Research and Development > Focus of Research > Operation of Nuclear Units Support > Nuclear Fuel Inspections

Nuclear Fuel Inspections

Russian fueld assembly mock-up

The nuclear power plant Temelín is the only VVER type plant where it is possible to perform a fuel assembly repair. The fuel repair is performed during a reactor outage by means of Fuel Repair and Inspection Equipment (FRIE) and primarily by the fuel vendor. Using this equipment, not only can the fuel repair be done, but the inspection of the whole assembly or ultrasonic testing can also be performed. The Post-Irradiation Inspection Program (PIIP) is a part of these inspections and it serves for long-term monitoring of fuel assembly behaviour.

The role of CVR is to provide independent evaluation and monitoring of the overall fuel assembly design. These activities cover comprehensive visual inspections, and within this framework, detailed twist, bow and growth measurements are performed. FRIE also serves for oxide layer thickness measurements on fuel rods to monitor the influence of water chemistry on the corrosion of the fuel cladding and overall fuel assembly construction. The result is feedback to the fuel operator and the fuel vendor for proper operability of fuel assemblies in order to identify the root causes of leaking fuel.