The hot section of a gas turbine engine operates under extreme temperatures and pressures, making it the most critical area for inspection and maintenance.
Inspection Procedures
- Combustor Liner Inspection: Check for thermal barrier coating spallation, cracking, and distortion
- Turbine Blade Inspection: Examine for creep, oxidation, foreign object damage, and tip rubbing
- Nozzle Guide Vane Inspection: Verify cooling hole integrity and trailing edge condition
- Seal and Damper Inspection: Assess wear on inter-stage seals and vibration dampers
NDT Methods
Fluorescent penetrant inspection (FPI), eddy current testing, and computed radiography are the primary NDT methods used for hot section components. Borescope inspection provides visual access without engine disassembly.
Life Limits and Retirement
Each hot section component has a certified life limit expressed in cycles or hours. Adherence to these limits is mandatory under FAA and EASA regulations.