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| {{#Wiki_filter:f REGULATORY I ORHATIGN DISTRIBUTION SYST (RIDS)SUBJECT;Forwards addi jnfo requested by NRC 790109 ltrire analyses of coptaipment temp response to postulated main steam line breaks'ISTRIBUTION CODE: A039S COPIES RECEIVED:LTR i ENCL 9 SIZE: 'L TITLE: Resp to Lesson Learn Task Force 1'Lest jnghouse'END,B | | {{#Wiki_filter:}} |
| ~$'C C.ma7L 7-0 Kv E NOTES,, CAP 8 jYlif 0'C F~RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LtTTR ENCL ID CODE/NAME LTTR ENCL TIONi 10 BC ORB Wl, 7 7 AC INTERNALS 0 05 OLS VSSK.i~07 BURDIO>>i Jo 17 I L E 21 ENG BR 23 PLANT SYS BR 25 EFLT TRT SYS FIEI DSg M~OELD 1 1 1 1 2 2 1 1 1 1 1 1 1 0 02 NRC PDR 06 KERRIGAN J,.08 HILLIS p C, 20 CORE PERF BR 22 REAC SFTY BR 24 EEB ANDERSONeNI O'REILLYgp
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| ~TELFORDgJ,T' 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 ACCESSION NBR:8004080367 DOCeDATE: 80/04/01 NOTARIZED:
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| NO DOCKET FACIL:50 316 Donald C.Cook Nuclear Power Plantr Unit 2i Indiana L 05000316 AUTH~NAMF AUTHOR AFFILIATION MALONEY~G,PE Indiana 8 Michjgan Electric Co.'ECIP~NAME RECIPIENT AFFILIATION DENTON~H.R, Office of Nuclear Reactor Regulation EXTERNAL: 03 LPDR 26 ACRS 1 1 16 04 NSIC 1 1 gC q'7 TOTAL NUMBER OF COPIES REQUIRED: LTTR A5 ENCL IJ INDIANA&MICHIGAN ELECTRIC COMPANY P.O.BOX 18 BOWLING GR E EN STATION NEW YORK, N.Y.10004 April 1, 1980 AEP:NRC:00131
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| 'onald C.Cook Nuclear Plant Unit No.2 Docket No.50-316 License No.DPR-74
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| ==Subject:==
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| Request for Additional Information 022.17 Mr.Harold R.Denton, Director Office of Nuclear Reactor Reg'ulation U.S.Nuclear Regulatory Commission Washington, D.C.20555
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| ==Dear Mr.Denton:==
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| The response to Request for Additional Information 022.17 which was enclosed in Mr.A.Schwencer's letter of January 9, 1979 is contained in the attachment to this letter.Very truly yours, GPM/emc Attachment
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| .P.alon Vice P esid nt cc: R.C.Callen-w/o att.G.Charnoff-w/o att.R.S.Hunter-w/o att.R.W.Jurgensen-w/o att.D.V.Shaller-Bridgman 8004ooo><+,
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| 4*~~~C ,~~E I s,~~j)I!a I"r ATTACHMENT TO AEP:NRC:00131 L
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| ~~ENCLOSURE Re uest for Additional Information Donald C.Cook Nuclear Plant, Unit 2 Docket No.50-316 022.17 We require additional information regarding your analyses of the contai'nment temperature response to postulated main steam line break(s)which you provided in your response to NRC request 022.9.Specifically, we will require the following to complete our review of the containment response to postulated ruptures of the main steam line inside containment.
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| For the worst split break (i.e., 30/power level with assumed failure of the auxiliary feedwater runout protection system), provide the results of containment response analyses using the LOTIC-3 code for a spectrum of break sizes ranging in size up.to the 0.942 ft2 break previously analyzed.The spectrum of breaks analyzed should include the largest split break which would not result in automatic initiation of the containment spray system and the largest split break which would not result in automatic initiation of the containment return air fan(s).For each break analyzed provide: 1)a figure similar to figure 022.9-2 (Appendix g)showing upper and lower compartment tem-perature as a function of time;2)a figure showing containment pressure as a function of time;3)a table similar to Table 022.9-2 (Appendix g)identifying the mass and energy release rate data used in the containment analyses;'and 4)identification of any actions assumed to be performed by a control room operator during the course of the accident and the ,time at which operator actions are assumed to occur including justification for the assumed operator actions.
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| Res onse to 022.17 Rather than performing a plant specific analysis for D.C.Cook Unit 2, a generic i'ce condenser plant small steamline break analysis was performed.
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| It is shown herein that the differences between the generic containment parameters and blowdown releases and the Cook 2 values are either conservative or unimportant.
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| The following evaluation justifies that referencing the generic work for Donald C.Cook is conservative.
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| The LOTIC-3 computer code was employed in the generic analysis.The LOTIC-3 computer code has been developed to analyze steamline breaks in an ice condenser plant.During the development of this computer code, discussion and justification of the heat transfer coefficients and of the thermodynami'c equations have been presented to the NRC.Details of the LOTIC-3 computer code are given in References 1 to 3.The LOTIC-3 computer code has been found to be acceptable for the analysis of steamline breaks (Reference 4)with the following restrictions:
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| a.Mass and energy release rates are calculated with an approved model.b.Complete break spectrums are analyzed.c.Convective heat flux calculations as described in Reference 2, g7, are performed for all'break sizes.NRC question, 022.9 (Reference 6)pertains to the steamline break analysis and its subsequent response in identifying the limiting small break.The following evaluation will illustrate the conservatism in those results and the relative insensitive nature of the containment response to break si'ze.The net containment free volume assumed in the generic analysis was 1,193,971 ft3 while the Cook 2 free volume is 1,241,384 ft3.Further, the generic plant lower compartment was assumed to have a volume of 235,481 ft3 while the free volume of the Cook 2 lower compartment is 254,'000 ft3.Since containment volume is an important parameter in determining the containment environmental response to a steamline break, this comparison illustrates the conservatism of referencing the generic work.The heat sinks in the lower compartment are of primary importance since this compartment is where the break occurs and consequently ex-periences the most severe environment.
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| The heat sinks in the upper and ice condenser compartments are of secondary importance.
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| 1 The areas and volumes for tPe concrete of the generic plant add up to 25670 ft2 and 47808 ft~respectively, compared to 35459 ft2 and 47358 ft3 for D.C.Cook Unit 2.Even though the concrete volume of the generic plant is slightly greater, (less than 1Ã), this is.more than offset by the surface area comparison which, due to the low thermal conductivity of concrete, is of more importance to heat transfer.This comparison therefore reveals a greater concrete heat transfer area and heat removal capability of D.C.Cook, which would result in a lower calculated peak temperature.
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| Likewise, the steel heat sink comparison displays a greater heat transfer area, volume and heat removal ca@ability.
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| The generic plant's parameters are 3955 ft2 and 167 ft~>compared to 40010 ft2 and 580 ft3 for D.C.Cook>2 The heat sinks in the ice condenser are identical for both plant cases.The preceding comparison,illustrates the conservatism of the generic plant'slower compartment heat sinks.I The last comparison of compartment heat sinks is in the upper compartment.
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| The generjc plant's uppers compartment concrete area and volume, are 26123 ft~and 41722 ft~respectively, compared to 60440 ft2-and 105970 ft3 for D C.Cook"2, The steel heat transfer areas and volumes are 41302 ft~and 2034 ft for the generic plant and 32500 ft~and 1524 ft3 for D.C.Cook"2".Although the generic plant does have a greater upper compartment structural heat removal capability due to steel, this is of secondary importance in the analysis-since the ice condenser allows very little steam into the upper com-partment, and the spray system has the capability to cool the upper compartment.
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| Consequently, the upper compartment's environment is not a severe one and has little impact on the analysis.Tables Q22.17-5 and Q22.17-6 are attached listing the volumes, areas, materials and a description of compartments for both the generic and D.C.Cook Unit 2 Plants.Two spray systems exist for comparison.
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| The upper compartment system has little impact on the lower compartment temperature so emphasis will be on the lower compartment, spray system.The generic plant does not employ.a lower compartment spray system , whereas D.C.Cook Unit 2 does contain a lower compartment spray system (900 gpm).Since the spray system of D.C.Cook Unit 2 is much more efficient because of location than that of the generic plant, the reference to generic parameters is conservative with respect to Cook.In conjunction with the above comparisons a further justification and bases for referencing a generic plant analysis for the D.C.Cook Unit 2 analysis is illustrated in Figure Q22.17-5.This figu~e contains a comparison of the limiting small break cases, 0.942 ft , from the Cook 2 and generic plant's previous small break submittals.
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| Figure Q22.17-5 illustrates that the small steamline break temperature transients result in very similar peaks with any differences being incidental to the results.In addition, elevated containment temperatures for Cook last')for a shorter duration in the transient.
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| Further, the contatnment pressure Hi-2 setpoint which provides the actuation si'gnal for the containment spray and fan systems was assumed to be 3.5 psi'g in the generic analysis.The Cook 2 Hi-2 setpoint is 2.9 psi'g.Therefore, the actuation setpoint would have been reached sooner in D.C.Cook 2 and therefore the containment transient would have been mitigated more rapidly.The evaluation presented above, illustrates the conservative comparison between D.C.Cook 2 and the generic plant's heat sinks and plant parameters.
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| Therefore, a generic LOTIC-II'I spectrum of small breaks analysi's is provided for D.C.Cook 2 instead of a plant specifi'c analysis.The generic analysis provides the contain-ment responses for a spectrum of small breaks at the 305 power level wi'th assumed failure of the auxiliary feedwater runout protection system.The analyses studied a spectrum of breaks ranging in size from 0.1 ft2 up to thy break identified as the most severe small split break, 0.942 ft~.The lower bound break size was established in discussi'ons held between the NRC staff and Westinghouse Electric Corporation.
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| It was also referenced in the Sequoyah Nuclear Plant's response to Q5.56A.I'his spectrum included breaks of.0.6, 0.35 and 0.10 ft.'ttached'igures Q22.17-1 and Q22.17-2 provide the upper compartment temperature and lower compartment pressure transients.
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| As Figure Q22.17-3 shows, similar lower compartment temperature transi'ents were calculated for the spectrum of breaks analyzed.However, the 0.6 ft2 break resulted in a sli'ghtly higher maximum lower compartment temperature.(See attached Table Q22.17-1).
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| When this transient was compared to the transient identified as the most severe small break at 30%power in the previous analysi's, i't was found to result in very similar peaks, with the difference being i'ncidental to the results.(See Figure Q22-17.4).
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| In the analysis, spray and fan initiation are automatic after reaching the containment Hi-2 setpoint.Associated times are included in Table Q22.17-1.As described above, these times are conservative in regard to Cook 2.Tables Q22.17-2, Q22.17-3, and Q22.17-4 provide the mass and energy release rates for the transients analyzed.These results demon-strate the conservati'sm of the results previously submitted in response to Q022.9 and also the somewhat'nsensi'tive nature of the ice condenser plant contai'nment response to break size.The comparison illustrated in Figure Q.22 17-5, between a generic plant's temperature transient and the same transient for Cook 2 illustrates the kind of conservatism introduced by referencing the generic analysis.Table Q22.17-7 further demonstrates this conservatism.
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| The actual plant specific analysis results for the smaller breaks would be similar to the Cook 2 results in Figure Q.22.17-5.
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| The temperature would peak, then sharply fall off when the sprays come on, and finally settle to a much lower temperature level for the remainder of the transient.
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| q A V
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| ==References:==
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| 1.C.Eicheldinger, Letter of 10/22/76,¹NS-CE-1250 2.C.Eicheldinger, Letter of 6/14/77,¹NS-CE-1453 3.C.Eicheldinger, Letter of 12/7/77,¹NS-CE-1626 4.John F.Stolz, Letter of 5/3/78,"Evaluation of Proposed Supplement to klCAP-8354 (LOTIC-3)".
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| 5.D.C.Cook, FSAR, Section 14.3.4, Page 30 6.T.M.Anderson, Letter of 9/20/78,¹NS-TNA-1946 t~3OCL'I 0 g 2ocL I~I OO-0.4 f'0 o-3S W 0.<Ft.o.O OoQ 5oo+Q JOOOr 7 IHE'Ec Figure f22.17-1: Upper Compartment Temperature
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| ~(305 8ower'ev~'J)
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| ~.$Q~u
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| =7-4.$0 I I I I o.s5E't~+.o 0)FC 3.o I I Po 0'I 5oo~i~e (sec)-Figure 922.17-2: Lower Compartment Pressure (305 Power Level)
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| Woo'.'sS re 300 n</I l o.l Yt'7 200 5 I Ioo O.O O.C.500 TIE=(Sit')i OOO ,'igure 922.17-3: Lower, Compartment Temperature'305'ower Level)
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| ;%guilt)'L
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| ~~9~'0 3OO'lO ZOO Z l-+o.Q A.P.IhOSg 58vCRQ 5~l.l OHMIC PT QO 4/4 PbuJCR'o.sos fP)1OO 0,0 O.O)OOO 5OQ v>ve (sec)~, Figure (22.17-4: Morst Break Lower Compartment
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| '=Temperature Comparison (Generic Analysis)
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| ,'~~9-<<,~"4 p h L'py$'\ .30P I~P I I yosl SEVERS'RFfK RT Z0%P4L4~(o.~z A.'g As'~'5 o, e wz 4c'oo O.O 5oo mvz (s~c)Figure f22.17-5: Worst Break Lower Compartment I.Temperature Comparison e~pl'IIt'I 4 C
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| -11=abl e (}22."17-1 CASE NAXINUN LC TENP oF TINE t SEC.TINE OF CONTAINNENT*
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| SPRAY FAN 0.6 ft2 326.1 151.39 53.605.0.35 ft2 325.8 322.8 59.617: 0.1 ft2 320.7 651.106.663.*Hi-2 Pressure Setpoint used was 3.5 psig,.Rela'y time used for spray actuation after Hi-2 signal was 45 sec Relay time, used for fan actuation after Hi-2 signal was 600 sec. TIME.1000E-'01
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| .1000E+01.3000 E+01..7000E+01.1400 E+02.2400E+02..2600E+02
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| '2800E+02.3000 E+02.3300E+02.3600E+02.4600E+02.5250E+02.5500E+02.5750E+02.6000E+02 ,.6750 E+02.7000E+02.7500E+02.8500E+02.9500 E+02;1000E+03'.1200 E+03.1400E+03.1800 E+03.2200E+03.2600 E+03.3000E+03.3600E+03.4000E+03.4600E+03.5000E+03.5600 E+03.6400E+03.7000 E+03.7400E%03.8200E+03.8800E+03.9600 E+03.1000E+04.Table f22.17,-2 0.1 FT2 SPLIT'0 PERCENT POWER (lb/sec).2280 E+03.2280 E+03.2260E+03''.2260E+03
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| , 2240 E+03.2220E+03.
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| ~2250E+03.2280E+03.2290E+03.2300E+03.2300 E+03 2290E+03.2280E+03,.2270E+03.2250 E+03'.2220E+03
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| .2150 E+03,.2130E+03..2100E+03.2040E+03.2000E+03.1980E+03.1920 E+03.1870E+03'.1790E+03.1730E+03.1670 E+03.1620E+03.1550 E+03.1500E+03.1440 E+03.1400E+03.1340 E+03.1270E+03'1220E+03.1190 E+03.1130 E+03.1090 E+03.1040 E+03.1020E+03 e (BTU/SEC)~2712 E+06.2712E+06.2688E+06.2688E+06.2665 E+06.2642 E+06..2677=E+06
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| .2711E+06.2722E+06;2734E+06/.2734 E+06.2723E+06.2711E+06.2700E+06'2677E+06.2643 E+06*.2562E+06.2539E+06.2504 E+06.2435 E+06.2388E+06.2365 E+06.2295 E+06.2237E+06.2143 E+06.2073 E+06.2002 E+06.1944E+06.1861 E+06.1802 E+06.1731E+06.1683 E+06.1612 E+06.1528 E+06.1469 E+06.1433E+06.1361E+06.1313 E+06.1253 E+06.1229 E+06 3
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| r~~l-13-TINE'1000E-01.1000E+01.3000E+01.5000E+01..7000E+01.9000E+01~.1000E+02'1300E+02.1500E+02.1600E+02;1900 E+02.2000E+02.2500E+02;3000E+02.3500E+OZ.4000E+02.5000E+OZ.6000E+02.7000E+02.8000E+02.9000E+02.1000E+03.1200E+03.1400E+03.1600E+03.1800EE.03
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| .2000E+03.2400E+03.2800E+03.3200E+03.3600E+03.4000Ee03.5000E+03.6000E+03.7000E+03.8000E+03.9000E+03.1000E+04 Table,(22.17-3
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| 'I T 0~35"TZ SPLIT 30 PERCENT POWER (lb/sec).7970E+03.7970E+03.7890E+03...7820E+03.7760E+03.7700E+03.7680E+03.7760E+03.7800E+03.8960E+03.1240E+04.7720E+03'7090E+03.6630E+03.6280E+03.6010E+03*-.5630E+03;5350E+03.5140E+03.4970E+03.4830E+03.4700E+03.4500E+03.4320E+03.4160E+03.4020E+03.3890E+03,,.3650E+03.3440E+03.3240E+03.3060E+03.2890E+03.2530E+03.2230E+03.1990E+03.1790E+03.1620E+03.1480E+03 e (BTU/SEC)..9480E+06
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| .9480E+06.9388E+06-.9308E+06.7239E+06.9169E+06.9145E+06.9237E+06-9284E+06.1066E+07.1476E+07.9195E+06.8466E+06-7930E+06..7520E+06
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| .7203E+06.6756E+06.6425E+06.6176E+06.5974E+06.5808E+06.5653E+06.5415E+06.5200E+06.5008E+06.4841f+06.4685E+06.4397E+06.4144 E+06-.3904E+06.3687E+06.3481E+06.3046E+06.2683E+06.2392E+06.2150E+06.1944 E+06.1774E<06 TIME.1000E-01.1000E+01.3000&01.5000E+01.7000&61 ,.8000E+01.1000E+02.1200E+02.1300E+02.1400E+02..1600E+02.1800E+02..2000E+02
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| .2200E+02.2400E+02..2700E+02
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| .3200E+02.3600E+02.4000E+02.4600E+02.5000E+02.6000E+02.7500E+OZ.9500E+02.1200E+03.1400E+03.1800E+03.2200E+03.2400E+03.2600E+03.3000E+03.3600E+03.4200E+03.5000E+03.5600E+03;6000E+03.8600E+03.
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| .9600E+03.9800E+03.1000E+04-14-.Table (22,17-4 0.6 FTZ SPLIT 30 PERCENT POWER{lb/sec)..1365E+04.1365E+04.1341E+04.1320E+04.1302E+04.1293E+04.1297E+04.1298E+04.1Z97E+04.1268E+04.1196E+04.1133E+04.1079E+04.1033E+04.9940E+03.9440E+03.8800E+03.8420E+03.8110E+03.7740E+03.7540E+03.7130E+03 6680cq03.6250E+03.5840E+03.5570E+03.5110E+03.4720E+03.4530E+03".4350E+03.4020E+03.3600E+03.3250E+03~.2870E+03.2680E+03.2480E+03.1790E+03.1610E+03.1580E+03.1550E+03 e.(BTU/SEC).1624E+07.1624E+07.1596E+07.1572E+07.1551E+07.1541E+07.1545E+07.1546E+07.1545f+07.1513E+07.1429E+07.1355E+07.1292E+07.1238E+07.1192E+07.1133E+07.1057E+07.1012E+07.9754E+06.9313E+06.9074E+06.8584E+06.8045E+06.7529E+06.7036E+06.6711E+06.6156E+06.5685E~06.5455E+06'5238E+06.4838E+06.4330E+06.3905E+06.3445E+06.3154E>06.2972E+06.2136E+06.1918E+06.1882E+06.1846E+06 I l~<g f'jt"\) Table f22.17-5 GENERIC PLANT ICE CQNOENSER OESIGN PARAMETERS l.VOLUME Reactor Containment Yolume (Net free volume, ft3~Upper Compartment Upper Plenum Ice Condenser.I Lower Plenum.Lower Compartment (Active)670,101 47,000 86,300 24,200 235,481 Lower Compartment (Oead Ended)U Total Containment Yolume Tech Spec Weight of Ice in Condenser, lbs 130,899 1,193,971.
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| 2.45 x 10
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| 'k rl~o ABCS& A.U er Com artment TABLE-g cont)2.STRUCTURAL HEAT SlNKS Area Material and Thickness ftz (ft)1..-Polar Crane Wa11, Containment Shell, and Mi seel 1 aneous Steel Slab 1 Slab 2 Slab 3 2.Refueling Canal and Miscel 1 aneous Concrete Slab 4 8915 31667 720'25443 0.000583 0.01017 0.000583.0.05758 0;00167 0.1670 0.00167 1.511 Paint Carbon Steel Paint Carbon Steel Paint Carbon Steel Paint Concrete Slab 5 B.Lower Compartment 1.Pl atf orms Slab 1 2.Steam Generator Supports.and Reactor Coolant Pump Supports 680 1,375 0.00167 Paint 4.82 Concre.e 0.000583 Pa int 0.007813 Carbon Steel S'lab 2 3.Miscellaneous Concrete Slab 3 2,580 23,300 0.00583 0.0605 0.00167 1.645 Paint Steel Paint Concrete 4..Reactor Cavity-17-TABLE 5 (cont)STRUCTURAL HEAT SINKS Area Material and Thickness (f t2)(f't)Slab 4 5.Base Floor*Slab 5 C.Ice Condenser 1.Ice Baskets 2,370 4,228 0.00167 4.0 0.00167 2.0 Paint Concrete Paint Concrete Slab 1 180,628'.00663 Steel'.Lattice Frames Slab 2 3.Lower Support Fracture Slab 3 4.Ice Condenser Floor 76,650 0.0217 28,670 0.0267 Steel Steel Slab 4 5.Containment Wall panels and Containment Shell 3,336 0.000833 Paint 0.333 Concrete Slab 5 6.Crane Wall Panels and Crane Wall ,Slab 6~19,100 1.0 0.0625 13,055 1.0 1.0 Steel It Insulation Steel Shell Steel Im Insulation Concrete P
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| ~~-18-TabIe f22.17-6 O.C.COOK UNIT 2 ICE CONDENSER DESIGN PARA'!ETERS Reactor Containment YoIume Upper, Compartment Lower Compartment Ice Condenser.Dead Ended Tota1 Vo1ume 798742 ft3 254000 ft3 126940 ft3 61702 ft3 1,241,384 ft3 Tech Spec Weight of ice in Condenser, lbs.2.37 x 18
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| '0'I Wal l" 5'ompartment UC..UC UC LC LC'LC TABLE 6 (cont)STRUCTURAL HEAT SINKS Area Materi al 5880 11970 5069 13660 16730 Pai nt/Concrete Paint/Concrete Pai nt/Concrete Pai nt/Concrete Paint/Concrete 32500 Paint/Steel/Concrete 10090 Paint/Concrete Thickness (f t)0.001/0.0469/2.0 0.001/2.0'.001/1.5 0.001/1.0 0.001/2-0 0.001/1.5 0.001/1.0 8 LC LC 8665 6995 Paint/Concrete Paint/Steel 0.001/2.0 0.001/0.008 10 12 LC LC LC 3340 1170 Paint/Steel S.Steel 23650 Paint/Steel 0.001/0.0096 0.001/0.0419 0.0334 13 LC LC 276 4580 Lead Paint/Steel 0.25 0.001/0.0149 15.16 18 19 IB IB IB-IB IB 180600 Steel 76650 Steel 28670 Steel 3336 19100 Paint/Concrete Insul ation and Steo'1/Concrete 0.0066 0.022 0.0267 0.0008/1.5 1.0/0.0625 20 IB 13060 Insulation and Steel/Concrete 1.0/1.0 Table q22.1?-7 KEY PARAMETERS AFFECTING SPLIT STEN LINE 8REAKS Yar i able Fall Load Steam'Pressure (psia)Values Used in, Yalues for~L'DTIC-3 II 0.C.C OOOO 820 Plant Power (t4vt)Time Delay to Feedline Isolation (sec)Time Delay to Steam Line Isolation (sec).3425 15 3403<9.0<9.0 i Jg 0 P 3 1 ASKg~s'j-~t~.}}
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