GE says repairing a CFM56-7BE high-pressure turbine blade can save 80% of the cost of buying a new one. That’s a big figure—but when you couple it with the fact that parts account for up to 70% of engine overhaul costs, this figure becomes even more striking.
Making the decision to save 80% could be easy for Boeing 737 next-gen engine operators, but the process to repair the CFM56-7BE HPT is complex. Lorna Hyman, GE’s marketing manager for material, walked me through the company’s advanced repair process for these HPT blades, which GE started offering late last year.
To appreciate what goes into repairing this blade in 21-28 days, watch the video below to see the before and after process.
In simplified terms, GE strips the coating while preserving the maximum amount of original blade material and then uses advanced technologies to inspect it.
After that, GE uses proprietary welding to repair cracks on the tip, inspects the blade to ensure the air holes are open, recoats the restored blade, then ensures optimized airflow around the part.
The tip length is very important because it has to fit tightly for peak engine performance. And even though fuel costs are still relatively low, no operator wants to pay more for fuel.
Hyman, who has been in GE’s repair business for 16 years—including serving as an engineering leader, says it typically takes 50-70 days to overhaul the whole engine.
GE spends $40 million per year on repair development.