ML19319B950

Safety Evaluation Supporting Revision of Tech Spec 4.5.2 Assuring Proper ECCS Flows During LOCA

ML19319B950
Person / Time
Site:	Davis Besse
Issue date:	01/13/1978
From:	TOLEDO EDISON CO.
To:
Shared Package
ML19319B948	List: ML19319B947 ML19319B949 ML19319B950
References
NUDOCS 8001290686
Download: ML19319B950 (1)

Text

.- .- _ . _ . . _ - - . - ~__ _ . _ - .

h i

1, DB-1 t

i SAFETY EVALUATION i

j i

l The proposed change for the Technical Specification Bases identifies the

! bases for this Technical Specification Change Request. The purpose of i the surveillance requirements 4.5.2 g. and 4.5.2. h. is to provide j assurance that proper ECCS flows will be =aintained in the tvent of a l

loss of coolant accident. Maintenance of proper flow resistance and pressure drop in piping system to each injection point is necessary to:

(1) prevent total pump flow from exceeding runout conditions when the system is in its minimum resistance configuration, (2) assure that the j design flow through the Decay Heat Removal Cooler is not exceeded and j (3) provide an acceptable level of total ECCS flow to all injection points equal to or above that assumed in the ECCS-LOCA analyses.

These proposed changes have been developed in response to Mr. John F.

Stol 's letter to Mr. Lowell E. Roe, dated November 9, 1977, concerning throttle valves in ECCS syste=s at the Davis-Besse Nuclear Power Station

, Unic No. 1.

i sf d/4 1

l i

s b

Sg c2 c) / g_%D

__ _. -- _ - _. -- .. - _ _.- - - - - _ .-