ML20034G702

Forwards SSAR Markups for Subsections 3.6-2,3.6-3,3.6-4 & 3.6-5,in Support of Accelerated ABWR Review Schedule for SSAR Section 3.6

ML20034G702
Person / Time
Site:	05200001
Issue date:	03/02/1993
From:	Fox J GENERAL ELECTRIC CO.
To:	Poslusny C Office of Nuclear Reactor Regulation
References
NUDOCS 9303110053
Download: ML20034G702 (18)

Text

).

GE Nuclear Energy 6e w necccx;wy 175 lano Avense. Sinn Jose. CA liS125 l

March 2,1993 Docket No. STN 52-001 i

l l

Chet Poslusny, Senior Project Manager Standardization Project Directorate Associate Directorate for Advanced Reactors and License Renewal Office of the Nuclear Reactor Regulation

Subject:

Submittal Supporting Accelerated ABWR Review Schedule - SSAR Section 3.6

Dear Chet:

Enclosed are the SSAR markups for Subsections 3.6-2,3.6-3,3.6-4 and 3.6-5.

Sincerely, t ay Jack Fox Advanced Reactor Programs cc: Paul Chen (ETEC)

Norman Fletcher (DOE)

Maryann Herzog(GE)

Shou Hou (NRC) j 1

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9303110053 930302 PDR -ADOCK 05200001 A

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Sem=, lard Plant t-arv. s (ixed end and at the location supported by the r'estraint.

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t Effecks of re consider-ed negligible. pipe shear deflectio The pipe-bendin. oment-deflec-tion (or rotlttion) relation u d for these loca-tions is obtained from static nonlinear 34.2.3 Dynamic Analysis Methods to Verify i

cantilever-beam la lysis.

sing the moment-ro-Integrity and Operability r

equations of motion of tation relation, non e the pipe are formul d using energy considera-tions and the equa ' ns he numerically integrat-steps to\\ eld time-history of,34.2.3.1 Jet lapingement Analyses and i

Effects on Safety Related Components ed in small tim the pipe moti The methods used to evaluate the jet effects The pi ng stresses in'th containment resulting from the postulated breaks of high.

penetrati n areas are calculated the ANSYS energy piping are described in Appendices C and comput program, a program as crited in D of ANSI /ANS 58.2 and presented in this-Appe tx 3D. The program is used to form the. subsection.

Ann-near analysis of a piping system time ying displacements and forces d gro The criteria used for evaluating the effects v

ostulated pipe breaks.

of fluid jets on essential structures, systems, and components are as follows:

I (1) Essential structures, systems, and compo-nents are not impaired so as to preclude es-sential functions. For any given postulat-ed pipe break and consequent jet, those es.

} sential structures, systems, and components M01.gcetrto safely shut down the plant are t

identified.

1 (2) Essentist structures, systems, and compo.

[

nents which are not necessary to safely shut down the plant for a given break are not protected from the consequences of the fluid l jet.

(3) Safe shutdown of the plant due to postulated pipe ruptures within the RCPB is not A

aggravated by sequential failures of safety-related piping and the required emergency cool,ng system performance is ~

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Ofe '. EdffOe't da-fE hr maintained.

i AMS//ANS STr.2 E

[5 YccI Yd 8h (4) Offsite dose limits specified in 10CFR100 are complied with.

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(5) Postulated breaks resulting in jet j-impingement loads are assumed to occur in high-energy lines at full (102%) power 'l operation of the plant.

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(6) Throughwallleakage cracks are postulated in moderate energy lines and are assumed to 3 6-15 I

Amendment 21 l

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eww-

d M

23A6100AC =.

Standard Plant ma c.

TABLE 1.8-21 (Continued) i INDUSTRIAL CODES AND STAhTARDS.

APPLICABLE TO ABWR i

Code or 1

Standard i

Number Year

'Dtle ANS

~I l

2.3 1983 Standard for Estimating Tornado and Other Extreme Wind Charaderistics at Nuclear Power Sites

{

2.8 1981 Determining Design Basis Flooding at Power Reactor Sites 5.1 1979.

Decay Heat Power in LWRs i

18.1 (N237) 1984 Radioactive Source Term for Normal Operation of LWRs 52.1 1983 Nuclear Safety Design Cri;eria for the Design of Stationary Boiling Water Reactor Plants t

55.4 1979 Gaseous Radioactive Waste Processing Systems for Light Water Reactors l'

57.1 1980 Design Requirements for LWR Fuel Handling Systems j

57.2(N270) 1976 Design Requirements for LWR Spent Fue'. Storage I

Facilities at NPP

.j i

y 58 2 1988 Design Basis for Protection of Light Water NPP Against Effects of Postulated Pipe Rupture 59.51 (N195) 1976 Fuel Oil Systems for Standby Diesel-Generators -

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l' 1.8 33 Amendment 12__

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ABM 2346 oore Standard Plant REV.B result in wetting and spraying of essential (7) The distance of jet travel is divided into structures, systems, and components.

two or three regions. Region 1 (Figure

('

3.6-3) extends from the break to the

(

(7) Reflected jets are considered only when asymptotic area. Within this region the

~

there is an obvious reflecting surface (such discharging fluid flashes and undergoes as a flat plate) which directs the *,t onto expansion from the break area pressure to an essential equipment. Only the first the atmospheric pressure. In Region 2 the reflection is considered in evaluating jet expands further. For partial separa-potential targets, tion circumferential breaks, the area increases as the jet expands. In Region 3, (8) Potential t'argets in the jet path are con-the jet expands at a half angle of 10.

sidered at the calculated final position of (Figures 3.6-3a and c.)

the broken end of the ruptured pipe. This selection cf potential targets is considered (8) The analytical model for estimating the adequate due to the large number of breaks asymptotic jet area for subcooled water and analyzed and the protection provided from saturated water assumes a constant jet the effects of these postulated breaks.

area. For fluids discharging from a break which are below the saturation temperature The analytical methods used to determine which at the corresponding room pressure or have targets will be impinged upon by a fluid jet and a pressure at the break area equal to the the corresponding jet impingement load include:

roon pressure, the free expansion does not occur.

(1) The direction of the fluid jet is based on the arrested position of the pipe during (9) The distance downstream from the break steady-s' ate blowdown.

.where the asymptotic area is reached t

(Region if) is calculled for circum-(2) The impinging jet proceeds along a straight ferential' and longitadinal breaks.

path.

J 3,fi wf C 3 (3) The total impingement force acting on any cross-sectional area of the jet is time and distance invariant with a total.nagnitude equivalent to the steady-state fluid hCM W

blowdown force given in Subsection 3.6.2.2.1 and with jet characteristics shown in Figure (10) Both longitudinal a fully separated 3.6-3.

circumferential bre kLare treated similarly. The value of"

.used in the (4) The jet impingement force is uniformly blowdown calculation is used for jet distributed across the cross-sectional area impingement also.

of the jet and only the portion intercepted by the target is considered.,

(11) Circumferential breaks with partial (i.e.,

h<D/2) separation between the two ends of (5) The break opening is assumed to be a circu-the broken pipe not significantly offset lar orifice of cross-sectional flow area (i.e., no more than one pipe w-Il thickness equal to the effective flow area of the lateral displacement) are more clifficult to break.

(6) The jet impingement force is equal to the steady-state value of the fluid blowdown force calculated by the methods described in Subsection 3.6.2.2.1.

(

3.6-16 Amendment 23

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- Standard Plant any n quanti,fy. For these cases, the following

• assumptions are made.

l (a)

The jet is uniformly distributed around the periphery.

(b) The jet cross section at any cut through (12)

Target loads are determined using the the pipe axis has the configuration following procedures.-

depicted in Figure 3.6-3b and the jet regions are as therein delineated.

(a) For both the fully. separated circumferential break and the (c)

The jet force F. = total blowdown F.

longitudinal break, the jet is studied 3

by determining target locations vs.

(d)

The pressure at any point intersected by asymptotic distance and - ;'.._; l the jet is:

ANSI /ANS 58.2, Appendices C and D.

..k 5 m

tseget saye fachs F.

^^3 g

jud as ca/aMed' where

[pcg.

y p((g{ly(t (N)$A the M4469 area of the jet at a A<g =

radius equal to the distance from the l

)

pipe centerline to the target cate#\\cked 'in accewdame e wi+g pgS3jpns gg,z, ppy,cy//y ( *

(c)

The pressure of the jet is then multiplied by the area of the target submerged within the jet.

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(b) For circumferential break.with limited separation, the jet is analyzed by-l-c using the equations of ANSI /ANS $8.2, l

i Appendices C and D and determing respective target and asymptotie l locations

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i 3 6-17 i

Amendment 23

.MN 23A6100AE Standard Plant uv. 8 e) 'After determination of the total area of the D = pipe OD of target pipe for a fully jet at the target, the jet pressure is submerged pipe.

I calculated by:

When the target (pipe) is larger than the area F.

of the jet, the effective target area equals the 1

expanded jet area P

=

1 A*

A

=A te x

where (3) For all cases, the jet area (A ) is as-P=

incident pressure sumed to be uniform and the* load is 7

uniformly distributed on the impinged target A, =

area of the expanded jet at the area A target intersection.

TatyeV shpe factors Me includekk modwe d%

If the effective target area (A ) is less than ArJst//)Ns 50,2.

expanded jet area (A e < A ), the target is t

fully submerged in the jet andibe impingement load is equal to (P 3) (A if the effective target area is greater Ifa)n expanded jet area (A** > A ), the target intercepts the entire jet and the* impingement load is equal 3.6.2.3.2 Pipe Whip Effects on Essential to (P ) (A ) = F..

The effective target Components areafA )ior var $ous geometries follows:

This subsection provides the criteria and (1) Flat surface - For a case where a target methods used to evaluate the effects of pipe with physical area A is oriented at angle displacements on essential structures, systems,

,,APwith respect to the, jet axis and with no end components following a postulated pipe

[L flow rsal he effective target area rupture.

Pipe whip (displacement) effects on essential structures, systems, and components can be

,) 4 - (Ay (a4 placed in two categories: (1) pipe displacement effects on components (nozzles, valves, tees, etc.) which are in the same piping run that the (2) Pipe Surface As the jet hits the conver break occurs in; and (2) pipe whip or controlled surface of the pipe,its forward momentum is displacements onto external components such as decreased rather than stopped; therefore, building structure, other piping systems, cable the jet impingement load on the impacted trays, and conduits, etc.

area is expected to be reduced. For conservatism, no credit is taken for this 3.6.2.3.2.1 Pipe Displacement Effects on reduction and the pipe is assumed to be Components _in the Same EipingRun impacted with the full impingement load.

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'The criterialor cetermining the effects of

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d. The pipe displacements on inline components are as effective target area A f ll **

te A

= (D )(D)

(1) Compon:nts such as vessel safe ends and te valves which are attached to the broken piping system and do not serve a safety where function or failure of which would not D

= diameter f the jet at the further escalate the consequences of the target interf ace, and accident need not be designed to meet ASME A

3618 Amendment 21

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ABM mm

>1 Standard Plant 3

gesf n Code Section III imposed limits for essential ilure in a piping system carrying high-er components under faulted loading.

fl 'd. In the ABWR plant, the piping inr,e)ergygrity do not depend on the pipe whip restraints for (2) If these components are required for safe any iping design loading combination ideluding shutdown or serve to protect the structural carth uake but shall remain functional f5110 wing hquake up to and including the " SE (See integrity of an essential component, limits an ca to meet the ASME Code requirements for Subsec 'on 3.2.1). When the piping i tegrity is faulted conditions and limits to ensure lost be use of a postulated break the pipe 3

required operability are met.

whip rest 'nt acts to limit the moverdent of the broken pi to an acceptable distan'c/. The pipe The methods used to calculate the pipe whip whip restra ts (i.e., those devices,which serve loads on piping components in the same run as the only to cont I the movement of a fuptured pipe t

postulated break are described in Section following gr s failure) will be/ subjected to 3.6.2.2.2.

( once-in a life "me loading. For e purpose of I the pipe whip estraint design, e pipe break 3.6.2.3.2.2 Pipe Displacement Effects on is considered. o be a faulted ondition (See Essential Structures, Other Systems, and Subsection 3.9.

1.1.4) and,1 e structure to Components which the restry at is attache is also analyzed and designed a, cordingly. The pipe whip The criteria and methods used to calculate the restraints are nq -ASMEj ode components; effects of pipe whip on external components however, the ASME-e req rements are used as consists of the following:

optional in the de *gn seje tively to assure its f

safety-related func 'on.

ther methods, i.e.

The effects on essential structures and bar- } testing, with a reli ble/ata base for design g

(1) riers are evaluated in accordance with the ' and sizing of pipe w 'p*r straints can also be barrier design procedures given in Subsec-used.

f tion 3.5.3 The pipe whip res r ints utilize energy ab-t (2) If the whipping pipe impacts a pipe of equal ; sorbing U-rods to at[e

'te the kinetic energy or greater nominal pipe diameter and equal of a ruptured pipe. A ypical pipe whip re-or greater wall thickness, the whipping pipe straint is shown in fi ure

.6-6.

The principal does not rupture the impacted pipe. Other. I feature of these res raints is t, hat they are in.

(

wise, the impacted pipe is assumed to be stalled with severa'l nches o annular clearance g

ruptured, between them and he proce pipe. This allows

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for installation of ormal pipi g insulation and I

(3) If the whipping pipe impacts other compo-for unrestricted pc thermal ovements during

[

nents (valve actuators, cable trays, con-plant operation Select critica locations in-1 3

duits, etc.), it is assumed that the im-side primary'c ntainment are a so' monitored

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pacted component is unavailable to mitigate during hot fun.tional testing to p ovide verifi-the consequences of the pipe break event.

cation of d quate clearances p ior to plant i operation he specific design ob e'tives for 1

c (4) Damage of unrestrained whipping pipe on es- ( the restrain s are:

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(1) The,.[r straints shall in no way in sential structures, components, and systems ~

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ease the other than the ruptured one is prevented by either separating high energy systems from react r coolant pressure boundary tresses the essential systems or providing pipe whip byjt eir presence during any normal ode of f

restraints.

rea tor operation or condition;

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(2)[he movement of a pipe failure (gross oss f

f e restraint system shall function to tp 31 Leading Combinations and j

e Criteria orgi Whip Restral

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/ of piping integrity) without allowing dam e

s, as differentiated from to critical components or missile develo,.

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j Pipe whip ptt in(Esi'gned to function and ment; and kf piping rts, are d

~ bability gross d for an extremely 15

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3N Amendment 23

.'AB M

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Standard Plant A

ney. n (3) The restraints should provide minim m

'ndrance to inservice inspection o the

(

p :ess piping.

For the urpose of design, the ape whip restraints ar esigned for the foll ing dynamic loads:

(1) Blowdown th st of th 5pe section that impacts the res aint '

i (2) Dynamic inertia i ds of the moving pipe

- section which is a el ated by the blowdown j

thrust and s sequ t impact on the i

restraint; (3) Design ch racteristics o he pipe whip restraint are inctoded and crified by the l

pipe w dynamic analysis scribed in i

Subse non 3.6.2.2.2; and j

(4) Sin e the pipe whip restraints e not acted during normal plant operatio the l

co p stulated pipe rupture event is the ly sign loading condition.

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3620 Amendment 21 -

NevJ SesfiM

3. 6. 2.3. 3 3.6.2.3.3 Design Criteria and Load (2) Restraints with Crushable Material - Pipe Combinations for Pipe Whip Restraints, whip restraints with crushable material have the same design basis as the U-bar restraint. It is a The loading combinations and design single purpose, energy absorbing restraint with criteria for pipe whip restraints is dependent sufficient gap between the pipe and the restraint to on the type of restraint and the function it allow free thermal expansion of the pipe. Restraints performs. Some restraints in the ABWR are with crushable pads may not have lateral load designed to perform a dual function of capability so they must be provided in every supporting the pipe during operating conditions direction in which the jet thrust from the ruptured and also controlling the motion of the pipe pipe may occur. Figure 3.6-5 illustrates several following a postulated rupture. However, most acceptable pipe whip restraint designs using crushable material: the crushable ring, the pipe whip restraints in the ABWR are single honeycomb restraint, and the frame with series of purpose restraints designed to control the motion of a broken pipe.

crushable rings.

Figure 3.6.5 illustrates some acceptable (3) Rigid Restraints - Rigid pipe whip restraints are pipe whip restraint designs. These designs dual purpose, essentially clastic restraints that take the form of seismic guides, struts, and structural 4

include:

frames. Since rigid restraints are attached to the (1) The U-bar restraint - This is a single pipe or are separated from the pipe by very small purpose, energy absorbing restraint gaps, they carry loads caused by thermal expansion, designed for once-in a-lifetime loading.

dead weight, seismic and other dynamie events The gap between the. pipe and the restraint during plant operation. Rigid restraints therefore is relatively large to permit free thermal serve a pressure integrity function and are expansion of the pipe and does not provide considered as pipe supports that must meet the support to maintain structural integrity of requirements of ASME III, Subsection NF. They the pipe during any of the plant operating are modeled as rigid 4Teiiients in the static and ~5vkg f

conditions. Most of the restraints used in dynamic analysis of the piping. Following a J

the ABWR plar.t on large ASME Class 1 postulated pipe rupture these restraints carry the piping are U ban restraints with stainless load from the jet thrust and control motion of a steel U-bars, this restraint is further broken pipe. These restraints are designed to stort defined in this Subsection and serves as the pipe without exceeding ASME III,* Level D 4s,

the basis for the Appendix Wjirocedure fori limits. The seismic guide provided on the main evaluation of postulated ruptures in high steam and feedwater pipe serves a rigid pipe whip energy pipes. Although piping integrity restraint performing a dual function.

does not depend on this single purpose pipe whip restraint, the restraint shall be The specific design objectives of pipe whip designed to remain functional following an restraints are:

earthquake up to and including the SSE (See Subsection 3.2.1) This pipe whip restraint (1) Single purpose restraints shall in no way is further illustrated in Figure 3.6-6.

increase the reactor coolant pressure boundary stresses by their presence during any normal mode of reactor operation.

.c NM

~

N J,f. z.3,3 (2) The restraint system shall function to stop

'the movement of a ruptured pipe without allowing damage to critical components or missile development; and (3) The restraints should p:; permit 1

53.

imm um" -

l

.J1.:..d:;;a te inservice inspection of the process pipmg.

4 For the purpose of design, the pipe whip restraints are designed for the following dynamicloads:

?

(1) Blowdown thrust of the pipe section that l

impacts the restraint; (2) Dynamic inertia loads of the moving pipe section which is accelerated by the blowdown thrust and subsequent impact of the restraint; Mon-linew-(3)Eesign characteristics of the pipe whip restraints are included and verified by the pipe whip dynamic analysis described in i

Subsection 3.6.2.2.2 and Appendir 30 L (4) Since single purpose pipe whip restraints are not contacted during normal plant I

operation,'the postulated pipe rupture

• i

-i event is the only design loading condition; an'd (5) For unruptured pipe, dual purpose pipe whip restraints act as ASME III, Subsection NF pipe supports and must meet the Code requirements for service. loads and load

,i combinations for unruptured pipe specified in the design' specification and summarized '

.in Table 3.9 2. Following postulated pipe rupture, the restraint stress must not I

exceed ASME III,4,evel D limits for pipe dsee/ ins A rupture loads acting irt co-Wn.h,ow with lo.Any for dica yevoic e. -

l AWE!' 4 blh' MC ped ((

CONTINUE AS ON PAGE 3.6-22 u

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,,-ic 4

4

l ABWR

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Standard Plant nrv n 3.6.2.4 Guard Pipe Assembly Design The ABWR primary containment does not require guard pipes.

3.6.2.5 Material to be Supplied for the Operating License Review See Subsection 3.6.4.1 for COL license information requirements 3.6.3 Leak-Before Break Evaluation Procedures Strain rate effects and other material Per Regulatory Guide 1.70, the safety I property variations have been considered in the analysis Section 3.6 has traditionally addressed design of the pipe whip restraints. The material the protection measures against dynamic effects properties utilized in the design have included associated with the non-mechanistic or one or more of the following methods:

postulated ruptures of piping. The dynamic effects are defined in introduction to Section.

(1) Code minimum or specification yield and 3.6. Three forms of piping failure (full flow ultimate strength values for the affected area circumferential and longitudiaal breaks, components and structures are used for both and throughwallleakage crack) are postulated in the dynamic and steady-state events; accordance with Subsection 3.6.2 and Branch Technical Position MEB 3-1 of NUREG - 0800 (2) Not more than a 10% increase in minimum code (Standard R : view Plan) for their dynamic as well or specification strength values is used as environmental effects.

when designing components or structures for the dynamic event, and code minimum or However, in accordance with the modified specification yield and ultimate strength General Design Criterion 4 (GDC-4), effective values are used for the steady-state loads:

November 27,1987 - (Reference 1), the mechanistic leak-before-break (LBB) approach, t

(3) Representative or actual test data values justified by appropriate fracture mechanics are used in the design of components and techniques, is recognized as an acceptable structures including justifiably clevated procedure under certain conditions to exclude strain rate affected stress limits in excess design against the dynamic effects from of 10%; or postulation of breaks in high energy piping.

The LBB approach is not used to exclude (4) Representative or actual tcst data are used postulation of cracks and associated effects as for any affected component (s) and the required by Subsections 3.6.2.1.5 and t

minimum code or specification values are 3.6.2.1.6.2. It is anticipated, as mentioned in used for the structures for the dynamic and Subsection 3.6.4.2, that a COL applicant will the steady-state events.

annly to the NRC for approval of LBB qualifica-tion of selected piping. These approved piping, referred to in this SSAR as the LBB-qualified piping, will be excluded from pipe breaks, which 3 4-22 Amendment

hk 23A6100AE Standard Plant arv s are required to be postulated by Subsections 3.6.1 and 3.6.2, for design against their potential dynamic effects.

1 The following subsections describe (1) certain I

design bases where the LBB approach is not recognized by the NRC as applicable for exclusion of pipe breaks, and (2) certain conditionr. which limit the LBB applicability. Appendix 3E i

provides guidelines for LBB applications l

describing in detail the following necessary elements of an LBB report to be submitted by a COL applicant for NRC approval; fracture mechanics methods, leak rate prediction methods, leak detection capabilities and typical special considerations for LBB applicability. Also included in Appendix 3E is a list of candidate piping systems for LBB qualification. The LBB application approach described in this subsection and Appendix 3E is consistent with that documented in Draft SRP 3.6.3 (Reference 4) and NUREG-1061 (Reference 5). (See Subsection 3.6.4.2 for COL licens e in f o r m a tio n requirements.)

i i

Amendment 3.6 22.1

BW 23A6100AE Standard Plant nev n 3.63.1 Scope of LBB Applicability chanisms are not potential sources of pipe rupture The LBB approach is not used to replace existing regulations or criteria pertaining to (2) The ABWR plant design involves operation 0

the design bases of emergency core cooling system below 700 F in ferritic steel piping and 0

(Section 6.3), containment system (Section 6.2) below 800 F in austenitic steel piping.

or environmental qualification (Section 3.11).

This assures that creep and creep-fatigue Howeser, consistent with modified GDC-4, the are not potential sources of pipe rupture.

design bases dynamic qualification of mechanical and electrical equipment (Section 3.10) may (3) The design also assures that the piping exclude the dynamic load or vibration effects material is not susceptible to brittle resulting from postulation of breaks in the cleavage-type failure over the full range of LBB-qualified piping. This is also reflected in system operating temperatures (that is, the a note to Table 3.9-2 for ASME components. The material is on the upper shelf).

LBB-qualified piping may not be excluded from the design bases for environmental qualification (4) The ABWR plant design specifies use of unless the regulation permits it at the time of austenitic stainless steel piping made oi LBB qualification. For clarification, it is material (e.g., nuclear grade or low carbon noted that the LBB approach is not used to relax type) that is recognized as resistant to the design requirements of the primary IGSCC. The >

najor high energy containment system that includes the primary piping in the and secondary 2

steel or ferritic containment vessel (PCV), vent systems (vertical containments.

c flow channels and horizontal vent discharges),

steel, except for '

.ustenitic stainless drywell zones, suppression chamber (wetwell),

reactor water cleanup eiping in the primary vacuum breakers, PCV penetrations, and drywell containment.

head.

(5) A systems evaluation of potential water 3.63.2 Conditions for LBB Applicability hammer is made to assure that pipe rupture due to this mechanism is unlikely. Water The LBB approach is not applicable to piping hammer is a generic term including various systems where operating experience has indicated unanticipated high frequency hydrodynamic particular susceptibility to failure from the events such as steam hammer and water effects of intergrannular stress corrosion slugging. To demonstrate that water hammer cracking (IGSCC), water hammer, thermal fatigue, is not a significant contributor to pipe or erosion. Necessary preventive or rnitigation rupture, reliance on historical frequency of l

measures are used and necessary analyses are water hammer events in specific piping i

performed, as discussed below, to avoid concerns systems coupled with a review of operating for these effects. Other concerns, such as procedures and conditions is used for this creep, brittle cleavage type failure, potential evaluation. The ABWR design includes indircr4 source of pipe failure, and deviation of features such as vacuum breakers and jockey as-built piping configuration, are also pumps coupled with improved operational addressed, procedures to reduce or eliminate the pot-ential or water hammer identified by pa (1) Degradation by crosion, erosion / corrosion and erosion /cavithtion due to unfavorable flow conditions and water chemistry is examined. The evaluation is based on the industry experience and guidelines.

Additionally, fabrication wall thinning of elbows and other fittings is considered in the purchase specification to assure that the code minimum wall requirements are met.

These evaluations demonstrate that these me-5 34 23 Amendment

AMM 23461oore Standard Plant Rev n experience. Certain anticipated water hammer events, such as a closure of a valve, are accounted for in the Code design and analysis of the piping.

(6) The systems evaluation also addresses a po-tential for fatigue cracking or failure from thermal and mechanical induced fatigue.

Based on past experience, the piping design avoids potential for significant mixing of high-and low-temperature fluids or mechanical vibration. The startup and preoperational monitoring assures avoidance of detrimental mechanical vibration.

(7) Based on experience and studies by Lawrence Livermore Laboratory, potential indirect sources of indirect pipe rupture are remote causes of pipe rupture. Compliance with the snubber surveillance requirements of the technical specifications assures that snubber failure rates are acceptably low.

(8) Initial LBB evaluation is based on the design configuration and stress levels that are acceptably higher than those identified i

by the initial analysis. This evaluation is reconciled when the as-built configuration is documented and the Code stress evaluation is reconciled. It is assured that the as built configuration does not deviate significantly from the design configuration to invalidate the initial LBB cvaluation, or a new evaluation coupled with necessary configuration modifications is made to assure applicability of the LBB procedure.

3h24 Amendment i

ABWR 23A6100AE Standard Plant nrv.n l

i 3.6-25 Amendment

r ABM 23^""

Standard Plant REV,R 1

h 7

3 626 Amendment

y

, MM 23A6100AE Standard Plant REV.B-(1) A summary of the dynamic analyses l

applicable to high-energy piping 3*gg ggg systems in accordance with Subsection 3.6.2.5 of Regulatory Guide 1.70. This shall include:

(a)- Sketches of applicable. piping systems showing the location, size and orientation of postulated pipe -

breaks and the location of pipe whip restraints and jet impingement barriers.

- (b) A summary of the data developed to select postulated break locations including calculated stress intensities, cumulative usage factors and stress ranges as -

delineated in BTP MEB 3-1

/'

as enelifie/by Schsediony.g,}g f (2) For failure in the moderate-ene y

piping systems listed in Tabic $.6-6, descriptions showing how safety-related -.

systems are_ protected from the' resulting jets, flooding and other adverse environmental effects.

(3) Identification of protective measures

)

provided against the effects of postulated pipe failures for protection of each of the systems listed in Tables 3.61 and 3.6-2.

(4) The details of how the MSIV functional ~-

capability is protected against the effects of postulated pipe failures.

(5) Typical examples, if any, where protection for safety-related systems and components against the dynamic

~

. effects of pipe failures include their enclosure in suitably designed structures or compartments (including any additional drainage system or.

g equipment environmental qualification i

3.6 COL License Information needs).

Sma/Y 3.6.

1 Dstaffh of Pipe Break Analysis Results (6) The details of how the feedwater line -

and Protection Methods check and feedwater isolation valves functional capabilities are protected The following shall be provided by the COL against the effects of postulated pipe-applicant (See Subsection 3.6.2.5):

failur"

$22 h 0

3627 Amendment 23 i

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/

Aff,8 4

3.6.4 As-Built Inspection of High Energy Pipe Break Mitigation Features An as-built inspection of the high energy pipe break mitigation features shall be performed. The as-built inspection shall confirm that systems, structures and components, that are required,'to be functional during and following an SSE, are protected against the dynamic effects associated with high energy pipe breaks. An as-built inspection of pipe whip restraints, jet shields, structural barriers and physical separation distances shall be performed.

For pipe whip restraints and jet shields, the location, l

orientation, size and clearances to allow for thermal expansion I

shall be inspected. The locations of structures, identified as a pipe break mitigation feature, shall be inspected. Where physical separation is considered to be a pipe break mitigation feature, the assumed separation distance shall be confirmed during the inspection.

l 3.6.5 COL License Information 3.6.5.1 Details of Pipe Break Analysis Results and Protection Methods (7)

An inspection of the as-built high energy pipe break i

mitigation features shall be performed. The pipe break l

analysis report or leak-before-break report shall document l

the results of the as-built inspection of the high energy pipe break mitigation features. (See subsection 3.6.4, for a summary of the as-built inspection requirements.)

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