Workers with Entergy and Areva developed the gimbaled head solution to help improve inspection drives for both the CRDMs and the in-core instrumentation. A gimbaled head is a low-mass head-flexure assembly for reading and writing information scanned from nozzle volume to external hard drive. The challenge in developing the gimbaled head was threefold. The team needed to obtain a smaller transducer footprint while packaging the gimbal motion. They also needed the ability to retract the transducers when required while getting adequate couplant to the transducers. And they needed to reach all areas of interest.
With the implementation of the new process, the inspection time dropped from 150 hours to 92 hours for the CRDMs only. The overall outage time in 2009 fell from the baseline of 150 hours to 109 total hours for both CRDMs and ICI inspections using two of the delivery platform robots, SUMO-Rockys, simultaneously.