GNRO-2012/00107, Vibration Data Report and Commitment Change
| ML12254A178 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 09/06/2012 |
| From: | Ford B Entergy Operations |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| GNRO-2012/00107 | |
| Download: ML12254A178 (12) | |
Text
Entergy Operations, Inc.
1340 Echelon Parkway Jackson, MS 39213 Bryan S. Ford Sr. Manager, Licensing Tel. (601) 368-5516 GNRO-2012/00107 September 6, 2012 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
SUBJECT:
Vibration Data Report and Commitment Change Grand Gulf Nuclear Station, Unit 1 Docket No. 50-416 License No. NPF-29
REFERENCES:
- 1. Entergy Operations, Inc. letter to the NRC (GNRO-2012/00079),
Summary Report of Replacement Steam Dryer Data - Responses to Requests for Additional Information, August 7, 2012 (ADAMS Accession No. ML12221A198)
- 2. Entergy Operations, Inc. letter to the NRC (GNRO-2011/00033),
Supplemental Information - Extended Power Uprate, September 9, 2011 (ADAMS Accession No. ML112521284)
Dear Sir or Madam:
In Reference 1, Entergy Operations, Inc. (Entergy) committed to provide vibration data along with acceptance limits for the main steam line (MSL) and the MSL safety relief valves (SRVs) for Grand Gulf Nuclear Station based on data collected at various power plateaus during the Extended Power Uprate (EPU) power ascension testing program. The vibration data collected at ~4306 MWt [110% of 3898 MWt, the previous licensed thermal power (PLTP)] is provided in the attachment to this letter.
In addition to transmitting the vibration data report, by this letter Entergy is notifying the NRC of a change to a commitment made in Reference 2. Specifically, the commitment previously stated:
EPU startup testing would be performed as described in Attachment 9, Extended Power Uprate Startup Test Plan, with the exception of EPU Test 10 - IRM Performance.
The EPU Startup Test Plan specifies EPU Tests 100, Main Steam and Feedwater Piping Vibration, and 101, Plant Parameter Monitoring, to be performed during power ascension to EPU conditions (4408 MWt) from 100% PLTP in step increases of 2.5% reactor power.
Entergy has changed the commitment to read as follows (changes in italics):
GNRO- 2012/00107 Page 2 of 2 EPU startup testing would be performed as described in Attachment 9, Extended Power Uprate Startup Test Plan, with the exception of EPU Test 10 - IRM Performance. In addition, performing EPU Tests 100 and 101 at Test Condition (TC) 12.5 may be delayed until TC EPU at the test directors direction provided acceptable performance is demonstrated at TC 10.
This change allows EPU Tests 100 and 101 to be performed at TC EPU, the final power ascension test plateau at 4408 MWt, vs. TC 12.5 at 4306 MWt, a 0.5% difference.
This change was discussed with the NRC Project Manager for GGNS on August 31, 2012.
The evaluation of this change is available for review at the site.
If you have any questions or require additional information, please contact Guy Davant at (601) 368-5756.
This letter contains no new regulatory commitments.
Sincerely, BSF/ghd
Attachment:
Vibration Data for the Main Steam Line Piping and Safety Relief Valves -
4306 MWt (110% PLTP) cc: Mr. Elmo E. Collins, Jr. NRC Senior Resident Inspector Regional Administrator, Region IV Grand Gulf Nuclear Station U. S. Nuclear Regulatory Commission Port Gibson, MS 39150 612 East Lamar Blvd., Suite 400 Arlington, TX 76011-4005 U. S. Nuclear Regulatory Commission State Health Officer ATTN: Mr. A. B. Wang, NRR/DORL (w/2) Mississippi Department of Health ATTN: ADDRESSEE ONLY P. O. Box 1700 ATTN: Courier Delivery Only Jackson, MS 39215-1700 Mail Stop OWFN/8 B1 11555 Rockville Pike Rockville, MD 20852-2378
ATTACHMENT GRAND GULF NUCLEAR STATION GNRO-2012/00107 VIBRATION DATA FOR THE MAIN STEAM LINE PIPING AND SAFETY RELIEF VALVES 4306 MWt (110% PLTP)
Attachment to GNRO-2012/00107 Page 1 of 9 VIBRATION DATA FOR THE MAIN STEAM LINE PIPING AND SAFETY RELIEF VALVES 4306 MWt (110% PLTP)
I. Main Steam Line (MSL) Piping Vibration Data and Acceptance Limits Table 1, below, contains the results from the MSL piping vibration testing performed as part of the GGNS Extended Power Uprate (EPU) Power Ascension Test Plan (PATP) at 4306 MWt
[110% of 3898 MWt, the previous licensed thermal power (PLTP)].
The measured accelerations were taken in the major axes for each of the nodes. A band pass filter (RMS) for the test data was applied based on:
- Lower Limit - Capturing frequencies below the lowest piping frequency which corresponds to the highest piping stresses. Generally, this number is higher than 1 Hz, which typically contains voltage drift and DC signals that need to be removed.
- Upper Limit - The upper limit frequency should be sufficiently high so that there is no significant modal participation on the maximum piping stresses. Also, the intent is to remove the high frequency noise, generally above 100 Hz.
The acceptance criteria are based on applying a constant 1g acceleration spectrum to the piping model and determining the maximum stress. The maximum stress was compared with the OM criteria alternating stress allowable per ASME OM-S/G-1997, Standards and Guides for Operation and Maintenance of Nuclear Power Plants. The resulting ratio was used to modify the output accelerations at the location for each of the test points.
Node 1008 of MSL-A has reported data that contained intermittent high-amplitude spikes.
These types of spikes were neither seen in the corresponding data for the other valves at the same valve location (top) nor in the data of at any of the nodes. For these reasons, the data at this location was deemed unusable.
Node 3010 of MSL-C has also reported data that indicates a failure in the mounting system.
Two sets of data were retrieved at the 105% power plateau. One was taken directly after the plateau was reached and a subsequent set was taken before the ascension to the 107.5%
plateau. While the plant data indicated a small increase in flow, there was a markedly higher increase in the X (longitudinal), Y (vertical), and Z (lateral) acceleration at Node 3010 on MSL-C. This magnitude increase for Node 3010 of MSL-C is in excess of 2 standard deviations above the response noted for the other 15 SRVs. For this reason, the data at this location was also deemed unusable.
Attachment to GNRO-2012/00107 Page 2 of 9 Table 1 ACCEL. ACCEL.
PIPING MONITOR MEASURED LIMIT POINT LEVEL 2/
DESCRIPTION/ NOTES LOC./DIR. ACCEL (g) LEVEL 2 / NUM. LEVEL 1 SEGMENT LEVEL 1 (g) MARGIN (%)
Piping associated with Non-B21-F041A X N/A 0.720 / 1.440 1X N/A Operable (Top of Valve)
Sensor MSL-A, Node 1008 Piping associated with Non-B21-F041A Y N/A 0.160 / 0.320 1Y N/A Operable (Top of Valve)
Sensor MSL-A, Node 1008 Piping associated with Non-B21-F041A Z N/A 0.671 / 1.341 1Z N/A Operable (Top of Valve)
Sensor MSL-A, Node 1008 Piping associated with B21-F041A X 0.260 0.447 / 0.893 2X 41.8 / 70.9 Acceptable (Actuator)
MSL-A, Node 1010 Piping associated with B21-F041A Y 0.216 0.231 / 0.461 2Y 6.5 / 53.1 Acceptable (Actuator)
MSL-A, Node 1010 Piping associated with B21-F041A Z 0.190 0.434 / 0.868 2Z 56.2 / 78.1 Acceptable (Actuator)
MSL-A, Node 1010 Piping associated with B21-F051A X 0.180 0.349 / 0.697 3X 48.4 / 74.2 Acceptable (Actuator)
MSL-A, Node 2010 Piping associated with B21-F051A Y 0.219 0.224 / 0.447 3Y 2.2 / 51.0 Acceptable (Actuator)
MSL-A, Node 2010 Piping associated with B21-F051A Z 0.222 0.389 / 0.778 3Z 42.9 / 71.5 Acceptable (Actuator)
MSL-A, Node 2010 Piping associated with B21-F047A X 0.164 0.420 / 0.840 4X 61.0 / 80.5 Acceptable (Actuator)
MSL-A, Node 4010
Attachment to GNRO-2012/00107 Page 3 of 9 ACCEL. ACCEL.
PIPING MONITOR MEASURED LIMIT POINT LEVEL 2/
DESCRIPTION/ NOTES LOC./DIR. ACCEL (g) LEVEL 2 / NUM. LEVEL 1 SEGMENT LEVEL 1 (g) MARGIN (%)
Piping associated with B21-F047A Y 0.008 0.310 / 0.619 4Y 97.4 / 98.7 Acceptable (Actuator)
MSL-A, Node 4010 Piping associated with B21-F047A Z 0.216 0.474 / 0.948 4Z 54.4 / 77.2 Acceptable (Actuator)
MSL-A ,Node 4010 Piping associated with B21-F051B X 0.017 0.701 / 1.402 5X 97.6 / 98.8 Acceptable (Top of Valve)
MSL-B, Node 1008 Piping associated with B21-F051B Y 0.150 0.185 / 0.370 5Y 18.9 / 59.5 Acceptable (Top of Valve)
MSL-B, Node 1008 Piping associated with B21-F051B Z 0.422 0.756 / 1.512 5Z 44.2 / 72.1 Acceptable (Top of Valve)
MSL-B, Node 1008 Piping associated with B21-F051F X 0.006 0.389 / 0.778 6X 98.5 / 99.2 Acceptable (Actuator)
MSL-B, Node 3010 Piping associated with B21-F051F Y 0.039 0.212 / 0.424 6Y 81.6 / 90.8 Acceptable (Actuator)
MSL-B, Node 3010 Piping associated with B21-F051F Z 0.362 0.436 / 0.872 6Z 17.0 / 58.5 Acceptable (Actuator)
MSL-B, Node 3010 Piping associated with B21-F041F X 0.634 0.645 / 1.290 7X 1.7 / 50.9 Acceptable (Top of Valve)
MSL-B, Node 4008 Piping associated with B21-F041F Y 0.171 0.181 / 0.362 7Y 5.5 / 52.8 Acceptable (Top of Valve)
MSL-B, Node 4008 Piping associated with B21-F041F Z 0.733 0.800 / 1.600 7Z 8.4 / 54.2 Acceptable (Top of Valve)
MSL-B, Node 4008
Attachment to GNRO-2012/00107 Page 4 of 9 ACCEL. ACCEL.
PIPING MONITOR MEASURED LIMIT POINT LEVEL 2/
DESCRIPTION/ NOTES LOC./DIR. ACCEL (g) LEVEL 2 / NUM. LEVEL 1 SEGMENT LEVEL 1 (g) MARGIN (%)
Piping associated with B21-F041K X 0.432 0.663 / 1.326 8X 34.8 / 67.4 Acceptable (Top of Valve)
MSL-B, Node 6008 Piping associated with B21-F041K Y 0.086 0.229 / 0.457 8Y 62.4 / 81.2 Acceptable (Top of Valve)
MSL-B, Node 6008 Piping associated with B21-F041K Z 0.409 0.677 / 1.353 8Z 40.0 / 69.8 Acceptable (Top of Valve)
MSL-B, Node 6008 Piping associated with B21-F041C X 0.695 0.701 / 1.402 9X 0.9 / 50.4 Acceptable (Top of Valve)
MSL-C, Node 1008 Piping associated with B21-F041C Y 0.113 0.185 / 0.370 9Y 38.9 / 69.5 Acceptable (Top of Valve)
MSL-C, Node 1008 Piping associated with B21-F041C Z 0.696 0.756 / 1.512 9Z 7.9 / 54.0 Acceptable (Top of Valve)
MSL-C, Node 1008 Piping associated with Non-B21-F051C X N/A 0.389 / 0.778 10AX N/A Operable (Actuator)
Sensor MSL-C, Node 3010 Piping associated with Non-B21-F051C Y N/A 0.212 / 0.424 10AY N/A Operable (Actuator)
Sensor MSL-C, Node 3010 Piping associated with Non-B21-F051C Z N/A 0.436 / 0.872 10AZ N/A Operable (Actuator)
Sensor MSL-C, Node 3010 Piping associated with B21-F047G X 0.376 0.645 / 1.290 10BX 41.7 / 70.9 Acceptable (Top of Valve)
MSL-C, Node 4008 Piping associated with B21-F047G Y 0.047 0.181 / 0.362 10BY 74.0 / 87.0 Acceptable (Top of Valve)
MSL-C, Node 4008
Attachment to GNRO-2012/00107 Page 5 of 9 ACCEL. ACCEL.
PIPING MONITOR MEASURED LIMIT POINT LEVEL 2/
DESCRIPTION/ NOTES LOC./DIR. ACCEL (g) LEVEL 2 / NUM. LEVEL 1 SEGMENT LEVEL 1 (g) MARGIN (%)
Piping associated with B21-F047G Z 0.649 0.800 / 1.600 10BZ 18.9 / 59.4 Acceptable (Top of Valve)
MSL-C, Node 4008 Piping associated with B21-F047L X 0.526 0.663 / 1.326 10CX 20.7 / 60.3 Acceptable (Top of Valve)
MSL-C, Node 6008 Piping associated with B21-F047L Y 0.212 0.229 / 0.457 10CY 7.4 / 53.6 Acceptable (Top of Valve)
MSL-C, Node 6008 Piping associated with B21-F047L Z 0.381 0.677 / 1.353 10CZ 43.7 / 71.8 Acceptable (Top of Valve)
MSL-C, Node 6008 Piping associated with B21-F047D X 0.267 0.720 / 1.440 10DX 62.9 / 81.5 Acceptable (Top of Valve)
MSL-D, Node 1008 Piping associated with B21-F047D Y 0.153 0.160 / 0.320 10DY 4.4 / 52.2 Acceptable (Top of Valve)
MSL-D, Node 1008 Piping associated with B21-F047D Z 0.291 0.671 / 1.341 10DZ 56.6 / 78.3 Acceptable (Top of Valve)
MSL-D, Node 1008 Piping associated with B21-F047D X 0.400 0.447 / 0.893 10EX 10.5 / 55.2 Acceptable (Actuator)
MSL-D, Node 1010 Piping associated with B21-F047D Y 0.153 0.231 / 0.461 10EY 33.8 / 66.8 Acceptable (Actuator)
MSL-D, Node 1010 Piping associated with B21-F047D Z 0.150 0.434 / 0.868 10EZ 65.4 / 82.7 Acceptable (Actuator)
MSL-D, Node 1010 Piping associated with B21-F014D X 0.198 0.349 / 0.697 10FX 43.3 / 71.6 Acceptable (Actuator)
MSL-D, Node 2010
Attachment to GNRO-2012/00107 Page 6 of 9 ACCEL. ACCEL.
PIPING MONITOR MEASURED LIMIT POINT LEVEL 2/
DESCRIPTION/ NOTES LOC./DIR. ACCEL (g) LEVEL 2 / NUM. LEVEL 1 SEGMENT LEVEL 1 (g) MARGIN (%)
Piping associated with B21-F014D Y 0.089 0.224 / 0.447 10FY 60.3 / 80.1 Acceptable (Actuator)
MSL-D, Node 2010 Piping associated with B21-F014D Z 0.170 0.389 / 0.778 10FZ 56.3 / 78.1 Acceptable (Actuator)
MSL-D, Node 2010 Piping associated with B21-F051D X 0.399 0.420 / 0.840 10GX 5.0 / 52.5 Acceptable (Actuator)
MSL-D, Node 4010 Piping associated with B21-F051D Y 0.296 0.310 / 0.619 10GY 4.5 / 52.2 Acceptable (Actuator)
MSL-D, Node 4010 Piping associated with B21-F051D Z 0.369 0.474 / 0.948 10GZ 22.2 / 61.1 Acceptable (Actuator)
MSL-D, Node 4010 Piping associated with Pipe Support N11G001H14 X 0.089 0.213 / 0.426 15X 58.2 / 79.1 Acceptable Turbine Bldg.
MSL-D, Node 412 II. Main Steam Safety Relief Valve (SRV) Vibration Data and Acceptance Limits Table 2, below, contains the results from the SRV vibration testing performed as part of the GGNS EPU PATP at 4306 MWt (110% PLTP).
The resultant measured acceleration represents the combined peak accelerations reported by the tri-axial accelerometer at the particular node. This peak was gathered from the time-history data after band-pass filtering (2 - 250Hz) and DC-offset removal.
Node 1008 of MSL-A has reported data that contained intermittent high-amplitude spikes.
These types of spikes were neither seen in the corresponding data for the other valves at the same valve location (top) nor in the data of at any of the nodes. For these reasons, the data at this location was deemed unusable and the other limits related to MSL-A were adjusted to account for this.
Node 3010 of MSL-C has also reported data that indicates a failure in the mounting system.
Two sets of data were retrieved at the 105% power plateau. One was taken directly after the plateau was reached and a subsequent set was taken before the ascension to the 107.5%
Attachment to GNRO-2012/00107 Page 7 of 9 plateau. While the plant data indicated a small increase in flow, there was a markedly higher increase in the X (longitudinal), Y (vertical), and Z (lateral) acceleration at Node 3010 on MSL-C. This magnitude increase for Node 3010 of MSL-C is in excess of 2 standard deviations above the response noted for the other 15 SRVs. For this reason, the data at this location was also deemed unusable.
PSD comparisons were made of the MSL response at SRV monitoring points on two valves at Nodes 1008 and Node 3010. The PSD comparison for X, Y, and Z response shows a large change in frequency response through much of the 1- 250Hz range at Node 3010 and only a small change in magnitude at the Node 1008 location. The three accelerometers at Node 3010 are mounted on the same block and strapped to the actuator. It is expected that the straps have loosened and the channel has shifted. Therefore, the measured response is most likely being affected by the response of the accelerometer mounting system and this measured response must be discounted. Based on the current methodology for developing limits through analytical methods, the limits for the other acceleration locations for the MSL-C do not need to be adjusted to account for the erroneous data at Node 3010 of MSL-C.
Table 2 COMP./PIPING ACCEL. ACCEL.
POINT MONITOR ACCEL.
DESCRIPTION / MEASURED MARGIN NOTES NUM. LOC./DIR. LIMIT (g)
SEGMENT (g) (%)
B21-F041A X 0.00 0.00 0 Non-Op Sensor Top of Valve 1 Y 0.00 0.00 0 Non-Op Sensor MSL-A, Node 1008 Z 0.00 0.00 0 Non-Op Sensor B21-F041A X 3.78 1.17 68.97 Actuator 2 Y 3.77 1.15 69.46 Acceptable MSL-A, Node 1010 Z 3.78 1.17 68.97 B21-F051A X 3.78 0.81 78.54 Actuator 3 Y 3.77 0.95 74.75 Acceptable MSL-A, Node 2010 Z 3.78 0.81 78.54 B21-F047A X 3.78 0.77 79.65 Actuator 4 Y 3.77 0.01 99.75 Acceptable MSL-A, Node 4010 Z 3.78 0.77 79.65 B21-F051B X Top of Valve 5 Y 4.03 1.57 61.06 Acceptable MSL-B, Node 1008 Z B21-F051F X 3.78 1.33 64.89 Actuator 6 Y 3.77 1.51 60.03 Acceptable MSL-B, Node 3010 Z 3.78 1.33 64.89 B21-F041F X Top of Valve 7 Y 4.03 3.39 15.76 Acceptable MSL-B, Node 4008 Z B21-F041K X Top of Valve 8 Y 4.03 1.71 57.50 Acceptable MSL-B, Node 6008 Z
Attachment to GNRO-2012/00107 Page 8 of 9 COMP./PIPING ACCEL. ACCEL.
POINT MONITOR ACCEL.
DESCRIPTION / MEASURED MARGIN NOTES NUM. LOC./DIR. LIMIT (g)
SEGMENT (g) (%)
B21-F041C X Top of Valve 9 Y 4.03 4.51 -12.04 See Note 1.
MSL-C, Node 1008 Z B21-F051C X 0.00 0.00 0.00 Non-Op Sensor Actuator 10a Y 0.00 0.00 0.00 Non-Op Sensor MSL-C, Node 3010 Z 0.00 0.00 0.00 Non-Op Sensor B21-F047G X Top of Valve 10b Y 4.03 2.66 34.02 Acceptable MSL-C, Node 4008 Z B21-F047L X Top of Valve 10c Y 4.03 1.57 60.96 Acceptable MSL-C, Node 6008 Z B21-F047D X Top of Valve 10d Y 4.03 1.47 63.53 Acceptable MSL-D, Node 1008 Z B21-F047D X 3.78 2.50 33.89 Actuator 10e Y 3.77 1.03 72.79 Acceptable MSL-D, Node 1010 Z 3.78 2.50 33.89 B21-F041D X 3.78 1.12 70.41 Actuator 10f Y 3.77 0.91 75.75 Acceptable MSL-D, Node 2010 Z 3.78 1.12 70.41 B21-F051D X 3.78 1.40 62.81 Actuator 10g Y 3.77 0.50 86.83 Acceptable MSL-D, Node 4010 Z 3.78 1.40 62.81 Note 1: Based on the vibration data from the SRV, the acceleration level for valve Q1B21-F041C has reached the limit established based on qualification testing of the valves and actuators with conservative assumptions for endurance limits based on the peak limits of testing performed. The original acceleration limits based on testing data from Wyle Laboratories has conservatism due to the inherent limitations related to the shaker table testing. This testing configuration resulted in higher tested lateral and longitudinal accelerations than the vertical response. Revised limits have been developed at the top of valve location with analytical results developed from the use of the original ASME NB-3500 calculation based upon critical valve components for the actuator and applying a transfer function to the limits at the top of valve location.
For the horizontal accelerations measured at the top of valve, the resultant measured horizontal (lateral and longitudinal) acceleration represents the combined peak accelerations reported by the tri-axial accelerometer at the particular node in the X and Z-directions. For the vertical accelerations measured at the top of valve, these accelerations represent the vertical peak accelerations reported by the tri-axial accelerometer at the particular node in the Y-direction. The peak accelerations were gathered from the time-history data after band-pass filtering (2-250Hz) and DC-offset
Attachment to GNRO-2012/00107 Page 9 of 9 removal and compared to limits as noted above. These limits can be applied to any of the top of valve locations if needed.
These limits compared to measured values using this method are as follows:
COMP./PIPING ACCEL. LIMIT (g) ACCEL. MEASURED (g) ACCEL.
POINT MONITOR DESCRIPTION / HORIZONTAL RESULTANT HORIZONTAL RESULTANT MARGIN NUM. LOC./DIR.
SEGMENT (X/Z) & VERTICAL (Y) (X/Z) & VERTICAL (Y) (%)
B21-F041C X/Z 6.62 (X/Z) 3.80 (X/Z) 42.60 (X/Z)
Top of Valve 9 MSL-C, Node 1008 Y 3.42 (Y) 2.43 (Y) 28.95 (Y)