ML072480518
| ML072480518 | |
| Person / Time | |
|---|---|
| Site: | Hope Creek  |
| Issue date: | 08/17/2007 |
| From: | Public Service Enterprise Group |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| Download: ML072480518 (30) | |
Text
{{#Wiki_filter:ATTACHMENT 2 Hope Creek Generating Station Facility Operating License No. NPF-57 NRC Docket No. 50-354 Extended -Power Uprate Non-Proprietary Version of August 17, 2007 Presentation ifiI introductions Objectives PSEG View of Acceptance Criteria Discussion of Key Points.Bias & Uncertainty Acoustic Circuit Model (ACM) Rev 4 Methodology Loading Definition from ACM Finite Element Model (FEM)Ell Limit Curves Final Reports RAI Responses ,,. H2peCreek.; 2 Demonstrate closure with May 2007 audit concerns as summarized by recent RAIs RAI matrix is provided at the end of the presentation Indicates if a report was generated to address RAI response Broken down by category (FEM, ACM, etc)Summarize the revised reportsIndicates key reasons for resubmitting Solicit NRC feedback/observations Hope Creek 3-, -- -i Acoustic Circuit Model Biases and Uncertainties @ Frequency-dependent based on QC2 data i Applied to loads from in-plant CLTP strain gage data Finite Element Model o Frequency shift +/-10% to establish peak stresses Acceptable Margin Sufficient to accommodate expected increase in loads proportional to flow 2 Qualitative Assessment of Acoustic Loadsh eCreek 4 The B&U for the load consists of: Lo Strain Gage B&U Acoustic Circuit Model Rev 4 B&U Based on QC2 data for dryer hood sensors P1 -P21 Calculated for discrete frequency ranges as defined by RAI 14.67 Which States"Frequency ranges are:[[I]Averaged 6 pressure sensors in each frequency range Expected Standpipe Resonance for HC is at 118 Hz.:HoeCreek5.t A O , ' J Biases are added algebraically. Uncertainties are combined by SRSS.Summarized in CDI Report 07-09P & CDI Technical Note 07-29P Tables 2, 3 & 4 FEM Load shifted in 2.5% intervals between -/+10% to account for frequency uncertainty Hope Creek6 I I I[[Negative.bias is ACM over prediction; Positive bias is ACM under prediction Total includes strain gage bias and uncertainty NopeCreek 7 11 Summarized in CDI Report 07-09P..HopeCreek 8 Input: 2007 in-plant data from all 4 MSLs (RAI 14.109)No reliance on previous algorithm to justify data from only 2 MSLs No reliance on Scale Model Test (SMT)The calculated B&U is added to the measured load before it is applied to the FEM[ 1]]Summarized in CDI Report 07-18P 4.HopeCreek,: 9 FEM -ANSYS 10 in the Harmonic Domain Constant 1 % structural damping across frequency range (RAI 14.78)Addresses concerns on transient time at low frequencies 64 seconds of in-plant data are used vs 2 seconds (RAI 14.96)Harmonic approach provides much more efficient means of producing accurate data Based on 2007 in-plant CLTP Loads 10 Validation is provided in Appendix B of CDI Report 07-09 (RAI 14.110)Compares results of the harmonic domain vs the transient in the time domain Stress histories are virtually identical in both Amplitude &Phase Comparison is done using the Browns Ferry Unit 1 Dryer FEM Two Specific Base Frequencies were Compared HopeCreek: 1]HopeCreek 12 Locations (All are Welds) % Frequency Alternating Shift Stress Ratio Outer vane bank/perforated inlet plate -7.5% 1.86 Middle base plate / middle vane bank -7.5% 1.89 Inlet Perforated Plate / vane bank top vertical -7.5% 2.11 plate Middle base plate / middle vane bank -7.5% 2.40 Outer base plate / outer vane bank -7.5% 2.50 All alternating stress ratios at nomi al frequency arO > 4 HopeCreek 13 Based on 2007 in-plant data No reliance on Scale Model Testing Based on Limiting Frequency shifts in 2.5% intervals between -4+10%One limit curve for each of the 8 MSL strain gage locations Summarized in Technical Note No. 07-29P hope Creek" 14.NNNNNNNEWWENNý ..--- Minimum SR-a at CLTP = 1.86 m No further reduction required due to loading B&U Level 2 is 80% of allowable (10,880 psi)Level 1 is 100% of allowable (13,600 psi)Load increase for 15% EPU is factor of 1.32 Projected stress ratio at EPU is 1.86 / 1.32 = 1.40 Load increase for 11.5% TPU is factor of 1.24* Projected stress ratio at EPU is 1.86 / 1.24 = 1.50* Target power in next operating cycle HopeCreek# 15 Load Methodology for ACM R4 CDI Report 07-09P Revision 1 Adds "low frequency hydrodynamic contribution" to increase fidelity at lower frequencies Provides bias and uncertainty information over specified frequency ranges (RAI 14.67)Load Definition CDI Report 07-18P Based solely on 2007 in-plant data and from all 4 MSLs Addresses RAIs on SMT (14.70, 80, 88, 89, 95,105 and 109)Figure 4.7 shows the [[ R] (RAI 14.73)HopeCreekl, 16 Finite Element Analysis CDI Report 07-17P Revised FEM based on CLTP 2007 in-plant data Does not rely on scale model tests, Eliminates reliance on using only 2 MS line data (RAI 14.85)Includes frequency variations from -10% to +10%Resolves issues with Rayleigh damping anchors (RAI 14.78)I]Adds explanation for model simplification (RAI 14.76)Discusses Mesh Studies (RAI 14.79)Uses 64 seconds of in-plant data (not 2 seconds) (RAI 14.96)SeCreek:?17 Limit Curves CDI Technical Note 07-29P Based solely on in-plant data Based on most conservative frequency shift Provides a limit curve for each of 8 locations Addresses RAI's 14.86, 14.104, and 14.109 HopeCreek 18 ACM, RAI 14.75 -Address problems that are prevalent in two- sensors acoustic measurement RAI's on benchmarking of SMT, etc Responses provided to specific questions, but revised submittal only uses SMT for QC and HC comparisons: Add a 118 Hz peak to the HC predicted PSD curves at EPU for HopeCreekcomparison with the QC OLTP PSDs (RAI 14.107)19 1],bopeq FEM, RAI 14.108, Use of higher factor at the root of a fillet weld WRC Bulletin 432 provides the basis for using a weld factor of 1.8 at the root of a fillet weld. The membrane plus-bending stresses and the thermal stresses are normally higher on the surface then at the embedded location and the free surface has less constraint than an embedded location. Low constraint allows the shear plane to be worked, distorted, and separations to be formed.HCGS FEM shows that the bending stresses are much larger then the membrane stresses at all the limiting steam dryer locations. Si J. .. .%. : 21 FEM, RAI 14.77, different thickness plates% Provided two simple models Provided component thicknesses at highest stressed locations HopeCreek, 22 I RAI's 14.74 SRV monitoring PSEG is in the process of developing a finite element model of the SRV's which will allow calculating vibration limits for theses valves.Hop Creekl, 23 Vane Passing Frequency Concern on SSES Steam Dryer, RAI 14.83 Responded with added information about the SSES failure and the subsequent lessons learned applied at HCGS.Recirculation pump speed range is not changing with EPU, the Steam dryer would not be exposed to any new vane passing frequencies. The Steam Dryer Inspections performed to date and those that will be performed following EPU implementation are adequate to address the concern on loads imposed by Vane Passing Frequency. HopeCreek 24
- 14. Category 67 ACM Abridged RAI Abridged response Bias and uncertainty calculation does not follow VY method. Calculate bias and uncertainty at frequency bands;New ACM report and new limit curves provide this information.
Load definition includes the revised bias and uncertainty. 73 ACM 11 I]Load Report Figure 4.7 provides the [[.]Provided as response to the RAI 75 ACM Concern on ACM definition at only two measurement locations; 84 ý ACM 11 1]85 ACM 96 ACM Demonstrate 2006 Ioads/FEM is conservative with regard to 2007 data;Use of 2-second interval for load definition; New load definition/FEM based on 2007 data.New calculations are over an order of magnitude longer.<Hope Creek, 25 70 SMT and 80... ........ ......... i .... ......... ......... ..88 SMT 89 SMT 95 SMT Questions on limit curves and stresses based on SMT;Explain inconsistencies in CDI Report 07-01 between SMT and plant data;Explain inconsistencies in CDI Report 07-01 between SMT and plant data;Explain what appears to be errors in the report;Provided limit curves based on CLTP data New FEM and limit curves rely only on in-plant data New FEM and limit curves rely only on in-plant data Revised reports not relying on SMT data.Provided as response to the RAI 105 109 SMT SMT Questions on old limit curves based on SMT data;Reliance on SMT for FEM;New limit curves provided based solely on in-plant data.New FEM report based solely on in-plant data HopeCreek 26 66 FEM Accuracy of FEM;Provided as response to the RAI 76 FEM 77 FEM 78 FEM 79 FEM 86 FEMW Limit curves 97 FEM Explain FEM modeling simplifications; Impact of different thickness plates on stresses......... ...... ......... ............ .... ...... .. .. ..... ............... .. .......................... Justify selected Rayleigh damping "hi" anchor point below 150 Hz;S ... ....... .................. .... ... ............... ........ ... ....... ........ ...Discuss mesh studies;Do not treat freq shift as uncertainty; Adjustment on weld factor for complex middle hood to end plates configuration Discussed in new FEM report.. .... ........ ..... .... .......................... .... ... .............................................. ..... ... .... ... .............. Provided as response to the RAI New FEM report uses 1% thru the entire range Discussed in new FEM report New limit curves generated that do not SRSS the frequency with the load uncertainty New FEM does not rely on this adjustment New limit curves provided are based on limiting frequency and a curve is provided for each MSL location.Commitment made as response to the RAI Provided as response to the RAI New FEM report appendix "B" 104 106 108 110 Limit Base limit curves on limiting frequency Curves and one per MSL s/g location;TPU Commit to provide NRC with full FEM for FEM TPU;FEM Justify fillet weld stress factor FEM Validate freq versus harmonic based FEM;HopeCreek 27 I 74 SRV's Discuss the SRV monitoring monitoring guidelines Provided as response to the RAI 82 SRV Cantilevered components 83 Recirc Pump VPF Qualitatively compare HC SRV to QC failed relief valve Concern on VPF impact to SSES failure Provided as response to the RAI Provided as response to the RAI 103 107 PATP MSL strain gage readings Provide proposed licensing conditions; Provide MSL PSD comparisons to QC OLTP Provided as response to the RAI Provided as response to the RAI-HopeCreek 28 2007 CLTP In- Plant Data Acoustic Circuit Model With Biases and Uncertainties Finite Element Model Limit Curves Acceptable Margin Revised reports May 2007 RAIs were answered Hopecreek 29}}