ML17276A998

Forwards Draft Response to NRC Question 130.050 (Turbine Missile Study) & Revised FSAR Pages.All Encl Info Will Be Incorporated Into Amend 23

ML17276A998
Person / Time
Site:	Columbia
Issue date:	01/13/1982
From:	Bouchey G WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	Schwencer A Office of Nuclear Reactor Regulation
References
GO2-82-33, NUDOCS 8201290321
Download: ML17276A998 (37)

Text

REGULATORY ORMAT ION DISTRIBUTION 'SYS

('R IDS)

AOCES SION NBR: 8201290321 DOC, DATE! 82/01/13 NOTARIZED:

NO DOCKET.

FACIL:50 397 WPPSS Nuclear Pr ojecti Unit 2~ Washin'gton 'Public Powe 05000397

'AUTHBNAME AUTHOR AFFILIATION BOUCHEY<G,D, Washington Public iPower "Supply System

'RBCIP ~ NAME RECIPIENT AFFILIATION SCHWENCEREA ~

Licensing Branch '2 SUBJEOT:

Forwards draft-..response

>to NRC Question 130.050 (turbine missile study) 8 Trevised FSAR pages'll Tencl info will be incorporated into Amend 23.

DISTRIBUTION CODE:

BOOIS tCOPIES iRECEIVED:L'TR,J. ENCL.

I SiZe:

TITLE: PSAR/FSAR AMDTS and Related ICorrespondence NOTES:2 copies all matl:PM'5000397 RECIPIENT ID CODE/NAME ACTION:

A/D LICENSNG LIC BR ¹2 LA INTERNALR ELD IE/DEP/EPDB

'35 MPA NRR/DE/EQB 13 NRR/DE/HGEB 30 NRR/DE/MiTEB 17 NRR/DE/SAB

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'23 FI 04 EXTiERNAL: ACRS 41 FEMA REP DI V 39 NRC PDR 02 NTI'

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820f2'P032f 820ff3 PDR ADOCK 05000397 A

PDR Washington Public Power Supply System P.O. Box 968 3000George Washington Way Richland, Washington 99352 (509) 372-5000 January 13, 1982 G02-82-33 SS-L-02-CDT-82-013 Docket No. 50-397 Mr. A. Schwencer, Chief Licensing Branch No.

2 Division of Licensing U.S. Nuclear Regulatory Commission Was hi ng ton, D.C.

20555

Subject:

NUCLEAR PROJECT NO.

2 NRC QUESTION 130.050 TURBINE MISSILE STUDY Enclosed are sixty (60) copies of the draft response to NRC Question 130.050 and revised WNP-2 FSAR pages.

This response shows the results of the turbine missile study for WNP-2.

All enclosed i nformation will be incorporated into the WNP-2 FSAR in Amendment 23.

Very truly yours, G.

D. Bouchey, Deputy 'ctor Safety

& Security CDT/jca Enclosures cc:

R Auluck -

NRC WS Chin

- BPA R

Fei 1 NRC Si te go&

5 l

I

\\

l k'I 4

ll h

>, 1

(

1 C

~ -.r.

rQ-

~

WNP-2 Q.

130.050 (Q220.001)

(3.5.1)

You state in Section 3.5.1.3 of the FSAR that the reorientation of the turbine generator building to limit potentia l missile strike is not considered.

Ratherr the barrier capability. of the massive radiation shielding structuresr characteristic of BWRsr is utilized to control postulated turbine missile hazardsi and probability studies provide the assurance that the chance of missile strike is remote.

Describe your probabi lity st of turbine missiLe strike an barrier.

If in your analysi 1.0i please so indicate.

udies with emphasis on the chance d penetration of the structuraL s the value of P3 is assumed as

Response

WNP-2 has completed a turbine missile study consisting of a

probabilistic approach to missile strikes and damage.*

• Revised FSAR page changes attached.

WNP-2 AMENDMENT NO.

9 April 1980 3.5.1.3

'Turbine Missiles The orienta

'on of the turbine qenerator building with respect to other str tures was established prior to the pr mulgation of Requlatory guide 1.115, Rev. 0, (Reference 3.5

).

Conse-

quently, the reorientation of the turbine gener or building to limit potential missile strike is not consi ered.

Rather, the barrier capab'lity of the massive radiatp n shielding structures, chara teristic of BWR's, is ut'sized to control postulated turbine issile hazards, and p obability studies provide the assuran e that the chance o

missile strike is remote.

3.5.1.3.1 Turbine Pl cement and Orientation f

Fiqure 3.5-33 delineate the turbine-generator layout relative to safety related plant structu s

and turbine missile target areas.

The probable miss le e,'ection

zones,

+

25 degrees,to the horizontal plane of th end turbine disks, are clearly shown.

An elevation view is/'included in Fiaure 3.5-34 to further portray tarqet zon 3.5.1.3.2 Missile Iden ification and Characteristics Turbine missiles are postulated to oriqinate from low pressure turbines of Westinghouse design t 193% catastrophic oversaeed.

Westinghouse (Refere ce 3.5-6) concludes that the

,/

hiqh pressure turbine does not qe crate missiles.

Due to a

larqe margin between the high pres ure spindle bursting speed and the max'imum speed at which the steam can drive the unit with all the admission valves fully open, the probability of swindle failure~is practically zero.

The minimum bursting speed of the high speed rotor, based n minimum specified mechanical properties of the rotor ma erial, is 300$ of the rated speed /

The maximum speed to whi h the unit may accel-erate is 19'%f rated speed.

At this speed the hiqhest stiessed low pressure turbine disc will fracture.

The fracture traumenta/will, upon failure, damaee the turbine to the extent that additional overspeed will'ot be po sible (Reference

3. 5-6). j

3. 5-12

WNP-2 AMENDMHNT NO ~

9 April 1980 The characteristic properties of these missile segments are pictured in Fiqure 3.5-35.

The mass,

shape, cross-ectional

area, and ranaed turbine exit speeds are presente in Table 3.5-3.

These specifications, in conjunction wit the math-ematical models and experimental tests used in he selection of missiles, are treated in a Westinqhouse do ument covering the effects of~a hiqh pressure turbine roto fracture and low pressure turbine disc fractures at des'qn and catastrophic overspeed (Reference 3.5-6).

3.5.1.3.3 Low Trajectory Missiles In the design of a BQR station, an tensive amount of re-inforced concrete is Msed for radi ion shielding.

As well as providinq a biological shield, his concrete provides structural barriers fo essentia systems against postulated low trajectory missiles.

Table 3.5-4 summarizes the, cu ulative concrete barriers separatinq critical shutdown systems from postulated turbine missiles.

The criteria used in detepmin nq turbine missile energies is contained in the 1978 We tingh use report (Reference 3.5-6).

The northernmost RHR heat exchan er is exposed to' possible turbine missR'le.

This R unit is redundant to a

more highly protected RHR heat exchanger on the southern side of the reactor buildinq between ele+ations 548 feet and 606 feet.

Furthermore/ the missile tra ctories necessary to im-pact the RHR heat/exchanqers are not directly in the plane of the turbine disks.

Consequently, ow trajectory turbine missiles cannot >impair safe shutdown because the concrete barriers and the redundancy feature pro'vide protection of the essential systems.

3.5.1.3.4 High Trajectory Missiles A probabalistic approach is adopted in orde to assess the possibility of damaqe to systems required for safe shutdown or of accidents which could result in potenti 1 offsite exposure

'due to hiqh trajectory missiles.

The probability of this occurrinq is represented by combined p

babilities of:

3. 5-13

0 I

5 s

WNP-2 AH 6 DNENT NO.

12 November 980 where:

P4

=

P1. P2.

P3 P1

= tur ine failure probability P2

= proba ility of a missile str'ng a structure or component required for s e shutdown or whose Eailure could result n release of radioactivity I

significanP damage "o tbst,ructure or component pro babi 1it P4

= combined ove all prob ility The terms and assumptions applicab e to this analysis follow the procedures outlined by S.gH.

ush in the report "Prob-ability of Damage to Nuclear m onents due to Turbine Failure",

November 1972 (Refer e 3.5-7).

a.

Turbine failure pro ability is directly related to proprietary de'sig, fabr ication, inspection, and testing specific ions (3.5.1.3.6, 3.5.1.3.7)

Thp abov procedures for Wes tinghouse a>>e super 'r to those utilized on a

" total sample qf turbines encompassing all manu-facturers sidhe the inception of the nuclear age.

Failure probablities bas d on all turbogenerating facilities do not adequat ly portray the Wes tinghouSe tur bi nes, in P-2.

The mos t repre-sentative fata pertaining turbine failure is derived from plant operatin experience with Westinghouse turbines.

The ited Westinghouse reports ylndicate the tur bine ailure probabili-

ties, P1, when the turbine is quipped with ana-log or digital electrohydrauli control systems, to be /.6 x 10 10/unit/year for design overspeed and 1

7 x 10 6/unit/year for des ructive over eed (Reference 3.5-15).

b.

The probability of structural pene ration and resultant damage to critical compon nts upon

impact, P3, is assumed to equal 1 si ce 'less than 3 /feet of structural materi als shiel targets om high trajectory missiles (Refere ce 3.5-7).

3. 5 0

g

-I

WNP-2 h

3.5.1.3 Turbine NissiLes Regulatory Guide 1.115 (Reference 3.5-5)i initially issued in 1976i required applicants for construction permits and operating Licenses to demonstrate an acceptably Low probability of damage to essentiaL systems from postulated turbine missilesi either through appropriate placement and orientation of the turbinei or by use of structura l barriers.

Subsequent lyi a study was performed by Burns and Roei Incorporated for the WflP-2 plant which concluded that the radiation shielding walLs on the oper-ating floor in the turbine buildingi and the reinforced concrete'a L L s housing essent i at systems in the reac to'r bui Lding and control buildingi provide adequate protection against postulated

,turbine missiles.

In December 1979i the Washington Public Power Supply System (Reference 3.5-24) and other utilities were advised by the NRC of a potential problem concerning cracking in Low'pressure turbine discs manufactured by Westinghouse.

In February 1980i a disc on the Westinghouse Low pressure turbine at the Yankee Rowe plant failedi and although none of the disc fragments penetrated the turbine shelLi there was extensive damage to the turbine.

Investigations by Westinghouse at various operating plants has indicated the observed cracking in Westinghouse turbines can be attributed to a stress-corrosion mechanism.

To account for this potentiaL failure mechanism in turbine-missile probabiLity calculationsi Westinghouse developed a

methodology for estimating the probabilities of disc rupture as a function of crack initiationi crack propogation with timer and critical crack depth (Reference 3.5-21).

Using this methodologyi Westinghouse provided a probability studyi giving missile generation probabilities for each Low pressure turbine disc on WNP-2i based on actual materia l properties of the disci as a function of turbine operating time between inservice inspections.

Probabilities are also calculated for missile formation due to fatigue failurei but this failure mode is shown to be much Less Likely than failure due to stress corrosion cracking.

Using the missile generation probabilities (Reference 3.5-23) and missile weightsi velocitiesi and geometries (Reference 3.5-22) p'rovided by Westinghousei missile strike and damage probabilities for safety-reLated targets in the WNP-2 plant were calculated.

It is concluded that the probability of damage to safety-related systems is acceptably Lowi due to:

(a) the protection provided by reinforced concrete structuraL barriersr and (b) periodic inspections of turbine discs during refueling outages to detect and monitor cracksi with associated corrective action as required.

3.5-12

0 I

WNP-2 3.5.1.3.1 Safety-Related Targets Target areas which are evaluated for capability to protect safety-related equipmentr compone'ntsr and systems from postu-Lated turbine missiles consist of the following:

a ~

Vertical Targets 1

~

2.

3.

reactor building north exterior waLL controL room north wall north waLL of verticaL cable chaser between reactor building and control room.

b.

Horizontal Targets 1., reactor building refueling floor 2.

roof over vert,icaL cable chase 3.

f Loor slab above controL room 3.5.1.3.2 Turbine Placement and Or i ent at i on I

Figure 3.5-33 shows the turbine generator Layout relative to safety-related plant structures and turbine missile target

'areas.

Also shown on this drawing is the reinforced concrete shiel'd wa L L which acts as a barrier for protection of some safet~y-related.targets from postulated Low trajectory turbine missiILes.

A cross-sectional view through the turbine building and reactor building is shown in Figure 3.534 to indicate relative elevations of the turbine and target areas.

See Figurie 1.2-5 for a general arrangement drawing of the turbine buildingr reactor buildingi and control building at the turbine operating fLoor elevation.

3.5.1.3.3 Missile Identification and Characteristics Postulated missiles from the high pressur in Reference 3.5-22'o have insufficient the ca's ing at normal operating speed.

At of normal'r rated speed) r high pressure postulated to penetrate the casingi but

- a to reach safety-related targets.

The min of the high pressure turbine rotors based mechanical. properties of the rotor materi rated speed.

e turbine are shown'"

energy to penetrate 20% overspeed (120%

turbine missiles are t velocities too Low imum bursting speed on minimum specified ale is 300% of the The maximum speed at which the unit may rotate is 193% of rated speed.

At this speed the highest stressed Low pressure turbine disc would fracturei damaging the turbine to the extent that additional overspeed would not be possible (Reference 3.5-13

t

WNP-2 exposure due to high trajectory missiles.

The probability of this occurring is represented by combined probabilities of:

4 1

2 3

where:

P1

= missile generation probability P2

= probability of a missile striking a structure or component required for safe shutdown or whose fai Lure could result in release of radioactivity P

= probability of significant damage to the struc-3 ture or component P4

= combined overaLL probabi l i ty The terms and assumptions applicable to this analysis follow the procedures outlined by S.

H. Bush in. the reporti "Prob" ability of Damage to Nuclear Components due to Turbine FaiLure"i November 1972 (Reference 3.5-7).

3-5-1 '.4.1 Ni'ssile Generation Probability (P1)

The probability of a

Low pressure turbine disci or associated blade ring fragment becoming a missile following disc rupture and penetration of the turbine casing is provided by Westinghouse in Reference 3.5-23.

P1 probabilities are given for each disc on each low pressure turbinei as a function of inspection intervaL (i.e.i turbine operating time between inspections for cracks)i for stress corrosion cracking.

In the analysis which produced these P1 valuesi it is assumed that a crack initiates at the beginning of service Life or immediately after an in-service inspection during a refueling outage.

For a given disci the probability of rupture due to stress corrosion is the probability that there exists a crack in the disc bore whose depth is equal to or greater than a calculated critical crack depth.

The critical crack depth is calculated using standard fracture mechanics methodologyi and is ba'sed on actual material properties for the disci and normal operating temper-atures for the turbine.

Data from field inspections are used to estimate the probability, of the existence of cracks in the various disc types'i and crack growth rates.

Using appropriate probabiLity distributions for crack growth rates and critical crack depthi a numerical analysis technique is used to calculate the probability of disc rupture.

This value is a function of 3.5-14a

WNP-2 3.5-6).

Thereforei high pressure turbine missiles are not considered.

Postulated Low pressure turbine missiles are assumed to result from either fatigue failure or stress corrosion crack-ing.

The probability of fatigue failure resulting in missile generation is several orders of magnitude Lower than the probability of stress corrosion failurei at either rated speed or 20% overspeed.

Thereforei only missile generation probabilities associated with stress"corrosion cracking are used to determine strike and damage probabilities.

Each Low pressure turbine consists of a double flow rotor assembly'n outer cylinderi two inner cylindersi and blade rings.

The rotor assembly consists of a shaft with ten shrunk-on discs made of Low aLLoy steel and two shrunk-on couplings.

Missiles from disgs and blade ring fragments are assumed to occur in either 90 or 120 segments.

The geometry'eights~

and exit velocities of the postulated missiles are provided by Westinghousei for both 90 and 120 segments at 0

0 rated speedr 20% overspeedi and destructive overspeed conditions.

In the strike and damage probability assessmenti the destructive overspeed condition is not considered because of the reliability of the turbine overspeed protection system>

described in 3.5 '.3.5 and 10.2.

St'rike and damage probabilities for the 20% overspeed condition were calculated'nd shown to be substantially Less than strike and damage probabilities at the rated speed conditionr due to the significantly Lower missile generation probabilities at 20%

overspeed.

Calculated turbine missile damage probability for the WNP 2 plant is therefore based only on the rated speed conditioni since this introduces no significant error and simplifies the computation.

Strike and damage probabilities for both the 90 segments and 120 segments were calculated' 0

for both horizontaL and vertical targets.

It was shown that strike and damage probabilities are maximized using 90 segments for verticaL targets and 120 segments for horizontal targets.

This is because the horizontaL targets at WNP-2 are more Likely to be hitr up to a pointi by Lower velocity missiles~

and the 120

" segments have Lower exit velocities than the 90 segments.

0 0

This assumption was therefore incorporated into the analysis for conservatismi and to simplify the computation.

3.5.1.3.4 Strike and Damage Probability A probabiListic approach is adopted in order to assess the possibility of damage to systems required for safe shutdown or of accidents which could result in potential offsite 3.5-14

1 Sec'.gZ /(1-2 Sin t e ((tan t -~2z.

Sec t )

2 2

tan<.q ~

2 Sin Cos

~

tan g

-~2z 2

/1-2 z

2 ',2

.Sec 4

2 V

5V.=

D~Y.

Cos R

Where:

vertical component of the ejection angle horizontal component of the ejection angle tvariation in

~ I R.'

~

X, variation in horizontal distance from turbine disc to target element distance from turbine centerline to target element v

= missile exit velocity g

= acceleration of gravity z

= elevation of target element centerline L5 z

= height of target element (vertical: targets)

Q Y

= width of target element (horizontal or verticaL targets)

Q x

= Length of target element (horizonta

-1 X

tan tan iI ~-

R L.. targets)

The probability distributions for both the horizontal and verticaL components of the ejection angle are assumed to be uniform over the range of possible values.

For the horizontal 3.S-14c

0 h

l

WNP-2 the inspection interval during which it is assumed a crack initiates and propogates.

Energy absorption techniques are used to evaluate whether a given disc or fragment is contained within the turbine casing upon rupturei or if it penetratesi what the exit velocity is.

3.5.1.3.4.2 Strike ProbabiLity (P2)

The target areas are divided into target elements.

For targets within the range of the postulated turbine missile there are two possible trajectories to the midpoint of each target element -

a high trajectory and a

Low trajectory.

Even though Regulatory. Guide 1.115 states that high-trajectory turbine missiles may be 'neglectedr they are inc luded in the strike and damage probability calculation for MNP-2 since they were found to contribute significantly to the final result.

For a given missile velocityr as provided by Westinghouse in Reference 3.5-22 for each disc and blade ring fragments the horizontal and verticaL components of the ejection angle are computed for each tra jectory.

Because the target elements are 2dimensionalr there can be some variation in the horizontal and verticaL components of the ejection angle.

These variations can be expressed in terms of the dimensions of the target eLements.

Both the components of the ejection angle and their variations can then be expressed in terms of known missile and target element parametersr as follows:

Vertical Tar ets

(-.-.

(-:;

(-:;)'- (

~-,')~-))

"1 2

2;

-X tan X

Cos R

g Rg R

g Cos f X2 R

Horizontal Tar ets (same as for vertical targets)

(same as for verticaL targets)

3. 5-14b

WNP-2

. components the assumed range is from +5 to -5 measured from 0

0 the perpendicular to the turbine axis for interior discs and blade ring fragmentsr and from +5 to +25 i or -5 to -25 for the end discs and fragments on each low pressure turbine.

For the vertical component of the ejection anglei the assumed range is 120 for a 120 segments and 90 for a

90 segment (i ~ e.i uniform probability distribution over a fuLL 360 of arcr for each of three 120 segmentsr or each of four 90 segmentsr per disc).

The strike probabiLity for target element and missile j is:

~ ij

= ( (c).ac- (~).hvj,.

+ [P(tI ) 5$

~ P(g). Qy~] high tra jectory where:

p(c)

=

p(e)

=

probability of gr per unit angle probability of gr per unit angLe The overaLL str P1

~ P2

= 1 ike proba NiN

'jr i=1rj=1 bility for N missiles and N targets is:

(1-Pl..P2..)

J ij Since Pl.

~ P2..

13 N

P1

~ P2

=

E 1-3 is smally the above expression can be approximated by:

M E

P1.

~ P2..

3 "3

3.5.1.3.4.3 Damage Proba'bility (P3)

For reinforced concrete targets housing safety-related equipmentr the damage prob'ability is conservatively assumed to be 1

i f backface scabbing or spa lling occurs.

This is conservative because concrete fragments wilL not necessaril.y strike safety-related componentsr nor have sufficient energy to disable safety-related components they may happen to striker and redundancy in components and systems wilL normaLLy ensure safe shutdown even if a struck component were to be disabled.

In addition~

in this analysis the worst possible orientation of the missile upon impact with the target is cons'ervatively assumed.

If backface scabbing does not occurs P3 is assumed to be 0.

Backface scabbing 3.5-14d

WNP "2 is calculated to occur using the modified NDRC formula (Reference 3.5-25).

For some target elements the postulated missiLe must pass through a reinforced concrete barrier before, it strikes a target element.

For such missile/barrier inter-actions the modified NDRC formula is used to caLculate whether or not perforation occurs'nd if soi the residual velocity of the missile using the formula:

~ Vr

=

(V,. -V

)'here:

V

= residuaL missile velocity after perforation r

V.

= inc ident missile velocity 1

V

= incident missile velocity required to just perforate the barrieri ca lcuLated using the modi fi ed NDRC formula Any turbine missile striking the Northwest corner of the reactor building refueling floor is assumed to Land directly in or bounce into the spent fuel pool.

This is unacceptable from the standpoint of damage to stored fuel and resulting radiologic releasei so P3 is assumed to be 1 for any such strike.

The overaLL damage probability for N postulated missiles and N target elements is then calculated by:

N N

P4

=

P1

~ P2

~ P3

=

Z Z

P1.

~ P2..

~ P3..

j-1 3

i) i3" This computation is carried out by computers and the resultsr i.e.i damage probability as a function of inservice inspection interval (quantified in terms of turbine operating time)r are shown on Figure 3.5"53.

Inservice inspections for crack detection and monitoring of crack propogation wiLL be performed during refueling outages at a frequency corresponding to an acceptably Low turbine missile damage probability ori a lter-nativelyr at a frequency corresponding to an upper Limit on postulated crack depths using fracture mechanics methodology to postulate crack growth rates and critical crack size.

Inspection frequency will be established following NRC review of Westinghouse topicaL reports on this matters prepared on behalf of the Westinghouse Turbine Owners'roup.

3.5-14e

Og

c.

The geometric strike probability, P2, is a-significant factor.

Several parameter can significantly lower this strike prob ility.

The worst case which can be expect is as arge as P2 = 10 1

(Reference

3. -7).

1)

P2 will be reduced when e turbine discs re not directly align to safety related c mponents.

If the gle of incidence, a,

is reater than 10o~between the plane of t e disc and t 4 structure or component, the p obability f strike is reduced to at lea 10 2)

The targe ize (e.g., fuel pool, RHR heat exchanger adwaste and control room, diesel ener tors, cable spreading room) is in uentia in quantifying P2.

By definition, the ratio of the total target arch, to the over ll postulated missile impact

&ea determines P

(Reference 3.5-7).

Based on destructive overspeed values or Pl = 1.7 x 10 r

-6 P2 = 10 1

(wo st case),

and P3

= 1, the total cumulative prob-ability, P4 is approximately 10 7.

This approach represents a conserva ive lower bound for the probabi 'ty of damage to safet related systems subjected to postu ted high traject; ry missiles.

As such, high trajectory

'ssiles do not constitute a hazard.

3.5.1.3.5 Turbine Overspeed Protection System A single failure in the overspeed sensing and turbine trip systems will not prevent overspeed protection from operating.

The turbine generator is equipped with a digital electo-hydraulic control system.

The turbine control system includes steam admission valves, emergency stop valves, crossover intercept valves, and initial pressure regulator.

Further description of existing systems are available in 10.2.

3.5-15

1

WNP-2 AMENDMENT NO.

14 April 1981 Regulator Guide 1.14, Rev.

1, "Reactor Coolant Pump Flvwheel Integrity", Auqust 1975.

Miller, D.

R.

and Williams, W. A., Tornado Protection for the Spent Fuel Pool, General Electric Comoanv, APED-5696, November 1968.

"Protection Against Pipe Breaks Outside Containment",

Burns and Roe, Inc., Hempstead, New York, Report No.

WPPSS-74-2-R3, April, 1974.

"A Review of Procedures for the Analysis and Desi n

of Concrete Structures to Resist Missile Im act Effects" R.P.

Kennedy, Nuclear and Systems Sciences

Group, Holmes and Narver, Inc., September 1975.

"Anal sis of the Probabilit of the Generation and Strike of Mxssxles from a Nuclear" Turbine" March, 197 by Westznqhouse Electric Corporation Steam Turbine Division Engineering.

NUREG-75/087, USNRC Standard Review Plan, Section

3. 5. 1. 6, November 1975.

Oldfield, G. V., WPPSS, personal communication with Lou Rosgen, Control Tower Chief, Tri-Cities Airport, Federal Aviation Administration, January 14, 1980.

Oldfield, G. V., WPPSS, personal communication with Bill Granston, Area Specialist, Seattle Air Route Traffic Control Center, Federal Aviation Administration, January 15, 1980.

Seattle Sectional Aeronautical Chart, 18th Edition, U.S. Department of Commerce, NOAA, Washinqton, D. C.,

January 24, 1980.

"List of Accidents Showinq Impact Severity and Anqle in Third Display, U.

S. Civil Aviation, 1978",

National Transportation Safety Board, Washington, D.C.

3.5-27

I

~

)t

Insert 1

3.5-21 3.5-22 ta Page 3.5-27:

"Methodo ogy for Calculating the ProbabiLity of a

Missile Generation from Rupture of a

Low Pressure Turbine jDisc" i Westinghouse El ec t ri c Corpo rat i one CT-24076 r Re v i s i on 1i Jul y 1980.

"Turbine Missi Le Report (HP296-LP281-LP281-LP-281) "i Westinghouse ELectric Corporationr CT-24869r Revision Or De c e mbe r 1980.

3.5-23 "Turbine Missile Reports Results of Probability Analysis of Disc Rupture,and Missile Generation"r Westinghouse ELectric Corporations CT-24870'evision 1r March 1981.

3.5-24 3.5-25

" Cracking in Low Pressure Turbine Discs"r IE Information Notice No. 79-37'etter from R.

H. Engelkeni NRCr to N. 0. Strands Washington Public Power Supply Systems dated December 28'979~

"Structural Analysis and Design of Nuclear Plant Facilities" i Chapter 6 (Design Against Impulse and Impact Loads) r ASCE Manuals and Reports on Engineer-ing Practice No. 58'980.

WNP-2 AMENDMENT NO 9

April 1980 TABLE 3'-3 LOW PRESSURE TURBINE MISSILE CHARACTERISTICS 277 DISC 1

DISC 2

449 Djsc 3

548 DISC 4

3683 DISC This Disc A2(ft )

L(ft)

2. 64 DISC 1

. 5.39 DISC 2

4.77 DISC 3

2.00 F 00 DISC 4

2.40 5.

0 DISC 5

5.1 A).

A2:

A3:

EXIT ENERGY (FT-LB)

LARGEST FRAGMENT WEIGHT(LB' EXIT VELOCITY (FT/SEC)

LEAVING HOUSING (106) 3521

'4. 2 3611 564 7.7. 8 2741 8.6 2747 12.8 5

53 24.4 Table shows the over-all width an projected impact areas of any QUadrant.

/

H A) (ft )

A3(ft )

W(ft) 2.78'3.63 6.08 2.55

,/

3.28 6.08 2.72 V'.74'.30

2. 80

/

1.96 3.60 2.70 3.03

/' '2 4.00 2.33 DISC RIM PROJECTED IMPACT AREA

/

DISC END PROJECTED IMPACT AREA

/

DISC HUB /PROJECTED IMPACT AREA W:

MAX DIMENSION OF DISC QUADRANT L:

RADZAL DIMENSION OF DISC QUADRANT WESTINGHOUSE g

1975 REFER TO FIGURE 3.5-35 cl~r/

3.5-30

TABLE 3.5-4

/

MINIMUMVALUES OF WALL THICKNESSES COMPONEN MISSILE WALLS SLABS

, OTHER TOTAL IN FEET PRESSURE VESSEL LTM 6 ASSOCIATED DRYhELL PIPING HTM RHR HEAT EXCHANGER5 LTM ATM HTM FUEL POOL 2'-3"+4+5 2 I 3II 1.5 0

0 0

0 8

'eactor PiPing 6

3 I gll 1.5 RADWASTE BUILDING LTM 3.5+2 5 I SPI HTM 2.5-6 CONTROL LTM i 3'+

ROOM STANDBY HTM PUMP ROOMS

/

Note:

LTM'denotes.low trajectory missile and HTM denotes high trajectory missile 2.5-6 5.5

3. 5-31

REACTOR 5LDG.

H. P.

TUR5tH%.

/v TOP OF CONCRETE T', ~

EL.524

.531 (sza F)G. 3.5&)

L.P.

TURS LHR 3-6

~ o</

2B',~:: ~l ~,

Q&

T.O.C.

EL,531 p

g b g d7 T,O.C.

E.Say'.O.C.

KL.531 OPERATlNS FLOOR, PLA'N 4'7 Kl., 50l" 0 WASHINGTON PUBLIC POWER SUPPLY SYSTEM NUCLEAR PROJECT NO.

2

~<Pg1Vg C ~S+ra" PL ~4~

~~a Ogl.C~r+Ti~ ~ )

~II&%8E4TGIR~~ES

~~M45TMPK&RH<WR-EWPEE-ZMC-OERGN-S894-FIGURE

3. 5-33

~

~ (

~ t 4

~ ~

I I

'fR ApICQT PJ'S(pl~t

~EL. 604-Id'.

TURB 1 RES EI.54.8'- OU I

v EL. 501-0 REACTOR BLDG WASIIINGTOIIPUBLIC POWER SUPPLY SYSTEH NUCLEAR PROJECT IIO. 2 Tui.'.I;r.VI, Wl~~i~C rA)'-:I.=T Lc<..'TA-':

F-u I-'.r:i~Mc~tr

~ZURBiII&RVAltE'O'ARRTERS FIGURE 3.5-34

WASHINGTON PUBLIC POWER SUPPLY SYSTEM NUCLEAR PROJECT NO.

2 CHARACTERISTICS OF TURBINE GENERATOR MISSILES FIGURE 3.5-35

1

44 I

I Io 5

~

fl C5AVlhCE Plo BABILI)f (Pq)

PER

YEAR, (0

5 5

I to (0

(0

-8 (0

Ir45PK~TION IPl TEIIVhL OPKRhTIHG TINE) 3 +~5'g to FIcuRE (ms