A reactor in Sweden
was concerned about surface pitting around an inlet cooling water port.The 34
inch diameter port is under approximately 45 feet of water.The only access to
the port is through the ten inch annulus between the fuel shroud and reactor wall.The
customer wanted to monitor in the nozzle surface over several years to asses the surface damage caused by water chemistry.
Solution:
QUEST designed, fabricated and
installed a custom 2-axis scanning system and an underwater laser sensor that fit in the narrow annulus between the fuel shroud
and reactor wall.One axis of the scanner followed the lip of the port while
the other axis moved the sensor around the circumference of the nozzle.The system
was developed in a few months and combined custom sensors and fixturing with existing electronics and software.The data was analyzed using MATLAB (www.mathworks.com).The inspections were done
during scheduled outages.
