ML20107B332

Proposed Tech Specs,Changing Min RCS Flow Requirement to Take Credit for Use of Lump Burnable Poison Rods & Corresponding Decrease in Core Bypass Flow in Cycle 5 Reload Core Design

ML20107B332
Person / Time
Site:	Davis Besse
Issue date:	02/13/1985
From:	TOLEDO EDISON CO.
To:
Shared Package
ML20107B324	List: ML20107B329 ML20107B332
References
TAC-57219, NUDOCS 8502200349
Download: ML20107B332 (5)

Text

. - - . . - ._

i , .

Figure 2.2-1 Trio Setpoint for Flux -- AFlux/ Flow 8

Curve shows/ trip setpointGHfor-ep GEs sM4) flow reduction for three putmp operation (200,100 ppm). The actual setpoint will be directly i proportional to the actual flow with three pumps.

1 RATED THERMAL POWER i

UNACCEPTABLE 120 UNACCEPTABLE OPERATION OPERATION

(-18.2.106.8) (18.2.106.8)

"1=1.000 4 P MP - - 00 "2 -1.000 I

LIMIT

(-34.0,91.0)

' I 34.0,91.0) l l l l 80 i

• ^ (18.2,I79.7)

(-18.2J79.7) l iPUMP l

LyIT l*

(-34.0,6r3.9) - 34.0,63.9) l

- - 60 g i l ACCE ABLE OP! RATION R5t l SPEC IED RC P JMP COMByATION. l, I i _

_4o ,

1 I I l l l l 1 I I - - 20 l l 1 l 1 I .

l l l l e i t n l Ie It i 1 0 20 40 60 i ~60 -40 - 20 Axial Power Imbalance, 1 f

I 8502200349 850213

! PDR ADOCK 05000346 PDR

, P -

) .

paendment No. 11, 15. JJ. #1 DAVIS-5 ESSE, Ull!T 1 2-7 M , 80

- ~

' - ~- ......

r

,w- v - + , - - - , , + ,,,y,w-nr.,-e,- m y ,,_.,.,,,,-e,,

,_m , - , - ---,,n_-, , , _ - ,,.+,--pmy4.,,,,g. -,.m. - - - -- - --mw,a-v-, - - - - , - ,,- w------

(

k Figure 2.1-2 Reactor Core Safety Limit,

-  % RATED THERMAL POWER

- 120 (44,112)

(-48,112.0)g

-100 49,100)

(-49.100.0)h

(-48,'89.1) F (44,89.1)

F 3 PUMP LIMIT

-80 .g49,77,g)

(-49,77.1)t A?CEPTABLE

- 60

• OPERATION UNACCEPTABLE UNACCEPTABLE FOR SPECIFIED OPERATION OPERATION RC PUMP COMBINATION - - 40

~ ,

- 20 ,

I I f I a f .f I 60

-20 0 20 40

-50 40 Axial Power Imbalance, 1 REACTOR COOLANT FLOW, GPM PUMPS OPERATING 4 M+6 3 g h-y o y ,_--,,.--

)

DAVIS-CESSE, UNIT 1 2-3 Amendm:nt No. JJ JJ, JJ J5, 80

TABLE 3.2-1

,'  ! 018 MARGIN ,

G '

a LIMITS O

N Four Reactor Tieree Reactor Coolant Pumps Coolant Pumps

l, E Parameter Operating Operatine l 1 5

- Beactor Coolant ilot Les < 610

< 610(II

famperature Ty*F Reactor Coolant Pressure, psig.(2) .

III f 1 2062.7 1 2058.7 Acactor Coolant flow Rate, gpm I3I 3 088 1 96 1 8A,346 2 l l

l m '3% M4 7_91,oss o' 2

I m IIIApplicable to tiee loop with 2 iteactor Coo'laat Pimps operatlag.

I I2I Limit not applicable during either a Til[IlMAL POWER ramp increase la excess of 65 of 2i RATED lilfimAL POWER per minute or a lil[IlMAL POWER step lacrease of greater than 101

$ of RATED lit [RMAL POWER.

f 3

f. I3hese flows include a flow rate uncertainty of 2.51.

J I E

   .                                                                                  3
 ! U i

2.1 SAFETY t,!MITS BASIS l 2.1.1 and 2.1.2 REACTCR CCRE The restrictions of this safety limit prevent overheating of the fuel cladding and possible cladding perforation wnich would result in the release of fission products to the reactor coolant. Overnuting of the

                  -     fuel cladding is prevented by restricting fuel operation to within the nucleate boiling regime where the heat transfer coefficient is large and the cladding surface tamperature is slightly above the coolant sa::uration temperature.

Doeration above the upoer boundary of the nucleate boiling regime would result in excessive cladding temperatures because of the onset of departure from nucleate boiling (DNS) and the resultant sharp reduction in heat transfer coefficient. DN8 is not a directly ressurable parameter during operation and therefore THERMAL POWER and Reactor Coolant Tauer-ature and Pressure have been related to DN8 througn the S&W-2 DNS correlation.. .The DN8 correlation has been developed to predict the DN8 flux and the location of DNS for axially unifom and non-unifom neat flux distrinutions. The local DNS heat flux ratio. DNSR defined as the ratio of tne heat flux that would cause DNS at a particular core locat ion to tne local heat flux, is indicative of the margin to DNS. The mintaman value of tne DNBR during steady state operation, nemal operational transients, and anticipated transients is limited to 1.30. This value corresponds to a 95 percent probability at a 95 percent - confidence level that DNS will not occur and is enosen as an appropriate margin to DNS for all operating conditio ter/y The curve presented in Figure 2.1-1 seh@ resents the condi .ioW at which a minimum DN8R of 1.30 is predicted for t maximum possible thermal power GPM which is M 9t of l 1125 wnen the reactor coolant flow is ' design flow rate for four operating reactor coolant ouros. This curve is t based on the following hot chanr.e1 factors with pctantial fuel densifi-cation and fuel rod bowing effects: l Fh a 1.71; FN g = 1.50 Fq = 2.56; The design limit power peaking factors are the most restrictive calculated at full power for tne range from all control rods fully l- withdrawn to minimm allowable control rod withorawal, and fom the l

      $                   core DN8R design basis.

Y. 821 Amendment No. .d 3 3 DAV15-8E55E. tp IT 1

Pressure / Temperature Limits at Maximus Allowable Bases .Fiaura 2.1 Power for Minimum DNBR . IL 2400 - 3 PUur CURVE 2300 - x 4 PUNP CURVE 3

                                                .\       x
         =           2200      -

p, W 2l00 -  !

        . f-
      )::

R -

                                                ~~                                                                                *
           .          2000                                                                    .

u 3 1900 - . s 1800 - 1700 - e , , i _ . _, i , 510 620' 630 540 580 550 500 '

                                                            ' Reactor Outtst Temperature. (*F)                                      ,

FLOW (Gru) POWER _

                                -PUWPs
                                                    ... ..            1125 4               n ....

380,1 b o 89.6'o 5 2-a Arnendment rio..)f,)f,45 DAVIS-BESSE, UNIT 1 .}}