**** Press Release ****
The DAB Safety Team: December 19, 2012
Media Contact: Don Leichtling (619) 296-9928 or Ace Hoffman (760) 720-7261
SCE's Conflicting, Contradicting & Catastrophic Statements RE: Fluid Elastic Instability In SONGS Unit 2, requires NRR Complete An Investigation Before Any San Onofre Unit 2 Restart is Permitted
The DAB Safety Team has transmitted the following request to the Chairman of the NRC, Atomic Safety Licensing Board, NRC Offices of Nuclear Reactor Regulations and Nuclear Regulatory Research. The information provided below has been obtained from publicly available documents on the web.
SUMMARY: SCE is stating that FEI in Unit 2 "most likely," "may have been," or alternatively close proximity of the two tubes may have led to TTW from normal vibration. AREVA states that any claims that, "fluid-elastic instability cannot develop in Unit 2 would be inappropriate." Westinghouse is stating FEI in Unit 2 could not have occurred in these tubes.
Fluid elastic instability is both very complex and controversial, but it must be fully understood in order to design, repair and/or operate SONGS Unit 2 replacement steam generators in order to absolutely protect Southern Californian's Health, Safety, Environment and Economy.
Academic Researchers have warned about the adverse effects of FEI since the 1970's in Nuclear Steam Generators. For example, Westinghouse/Combustion Engineering designed the Palo Verde Replacement Steam Generators vibration support system, (the largest in the world) to prevent the adverse effect of FEI caused by high steam flows, high velocities and localized steam dry-outs (high void fractions). Both MHI and SCE missed the boat on Industry Benchmarking and Academic Research by not designing the SONGS Replacement Steam Generators vibration support system to prevent these adverse conditions. NRC AIT Report states that SCE Design Specification SO23-617-1 did not address specific criteria for stability ratio and does not mention fluid-elastic instability.
Recent History:
* On July 15, 1987, a steam generator tube rupture event occurred at North Anna due to fluid elastic instability.
* On February 9th, 1991, a heat transfer tube (SG tube) in a steam generator of the No. 2 pressurized water reactor at the Mihama nuclear power station of the Kansai Electric Power Company broke off due to fluid elastic instability.
* On January 31, 2012, in SONGS Unit 3, one tube started leaking radioactive coolant in one of brand new 580 million dollar replacement steam generators (RSG's) E-088 reverse-engineered by SCE and manufactured by Mitsubishi Heavy Industries, Ltd (MHI). The leak, although small, had increased enough in a short period of time to warrant the emergency shutdown of the reactor. When tested later, in March 2012, eight (8) steam generator tubes (wear range 72-100%, length of wear 23-34 inches) in the newly replaced San Onofre Unit 3 RSGs E-088 failed "in-situ" main steam line break pressure testing and therefore were plugged, after only 11 months of operation, something that had never happened before in the history of the US Nuclear fleet. Additionally, several hundred of the Alloy 690 Thermally Treated tubes were also plugged due to tube-to-tube wear. SONGS RSG's now have more damaged and/or plugged tubes than all the rest of the US reactor fleet combined. Southern Californians were very lucky, because a potentially serious nuclear accident in progress in Unit 3 was stopped. The RSGs designed by SCE and manufactured by MHI clearly violate the Code of Federal Regulations, 10 CFR Part 50, GDC 14, RCPB shall have "an extremely low probability of abnormal leakage and gross rupture."
SCE in Unit 2 Return to Service Report, Enclosure 2, Section 12.0 states, "The TTW in Unit 2 SG E-089 may have been caused by FEI, or alternatively, close proximity of the two tubes may have led to TTW from normal vibration."
SCE in its November 30 public Meeting stated that, "In Unit 2, tube-to-tube wear was caused most likely by in-plane vibrations."
AREVA in Unit 2 Return to Service Report, Attachment 6, Appendix B, Section 3.0 states, "Based on the extremely comprehensive evaluation of both Units, supplemented by thermal hydraulic and FIV analysis, assuming, a priori, that TTW via in-plane fluid-elastic instability cannot develop in Unit 2 would be inappropriate."
Westinghouse in Unit 2 Return to Service Report, Attachment 6, Appendix D, Executive Summary states "An evaluation of the tube-to-tube wear reported in two tubes in SG 2E089 showed that, most likely, the wear did not result from in-plane vibration of the tubes since all available eddy current data clearly support the analytical results that in-plane vibration could not have occurred in these tubes."
The Unit 2 steam generators were operating at higher pressures than Unit 3. The data for Unit 2 pressures reported from various root cause evaluation teams, operations personnel, and documents was within the range of 863-942 psi. The data reported for both Units 2 and 3 steam generators pressures is as follows: NRC AIT Report, Range 833-942 psi; SCE Root Cause Evaluation, 833 psi; Westinghouse Operational Assessment, ~ 838 psi. Secondary side higher pressure (863-942 psi) at 100% power produced lower void fractions (<98.5) due to higher steam saturation temperatures in the Unit 2 tube bundle region. Because of the lower void fractions, no tube-to-tube wear (fluid elastic instability) in Unit 2 was observed. Based on personnel and plant documents information, SCE has reported incorrect pressures for Unit 2 in their cause evaluation and provided wrong data to Westinghouse for Unit 2. SCE has reported correct pressures for both Units to the AIT Team. Despite the confusion, Westinghouse Assessment concluded correctly based on the ECT data that FEI did not occur in Unit 2. Westinghouse Assessment contradicts both SCE and AREVA's conclusions regarding occurrence of FEI in Unit 2.
FEI destroyed Unit 3, not Tube-to-AVB contact forces ALONE as SCE states, because: (1) Westinghouse states that none of the MHI fabrication issues were extensively analyzed in the SCE root cause evaluation, and (2) AREVA states, "The primary source of tube-to-AVB contact forces is the restraint provided by the retaining bars and bridges, reacting against the component dimensional dispersion of the tubes and AVBs. Contact forces are available for both cold and hot conditions. Contact forces significantly increase at normal operating temperature and pressure due to diametric expansion of the tubes and thermal growth of the AVBs. After fluid elastic instability develops, the amplitude of in-plane motion continuously increases and the forces needed to prevent in-plane motion at any given AVB location become relatively large. Hence shortly after instability occurs, U-bends begin to swing in Mode 1 and overcome hindrance at any AVB location," and (3) Unit 3 SG manufacturing process used more accurate and tighter tolerances which improved alignment such that tubes had more contact with AVB's.
Unless NRR determines whether Westinghouse or SCE and AREVA are correct on the Unit 2 FEI conclusions, how can NRC make the correct decisions on Unit 2's restart in the interest of Public Safety commensurate with Dr. Macfarlane's public statements: (1) SCE is responsible for the work of its vendors and contractors, and (2) There are a number of lessons that have come from the Fukushima tragic accident that are important for all countries with nuclear power reactors including: the importance of an independent regulator that operates in an open and transparent manner; the need for measures to prevent and mitigate severe accidents that displace people or contaminate land; and the significance of international cooperation to share experience and expertise to strengthen nuclear safety and security worldwide.
The DAB Safety Team seeks to assist NRR and NRC making the right decision.
###
This press release will be posted on the web at this link: San Onofre Papers.
The DAB Safety Team: Don, Ace and a BATTERY of safety-conscious San Onofre insiders plus industry experts from around the world who wish to remain anonymous. These volunteers assist the DAB Safety Team by sharing knowledge, opinions and insight but are not responsible for the contents of the DAB Safety Team's reports. We continue to work together as a Safety Team to prepare additional San Onofre Papers, which explain in detail why a SONGS restart is unsafe at any power level without a Full/Thorough/Transparent NRC 50.90 License Amendment and Evidentiary Public Hearings. For more information from The DAB Safety Team, please visit the link above.
Our Mission: To prevent a Trillion Dollar Eco-Disaster, like Fukushima, from happening in the USA.
Copyright December 19, 2012 by The DAB Safety Team. All rights reserved. This material may not be published, broadcast or redistributed without crediting the DAB Safety Team. The contents cannot be altered without the Written Permission of the DAB Safety Team Leader and/or the DAB Safety Team's Attorneys. **** Press Release ****
The DAB Safety Team: December 19, 2012
Media Contact: Don Leichtling (619) 296-9928 or Ace Hoffman (760) 720-7261
SCE's Conflicting, Contradicting & Catastrophic Statements RE: Fluid Elastic Instability In SONGS Unit 2, requires NRR Complete An Investigation Before Any San Onofre Unit 2 Restart is Permitted
The DAB Safety Team has transmitted the following request to the Chairman of the NRC, Atomic Safety Licensing Board, NRC Offices of Nuclear Reactor Regulations and Nuclear Regulatory Research. The information provided below has been obtained from publicly available documents on the web.
SUMMARY: SCE is stating that FEI in Unit 2 "most likely", "may have been", or alternatively close proximity of the two tubes may have led to TTW from normal vibration. AREVA states that any claims that, "fluid-elastic instability cannot develop in Unit 2 would be inappropriate." Westinghouse is stating FEI in Unit 2 "could not have occurred in these tubes."
Fluid elastic instability is both very complex and controversial, but it must be fully understood in order to design, repair and/or operate SONGS Unit 2 replacement steam generators in order to absolutely protect Southern Californian's Health, Safety, Environment and Economy.
Academic Researchers have warned about the adverse effects of FEI since the 1970's in Nuclear Steam Generators. For example, Westinghouse/Combustion Engineering designed the Palo Verde Replacement Steam Generators vibration support system, (the largest in the world) to prevent the adverse effect of FEI caused by high steam flows, high velocities and localized steam dry-outs (high void fractions). Both MHI and SCE missed the boat on Industry Benchmarking and Academic Research by not designing the SONGS Replacement Steam Generators vibration support system to prevent these adverse NRC AIT Report states that SCE Design Specification SO23-617-1 did not address specific criteria for stability ratio and does not mention fluid-elastic instability.
Recent History:
· On July 15, 1987, a steam generator tube rupture event occurred at North Anna due to fluid elastic instability.
· On February 9th, 1991, a heat transfer tube (SG tube) in a steam generator of the No. 2 pressurized water reactor at the Mihama nuclear power station of the Kansai Electric Power Company broke off due to fluid elastic instability.
· On January 31, 2012, in SONGS Unit 3, one tube started leaking radioactive coolant in one of brand new 580 million dollar replacement steam generators (RSG's) E-088 reverse-engineered by SCE and manufactured by Mitsubishi Heavy Industries, Ltd (MHI). The leak, although small, had increased enough in a short period of time to warrant the emergency shutdown of the reactor. When tested later, in March 2012, eight (8) steam generator tubes (wear range 72-100%, length of wear 23-34 inches) in the newly replaced San Onofre Unit 3 RSGs E-088 failed "in-situ" main steam line break pressure testing and therefore were plugged, after only 11 months of operation, something that had never happened before in the history of the US Nuclear fleet. Additionally, several hundred of the Alloy 690 Thermally Treated tubes were also plugged due to tube-to-tube wear. SONGS RSG's now have more damaged and/or plugged tubes than all the rest of the US reactor fleet combined. Southern Californians were very lucky, because a potentially serious nuclear accident in progress in Unit 3 was stopped. The RSGs designed by SCE and manufactured by MHI clearly violate the Code of Federal Regulations, 10 CFR Part 50, GDC 14, "RCPB—shall have "an extremely low probability of abnormal leakage…and gross rupture."
SCE in Unit 2 Return to Service Report, Enclosure 2, Section 12.0 states, "The TTW in Unit 2 SG E-089 may have been caused by FEI, or alternatively, close proximity of the two tubes may have led to TTW from normal vibration.
SCE in its November 30 public Meeting stated that, "In Unit 2, tube-to-tube wear was caused most likely by in-plane vibrations."
AREVA in Unit 2 Return to Service Report, Attachment 6, Appendix B, Section 3.0 states, "Based on the extremely comprehensive evaluation of both Units, supplemented by thermal hydraulic and FIV analysis, assuming, a priori, that TTW via in-plane fluid-elastic instability cannot develop in Unit 2 would be inappropriate."
Westinghouse in Unit 2 Return to Service Report, Attachment 6, Appendix D, Executive Summary states "An evaluation of the tube-to-tube wear reported in two tubes in SG 2E089 showed that, most likely, the wear did not result from in-plane vibration of the tubes since all available eddy current data clearly support the analytical results that in-plane vibration could not have occurred in these tubes."
The Unit 2 steam generators were operating at higher pressures than Unit 3. The data for Unit 2 pressures reported from various root cause evaluation teams, operations personnel, and documents was within the range of 863-942 psi. The data reported for both Units 2 and 3 steam generators pressures is as follows: NRC AIT Report, Range 833-942 psi; SCE Root Cause Evaluation, 833 psi; Westinghouse Operational Assessment, ~ 838 psi. Secondary side higher pressure (863-942 psi) at 100% power produced lower void fractions (<98.5) due to higher steam saturation temperatures in the Unit 2 tube bundle region. Because of the lower void fractions, no tube-to-tube wear (fluid elastic instability) in Unit 2 was observed. Based on personnel and plant documents information, SCE has reported incorrect pressures for Unit 2 in their cause evaluation and provided wrong data to Westinghouse for Unit 2. SCE has reported correct pressures for both Units to the AIT Team. Despite the confusion, Westinghouse Assessment concluded correctly based on the ECT data that FEI did not occur in Unit 2. Westinghouse Assessment contradicts both SCE and AREVA's conclusions regarding occurrence of FEI in Unit 2.
FEI destroyed Unit 3, not Tube-to-AVB contact forces ALONE as SCE states, because: (1) Westinghouse states that none of the MHI fabrication issues were extensively analyzed in the SCE root cause evaluation, and (2) AREVA states, "The primary source of tube-to-AVB contact forces is the restraint provided by the retaining bars and bridges, reacting against the component dimensional dispersion of the tubes and AVBs. Contact forces are available for both cold and hot conditions. Contact forces significantly increase at normal operating temperature and pressure due to diametric expansion of the tubes and thermal growth of the AVBs. After fluid elastic instability develops, the amplitude of in-plane motion continuously increases and the forces needed to prevent in-plane motion at any given AVB location become relatively large. Hence shortly after instability occurs, U-bends begin to swing in Mode 1 and overcome hindrance at any AVB location," and (3) U3 SG manufacturing process used more accurate and tighter tolerances which improved alignment such that tubes had more contact with AVB's.
Unless NRR determines whether Westinghouse or SCE and AREVA are correct on the Unit 2 FEI conclusions, how can NRC make the correct decisions on Unit 2's restart in the interest of Public Safety commensurate with Dr. Macfarlane's public statements: (1) SCE is responsible for the work of its vendors and contractors, and (2) There are a number of lessons that have come from the Fukushima tragic accident that are important for all countries with nuclear power reactors including: the importance of an independent regulator that operates in an open and transparent manner; the need for measures to prevent and mitigate severe accidents that displace people or contaminate land; and the significance of international cooperation to share experience and expertise to strengthen nuclear safety and security worldwide.
The DAB Safety Team seeks to assist NRR and NRC making the right decision.
###
This press release will be posted on the web at this link: San Onofre Papers.
The DAB Safety Team: Don, Ace and a BATTERY of safety-conscious San Onofre insiders plus industry experts from around the world who wish to remain anonymous. These volunteers assist the DAB Safety Team by sharing knowledge, opinions and insight but are not responsible for the contents of the DAB Safety Team's reports. We continue to work together as a Safety Team to prepare additional San Onofre Papers, which explain in detail why a SONGS restart is unsafe at any power level without a Full/Thorough/Transparent NRC 50.90 License Amendment and Evidentiary Public Hearings. For more information from The DAB Safety Team, please visit the link above.
Our Mission: To prevent a Trillion Dollar Eco-Disaster, like Fukushima, from happening in the USA.
Copyright December 19, 2012 by The DAB Safety Team. All rights reserved. This material may not be published, broadcast or redistributed without crediting the DAB Safety Team. The contents cannot be altered without the Written Permission of the DAB Safety Team Leader and/or the DAB Safety Team's Attorneys.
AIT: Augmented Inspection Team
AVB: Anti-Vibration Bar
CFR: Code of Federal Regulations
DAB: DAB (Don, Ace, and a Battery of Experts) Safety Team
ECT: Eddy Current Testing
FEI: Fluid Elastic Instability
FIV: Flow Induced Vibration
GDC: General Design Criteria
MHI: Mitsubishi Heavy Industries, manufacturer of the RSGs
NRC: Nuclear Regulatory Commission
NRR: [Office of] Nuclear Reactor Regulations
RC: Reactor Coolant
RCPB: RC Pressure Boundary (includes SG tubes and all other RC boundaries)
RSG: Replacement SG
SCE: Southern California Edison
SG: Steam Generator
SONGS: San Onofre Nuclear [Waste] Generating Station
TTW: Tube-to-Tube Wear
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