ML20202B164

Proposed Tech Specs Bases 3/4.7.1.5 Re Main Steam Line Isolation Valves

ML20202B164
Person / Time
Site:	Comanche Peak
Issue date:	02/05/1998
From:	TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:
Shared Package
ML20202B155	List: ML20202B150 ML20202B164
References
NUDOCS 9802110133
Download: ML20202B164 (3)

Text

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Attachment to TXX 98013 1

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MAIN STEAM LINE-ISOLATION' VALVES BASES l

TECHNICAL SPECIFICATI0i1 (3/4.7.1.5) 9802110133 990205 T'

PDR ADOCK 05000445 P_

PDR

Attachment to TXX 98023 Page 2 of 3 Page Number Descriotion B 3/4.7 7 This change revises the Technical Specificction (TS)

Bases discussion of surveillance 4.7.1.5 to delete the implication that the Main Steam Isolation Valves (HSIVs) should not be partial stroke tested at power. Also the f

implicit statement that full stroke testing is always performeo'in Mode 3. is revised to read " allowed" to be conducted in Mode 3. In addition, a sentence which indicated that an exemption to ASMF B&PV Code,Section XI is required to not perform full stroke testing at power is deleted.

Justification The current wording for.the Bases of Surveillance P.equirement 4.7.1.5 implies that partial stroke testing of the HSIVs should not be performed at power. CPSES MSIVs are designed for partial stroke testing and are required to be partial stroke tested gearterly by the IST Program. Also the IST procedure for full stroke testing is allowed in Modes below Mode 2 and does not require it to be performed in Mode 3.

The wording requiring revision was taken from the generic KdREG 1431 Bases and was included with the Bases accompanying a recantly approved TS change _ associated with extending the HSIV allowed outage times. License Amendment (LA) 54/40.

7 While LA 54/40 was still under review by the NRC, this section of the Bases was revised to eliminate most of the confusing words as part of the process _to convert the TS i > the improved TS. The revised wording was submitted to the NRC in the TS conversica submittal. License Aendment Request (LAR) 97 01. however LA 54/40 was not amended to reflect the revised wording at that time. This change updates the current TS.

The 1989 edition of ASME B&PV Code.Section XI permits quarterly partial stroke testing in lieu of quarterly full stroke testing (full stroke testing is only required during snutdown every 18 months) without requiring an exemption.

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I.-AttachmenttoTXX98023 l

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PLANT SYSTEMS hAsEs'-

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3/4.7.1.5 MAIN STEAM LINE ISOLATION VALVES 1

SR 4.7.1.5 (Continued)

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accident and containmeit analyses. This surveillance is normally i

Etaturning the unit to oper,ation fol; owfng 4refue1{no antag

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om a ssa with toe InservMsting Program pursuant e Fra uene a

to spec ficafion 4.0.5.

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l This test 1s conducted in MODE 3 with the unit at operating temperature and 3

nressure. Tlis SR is modified by a Note that provides exemption from 3pecification 4.0.4 for entry into MODE 3.

This allows a delay cf testing i

until MODE 3, to establish conditions consistent with those under which the acceptance'critacion was generated.

REFERENCES l

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10 CFR 100.11.

l 3/4.7.1.6 MAIN FEEDWATER ISOLATTON VALVES

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The feedwater isolation valves the feedwater isolation bypass valves, P

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and-the faredwater preheater byoass v,alves are designed to close on a Feedwater trip, and 2)gnal to 1) limit the cooldown following a safety injection / reactor Isolation Si limit the mass addition to the containment on a steaaline break result in over feeding of)a steam generator.y of feedwater sa1 functions which inside containment, and 3 limit the severit The allowed outage times and required actions are consistent with noneal plant operating requirements and the safety functions of the valves.

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L 3/4.7.1.7 STEAM CENERATOR ATMDSPHERIC RELIUM censures that reactor decay heat can be dissinated to the atmosphere in(ARYs)

The OPERABILITY of the steam generator atmospheric relief valves i

tta event

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j of a steam generator tube rupture and loss of offsite power and that the Reactor Coolant System can be cooled down for Residual Heat Removal System operation.

Two ARVs are required to cool the Reactor Coolant System in a time frame compatible with prevention of overfill of the faulted steam generator. All four 1

ARVs are required to be OPERABLE to allow for not being able to use the ARY on L[

the faulted steam gmrator and an active failure of one of the reeaining three ARVs.

2/4.7.2 STEAM rggTOR PRESSURE / TEMPERATURE LIMITATION The ' limitation on steam generator pressure and temperature ensur.as that the er >ssure-induced stresses in the steam generators do not exceed the maximum 6 lowable fracture toughness stress limits.

The Itaitations of 70*F and 200 psig are based on a steam generator RT, of 60*F and are sufficient to prevent brittle fracture.

Unit 1 - Amendment No.54 COMANCHE PEAX - UNITS 1 AND 2 B 3/4 7-3d i

Unit 2 - Amendment No.40 1

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