Integrated outages increase Surry`s availability
By S.R. Harms, Westinghouse, and J.L. Downs, Surry Power Station
Through Virginia Power?s and Westinghouse?s goal-oriented planning philosophy, teamwork and commitment, average outage duration has decreased significantly
During the past 10 years Virginia Power and its nuclear steam supply system (NSSS) services vendor, Westinghouse Electric Corp., have developed a working partnership with one goal in mind: increasing the availability and capacity factors of the North Anna and Surry nuclear power stations while driving down the operating costs of the plants. The outage integration program, steam generator maintenance agreement (SGMA), and integrated radiological services program form the core of this relationship and helped Virginia Power complete one of the most successful outages in Surry Power Station?s operating history.
Surry Power Station
Surry Power Station Unit 1 is an 860-MWe, three-loop Westinghouse pressurized water reactor that began commercial operation in 1972. The plant is located approximately 17 miles upriver from Newport News, Va. It is one of four nuclear units operated by Virginia Power.
Outage success is measured by performance as compared to established goals. Seven goals were identified for Surry?s Unit 1 Cycle 13 refueling/10-year inservice inspection (ISI) outage and included maintaining outage schedule and budget parameters, preserving safety, keeping radiation exposure and radwaste generation to minimum levels, and reducing material and safety-related deferrals.
Outage goals and performance
Table 1 reviews the outage goals and actual performance. Goals like these are impossible to meet without a rock-solid commitment from station management equipped with a sound procedure. Virginia Power believes in up-front planning for outages and has a group of professionals totally devoted to outage planning. Goals are set with one mission in mind; they are to be met or exceeded. A company administrative procedure entitled OOutage Management and PlanningO provides instructions for managing and planning outage activities. All personnel involved in outage planning and scheduling activities follow it.
The OOutage Management and PlanningO procedure establishes planning milestones through a OPlan of the Plan.O The OPlan of the PlanO is a schedule identifying outage-related activities performed prior to, during, and after an outage that are required to effectively support its implementation. The OPlan of the PlanO identifies eight activities and the milestone date for their completion, including:
1. Major activities and associated work orders, parts and engineering support,
2. Pre-outage work required to support outage activities,
3. Facility requirements, including space allocation and utilities,
4. Procedure development and review,
5. Establish system windows for boundaries and tags,
6. Development of Level I, II and III schedules,
7. Plant shutdown, startup and post-maintenance testing requirements, and
8. Pre-outage readiness reviews and post-outage critiques.
Outage integration program
In 1990, Westinghouse started the outage integration program (OIP) by permanently placing a team of company personnel at the plant site. Virginia Power incorporated this team as part of its station outage organization. The team?s function is to plan, coordinate, control and direct the activities performed by Westinghouse and to provide on-site technical representation to Virginia Power. The Westinghouse team is trained in Virginia Power?s planning system, site procedures and policies.
The OIP allows all facets of the Westinghouse support groups to work together. When a component is found to require service during the outage, the team investigates the problem, gathers all the component identification information, and ties in the applicable engineering group to resolve engineering issues and develop repair procedures. The team transfers these engineering decisions to Virginia Power management, plans the work orders, develops the schedule and identifies the required parts. Any Westinghouse parts can be tracked directly by trained parts specialists who contact the factory and expedite delivery.
The team also works closely with the appropriate Westinghouse organization that repairs needed components. The OIP is led by the Westinghouse outage management team. This team is used to bind together groups contracted by Virginia Power to perform various engineering and maintenance functions.
Of all the groups coordinated by the Westinghouse team, the largest is the SGMA. The SGMA was designed to enhance steam generator operations by: Performing routine extensive inspections of the primary and secondary side during refueling stages, applying state-of-the-art methodologies for SG repairs and upgrades, installing an on-line chemistry monitoring system for feedwater control, and dedicating a team of engineers to follow the program on a daily basis.
Virginia Power and Westinghouse engineers and managers also formed an advisory committee to keep up with industry issues and transfer technical information between parties. This committee has established the recommended Obase scopeO or routine inspections that are to be performed with each outage. The inspections are tailored to conditions that may exist in specific steam generators at each of Virginia Power?s nuclear power plants. All inspections are designed to produce enough information so the team can comfortably monitor steam generator conditions.
For all services planned prior to the outage, or those contingencies that have medium-to-high probabilities during the outage, purchase orders are prepared and released prior to the start of the outage; including an engineering T&M order that can be used for miscellaneous work. The T&M order also covers necessary technical and safety evaluations during the course of steam generator services. Having these orders in place facilitates the process of crew definition, mobilization and service execution should the need arise.
Over the years the program has proven to be effective in many areas. There have been more than 20 outages performed.
From the SGMA grew the idea for the integrated radiological services program (IRSP). The IRSP group is responsible for maximizing radiation protection and decontamination resources while minimizing service costs. To accomplish these overall objectives, the program employs extensive manpower and equipment preplanning for major outage operations and utilizes experienced personnel that are accustomed to working at Virginia Power?s plants.
In an effort to build this core of experienced workers, a small staff is retained by Virginia Power on a year-round basis. This core group is responsible for the development of the IRSP contractor personnel brought in during the outages. Currently, a strong base of Virginia Power/IRSP returnees are available. The requirement to maintain a year-round staff has been reduced and now includes a program manager, a planner/supervisor and an as low as reasonably achievable engineer. This staff helps maintain continuity between Westinghouse and Virginia Power.
At the last outage for Surry Unit 1 the IRSP returnee rate was very high. Ninety-eight percent of contractors brought in for the outage had worked at a Virginia Power Site within the last year. This returnee rate contributed to in-processing and site-specific training cost savings. In addition, man-hour cost savings were passed on to Virginia Power as a result of such effective resource utilization during the outage.
Incentives are built into the program to keep both parties focused on enhanced operation and help maintain a critical eye on chemistry control. Performance targets based on Virginia Power?s corporate and site-specific goals and commitments are also incorporated in the program. To ensure everyone is committed to meeting Virginia Power?s goals, the program incorporates a performance incentive for the participating employees. Typical goals or performance measures include: radioactive waste reduction, outage performance, resource utilization, quality of service, general evaluation, man-rem (radiation exposure) reduction and containment cleanliness. The OpartnershipO instills trust and confidence and is key to successful outages year after year.
Another goal of the program is to continually develop and use robotic tooling to decrease workers exposure while performing historically high-dose SG service procedures. Core contaminated area has virtually been reduced to zero at both Virginia Power stations. This reduction in contaminated area correlated to a substantial decrease in personnel contamination events over the past six years.
The auxiliary building reclamation has been one of the major successes of this
partnership. The IRSP, along with other Westinghouse organizations, strives to meet or exceed all of the goals and measures established by Virginia Power. Surry Unit 1?s ISI/refueling outage was one of most successful outages since the partnership was formed.
All of these programs and the various site departments were pulled together by Virginia Power outage management. This group established an outage integration team, which included representatives from every department: outage planning, radiation protection, maintenance, operations, engineering, materials, security, nuclear site services, and Westinghouse. The team addresses and resolves issues pertaining to outage performance.
The outage was broken down into the following five phases:
1. Shutdown and preparation, January 22 through 31. This phase was completed on Day 10, 30 hours ahead of schedule when reactor head detensioning was started. One reactor coolant pump motor had been removed from containment, the steam generator primary side was opened for eddy current testing, and the cavity seal ring was refurbished.
2. Disassembly and offload, February 1 through 12. The second phase was completed on Day 20, 35 hours ahead of schedule including the completion of core offload. A second reactor coolant pump motor was removed from containment and both motors were reset on the pumps. Steam generator eddy current testing was completed and steam generator secondary side inspections were started.
3. Empty vessel?February 13 through March 22. Phase III was completed on Day 37, 58 hours ahead of schedule when fuel onload started. Removal of the reactor vessel lower internals, mid-loop maintenance work, 10-year ISI vessel inspection and all reactor coolant pump work was completed.
4. Reload and assembly, March 3 through 15. The fourth phase was completed on Day 51, 68 hours ahead of schedule. At this point, reactor reassembly and steam generator secondary side work was completed.
5. System closure and startup, March 15 through 27. Heatup and startup was completed on Day 64, when the unit generator was tied to the system grid. The major milestones and critical path schedule is shown in Figure 1.
As a result of meticulous planning, an outage that included a 10-year reactor vessel ISI was completed in about the same amount of time as a standard refueling outage for a reactor of this type. Through Virginia Power?s commitment, philosophy and teamwork the average outage duration has decreased from 73 to 63 days (Figure 2). This process, however, is far from being complete. Once performance goals are achieved a new set is developed to challenge the team. The success of this past outage can be attributed to pre-outage planning, communications and teamwork between a utility and its vendor for NSSS services. END
S.R. Harms has been the Westinghouse outage manager at Surry Power Stations since 1990. He has worked in various field service groups for Westinghouse in his 14 years with the company.
J.L. Downs has been superintendent of outage and planning for Virginia Power?s Surry Power Station since 1990. He has worked in various capacities in operations, engineering and planning since joining Virginia Power 19 years ago.