ML20062K571

Forwards GE Response to Questions & Comments from NRC & Purdue Univ Contractor During 931001 Meeting

ML20062K571
Person / Time
Site:	05200004
Issue date:	12/16/1993
From:	Leatherman J GENERAL ELECTRIC CO.
To:	Borchardt R NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), Office of Nuclear Reactor Regulation
References
MFN-236-93, NUDOCS 9312230001
Download: ML20062K571 (8)

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i ~ GE Nuclear Energy

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Gene:S Elewic Compay 17b Cumer Avenue kn Ja e, CA 95175 December 16,1993 MFN No. 236-93 Docket STN 52-004 Document Control Desk U.S. Nuclear Regulatory Commission Washington DC 20555 Attention: Richard W. Borchardt, Director Standardization Project Directorate

Subject:

Transmittal of Responses to NRC Questions

References:

Letter, M. Malloy to P. W. Marriott, "Regt.est for Additional Information (RAI) Regarding the Simplified Boiling Water Reactor (SBWR) Design", November 15,1993 Attached please find GE's responses to the questions and comments received from the Staff and its Purdue University contractor during the October 1,1993 meeting and transmitted in the reference letter.

Sincerely,

_. %w J. E. Leatherman SBWR Certification Manager MC-781, (408)925-2023 cc: M. Malloy, Project Manager (NRC) (2 attachments)

F. W. Hasselberg. Project Manager (NRC) (1 attachment) 210052 inwg osc l

1 9312230001 931216 PDR ADOCK 05200004 3 3090 b$

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ATTACHMENT A Requests for Information by Purdue University i

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M' sekaw esce ces tec a:st - cs se nos T PURDUE UNIVERSITY sCH0ok CP NUCWAR sNotNEIRING Addittone.1 Required Informadoas From GE About Prototype $3WR Systens

1. We need information on various system parameters lbr blowdown phase at 150 pel. We ,

are interested in the thennalhydraulic paramtem at let pet. After htSL break, information t on venel liquid level (time dependent level dos to swelling), quality, void Anecion and exact decay heat power levels will be usefbl. (Note that a sisdlar question was put to GE in our previous list of questions No. 7. but en error was made at that time in asidag fbr -  :

parameters at ISO see).

2. Please provide us with a diagma Ibat defines all water levels as ds8ned by GE (Levels 1

9) in the RFV lbr all accident sosaarios.

3. Regarding question #2 in our previous ilst of queadons, the loss coefBeist Air ODG and -

Equaliastion Line Squib Valves was given to us in tenna of 'ps!'. Should tids be 'psid',

andif so,whereitis maassed? -

4. We would like to request fbrther explanatino in reSards to Questions #3s and g3e in our previous list of questions to GE. '!his la in regenis to the design of the headers and separators in the ICS and PCG. and their associated loss aaa8 haw We need desiled design drawinss of the PCCS ed ICS ' condenser mis and modales, a well as the noncondensable line vents in the lower headas. We are unable to locate this infbetnation in any of the drawings thet have been sent to us. Tbs calculation of the loss coefBelent using the crane Technical Paper necessitates ibe assumpdan of shale pbase flow in the -

condenser tubes. How is tids issue appsonched by GE since the upper header will have steam and noncondensables, the <=taa= tubes will have twophase mixture, and the lower header _ will contain stratified twophase mixture of condensass and noncondensables?

5. We would like so request inors infonnadan on the spray units in tbs suppression pool and containment. Specisoally, we need infonnation on, spray nonde diammer and mean droplet diameter or Sauter mean daimeter if avaltble.

6. What type of quick <perating valves wars used ihr the ADS system (SRVs and DFVs)in GIST incility. Indbrmation is needed on the valve type : solenoid, pneenatic or electrio actuated bs!! or other type ofvalve and vender inibunation.

7 We need infbanation on type of pump used ihr the ibed water line? In the vohunetric Sow rate in the ausfallary !!ne connecting so the pWL kept at constant ress, during the vessel depressurizadon San 150pul to the lowest pressues (reached at 810 hours0.00938 days <br />0.225 hours <br />0.00134 weeks <br />3.08205e-4 months <br />)f.

3, Ramladen Please also provide answers to the quesdans put in the ptevlees list of questions on GIST fhcility and hs hensers.

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. ABBREVIAT10ftS ADS automatic depressurization system DPV depressurization valve FWL feedwater line GDCS gravity-driven cooling systen GIST gravity-driven cooling systes integral systems test ICS isolation condenser systee MSL main steam line Pccs passive containment :ooling system RPV reactor pressure vessel SRV safety relief valve

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1 ATTACHMENT B GE Answers to Purdue University Questions 9

Note: All answers are based on currently available data. In many cases the data are preliminary and are subject to change during the SBWR design certification -

process.

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Thermal hydraulic parameters at RPV pressure of 150 psia after 1.

MSL break inside containment Assume FW pump trip and reactor sc.am at time zero. j.

Water level: (two phase) i l

Chimney 16.1 m ,

Downcomer 18.0 m '

Void Fraction:  !

Lower plenum 0.28 Channel 0.68 Bypass 0.69 Chimney 0.72 Steam dome 1.0 .

Downcomer 0.74 Time to 150 psia: 270 sec Quality @ dome: 1.0 -

Power @ 270 sec.: 5.19 x 107 wr.tts ,

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2. RPV water levels Provided in the table below are the elevations of the RPV water levels. The plant -

safety analytical limits and the nominal trip setpoints are the elevations from the vessel  ;

bottom at reference zero.

Reactor Vessel Description Plant Safety Nominal Trip Water Level Analytical Limit Setpoint (cm)

(cm) 0.5 Initiates GDCS 749.3 749.3-Equalizing line 1 Low-low water level 1009.5 1042.3 '

trip 2 Low water level trip 1409.5 1442.3  !

3 Low water level trip 1725.5 1733.3 4.5,6,7 Water level alarms N/A Note 1 8 High water level trip 1879.0 1871.3 9 FW pump trip 1936.4 Note 1  ;

Note 1: The nominal trip setpoints for the water level alarms and FW pump trip will be determined later.

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3. Loss Coefficient of GDCS Squib Cy 2 876 gpm/psido.5, measured across the valve length .

4. Additional information on ICS and PCCS condensers

a. Noncondensable vent lines in lower headers f The following reference drawings, sent to NRC in transmittal MFN No.168-93 (October 19,1993), describe the two condensers: l

2. SBW5280DMNX1105, PCCS Condenser Prototype General Arrangement j

3. SBW5280DMNX1106, Isolation Condenser General Arrangement  ;

i For the Isolation Condenser, the vent line and nozzle are identified as items 23 and 25 on the IC General Arrangement Drawing (Drawing Reference 3). On Sheet 1 in the lower right hand corner, the vent nozzle can be seen on the figure listed as

• Partial View from D". The nozzle is located on the top of the lower header, near the flange head. On Sheet 2 Detail"5" gives the dimensions of the nozzle. ,

i For the PCCS condenser, the vent line is described in the PCCS Condenser Prototype General Arrangement (Drawing Reference 2). On Sheet 1 on the left  !

hand side, the vent line is shown as an 8" schedule 40 pipe going into the lower header. Detail"C" and Section "W-W" on Sheet 2 give the dimensions of the vent line.

b. Loss coefficients [

Both the IC and the PCC have design requirements for the maximum pressure  :

loss through the units. The primary side pressure loss of the IC shall be limited -l to 20.68 kPa (3 psi) from the steam line penetration to the main drain line penetration (top of drywell top slab) at maximum expected steady state IC i condensing capacity (140 % of normal capacity). The primary sido pressure loss for the PCC condenser and vent line shall be limited to less than 850 mm of +

water at 71 C. This requirement insures that the main horizontal vents i between the drywell and wetwell remain submerged while the PCCS vents are open. Studies by the condenser designer and GE indicate that the reference designs for the SBWR will meet these requirements with margin. ,

Modeling of both the IC and PCC are done by the TRACG (GE's version of [

TRAC-BWR) computer code at GE. TRACG has the capability to calculate pressure loss for a mixture of steam and a non-condensable gas and for a two-phase mixture. User input to this calculation is based on a division of the condenser and its associated piping into " cells". Input parameters include the i geometry of the cells and local single-phase hydraulic loss factors. The equations used to calculate pressure losses from these inputs are described in J.G.M. Andersen, et al., "TRACG Model Description," NEDE-32176P (Class 3),

submitted to the NRC in February,1993. ,

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5. Containment and Suppression Pool Spray Nozzle Inforrnation GE has not performed the detailed design of the containment spray system. This  ;

system is not a safety system for the SBWR. The level of detail on the spray nozzles,  !

as asked by Purdue, is beyond the scope of the SBWR certification program. The .;

system does have the design requirement that the spray pattern should give complete coverage in the gas spaces. To achieve that, the individual sprays from the nozzles will probably overlap to ensure coverage.

6. GIST ADS valves GIST used pneumatic-actuated ball valves for the ADS system. Vender information i from the valve is below:

Gemini Valve Inc.

1 Otter Court  :

Raymond, N.H. 03077

7. SBWR Feedwater System -

There are three identical reactor feed pumps. These pumps are horizontal, centrifugal, single stage pumps, driven by adjustable speed synchronous motors. The SBWR does not have an auxiliary feedwater system, therefore the second part of this question  ;

is not applicable to the SBWR.

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8. Previous GIST Questions {

GE has responded to Purdue's earlier questions on GIST in a transmittal sent to the 1 NRC on October 20,1993 (MFN No.170-93).

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