Rotors of rotating machines, including gas turbine units, are extremely sensitive to misalignment. Regular maintenance and laser alignment during commissioning work in the long term significantly reduces costs for regular technical maintenance.

To access the compressor rotor, compressor blades, and bearing assemblies, it is necessary to remove the GTU casings. Before their removal, the GTU structure must be properly supported by mechanical jacks to avoid twisting the casing.

Major overhaul includes a complete inspection of the hot gas path with replacement of all necessary components: working blades, nozzle assemblies, combustion chamber elements, and fuel system.

During Major overhaul, the compressor assembly is subjected to careful inspections. The compressor inlet is checked for erosion, corrosion, and mechanical damage. The rotor is also checked for cracks and other damage, and the bearing inserts are checked for wear.