ML20057B339

Proposed Tech Specs Supporting Accelerated ABWR Schedule Re Containment Electrical Penetration Assemblies

ML20057B339
Person / Time
Site:	05200001
Issue date:	09/13/1993
From:	GENERAL ELECTRIC CO.
To:
Shared Package
ML20057B338	List: ML20057B337 ML20057B339
References
NUDOCS 9309210212
Download: ML20057B339 (2)

Text

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

21Asim nov. s of g yp*x(700*f)

ABWR , , mederd s="=g:iysis a: port _

' Tde EPAs K5tol 2n bfc ABWR Con nmenh wd.2 bC C*Pade o[7na4%,sh

.2eak Lcl z% ge conhum f-~%, bre.r.rurt. of t. o2 g rf& (;39

• R 5,,, ^.k G n *fj}emperature. Gret. Sub.seclan 8 3. s .7). __ j appears to be less likely based on the results of expenments conducted to chte by Sandia T National Labratories (SNL) and its contractors (Reference 19F-8). In fact, according to the same_ reference, no leakage was detected from any of the three current electrical _

penetration assemblie (EPAs) during the severe accident testing (steam bl9M9A RN environments). De din on the EPA type the highest temperature I g ran

@4b p< ^

from 6FFT70

~

, eDghest pressure loading ranged fronq5_ psia to 155 psia.

The leakage esumate in this study therefore concentrates on large operable penenations.

The leakage potential of operable penetrations depends on both the relative position l

of the serling surfaces and the perfonnance of the seal material. The position of the i sealing surfaces depends on the initial conditions (metal-to metal contact is maintained under design conditions for most penetrations) and on the deformations induced by t accident pressure and temperature. The seal perfonnance depends mainly on temperature as well as the effect of thermal and r=di= tion aging. The recent SNL tests of seals for mechanical penetrations, Reference 19F-8, indicated that

\.0 W o (1) In a steam environment at a con pressure o f 5 sia, the m f(,ob 1 >

degradation temperamre 20 forsilicon rubberand 30'F r ethylene proplylene rubber (EPR), and Ma 9 q' (2) In a nitrogen environment at a con t pressure o the mean degradation temperature wes(490'F f neoprene, and 59'y- '

(3) The degradation temperature was not signi5cantly affected by therry:0 and radiation aging. / '

Neoprene is not.used for operable penetrations in the ABWR c tamment and the seal 93'K

,A degradation temperature is conservatrvely assumed to be@'The SNL study also showed that even a degrad s can p xntleakage if the separation of the sealing i surfaces is small (less 0.005 in ). -

0 f Sandia (Reference 19F-8) has p\roposed the following equations for "available gasket springback", Sp, for evaluatmg the leakage potential as a function of the compression set retention and the degradation tcmperature: l l

Sp = (1 - C 3) Sq3h for (T < Td) (19F-3) i Sp = 0.005 inch for(T > Td) NS where: ,

C3 = the compression set retention (a dimensionless measure of the permanent set in the gasket caused by aging),

^ Containment Uttimate Strength - Amendment 31 19F.12 9309210212 930913 PDR ADOCK 05200001 A

PDR v \

gr s 23A6100 Cev.1 i . .ABWR / -- m s '= ^-- w ny:n -

is) A demonstra&m of; lenA. L p nes.r under ste. severe .u:,,xge,j _

~

Conladment pressare and ten.re,-adure .2ea49: de.rc&s e d Qfase ck*n 19 F. 3 1. 2 ._ _ -

(2) A simplified one-line diagram showing the locadon of the protective devices in the penetration circuit, with indication of the maximum available fault

/ current of the circuit; (3) Specific identification and location of power supplies used to provide external control power for tripping primary and backup electrical penetration '

breakers (if utilized);

)

i (4) An analysis demonstrating the thermal capabtiity of all penetrations is  ;

l preserved and protected by one of the following:

(a) The maximum available fault current (including single-failure of an f

upstream device) is less than the maximum continuous current capacity

{ I of the penetration; or (b) Redundant circuit protection devices are provided, and are adequately designed and set to interrupt current,in spite of single-failure, at a value i below the maximum continuous current capacity of the penetradon.

Such devices must be located in separate panels or be separated by barriers and must be independent such that failure of one will not adversely affect the other. Furthermore, they must not be dependent on

\

q the same power supply.

Protective devices designed to protect the penetrations are capable of being tested, calibrated and inspected (Subsection 8.3.4.4).

Se.e ,

8.3.3.8 Fire Protection of Cable Systems The basic concept of fire protection for the cable system in the ABWR design is that it is incorporated into the design and installation rather than added onto the systems. By use of fire resistant and non-propagating cables, conservative application in regard to

{ Cl1{) ampacity radngs and raceway fill, and by separation, fire protection is built into the

( systemgire suppression systems (e.g., automatic sprinkler systems) are provided as listed in Table 9.5.1 1. ,

8.3.3.8.1 Resistance of Cables to Combustion The electrical cable insulation is designed to resist the onset of combustion by limiting )

cable ampacity to levels which prevent overheating and insulation failures (and resultant possibility of fire) and by choice ofinsulation andjacket materials which have flame-resistive and self-extinguishing characteristics. Polyvinyl chloride or neoprene cable insulation is not used in the ABWR. All cable trays are fabricated from noncombustible material. Base ampacity rating of the cables was established as published in IPCEA-46-426/IEEE-S 135 and IPCEA 54-440/ NEMA WC-51. Each coaxial cable, each single conductor cable and each conductor in multiconductor cable is specified to pass the vertical flame test in accordance with UIA4.

93'T Onsorn PowerSystems- Amendment 31

.