige'.v'n "'.

'.=.=.'u.s.=..

i n. ~ '... a c..= '... e.- '. =. =. ~. '. n s.= n v"

.r =.

'. ' r i.- r.. 3 'i

1. . =. a. d. a.= *. = r.o '., d. a. : -. u I d.

• M. a. n -a. s ". l. i n v '.. = - l a : :-i.n =

2.. "

2 subsecuer.: water hamme.

The uncovery of One er botn feedrings is most

.l<eiy wnen ne p,iant is ccerating at icw power or curing startup since i

feedwate-is being regulated manually, rather than autcmatically.

For this situatien, an a.,ministrative limit c:.. 0 gpm on aux 1,4 iary 1:

feedwater #16w has been recc mended in Reference 6 based en tests

2.. -.... a. s.

2.

i n c '..= n.: a. i r.. ". n. i '..N o. 2.

u.. a. v a.

.". e '. = s. s s r. d ". c. =.. a *.

u One TPS (described in Section I!I.1) shew tha' no water h=mmer occurred under these conditions.

Therefcre such administrative ccntrols are not recessary fc-the T?S.

2.0.

steam Line :reak The :ctential for steam generator water hammer events resulting

1. cm ce ccncurrent with the rupture of a ' steam line inside containment

-ine sequence c:. events to,41cwing sucn a failure was was ccnsis.ered.

evaluated 20 determine if the break could result in tne 1) blewdcwn of

.a.

r.. v-. a.

.=.' " '. '. '. a. n.= ' s *. =.= m - =. n a.. a *. -. s.=. e' / a. r.? ) i n >." i '. i. v '. s. - '. v

.. 3.

.s

s.. _ - 3........-.......:. i.. J. J : e.. g.....

2..-

.:.g

.... :....~.~

g 4..

O.....

0..

. I !

~.. *....:..;. :...

0.-.....

..a 4

..a

.L.

• J

-*4

.g.s.....

.g.

• . J a.

• = =.

2. s..-.. 2

• J a

• • • ... J.

• =. =...e..

.m. a

..J 4 *r

,,J..

3.. T 3.,.

T.ac.

..f..:...

6-

..W q

C p% @$b D_67 2'8

stel ;enerat: wate-level signals.

telation valves in the auxiliary

1. eed4 ate-lines to the affectec ::ean generat:r woul cut Off auxiliary feedwater u cn recei:t of high fi w (500 g;m) signals sensed in -he l' es.

Auxiliary feedsater would continue to be su;;iled fur subse:uent refili :f tne unaffected steam genera: Ors and recovery Of ne fee: rings.

The bicwdown cf a steam generat:r w uld nct deprive the turbine driven auxiliary feedwater pum of driving s eam.

A check valve in eacn steam sus?ly line would prevent "crcssover" bicwdown thrcugn the sur:1y lines from the unaffected steam generators :: the ass:ciated bicwncown steam gener a:Or.

The Octantial f:r water hammer is icw after a steam line creak since nrc :t delivery of auxiliary feedwater in conjunction with tne "J" shaced discharge tubes maintain full feedrings and feetwater pi:ing

<, ~..b a.

. > ::....=..~.,s.

g ~. =. 1... - a. n a. r.,.,. g.

2.5 L:ss-of.Ccclant Accider.t The Dctential f0r feedwater water hammer during a postulated less-cf-coolant accident (LOCA) in either unit was examined because

1) a water hammer c:uld increase the consequences of a LOCA and 2) the

iant protective actions during a LOCA c:uld result in concitions wnich are concucive to water hammer if the feedwater system is not kept fuli

' sa:er.

A LOCA would result in an SIS, a reac:Or trip, a turbine trip, and subsecuen isolation of the feedwater system.

The startu: cf the

............:......,,,,z..,..,:...,.,.......

,..=.....

.q 4.4.

.=..,.......

=.

......... =.....,...

....:.::.:...=.... =.

P00R BRBM i267 229

......_,...,.e.....-......_,s,.,,.....3 2

...w

.4..,.......,_,,_,

...,,.-....,c.v=...,..c....-...-.

m.

e r a...**i_e 2

e.a. 3 F *. S T *

• j m..

~.=. c. a.g #. a. o... 6. 0 ~. 2 2 0 5 *. O r =..' '.' * * '* ". e t.

.s

..a w.

w.

..isc.,....,.,...n.........,...

.s..

1267 230 P00R DHNA

T ef.

,-..e,- e. %. i q - -.. q n. i u, ;. s.., ;. w.. g,, -

..s.t.

,;,,,3

-.ine =ssessment of the ca:abil:ty of exis-ing mea s :: ed;ce :he

ential f:r steam ;e. erat:r sa ar ham e carinc normal anc ny:::netical c: era-ing :nditiens was ciscussed in Secti:n III.

This assessment has sh:wn tha unde-c nditiens wni:n

.2. =.. - c..... c.. C o. <* =. w o, w

w=ter hammer in the feedwater systems (s:eCifically, unc ve ed and

Pa'ning eedrings and feedwater icing subjected to a:missi n of : Id auxiliary feecsa a-), :ne means available :: reduce :ne :::ential for w...- =. r a.

.,e ir5 are adequate :: maintain su "iciently full c.

w, c,.

~es *1ngs and feedwa ar ciping. Kee:ing ne fee:r

,.3 3ne fge w3 g7 i inc full of wa ar avoics the potentiei for water hammer.

Therefore, a.

n. -.. 3 u a.

...a

.. a..,. s. e-r a. s... - a.... =. -. =..n. a.., ". :.-

a a...,.

.. <.. _. 3... o. n.

=,-

-a water hammer at this facility are adequate and we rec mmend acceptance

" v. ~. n a..'m'~ e s.1::

1267 231 300RORGNAl.

=

- : :n- :.s s e. :3

./.

M....i v'. i..

41. ] : s..g, p.a r '. '4 a a. d C. 4. n o. ".2 'i 714. ".. * 'i w v v... - 2.*. v l. ? I. I P. '), l a. *. *. *. *

.w

... ] 2.,.

a' R a

.c.. % e... m. e... u-s ". 2.* s ". '. *. ". 2 '. - #.

• • • ..".*.i'.'.2.".

.m.

a.

.w w,

'Re:ce: of Steam C-enerator Feedwater Hammer Cesign C:nsicerations

.s.n. luc'aa..sr.3lsn r:..w. a.

e c

r.. r. e :i,

n'.,... s. :, i c. s :.

- r.

.-m s

s.

3

?.

.s'.

'; 4. i i i n..e., p e. e r.,

1.,.a,

y. a.

0.,.io.r.

e., c.i.. _

"T-ar.smittals cf re: ort entitled ' Report :n Test'ng Of Auxiliary Fee:4ater Addi.icn, Folicwing J-Tube Modificat';n to the Steam

=.. c.

3 -..

.e.

"...e Tro 4 2.n "s u c 1 = 2.

3'ia..'",

0-.

.=.

.?',

'. C. 7..

v

.r rte",

r....ut.,

,etter to n,.

.ecnwence",

..C, q.uDject -

2.

n.

v.

s in "Trar.smittal of reocrt entitled ' Report en Testia.g of J-Tube Modi #ication to tne Steam Generators with Reac Or Decay Heat at tr.e roj an Nuclear Plant '", July 12, 1975.

4 J. v. Cchner, Ovnamic Res:ense of the Trojan Feecwater Pice Due ::

Feedwate-Water Hammer for PGEC, Sechtel Pcwer Cor;cration, Transmitted := NRC on Oc:ccer 22, 1975.

rinai Sar. ty,nalysis n,ecort, d

rc. _.

iro;an.uclear Plant, e

N., c.

n Dockat No. 50-344

.c.

J.,. -.

sicc,, et al, n,n.tva,iuation or...,

team eenera cr..ater

. rax s a

Har=er, Creare, Inc. NUR5G-0291 (Decam:er 1975).

. ~ : =. a q a. *... ','.n '. s.

h..s... g r j n

.C

• m. s..g 0 =. a c. e..s

• a r.

~4. s. d.. s.. s. e.

i i a.c. e.

... i

.s c...z.,

.i..

?00R ORGINAL

.-