Major Component Replacement
Life extension, uprates and major maintenance require the handling of major components within the plants. To perform this work during planned outages, a thorough knowledge of both major construction techniques, as well as the demanding requirements of nuclear protocol are required. Barnhart has developed unique tools and methods to perform the movement of major equipment such as:
RPV Closure Heads Steam Generators Pressurizers
Feedwater Heaters Condensers Transformers
This experience offers operators the peace of mind knowing that Barnhart will meet and exceed expectations for schedule, safety and ALARA. Clients can be certain they have chosen a company that knows the way through the nuclear environment.
Case Study - Entergy ANO Condenser Replacement
Entergy selected Barnhart as the rigging and transport contractor to support the replacement of the condenser tubes for the Units 1 & 2 steam turbine at Arkansas Nuclear One. The condensers were originally assembled in place without consideration of replacement. As such the only available access to the unit in the basement was through a wall adjacent to the main transformer yard that would remain energized for backfeed during the outage. Additionally, the replacement condenser tubes would be assembled into modules to speed the replacement.
Barnhart's use of innovative equipment and techniques created significant reduction in the critical path schedule. After nine months of planning, scheduling and equipment development, Barnhart successfully removed and replaced the tube bundles and water boxes of two condensers in less than 51 hours. The original expectation of the plant outage team was eight days or 192 hours.
We had a high degree of confidence in Barnhart from the start because of the depth and breadth of Barnharts equipment and expertise. Their management has a real professional knowledge of how to work in a nuclear site, preventing the logistics and technical aspects of moving the transformer from becoming a problem.
The tools developed for this project were not only unique in the requirement of handling the 100 ton components, but the tools themselves required innovations in assembly methodology due to the constraints of the site.
The handling of the ten major condenser modules was completed by the Barnhart team in just over two days without incident, saving Entergy almost six days above the original estimate.