ML20092E950

Revised,Proposed TS 4.4.4.1 Re safety-related Nitrogen Supply for PORVs

ML20092E950
Person / Time
Site:	Catawba
Issue date:	02/06/1992
From:	DUKE POWER CO.
To:
Shared Package
ML20092E913	List: ML20092E912 ML20092E950
References
NUDOCS 9202190021
Download: ML20092E950 (4)

Text

_. _ _ _ - _ - _ - _ _ _ ._

1 ATI'ACHMENT 1 REVISED PROPOSED CATAWBA MHNICAL SPECIFICATIONS CIIANGES

)

t i

A 9202190021 920206 PDR P

ADOCK 05000413 PDR

^

REACTOR COOLANT SYSTEM

$URVEILLANCE REQUIREMENTS 4.4.4.1 In addition to the requirements of specification 4.0.5, e(ch PORV shall be demonstrated OPERABLE at least once per 18 months by:

a. Performance of a CHANNEL CALIBRATION, and

b. Operating the valve through one complete cycle of full travel *.

l 4.4.4.2 Each block valve shall be demonstrated OPERA 6LE at least once per 92 days by operating the valve through one complete A ple_of full travel unless the block valve is closed with power removed in urder to meet the requirements of-ACTION b. or c. in $pecification 3.4.4.

mMy - nMd n'Mytn 4.4.4.3 The emar _ , ,__.-supply for-the PORV4 =d b b:E 1:h n shall be l demonstratedOPERABLEat-least-onceper-18monthsby:

a. Manually transferring-motive power from the normal (air) supply to

. the emergency (nitrogen) supply, -

b. Isolating and venting the normal (air) supply,-and

c. Operating the valves through a complete cycle of full travel.

m

In oeAer +o . ism vlsfu enhennun+n l- aHests rcyresen+ntin- 05' oycrefing conUfdu . SR f Y. 4.t . / b.' skov@ Lc- c ondvcicA w kco & Re u h r 'Coelant -

Syrtem ir m /c<n t vre, ir g rea k A n n .:t 00

• F) - Acuver, tNI tR- daI( nof rmek in tAnde % ' I . o r 3. ,

be Je AW8A - UNITS 1-& 2 3/4 4-11 Amendment No. (Unit 1):

Amendment No. (Unit 2).

0/10/00

REACTOR CCOLANT SYSTEM BASES SAFETY VALVES (Con'. -- J relief capability and will prevent overpressurization. In addition, tne '

Overpressure Protection System provides a divarse means of protection against overpressuriration at low temperatures.

During operation, all pressurizer Code safety valves must be OPERABLE to prevent the Reactor Coolant System from being pressurized aoove its Safety Limit of 2735 psig. The combined relief capacity of all of these valves is greater than the maximum surge rate resulting from a complete less of-load assuming no Reactor trip until the first Reactor Trip System Trio Setpoint is reached (i.e., no credit is taken for a direct Reactor trip on the loss of loac) and also assuming no operation of the power-operated relief valves or steam dump valves.

Demonstration of the safety valves' lift settings, will occur only curing shutdown and will be performed in accordance with the provisions of Section p.1 of tne RSME Boiler and Pressure Code. , ,

3/4.4.3 PRESSURIZER The limit on the maximum water volume in the pressurizer assures that the ,

carameter is maintained within the normel steady-state envelope of operation assumed in the SAR. The limit is consistent with the initial SAR assumptions.

The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> periodic surveillance is sufficient to ensure that the parameter is restored to within its limit fo. lowing expected transier't operation. The maximum water volume also ensures that a steam bubble is formed and thus the Reactor Coolant System is not a hydraulically solid system. The requirement that a minimum number of pressurizer heaters be OPERABLE enhances tne capaci!ity of the plant to control Reactor Coolant System pressure and establish natural circulation.

3/4.4.4 RELIEF VALVES The power-operated relief valves (PORVs) and steam bubble function to relieve Reactor Coolant System pressure during all design transients up to and including the design step load decrease with steam dump. 00:r: tier Of th:

10RV: minimi :: th: und::ir:bl: ;:ning Of th: :pr'7g-10:d:d peat:urizer Code

-te+ety v:!v::.- Each PORV has a remotely operated block valve to provice a positive shutoff capability should a relief valve become inoperable. rTesting'"N#f## ^

of the PORVs includes the emergency N supply from the Cold Leg Accumulators.

This test demonstrates that the valves in the supply line operate satisfactorily and that the nonsafety portion of the instrument air system is not necessary for proper PORV operation.

3/4.4.5 STEAM GENERATORS The' Surveillance Requirements for inspection' of the steam generator tubes ensure that the structural integrity of this portion of the Reactor Coolant Syste>n will be maintained. The program for inservice inspection of steam CATAWBA - UNITS 1 & 2 B 3/4 4-2

INSERT FOR TECliNICAL SPECIFICATIONS INSERT A (for Bases Section 3/4.4.4)

The OPliR A131LITY of the PORVs and block valves is determined on the basis of their being capable of performing the following functions: 1) Manual control of PORVs to control Reactor Coolant System pressure. This is a function that is used for the steam g,enerator tube rupture accident coincident with a loss of all offsite power and for plant shutdown. 2)

Maintaining thi. Integrity of the reactor coolant pressure boundary. This is a function that is related to contrelling identined leakage and ensuring the ability to detect unidentined reactor coolant pressure boundary leakage. 3) Manual control of the bek valve to unblock an isolated PORV to allow it to be used for manual control of Reactor Coolant System pressure and isolate a PORV with excessive seat leakage. 4) Automatic control of PORVs to control Reactor Coolant System pressure except for limited periods where the PORV has been isolated due to excessive seat leakage and except for limited periods where the PORV and/or block valve is closed because of te#ng and is fully capable of being returned to its normal alignment at any time, provided that this evolution is covered by an approved procedure.

This is a function that reduces challenges to the code safety valves for overpressurinition events. 5) Manual control of a block valve to isolate a stuck-open PORV.

1 1-e e,. e ,y.ec ....r... -,- p. p y-- ,ey -

e3 w , ,,-- r-w,,--.-- y3 w w .. y.-g w w,y g.,- --g, aywgw vsy--