Method for HTGR spherical fuel element nondestructive testing based on dynamic measurements of their efficiency in a critical assembly

The results of determining the content of fissionable material, absorbers and graphite in HTGR spherical fuel elements by the method based on measurements of reactivity changes, arising when spherical fuel elements, absorbing elements and elements without fuel pass through a critical assembly are given. The experiments were performed in the Astra critical uranium-graphite assembly. The investigation results and analysis of foreign experience indicate the possibility of testing the spherical fuel elements in a critical assembly equipped with a microcomputer-based automated measuring system, with required accuracy and fast response