ML20246L148
| ML20246L148 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 08/28/1989 |
| From: | William Cahill, Walker R TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| TXX-89635, NUDOCS 8909060257 | |
| Download: ML20246L148 (9) | |
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,-c Log #'TXX-89635'
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.910.3 Ref. #'ASME.B&PV Code e
. August'28, 1989
'I WHIinne J. Cahul, Jr.
j becutuve Vue Prnident
'U. S. Nuclear Regulatory Commission l
4 Attn: Document Control Desk-
' Washington.-D.:C.- 20555
SUBJECT:
COMANCHE. PEAK STEAM ELECTRIC STATION (CPSES)
- DOCKET = NOS. '.50-445 AND 50-446 i
ADVANCE FSAR SUBMITTAL l
FRACTURE TOUGHNESS 0F.THE MAIN STEAM AND FEEDWATER SYSTEM MATERIALS.
l
' Gentlemen:
1 This' letter provides an advance'. copy of a change to be' included in a future _
FSAR amendment. ' This change allows the fracture toughness of the main steam
'and feedwater system materials to be determined by fracture analysis in'11eu of impact-. testing, if-permitted by the design specification. -
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'In oro w to facilitate NRC Staff review of this change, the attachment is.
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-organized ~as follows:
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' 1.
Draft revised FSAR pages, with change portions indicated by a bar in
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. the margin, as they are to appear in a future amendment.
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~2.- A detailed. description / justification for the change..
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A copy of a related SER section.
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A page containing the title of a " bullet" which consolidates and j
- categorizes similar individual changes by subject and related SER section.
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89090602D7 890828
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-PDR ADOCK 0500044" A
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400 North Olive Street LB 81 Dallas, Texas 75201
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TXX-89635 August-28' 1989-Page 2 of 2 5.
The bold / overstrike version of the revised FSAR pages referenced by:the detailed description / justification'for the changes identified above..The bold / overstrike version facilitates review of-the revision by highlighting each addition of new text in. bold type font
- and overstriking with a slash (/) the portion of the text that is deleted.
Sincerely, k'
William J. Cahill'. Jr.
By:
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RogeI/ D. Walker Manager, Nuclear Licensing
'HCP/ deb Attachment-c - Mr. R. D. Martin, Region IV Resident' Inspectors..CPSES (3) l I-L L
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-Attachment to TXX-89635 August 28, 1989 Advance FSAR Submittal Concerning Fracture.Ye.ughness of the Main Steam and Feedwater System Materials Item 1~
Draft Revised FSAR Pages 2
Item 2 Detailed Description / Justification for 3
Changes
. Item 3 Related SCR Section 4 and 5 Item 4 Bullet Title 6.
Item 5 Bold /0verstrike Version of Revi'ed FSAR 7
s Pages Page 1 of 7 l
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_____________..._____.____________._1
Attaciunent; to' TXX-89635 August 28, 1989 CPSES/FSAR Page 2,of 7 DRAFT meet. the specifications of the NSSS vendor (Reference 1) and (Reference 2) EPRI~ guidelines, except where industry practice and/or bkN fb CPSES technical evaluations exceed and improve those specifications.
15 41)(d 1.,t 10=
.In the event of a steam generator tube leak, additional amine is fed
'to'the steam generator.
The amine counters the effect of the borated primary coolant, thus allowing proper adjustment of the pH.
Operation in the basic pH range causes the disproportionation of iodine in solution to iodate and iodide. This causes a decrease in the ratio'ofsiodine in the gaseous phase to that in solution.
Steam generator blowdown is not flashed but cooled in a heat exchanger and is then demineralized, as described in Section 10.4.8.
In the condenser, as in the steam generator, operation at basic pH decreanes the gaseous phase iodine. Thus, only minimal amounts of iodine are expelled through the condenser vacuum pumps.
Leakage detection and' monitoring of water chemistry is accomplished by the process sampling system which is described in Section 9.3.2.
Iodine partition coefficients based on the expected pH levels are 0.01 in the steam generator and 0.15 in the condenser.
10.3.6 MAIN STEAM AND FEEDWATER SYSTEM MATERIALS The material specifications used in the Containment pressure boundary are listed in Tables 10.3-6 through 10.3-9.
10.3.6.1 Fracture Touchness All pressure-retaining ferritic materials in the Containment pressure boundary are impact-resistance tested in accordance with NC 2300 and NB 2300 of the ASME B&PV Code,Section III, mentioned in Section DRAFT 5.2.4.
For the pressure retaining ferritic materials subject to the requirements of NC-2300 of ASME B&PV Code, Division 1.Section III, fracture analysis to demonstrate acceptability in lieu of impact testing will be used when specifically allowed in the design specification.
Drsft Version 10.3-22 f
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w m v n ~n uu DETAILED DESCRIPTION
.~Aktach:3nt to TXX-89535
-.1.. August'28, 1989
'FS[Ilaggof7 (as amended)
Gr0UD DescriDtien i
10.3-22 2-Allows the fracture toughness of the main steam and
.feedwater system materials to be determined by fracture analysis in lieu of impact testing, if permitted by the design specification.
Revision:
The ASME Code Section III Division 1, Subsection NC-2300 (1974 Ed. including 574 addenda) states that the design specifications shall state whether or not impact testing is required for the pressure reteining material of which the compecent is constructed.
Fracture analysis in lieu of impact testing for these compor,ents have been performed to ensure its safety function. The design specifications have been revised to include the impact testing requirements and to allow fracture analysis in'11eu of impact testing for certain materials.
FSAR Change Request Number: 88-326 Related SER Section: 10.3.3 SER/SSER Impact: No e
- . n f.Attachrnt to TXX-89635
, August 28,11989 Pagg4of7:
M-against tornado. missiles and high-and moderste-energy pipe breaks, and the MSIV closure time.
Therefore, the system is acceptable.
- 10.3.2 Main Steam Supply System (Downstream of the Main Steam Isolation Valves)
- 4 This section of'the report evaluates the nonsafety-related portion of the main steam system, downstream of the MSIVs.up to the turbine stop valves.
The portion l
of tha main staam system is evaluated only as it may affact the safaty-related portion of the system in the event of a main staam line break, as oiscussed in Issue No. 1 in NUREG-0138.
The scope of the review of the main steam sucoly I
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. system (between the MSIVs and up to and including the turbine stoo valves) included system descriptive information in Section 10.3 of the FSAR, flow charts and diagrams.
The main steam system for each unit is designed to deliver steam from'the four.
steam generators to the high pressure turbine.
The main steam-and turbine steam
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systems provide steam to their respective moisture-separator / reheaters, main and auxiliary feedwater pump turbines, turbine gland sealing system, feedwiter heaters, and turbine bypass system.
The applicant has provided a listing of nonsafaty grade valves in lines branchir off the main steam lines downstream of the MSIVs.
If a main steam line breaks inside containment at the same time an MSIV on one of the other main steam lines fails, the plant can still be safely shut down.
The blowdown of the second steam generator.through those branch lines containing normally open valves will not preclude safe shutdown because the plant will still have the required two steam generators available to shut down the plant.
The design criteria and bases and design of the main steam supply system maet.
the acceptance criteria in Section II of SRP 10.3.
Therefore, based on its review, the staff concludes that the' main steam supply system between the cain steam isolatieri valves and up to and inc19 ding the turbine stop valves can perform its designed functions, and is, therefore, acceptable.
10.3.3 Steam and Feedwater Systems Materials General Design Criterion 1 requires, in part, that systems important to safet be designed to quality standards commensurate with the importance to safety c the functions to be performed.
The materials utilized in the steam and feedw systems are reviewed for compliance with GDC 1.
The mechanical properties of materials selected for Class 2 and 3 components-of the steam and feedwater systems satisfy Appendix I of Section III of tne ASME Boiler and Pressure Vessel Code, and Parts A, B, or C of Section II of the Code.
The fracture toughness properties of ferritic materials satisfy the recuiremen; of the Code.
The fracture toughness tests and mechanical properties recuired by the Code provide reasonable assurance that ferritic materials will have adecuate safety margins against the possibility of nonductile behavior or raci propagating fracture.
10-5
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- AhachmenttoTXX-89635 a
,JAugust 28 1989 0
Page 5 of 7 The controls imposed upon dustenitic with Regu' atory Guices 1.31 and 1.44, er inlinless steel are either in accorda l
which have praviously been acceptao by the staff.accordance the positions.and.m Fabrication and neat tee.
practices performed in accercance.with th?se recommendations provi
. assurance that gicrofissurf9g and 3 rsss corrosion crecking will not occur d la the desigD life of the plirt.
able imourities in nonmetallic thermal insula?. ion used on
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steel comoonents'of the steam and feedwater systens are in ac:ordar.;? wi n Regulatory Guide 1.35.
t Welcers are not qualified Specifically for limitad accass as recuirec by Psgulato y Guice 1.71.
However, the production control; imposeu by the manufacturer
- are at least as effeccive as the specific recommendations of Regulatory Guida 1.73.
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positions given in Regulatory Guide 1.37 and the r National Standards Institute (ANSI) Standard N Systems and Associated Ccmponents During Construction Phase of Plant.s."
Low-elloy steel is not uti'iztd for main stesm or feedwater systems compo Therefore, Eegu?atory Guice 1.50, " Control of Preheat Temperatur ef. Low-Alloy Steel " is not applicable.
2 Tutular products are nondestructively examined in accordance with the Co Cenfermance with the coces, standards, and Regulatory Guide menticted co and for meeting, ir part, the requirements of GDC 1.an acceptab s
10.4 Other Features 10.4.1 Main Condenser The main condenser is designed to function as a heat sink for the turbine and collect condensate flows for return to'the steam gene denser transfers heat to the once-through circulating water system which use The main con-water from Squaw Creek Reservoir.
The main condenser is not required to effect or support safe shutdown of t reactor or to perform in the operation of reactor safety features.
condenser design ingludes provisions for hotwell storage of the concensata and The main feedwater systems,'which is enough for approximately a 5 min suoply conditions.
Offgas from the main condenser is processed in the concenser evacuation system.
This system is discussed in Section 10.4.2 belcw.
The main condenser is designed to accept full-load exhaust steam from the m turbine and up to 40% of the main steam flow from the turbine bypass system "Tne welcing sucervisor selects the most highly skilled to do limited access welds, and butt welds in the systems are nondestructively inspectec.
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10-5 m____
Attsciunent to TXX-89635
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'Augu;t 28, 1989
'.Pege 6 of 7 y.
p, 10.3.3 Steam and Feedwater Stilgms Materials EMTB 2.
The FSAR has been revised to allow fr:cture afialysis in lieu of impact testing for pressure retaining ferritic materials subject to the requirements of NC-2300 of ASME Code y
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Attacliment t TXX-89635
> August 28, 1989
.CPSES/FSAR W
Page 7 of'7 C
meet the specifications of the.NSSS vendor (Reference 1) and
[
(P.eference 2) EPRI guidelines, except where industry practice and/or
.of CPSCS technical evaluations exceed and improve those specifications.
LCY
'10 In the event of a steam generator tube leak, additional amine is fed to.the steam generator.
The amine counters the effect of the borated primary coolant, thus allowing proper adjustment of the pH.
Operation in the basic pH range causes the disproportionation of iodine in so16 tion to iodate and iodide. This causes a decrease in.
the ratio of iodine in the Oaseous phase to that in solution. Steam generator blowdown is not flashed but cooled in a heat exchanger and is then demineralized, as described in Section.10.4.8.
In the condenser, as in the steam generator, operation at basic pH decreases the gaseous phase iodine.
Thus, only minimal aeounts of iodine are j
expelled through the condenser vacuum pumps.
'eakage detection and monitoring of water chemistry is accomplished by the process sampling system which is described in Section 9.3.E.
16 dine partition coefficients based on the expected pH levels are 0.01 in the steam generator and 0.15 in the condenser.
I 10.3.6 MAIN STEAM AND FEEDWATER SYSTEM MATERIALS j
The material specifications used in the Containment pressure boundary are listed in Tables 10.3-6 through 10.3-9.
10.3.6.1 Fracture Touchness I
All pressure retaining ferritic materials b the Containment pressure boundary are impact-resistance tested in accordance with NC 2300 and WB g300 of the ASME bikPV Ccde,Section III, mentioned in Section l
5.2.4.
For the pressure retaining ferritic materials subject to the requirements of NC-2300 of ASME S&PV Code, Division 1.Section III, fracture analysis t? de;nonstrate acceptability in lieu of impac.t testing will be used when specifically allowed in the design I
specification.
Bold /0verstrike 10.3-22 Version i
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