Integrated quality control of the rotor discs of gas turbines of gas-compressor units by eddy-current and dye penetrant nondestructive testing

Abstract

The features of the integrated diagnostics of the discs of gas turbines of gas-compressor units using eddy-current and dye-penetrant testing are considered. The effectiveness of the detection of the crack-type defects in HPT and LPT discs under the first tooth of the fir-tree slots of the discs along the contact line of the teeth of the comb and blade butt are demonstrated. The calculations of the stress–strain state allowed the estimation of the occurrence of cracks in the fir-tree slots of discs, as well as the service life of discs up to crack formation at extraordinary operating temperatures. Integrated quality control by eddy-current and color capillary nondestructive testing provides reliable crack detection in details without serious costs for mechanical preparation of items for inspection along with a substantial reduction of the labor-intensiveness and depth of the inspection.