ML19208D555

Forwards Revision 2 to Rept 36A59, Fnp Core Ladle Design & Safety Evaluation. Revision Reflects Sandia Lab Comments Transmitted in NRC 790605 Ltr & Results of 790724 Meeting W/Nrc & Sandia Lab

ML19208D555
Person / Time
Site:	Atlantic Nuclear Power Plant
Issue date:	09/21/1979
From:	Haga P OFFSHORE POWER SYSTEMS (SUBS. OF WESTINGHOUSE ELECTRI
To:	Baer R Office of Nuclear Reactor Regulation
References
FNP-PAL-052, FNP-PAL-52, NUDOCS 7909280607
Download: ML19208D555 (30)

Text

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FNP-PAL-052 Offshoro Power Systems ,

September 21, 1979 Mr. Robert L. Baer, Chief Light Water Reactors Branch No. 2 Division of Project Management U.S. Nuclear Regulatory Conmission 7920 Norfolk Avenue Bethesda, Maryland 20852 A B. Ha<a Re: Docket No. STN 50-437; Revision 2 to OPS Report 36A59

Dear Mr. Baer:

Transmitted herewith are seventy (70) copies of Revision 2 to Offshore Power Systems Topical Report 36A59, "FNP Core Ladle Design and Safety Evaluation". This revision responds to the comme'its of Sandia Laboratories transmitted by your letter of June 5, 1979. The content of Revision 2 also reflects the discussions which took place in a meeting between Offshore Power Systems, the NRC Staff and Sandia personnel on July 24, 1979.

Ver truly y urs, P. B. Hag

/lel CC: V. W. Campbell P. B. Haga Attachment 1053 223 790928 0bs 7

Offshore Power Systems Responses to ACRS Letter Dated July 25, 1979 ERRATA

p. 4 Charge " fire" to " fibre" in line 12.

p. 7 Change " critique of" to " critique (Reference 15) of" in line 12.

p. 10 Change " Figures 9 and 10" to " Figures 12 aryJ 13" in line 17.

p. 11 Change " Figure 10" to " Figure 13" in line 2.

p. 13 ASS "(Reference 9)" to the erd of line 3 of the response.

p. 16 Replace with new page.

p. 23 Change "ZrO anchor br icks" to "ZrO ." in line 13 of the 2 2 response

p. 27 Change "1700 C" to "1690 C" in line 10 of the response.

p. 30 Charge "of - quartz to - quartz" to "of - cuartz to quartz" in line 21.

p. 40 Change "subcritical." to "subcritical ard cooled." in line 8.

p. 41 Charge "SG Ca partment" to " Safeguards Cmpar tment" at the bottom of the page.

p. 50 Change " indirect" to "inadvertant" in line 22.

p. 54 Replace with new page,

p. 56 Change "or" to "on" in line 8.

p. 60 Change "Further , the containment. . ." to "Further 5 it was shown in the LPGS that the contairinent. . .' in line 7 of the response,

p. 63 Change "refarence (12)" to " reference (17)" in line 6 of the response.

p. 66 Change " comments on FES-III" w " comments on the Revised Draf t FES-III" in line 6 of the response.

p. 67 Change 30A59 to 36A59 in Reference 2.

p. 68 Charge "6130178" to "6/30/78" in the last line.

p. 70 Replace with new page,

p. 72 Delete asterisks (*) from the FNP colunn (in three places) .

p. 72 Change " flow" to " floor" in the second line of note (1) .

p. 76 Change item 3 to read "3. SPACE OVER SAFDGUARDS".

Figure 16 Replace with new sheet. 1053 224 Figure 19 Replace with new sheet.

Question a.3. (b)

Discuss the consequences of Item 2 with respect to loss of hear th capacity.

Response

The ladle volume was originally established as 980 cubic feet based on core melt constitutents given in Table IV-1 of Reference 2. Ongoirg evaluations have shown that a substantial fraction of the reactor vessel and internals may melt durirg the debris retention period. Table 2 lists the total weight and estimated (molten) volume of steel in the reactor vessel and appurtenances. The ladle volume of approximately 40C0 cu ft is adequate to contain the entire fuel assembly voltme plus 93% of the total available volume of additional materials listed in Table 2.

The new ladle configuration has been developed within the existing constraints of the reactor cavity steel structure by altering the bend radius of the incore instr umentation from a 12 to an 8 foot radius.

Offshore Power Systems believes the change in configuration of the ladle within the major constraints of the existing rip design demonstrates considerable latitude and flexibility to respord to changes that may be dictated in the more detailed design phase.

1053 225 9

schedule and the 10 operating ships were retrofitted during the first refuelirg activity, all within the existing hull and compartmentation envelope. Further, the change in mission objectives for the Fleet Ballistic Missile Program resulted in approximately 30 subnarines being subjected to major retrofits during conversion from the Polaris to the Poseidon missile launch capability. Finally, the Ship Life Extension Program (SIEP) present-ly underway by the Navy to overha.J the Forrestal Class Aircraft Carrier is a very extensive retrofitting program to extend the service life of the ship from 25 to 35 years. The estimated cost (approximately 500 million dollars per ship) illustrates the maanittx3e of changes which can be accomp-lished on such vessels.

The above examples provide assurance that the ENP can be retrofitted to accomnodate changes without degrading the safety or operability of the plant. When comparing the ratio of equipnent and distributive system density between the FNP and canplex marine vessels, Navy vessels in particular, it is felt that the arrangement of the EWP and the segregation and separation of systems afford a high probability that needed design changes can be accomplished to satisfy future requirements.

1053 226 TABLE 2 REACTOR VESSEL AND INTERNALS WEIGHT AND VODUME 3

Source Weight (lbs) Volume (ft ),

Reactor Vessel 700,920** 1752 Reactor Vessel Head 159,500 399 Studs, Nuts, Washers, etc. 45,100 113 Lower Internals 252,000** 630 Upper Internals 153,000 382 Bottom Mounted In-Core Instr. 12,000 30 CRDM's 74,000 185 R.V. Insulation 1,000 3 U.H.I. Piping 8,300 21 Lifting Rig & Seismic Support 72,000 180 TOTAL 1,477,820 3695

• Steel density of 400 #/ft is assumed.

• • Includes the steel listed in Table IV-1 of Report 36A59, reference (2) .

1053 227

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" Phase Diagrams for Ceramists," The American Ceramic Society, Columbus, Ohio, 1964 1053 228 Figure 16 Mg0-SiO2 Phase Diagram

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Instructions for Entering Revision 1 in OPS Report 36A59

1. Replace the Table of Contents page.

2. Replace pages V-1 through V-16 with new pages V-1 through V-21.

1053 230

TABLE OF CONTENIS I. INTRODUCTION II. DESIGN CONSTRAINIS AND FUNCTIONAL DESIGN REQUIREMENTS III. DESIGN DESCRIPTICN IV. DESIGN EVALUATIONS AND ANALYSIS V. TESTItG PROGRN1 FOR CONFIR4ING ADEQUACY OF LADLE DESIGN VI. ASSOCIATED SITE CRITERIA VII. IMPACT OF IADLE DESIGN ON DOSE CONSEQUENCES VIA LIQUID PATETCsYS VIII. REFERENCES APPENDIX A (DRE MELT PENSTRATION APPENDIX B RADIATIW ANALYSIS APPENDIX C TECHNICAL DATA AND SUPPLEMENTAL INFORMATION APPENDIX D RELATED INDUSTRIAL EXPERIENCE APPENDIX E COST ESTIMATE APPENDIX F ADDITIONAL INEDRMATION REQUESTED BY NRC Drir .G MAY 7-8, 1979 MEETINGS 1053 231 Rev. 2

-i-

V. 'IESTING PROGRAM FOR CONFIRMING ADEQUACY OF LADLE DESIGN V.A Purpose The purposes of the testing program for confirming the aSequacy of the ladle design are:

1. Obtain otherwise unavailable data required to confirm that the core ladle will meet its functional design requirments listed in Section II.

2. Obtain otherwise unavailable data required to confirm that the core ladle does not cmprmise existirg safety.

V.B General The refractory ladle is being incorporated in the FNP to assist in reducing envirorTnental consequences of a postulated core-melt accident. The ladle is intended to provide a sufficient delay in the time of core melt-through so that effective interdictive action can be instituted to reduce the environmental consequences of such an accident. Because the ladle is not required by the NBC for public health ard safety, confirmation of ladle design will be based on realistic rather than highly conservative assump-tions, analyses ard tests. This is the approach consistantly taken by NRC for the evaluation of environmental consequences and risk.

Rev. 2 b [ S (. a[

V-1

V.C Approach l Offshore Power Systems will provide, for evaluation by NRC, the information needed to establish that the core ladle can perform its intended environ-mental protection function and that the core ladle does not compromise existing FNP safety functions and capabilities. At least three sources can be utilized to obtain the needed information:

1. Applicable experience and technology frm the metals refinirg in-dustry,

2. Test programs sponsored by NRC, DOE or other sources which are planned or alrea3y in progress relataxl to high tmperatures inter-actions between molten oxides and refractory matericls,

3. A specific core ladle testing progran funded by OPS.

O The first two sources listed above will be relied on to the extent possible by OPS in assemblirg the data required to establish the adequacy of the ladle design and in determining the extent of additional ladle qualifica-tions testirg to be performed by OPS. Table V-1 identifies the OPS core ladle testing program as it is currently conceived. As detailed design proceeds an3 as additional information becmes available frm related testing programs sponsored by NRC, DOS, or other sources, modifications to the core ladle testirg progran may be appropriate and if so they will be maSe after discussion with NBC. In a3dition, test program results may indicate that certain design concepts or design features are not suitable

. ~ ,

O 3i 3 I Rev. 2 V-2 1053 233

for meeting the core ladle functional requirements. If such proves to be the case, uppropriate design alterations and additional testing (if needed) will be proposed.

V.D Schedule and Cost It is Offshore Power Systems' intent to initiate a testing program after an FNP custmer is identified.

As indicated in the Table V-1, it is estimated that the testing program can be empleted in about 18 months. Offshore Power Systens estimates that it would take about six months to initiate the testing program. At the conclusion of the testing pro;,2n, the pertinent data would be suamarized, evaluated and the evaluationc- subnitted to NRC for their review. Six months is estimated for NRC review and evaluation. The estimated 2-1/2 years from initiation of the testing program to empletion of NRC review coincides with the period between custmer identification ard the need to begin manufacture of major elements of the FNP hull as projected by Offshore Power Systems.

Total estimated cost of the testing program is about $700,000.

V.E Summary of Information Needs and Core Ladle Testing Program In this section potential information needs in the following four areas are evaluated ard discussed:

1053 234 b [ f Rev. 2 V-3

1. Physical ard chenical interaction between melt debris ard the MgO ladle

2. Physical behavior of the MgO ladle

3. Thermal interaction between the ladle and molten core debris.

4. Safety related concerns The OPS testing program for confirming the a3equacy of the ladle design is sumarized in Table V-1.

1. Physical and chemical interaction between melt dela .s and the MgO bed

a. Eutectic formation for the MgO, U0 ,2 ZrO , 2FeO multicomponent system

i. Description For current penetration calc:? ations, penetration of MgO is assuned to be a uniform physical melting process which occurs at the temperature of UO 2-MgO eutectic.

ii. Importance to Ladle The rate at which nolten core debris erodes or penc ; rates into MgO is a basic parameter in determining the le>gth of time which a ladle constructed of MgO can delay core debris melt through. If the interaction process occurs at a O

i V-4 Rev. 2 1053 235

significantly lower temperature than that of the bg0-U0 2 eutectic, the rate of bed attack may be increased slightly.

iii. State of Knowledge Phase diagrams are available for Fe O -M O -Mgo 23 2 systems which indicate miscibility of the molten oxides at high temperatures. Phase diagrams for both UO 2-Mgo and Fe O -by0 show eutectics with melting points substantially 23 lower than that of b%o. Formation of a eutectic with an even lower melting point (than UO -Mgo) when Coritm in-2 teracts with Mgo may be possible.

iv. Information Required Test data may be needed to insure that lower melting points eutectics do not form for the Corium-Mgo system.

b. Effect of Fyo Impurities on Grain Boundary Attack

i. Description Preferential attack of Mg0 along grain boundaries could produce a higher rate of attack of the Mgo by causing erosion of the surface rather than bulk dissolution.

Impurities precipitated at the grain boundaries are known to increase the terdency for grain boundary erosion attack.

1053 236 s , .

i r

V-5

ii. Importance to Ladle Preferential grain boundary attack could increase the rate of Mgo loss ard decrease ladle retention time.

iii. State of Knowledge There are some test results that show penetration of Mgo grain boundaries by molten 002 . We know of no specific data on the effect of impurities in the Mg0 on grain boundary attack.

iv. Information Required Tests are needed to determine the importance of impurities in Mg0 on the rate of attack of Mgo by molten oxides present in Corium.

c. Enhanced Err sion at Temperatures Below Eutectic Temperatures O

i. Description Erosion or mechanical removal of solid Mgo from the ladle surface at ta peratures below the eutectic taperature could increase the rate of lalle attack.

ii. Importance to Ladle Enhanced erosion at temperatures below the eutectic temper-ature could increase the rate of Mgo loss ard decrease ladle retention time.

. . O Rev. 2 V-6 1053 237

iii. State of Knowledge Little data exist for temperatures above 2000 C and below the M30-tD2 eutectic ta perature, iv. Information Required One or two medium scale tests are required to confirm that erosion does not lead to enhanced attack at these tmpera-tures,

d. Slag Line Attack

i. Description See Section IV.E for the description and state of knowledge on this subject.

ii. Imirrtance to Ladle If a substantial layer of iron oxide (slag) were to thrm on top of the molten debris in the ladle ard if e.;Lensive attack at the slag line were to occur, preferential lateral dissolution of the ladle at the slag line could occur theceby reducing melt-through delay times.

iii. Information Required Available information indicates that slag line attack rates are low in steel making furnaces. Additional confirmatory g ,( , testing with the mixed oxides present in Corium is re-

+

_t ( l quired.

1053 238 Rev. 2

e. High temperature chemical interaction between melt debris and ladle

i. Description If an exothermic chemical interaction between melt debris ard Mgo were to occur at high temperatures, the additional energy source could lead to an enhanced rate of la31e attack, ii. Importance to Ladle An increase rate of ladle attack could reduce ladle melt-through times, iii. State of Knowledge While chemical interactions at temperatures above 2000 C are not expected, definite data are not presently available.

iv. Information Required Small scale high temperature tests are required to confirm that chemical interactions do not lead to an enhanced rate of attack.

1053239g c .

V-8

2. Physical Behavior of MgO Ladle

a. Floatup

i. Description

'Ihe refractory ladle described in Section III is con-structed of fixed Mgo bricks with a density less than half of that of molten debris. If the molten debris penetrates arourd the bricks and if the bricks are not restrained, they will float on the denser molten debris.

/

ii. Importance to Ladle Extensive floatup could lead to relatively rapid penetra-tion of the refractory ladle thereby shortening the melt delay time.

iii. State of Knowledge Floatup has rarely been experienced in the refractory-lined furnaces and ladles used in the metals refinire industry.

Like Corium, steel melts are also more dense than the MgO refractories used to contain then. In addition, floatup has not been observed in furnaces used for refining nickel melts whose densities are as high as those of Corium. In the metals refining industries, the refractory linings of furnaces aM ladles are usually constructed in an inverted arch shape so that the arch wedging action reduces floatup

\ ;- '

teMency.

1053 240 V-9 Rev. 2

iv. Additional Information Required

'Ihe ENP refractory ladle will be constructed in an inverted arch configuration similar to those normally sployed for refractory linings in furnaces and ladles in the me' als refining industry. In addition, a tongue aM groove brick configuration with staggered layers is planned to further restrict the terdency for floatup. Based on experience in the metals refining industry and the design features incorporated in the ladle to prevent floatup, this subject is considered to be adequately treated and no testing is required.

b. termal Shock and Spalling

i. Description When molten materials at high temperature are poured on refractories at roan tenperature, large taperatures gra3i-ents and thermal stresses are induced. 'Ihe thermal stresses can lead to crackirg and/or spalling.

ii. Importance to Ladle Fracturing of the brick as a result of thermal shock can reduce the penetration time of the refractory ladle.

b kh V-10

4 iii. State of Knowledge In the metals refining industry, melts at high *emperatures are poured into furnaces, mixers or ladles that are sme-times cold. Extensive cracking or spalling of refractory lining, which is similar to or more susceptible to thermal shock t. an high purity magnesite brick, does not occur.

Reported results on snall scale tests of molten UO in-2 teractions with high purity magnesite brick are that

" essentially no cracking or spallation was observed",

iv. Information Required An upper layer of chemically bonded MgO brick which is highly resistant to thermal shock will be used in the Fr@.

Experience with refractories in the metale refining industry and existing experimental data provide an adequate basis relative to this subject and no further testing is necessary.

c. Mechanical Shock

i. Description As part of the melt-down process, it is possible for large pieces of debris to fall upon the refractory ladle which may fracture brick.

( i h' <  ! 1053 242 V-ll Rev. 2

ii. Importance to Ladle Fracturing of the brick as a result of physical shock could reduce the penetration time of the refractory ladle.

iii. State of Knowledge In the metals refining industry, heavy objects are dropped onto refractory beds of furnaces with impacts equal to or greater than those which could be produced in a core melt accident (see Appendix D) . Resulting damage to the re-fractory matetial is not such that it impairs its func-tional capability.

iv. Information Needs Experience with refractories in the metals refining in-dustry along with appropriate analysis provides adequate information relative to this subject.

d. Crack Penetration by Melt

i. Description As MgO is heated it expands. A crack may be left between bricks to accortmodate brick expansion during heatup (see Section IV) . A small gap may continue to exist between sane bricks as a result of loss than perfect construction or as a result of non-uniform temperatures across the bed.

Thus penetration of cracks between bricks by molten debris may occur.

1053 243 O V-12 Rev. 2

ii. Importance to Ladle Extensive crack penetration could lead to brick floatup and enhanced bed penetration, iii. State of Knowledge Freezing of the debris melt as it flows into the narrow cracks between bricks is likely to limit crack penetration.

Experience from the metals refining industry iMicates crack penetration is not a problem although the range of temperatures associated with such application is not as great as may be experienced for a molten core debris ladle.

Calculations indicate that the maximun penetration of the core ladle would be about one layer of brick.

iv. Information Required The extent of crack penetration for a range of crack sizes and tenperature needs to be exanined.

3. Thermal Interactions Between Ladle and Molten Debris

a. Fractions of available energy lost to radiant upward heating

i. Description Some fraction of the decay heat energy generated in the molten core debris will be lost to the surfaces surrounSing the pool by thermal radiation. 'Ihis energy will not be available for melting the refractory ladle material.

1053 244 V-13 Rev. 2

ii. Importance to Ladle Calculations indicate an acceptable ladle life for radiant loss fractions as low as 10%.

iii. State of Knowledge Models exist for estimating radiant losses for fixed geo-metries and for known temperatures of the radiating body (pool) and receptor (surfaces above the pool) . There is, however, uncertainty regarding the surface temperature of the pool.

iv. Information Needs Bounding calculations sho'. t;.at a reasonabh thickness of refractory material can provide the necessary delay times for conservative assumptions regarding thermal energy radiation losses. Thus additional information is not needed.

b. Relative Rates of Energy Loss into MgO Ladle Laterally and Vertically

i. Description In current estimates of ladle penetration rates, heat flow per unit area into the 330 fran the molten debris pool is assumed to be equal in the horizontal and vertical direc-tions.

O pl 3 { Rev. 2 1053 245

ii. Importance to Ladle With the assumption of equal lateral and vertical heat flow per unit area, the proposed Mgo ladle is calculated to provide retention of two days in both the lateral and vertical directions (see Section IV.A) . If heat flow per unit area in one direction proves to be substantially greater than the other, a different ladle configuration will be required and can be accomodated within the platform configuration, iii. State of Knowledge Energy flow per unit area in the lateral and vertical direc-tion are assuned to be equal. The basis for this assumption was engineering judgment, iv. Information Needs Information is needed to determine if energy flow per unit area in the lateral an3 vertical directions are approximately the same. Approximate values (+10 to 15%) are adegaate.

4. Safety Related Concerns Safety-related concerns listed under item 4 in Table V-1 are dis-cussed in other sections of this report. Specifically, radiation shielding is discussed in Sxtion IV.3, gas generation by bed ma-terials is discussed in Section IV.C, ar.1 criteria applied to inter-action between the ladle and safety related structures are discussed in Section III.K.

1 ' t f

1053 246 Rev. 2 V-15

There are no ladle testing programs associated with safety-related concerns because a3 equate information currently exists.

V.F. Elements of Planned NRC Test Programs Applicable to FNP Ladle The Nuclear Regulatory Research Program contains a nmber of planned tests which will yield information applicable to the ENP refractory ladle.

Elements of the program were provided to OPS by the Fuel Behavior Research Branch, Division of Reactory Safety Research of NRC, reference (7) . Tests applicable to the ladle have been suamarized in Table V-2. The test series are briefly described in the following sections.

1. Furnace Heat Up Tests A series of tests is planned in which metal and oxide materials will be heated in snall crucibles of candidate core-melt retention mater-ials to temperatures where the metal and oxide mixtures melt. Incltded will be tests with M30 crucibles, iron-iron oxide ard Corium melts.

Initial tests will be at temperatures of about 3100 F. Temperatures up to 4000 F are possible in the furnace. Such tests can be used to derive information on slag line attack, MgO penetration rates by oxides and possibly on phase relationships, particularly eutectic formation.

2. Small Scale Inductive Heating Tests (CATH Series)

In these tests metal-oxide and Coritra melts will be inductively heated in small refractory crucibles (Crucibles are 6" OD by 12" high) .

Included will be tests with MgO crucibles containire iron-iron oxide O

• • • 2 c V-16 m4 1053 247

melts and Corium melts. Also included will be tests with MO crucibles with cracks. These tests will provide information on slag line attack, rate of M30 penetration by various oxide melts, and the extent of penetration of cracks by the oxide melts.

3. Large Scale Tests with Inductive Heating A series of tests in which approximately 440 lbs of steel is heate' to approximately 3100 F and then poured into cruccJes of various refractory material or conctete has been conduc A at Sandia. After pouring, melt tempe'i ature is maintained by inductive heating. The test already conducted with a MgO crucible was of limited usefcIness since inductive heating was lost early in the test. One a3ditional test with a crucible constructed of alunina cenent is planned and another test with a Mgo crucible may be conducted. A test with a MgO crucible could provide information on Mgo penetration rate as well as relative rates of energy flow in the vertical and horizontal directions.

g.,

e i I 1053 248 Rev. 2

9 TABLE V-1

SUMMARY

OF LADLE IN MRMATION NEEDS AND TESTING PROGRAMS .

l I

1. Physical and Chemical Interaction Between Melt Debris and Mg0 Bed Comnents Estimated or Esti-Information Type of Testing mated Needed Test Period Cost

a. Eutectic formation for the 15 to 20 snall scale, 18 months 250,000 Mg0, 00 , Zr0 , Fe0 multi-2 2 sustained heating cmponent system furnace te-ts

b. Effect of Mg0 impurities on 5 to 10 small scale, 6 months 50,000 rate of penetration by sustained heating molten debris furnace tests

c. Potential enhanced attack by 2 meditzn scale tests 6 months 50,000 erosion at temperatures below eutectic tenperatures

d. Potential for slag line 1 medium scale test 3 months 25,000 attack assumirg data from (la) are enployed

e. Potential for rapid attack 2 - 4 snall scale, 15 months 125,000 at high temperatures due to high temperature { l chenical interaction be- tests.

tween melt debris and Mg0

2. Physical Behavior of Mg0 Bed

a. Brick floatup upon contact None Industrial with high density molten sufficient debris to estab-lish there is not a problem

b. Thermal shock with None Industrial spalling of ladle brick experience sufficient with addition of resistant top layer of brick r 1053 249 i i V-18 Rev. 2

TABLE V-1 (CONT'D)

SUMM'mY OF LADLE INFORMATICN NEEDS AND TESTING PROGRAMS

c. Mechanical shock causing None Industrial degradation of bed experience shows this is not a problem

d. Extensive melt penetration 3 small scale, sus- 9 months 50,000 of cracks beteen brick tained heating tests leadirg to breakup of bed

3. Thermal Interaction Between Ladle and Debris

a. Energy loss due to radiant None -

Treated by upward beating by bounding calculations which assume all energy is directed into bed

b. Energy split between the 2 mediun scale high 18 months 150,000 downward and lateral temperature tests directions

4. Safety Related Concerns

a. Radiation shielding proper- None -

Adequate ties of Mg0 cross sec-tion data can be de-rived from existing literature

b. Gas generation capability None -

Bourding gas generation fran top layer of chenically borded brick can be tolerated.

Little if any gas generation from MgG j , ,,.,

. melting.

1053 250 Rev. 2 V-19

TABLE V-1 (CONT'D)

SUMMARY

OF LADLE INFORMATION NEEDS AND TPSTING PROGRAMS

c. Possible effecte of bed % None -

Possible nearby containnent pressure effects can boundary under accident be ade-conditions quately treated analytically based on available information O

ass 251 u

O Res. 2 V-20

TABLE V-2 NBC TEST PROGRAM ELDDTIS APPLICABLE 'IO FNP CORE MELT IADLE TYPE OF TEST TEST MATERIALS APPLICABLE INFORf%TIOt1 Furnace Heat-Up MgO Crucible, Fe-Fe23O Melts Slag Line Attack, MgO Erosion Tests MgO Crucible, Corium-Fe-Fe 23 O Slag Line Attack, MgO Erosion, Melts Phase Relationships Small Scale MgO Crucible, Fe-Fe23O Melt Slag Line Attack, MgO Erosion Inductive Heating CATH-3 Small Scale MgO Crucible with Cracks, Melt Flow In Flaws and Cracks Irductive Fe Melts Heating CATH-4 Small Scale MgO Crucible, Corium Melt MgO Erosion, Slag Line Attack Irductive Hesting CA'IE-6 Small Scale Almina Crucible, Corium Alternate Materials Erosion Inductive Heating Melt Rate ard Susciatibility to CATH-7 Slag Line Attack 200 Kg Steel Melt Almina Csent Crucible, Almina Cment Erosion Rates with Inductive Steel Melt Heatirg (HAC-2)

Incore Test Series Data on Erosion Rates for Various Crucible - Melt Combinations with Internal Melt Heating 1053 252 Rev. 2 V-21