By Jessica D. Netter Ducharme, VP Sales and Marketing, Electrical Builders, Inc.
Planning and communication are necessary to complete any project successfully. This sentiment holds true particularly when the project involves conducting a power plant uprate, and millions of dollars are on the line each day. Plant staff and outside contractors must work in tandem to avoid miscommunication and unnecessary issues, which may lead to project delays. Prior to the scheduled outage at Exelon’s Quad Cities Nuclear Power Station Unit 1 in Cordova, Ill., Electrical Builders, Inc. (EBI) and the Quad Cities project management team had the complex task of planning a complete Isolated Phase Bus Duct (IPBD) replacement within an unprecedented 21 day window. Project planning and communication by all parties involved, coupled with EBI’s extensive IPBD experience made the aggressive schedule possible.
|The two-unit, 1,737 MW Quad Cities nuclear power plant in Cordova, Ill. Photo courtesy of Exelon Corp.|
Facts about IPBD are often overlooked and many underestimate the importance of this integral part of a power plant. The most simplistic analogy for IPBD is to compare it to a power cord. Despite its essential role, IPBD is the only component within the entire power plant that has no redundancy. For this reason, it is imperative to hire a contractor with extensive (self-performed) IPBD experience and continuity for this specialized work. Procurement agents cannot underestimate the value of this and must consider these qualifications when making a buying decision, as it will determine success or failure of the project.
Planning between EBI and Exelon began six months before the project at Quad Cities Unit 1 was scheduled to begin. A detailed project schedule was developed while scaffolding, welding, FME and rigging plans were laid out. Examining the lessons learned from the same work scope EBI performed at Quad Cities Unit 2 the year prior allowed EBI to plan for foreseeable hurdles and make necessary adjustments to address them prior to commencing the project at Unit 1.
|Proper FME procedures are of the utmost importance when working on IPBD. All remaining photos courtesy of Electrical Builders, Inc.|
One of the lesson learned from Quad Cities Unit 2 that was applied to the planning stage for Unit 1 involved Foreign Material Exclusion (FME) procedures. During EBI’s work at Unit 2, FME proved to be a challenge due to pressures and currents inside the buildings. EBI referenced this issue when they developed the new FME plan specifically for the Quad Cities Unit 1 project. This included the redesign of EBI’s FME pillows to feature durable Teflon covers.
“Historically, FME covers used within the industry have failed to effectively form positive seals on the conductor, resulting in fires and dangerous situations for workers,” said Brian Warzecha, EBI Safety Coordinator/Procurement Specialist. “This safety issue is what led EBI to develop their own proprietary FME covers, which have proven to be a great success.”
During the Project
Every day at 5:30 a.m., the EBI team and Quad Cities management met to go over schedule status and discuss issues that might arise throughout the day. The replacement process included the complete removal of the existing IPBD system, support steel, and air handling system. The EBI team also reinstalled the subsequent replacement modifications for the new IPBD system to include post installation testing. A comprehensive internal video inspection of the entire system and a final Hi Pot were conducted prior to closing the project.
|All welding contractors are not the same. IPBD installation experience and continuity specific to IPBD is required for proper installation.|
Free release of IPBD material that required removal proved to be a timeline challenge. Sections of removed IPBD and support steel needed to be staged in safe configuration for Radiation (RAD) Protection Personnel to manually scan each item prior to sending them through the building wall penetrations and to the EBI crew outside. Due to the limited workspace that was available, the process of staging and waiting for RAD Protection to complete their scanning incapacitated the demolition crew. As a result, EBI’s crew moved to other locations where they could work so the workers’ safety was not compromised. This situation was less than ideal and became another lesson learned. On EBI’s next project, there will be two RAD Techs that will directly report to EBI on each shift in order to work in tandem with them as they go.
|Accurate engineering combined with proper layout and prep work are prudent for a quality IPBD installation.|
The limited workspace also created another challenge, which was the removal of IPBD sections during demolition. EBI’s expertise was called upon to develop a unique solution to help maneuver moving obstacles, resulting in easier removal of IPBD sections.
Throughout the entire project, EBI identified and utilized effective time management techniques such as storing all materials in their trailers until needed allowing for no double-handling of items. Exelon’s project management team was very supportive of EBI’s suggestions and the result speaks for itself in the completed project.
Results and Lessons Learned
The Quad Cities Unit 1 project was completed with zero OSHA recordable incidents, and 43.5 hours ahead of the 21 day schedule. EBI’s improved FME procedures and new pillow design allowed for no rework of the IPBD and zero FME found during the internal video inspection.
|Pre-planning meetings between EBI, engineering, and Exelon began six months prior to the project start.|
Brian Wahlheim, Exelon’s Project Manager, noted the effectiveness of EBI’s FME procedures, “In addition to a quality job well done, the improvement in the FME practices and procedure adherence was noticed not only by my project team but also by station management.”
As a result of the successful project completion of Quad Cities Units 1 and 2, and also at Exelon’s sister plant, Dresden Nuclear Unit 2, EBI has been awarded Dresden Unit 3 IPBD change-out this fall where the new challenge will be a timeline window shortened to only 17 days. This challenging timeline is driven by plant refueling outage rather than other major equipment change-out, which would allow for more time. EBI has also signed onto additional scope at Dresden Unit 3 (i.e. the GSU LU terminal cabinet) which will allow for a smoother removal and installation transition from the IPBD to the GSU transformer.
Keys to Success
Exelon was open to suggestions made by the EBI project team. This was a substantial benefit to the flow of the project. Exelon project management took into consideration that EBI is the category expert for IPBD installation and they tapped into the experience and knowledge that EBI brings to the table. Through lessons learned, EBI has refined processes and procedures, allowing them to identify potential project pitfalls and avoid costly lost time. Concise and consistent communication is the key to project success.
Electrical Builders Inc. (EBI) is a high power conductor service provider. An active member of the International Brotherhood of Electrical Workers (IBEW) and the American Nuclear Society (ANS), EBI has provided quality workmanship to power plants and utilities since 1974. Learn more by calling 877-297-0616 or at www.electricalbuilders.com.More Power Engineering Issue Articles
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