Automatic System for Measuring the Zirconium Liner and Zircaloy-2 Thickness of Zirconium Liner Tubes

An automatic system to measure the zirconium liner thickness and Zircaloy-2 thickness of Zircaloy tubes with a zirconium liner for nuclear reactors has been developed. This system uses an electromagnetic probe connected to a data processing unit for measuring the liner thickness, an ultrasonic inspection system for measuring the wall-thickness, and a computer for calculating the Zircaloy-2 thickness from the liner thickness and wall-thickness. Fully automatic measurements on zirconium liner thickness and Zircaloy-2 thickness are performed with high accuracy to an order of 2μm. This newly developed system is very useful in assuring the liner layer and Zircaloy-2 thickness in the production of high-quality cladding tubes.