SAN FRANCISCO, May 19, 2010—Entergy Nuclear employees at the Palisades nuclear power station in western Michigan have been honored with the B. Ralph Sylvia Best of the Best Award for developing an innovative device that improves the inspection of reactor vessel heads.
The device, called a gimbaled head, uses ultrasonic transducers to identify irregularities within the welded steel reactor vessel head nozzles used for control rod drive mechanisms and nuclear instrumentation. A vessel head is a massive, multi-ton component that helps house the uranium fuel assemblies that are the energy source for 20 percent of U.S. electricity supplies, as well as various instruments used to operate the reactor.
Previously, engineers at the Palisades plant needed four different kinds of testing devices to complete the inspection. The gimbaled head device performs the entire inspection, conducting an even more thorough, accurate and effective examination in less time. Additional improvements have enabled the ultrasonic transducers to produce higher quality and more consistent inspection information.
“The team at the Palisades nuclear plant developed an innovative inspection device that identifies irregularities in reactor vessel nozzle welds and provides accurate, consistent results,” said Tony Pietrangelo, NEI senior vice president and chief nuclear officer. “It’s not only a better way to inspect these nozzles, it’s also far more efficient. This special tool will help identify material stresses in the early stages—before they can develop into a larger problem. The team’s vigilant, questioning approach produced an important step forward for the nuclear energy industry.”
The Best of the Best Top Industry Practice (TIP) award was presented at NEI’s annual meeting. The TIP awards recognize industry employees in 14 categories—four vendor awards, nine process awards for innovation to improve safety, efficiency and nuclear plant performance, and one award for vision and leadership. The Best of the Best Award honors the late B. Ralph Sylvia, an industry leader who was instrumental in starting the TIP awards in 1993. NEI this year received 142 entries for awards.
Other companies with employees who received awards are: American Electric Power, AREVA NP Inc., Dominion Nuclear Connecticut, Dominion Power, Exelon, Exelon Generation Co., Exelon Nuclear, FirstEnergy Nuclear Operating Co.,
Progress Energy, PSEG Nuclear, Southern Nuclear Operating Co., Tennessee Valley Authority and Westinghouse.
TIP VENDOR AWARDS
• Dominion Power employees at Virginia’s Surry power station collaborated with AREVA to win the AREVA Vendor Award for developing the Deposit Minimization Treatment process to decrease the buildup of sludge on the plant’s steam generator tubes.
Sludge buildup on the steam-producing side of the steam generator tubes had reduced steam pressure and could have affected power generation. The previous solution for cleaning such material from the tubes required harsh chemicals.
Dominion Engineering and Chemistry personnel developed a cost-effective and environmentally sound solution to eliminate the buildup and restore consistent power generation. The Deposit Minimization Treatment is a safer, simplified system that reduced deposits by 700 to 800 pounds and saved the company approximately $32 million. It does not require harsh chemicals, and waste from the process can be treated with filtration to decompose the active ingredient.
While the old system required that cumbersome equipment be connected to the steam generator in several places, the new system has smaller and fewer pieces and requires only a single connection. The equipment now can be placed in a remote location, eliminating the need for work within the reactor building and enhancing radiation safety and security. The process has application potential for other pressurized water reactors.
• Employees of Exelon at the Dresden generating station in northern Illinois collaborated with GE Hitachi Nuclear Energy to earn the GE Hitachi Nuclear Energy Vendor Award for their creation of the Control Rod Drive Tube Flushing “Vortex Tool” that removes iron oxide buildup in control rod drive guide tubes.
Iron oxide in the water flowing through the reactor can adhere to fuel assemblies and later detach during refueling, affecting control rod drive mechanisms. The previous method for removing loose iron oxide was to vacuum the guide tubes when control rod blades were replaced. However, blade replacement rarely coincided with the need to remove iron oxide buildup, and the cleaning process was time-consuming and cumbersome.
The team’s Vortex Tool can be used with the control blades in place. It deploys from the bottom of the vessel, flushes iron oxide from the control rod drive mechanism and then visually inspects tubes with a camera in a two-minute process. The tool increases equipment reliability while reducing refueling outage time and radiation exposure. The tool can be adapted for use at all boiling water reactors.
• American Electric Power employees at Michigan’s Donald C. Cook nuclear plant attained the Westinghouse Design Vendor Award for their root cause analysis of a turbine failure in 2008.
The surface of each failed turbine blade was analyzed for data about the blade loss. State-of-the-art analytical techniques revealed that three blades on two of the three turbines were subjected to several stresses exacerbated by a design fault.
By determining the root causes of the turbine blade failure, the team facilitated the necessary repairs and Donald C. Cook Unit 1’s return to service. Key lessons have been shared with the nuclear industry and will help improve turbine reliability and safety.
• Dominion Nuclear Connecticut employees at the Millstone power station were honored with the Westinghouse Combustion Engineering Design Vendor Award for accomplishing two major plant modifications while increasing safety, reducing worker radiation exposure and decreasing work time.
First, the team needed to replace reactor components known as “thimble tubes.” Underwater divers perform the job. This task had been done in the industry only five times before. Using a Westinghouse process mapping technique, the team overlaid work flow diagrams from each previous effort and analyzed every step and component down to the minute. This analysis, along with several weeks of diver training exercises, ensured that the safest and most efficient process was used to replace the thimble tubes.
The second modification was a weld overlay of unprecedented scope for nine nozzles in the reactor coolant system. The team combined process improvement tools with timed challenges in a mock-up environment to identify the most efficient repair method. The experience enabled the team to refine the process and reduce the time needed to complete it.
The techniques used in both modifications are applicable throughout the nuclear energy industry.
TIP PROCESS AWARDS
• Entergy Nuclear employees at Palisades were honored with the Maintenance Process Award and the nuclear energy industry’s B. Ralph Sylvia Best of the Best Award for developing an innovative inspection device for vessel heads (as described above).
• Exelon Nuclear and AREVA NP Inc. employees won one of two Community Relations Process Awards for developing and implementing comprehensive communications plans surrounding the transport of two massive steam generators for the Three Mile Island nuclear generating station in Pennsylvania. Two 153-foot-long transporters weighing 825 tons each made a month-long, 75-mile journey spanning parts of Pennsylvania, Maryland and 23 municipalities.
Implementing a joint communications plan developed over 18 months, Exelon and AREVA communicators used new and existing tools to ensure necessary information about the transport was available to the public, media, public officials and other key stakeholders. Their goal was to make the process as transparent, safe and smooth as possible.
The plan included open-house meetings and educational programs, advertising and notifications, and safety briefings and updates. The winners of this award embraced electronic communication, disseminating updated information via the Web and a Twitter account. They ensured that members of the public could call a dedicated phone line to learn how the transport could affect them. They stationed communicators along the transport route, walking alongside the generators throughout the process and answering questions from onlookers.
The two steam generators—a shipment more than twice as large as any load ever transported by road through Maryland or Pennsylvania—arrived safely and on time at the Three Mile Island site. The transport garnered more than 110 news stories, and more than 12,000 spectators turned out to witness the event.
• PSEG Nuclear employees at the Salem and Hope Creek generating stations received one of two Community Relations Process Awards for an outreach program that built public support for the license renewal of the Salem and Hope Creek nuclear plants and the early site permit for a potential fourth nuclear reactor at the Salem/Hope Creek complex in southern New Jersey.
The company hosted meetings with elected officials and programs with business groups and formed an active partnership with local media. The effort also ensured that stakeholders could experience nuclear energy first-hand. Plant tours, organized for a variety of community groups, featured a visit to a control room simulator and enabled visitors to learn about everything from plant design and licensing requirements to safety and security. Members of the public met with security personnel, plant management, training personnel and subject matter experts.
In all, more than 430 people toured the power stations, and more than 730 met with members of the PSEG Nuclear leadership team. The program was bolstered by a partnership with the local community college and technical schools, with establishment of a nuclear technology degree program to develop the future work force.
No contentions were filed when the license renewal application for the Salem and Hope Creek generating stations was submitted to the Nuclear Regulatory Commission, and significant community support was shown at the public license renewal meeting.
• Southern Nuclear Operating Co. employees collaborated with Westinghouse to earn the Equipment Reliability Process Award for their development of the industry’s first-of-a-kind Engineered Leak Rate Seals® that have improved the reliability of Westinghouse reactor coolant pumps. Poor seal performance can result in the shutdown of a reactor coolant pump and, consequently, the shutdown of a reactor.
Low levels of seal leak-off resulted in four forced or extended outages at Southern Nuclear power plants between 2004 and 2008. To address the issue, Southern Nuclear employees formed a subcommittee that developed and copyrighted the industry’s Engineered Leak Rate Seals. They determined the angle of the seal surface is critical to seal performance and leak-off flow. The group collaborated with Westinghouse to improve the manufacturing process to produce a seal with a more tightly controlled seal angle measured to millionths of a degree. The new seal ensures that leak-off remains within normal levels and cannot drop low enough to affect the pump’s performance.
Westinghouse now offers the Engineered Leak Rate Seals for use with Westinghouse 93A and 93A-1 type reactor coolant pumps throughout the industry. The new seals have been installed in two of Southern Nuclear’s reactors and are performing well.
• Exelon Generation Co. employees took the Nuclear Fuel Process Award for their Fuel Vendor Collaborative Management Review Process that implemented an integrated management review process across a fleet of reactors to ensure relevant issues are regularly discussed with three fuel vendors.
The process is centered on regularly reviewed performance indicators in 11 areas ranging from engineering productivity to fuel integrity and reliability. Initiatives and improvements are developed, and the fuel vendors have the opportunity to provide feedback to Exelon. This open dialogue facilitates continuous improvement and has resulted in cost savings, increases in safety and improved efficiency.
An example involves the metal control blades that move in channels within the reactor’s fuel assemblies. Durability issues were brought to management’s attention through the review process. Now, by improving the capability to predict and address interference between control blades and the channels they move within, the blades will be fully utilized through an extended, carefully monitored operating lifetime.
Easily transferable across the nuclear industry, the review process also resulted in steps to protect fuel, implemented a core design strategy to use fuel more efficiently, reduced worker radiation exposure and increased safety.
• FirstEnergy Nuclear Operating Co. employees at Beta Laboratory landed the Materials and Services Process Award for their success in upgrading integrated control system circuit cards. By developing an in-house solution based on manufacturing processes, the team enhanced the design and produced a more reliable circuit card while saving time and money.
Because integrated control system circuit card malfunctions can cause power reductions and other plant challenges, improved equipment reliability was also among the team’s top goals. The new circuit cards featured improved relay design and higher performance specifications, which enhances plant reliability and reduces the preventive maintenance needs of the plant.
All steps of the process were completed in-house including design enhancement, prototyping, manufacturing and assembly. The final step was a rigorous testing process conducted by a comprehensive automated program also developed in-house. The in-house solution upgraded a circuit card for eight percent of the cost of off-site manufacturing. This innovation saved more than $1 million and contributed to greater supply chain efficiency.
• Exelon Nuclear team members at Peach Bottom earned the Operate Plant Process Award through their development of the Exelon Jet Pump Ultrasonic Cleaning Hummingbird used to clean the jet pumps that control power level in the Pennsylvania plant’s reactor.
Jet pumps regulate power level by ensuring enough water flows in the reactor vessel to be changed into steam. Millions of gallons of water flow through the jet pumps, and the large amount of flow can result in a buildup of microscopic corrosion products. Over time, this buildup can increase vibration and reduce flow, requiring more fuel to compensate for lost generation.
The standard technique for removing corrosion from jet pumps is ultrahigh pressure cleaning that requires portions of the jet pumps to be disassembled and removed from the reactor vessel. The team developed methods to utilize an ultrasonic cleaning bath that also has been used in the nuclear energy industry to clean pressurized water reactor fuel assemblies. The method allows the jet pumps to be cleaned more often and more effectively to combat buildup before it interferes with power generation.
Most importantly, this new method of cleaning requires no jet pump disassembly. As a result, it improves safety and has a positive impact on outage scheduling.
• American Electric Power won the Plant Support Process Award for its innovative solutions during turbine restoration at the Donald C. Cook Nuclear Plant.
The loss of several turbine blades led to turbine failure and subsequent damage to the lower exhaust hoods that are the outermost casing of the turbines. Vibration created friction between the base of the exhaust hoods and the surface below, necessitating detailed inspections, leveling and repairs that included straightening bent turbine rotors.
To raise the 175-ton hood for inspections and repairs, the team used an innovative lifting technique. Instead of disassembling the hood into several pieces and repairing each separately, which could result in inconsistent adjustments, the team raised the entire hood as a single unit. This innovative method eliminated the disassembly process, thereby reducing the likelihood of a safety incident and saving time.
The team also pioneered a method to straighten three bent and damaged rotors without requiring complete disassembly. Using heat, vibration and high-speed spinning, they successfully repaired each of the 400,000 pound rotors eliminating the need for costly replacements. This project involved three million work hours and the lifting of heavy loads totaling 43 million pounds, and did so safely without a single lost time or restricted time incident.
• Tennessee Valley Authority employees at Browns Ferry Unit 1 in northern Alabama were honored with the Management Processes and Support Services Process Award for their program that resulted in the lowest occupational dose to workers at any boiling water reactor in the world.
The integrated source term reduction program reduced the amount of radioactive cobalt available to be activated and thus distributed in the plant. The multi-faceted program incorporates a variety of technologies to maintain equipment and prevent the buildup of cobalt including the application of a protective coating to key materials. X-Ray Fluorescent Technology also was used to identify cobalt that needed to be removed.
The benefits of the program are numerous. With a lower occupational dose comes a reduced need for engineering controls, respiratory protection and administrative controls on high-radiation areas. The program also has shortened outage time and improved worker efficiency. For radiation protection technicians in particular, the program allows a greater focus on improvement rather than constant monitoring. This program is expected to lower radiation exposure and yield millions of dollars in cost savings.
• Southern Nuclear Operating Co. employees at Georgia’s Plant Vogtle station were recognized with a Nuclear Training Process Award for their Training Dosimetry Simulator that creates a virtual radiation environment where workers can develop their skills to keep radiation exposure as low as possible – well below federal limits.
Previously, instructors followed trainees so they could alert the worker of higher-than-expected doses. The new method combines two technologies. First, Virtual Radiation Environment is a software program that allows a trainer to define a virtual radiation zone and assign radiation sources and areas of varying radiation levels. The second, Near-Field Electromagnetic Ranging, uses low-frequency radio technology to track worker location in real time. Together, these technologies display the exposure levels based on the worker’s location within the virtual radiation zone. It is a realistic approach that ensures workers remain protected from radiation as they gain actual work experience.
Additionally, the system maps the steps the worker will take in performing an upcoming task. By reviewing the task map, planners can eliminate unnecessary actions, minimize idle time and reduce radiation exposure thereby making the work process safer and more efficient.
TIP VISION &LEADERSHIP AWARD
• Progress Energy employees at the Shearon Harris nuclear plant are recipients of the Vision & Leadership Award for their pioneering developments in fire protection.
In 2004, the NRC approved use of the National Fire Protection Association’s performance-based standard. The Shearon Harris fire protection team has led the industry in implementing the standard, focusing on two actions in particular to improve fire protection.
First, because extreme heat can damage conventional cable, the team replaced vital and vulnerable cables with a fire-rated version that can withstand three hours of exposure up to 2,000 degrees Fahrenheit. The use of fire-rated cable in critical areas helps insure that the plant can be shut down safely in the event of fire.
Second, the team developed an early warning system that can detect fire-prone conditions before a fire can start. The new detection hardware combats fires by detecting precursor conditions. The system monitors critical equipment for signs of degradation and notifies operators so they can perform preventive maintenance before problems arise.
The Progress Energy team led the nuclear energy industry through this important strategic fire protection process. Their innovations will improve nuclear plant safety and produce significant savings across the industry.