IBDs are periodically damaged in use when debris such as stones or birds are drawn into the engine. Often times the damaged blades can be repaired by grinding away the damaged material in a process called blending. However, if the size of a blend exceeds the manufacturer’s limits, then the IBD is retired from service.
The blend limits set by engine manufacturers are common to all blades and all IBDs of a given design. This one-size-fits-all approach forces the manufacturer to set limits that are based on the worst case scenario for blade vibration. Yet not all blades vibrate equally. Within a given IBD, some blades may vibrate strongly in an engine, while others barely at all. This results in blend limits that are at times overly conservative for a particular blade.
SmartBlend measures and analyzes each IBD and uses that data to tailor blend limits to a specific damaged blade. SmartBlend uses three of BDC’s unique technologies: EzVIBES® advanced vibration measurement system, EzID™ to determine the unique vibration characteristics, and FMM Predictor™ to simulate how that IBD will vibrate in an engine. Together, these tools provide the information needed to gauge if the IBD can safely be blended beyond the standard limits.
SmartBlend is now being used by the U.S. Air Force to:
- Evaluate damaged IBDs to return previously unserviceable IBDs to the fleet.
- Evaluate current blend limits and tech data to update data or expand limits that would allow serviceable parts to return to service.
- Confirm if repairs have raised high cycle fatigue risk factors.
- Provide root cause analyses to manage fleet HCF risk factors.
- Collect the data required to understand the unique Vibratory DNA of each part and help determine the useful life of each IBD.