Choice of energies in gamma-absorption method for layers thickness measuring of two-layers articles

Empirical formulae are offered to describe the correlation of optimal energies, minimizing average-weighted error in gamma-absorption measuring the thickness of the layers of two-layer pieces, with the thickness of each layer equal to 30-150 mm in terms of carbon. The approximation error of the information parameter with the use of tables does not exceed 10%, with the assessment error for the thickness of layers being not more than 2.5%. An equation was derived to select optimal energies with a sufficient accuracy (with the error not more than 6%).