In 2023 GES Tech Group, Inc. (GES) was contracted to design an IC engine driven skid with vibration isolation for an airport back-up power application. The skid was modeled in 3D using non-linear FEA, including determination of the resonance spectrum and forced vibration responses.
In 2025 one of the two identical units experienced a catastrophic coupling failure, as illustrated below. The coupling failure occurred in the presence of excessive vibration amplitudes that exceeded the original design parameters. Excessive vibration had not been previously reported by the owner and this abnormal condition was suspected of being the root cause of the coupling failure.
GES was contracted to conduct a forensic investigation to identify the root cause of the coupling failure and to recommend mitigation for the affected unit and the identical sister unit.
Investigations on site determined that the originally specified vibration isolation springs for both units had been installed in the fully compressed condition associated with shipping and had not been released when the units were commissioned. The unique vibration patterns associated with discrete hard points and a flexible skid were subsequently investigated by GES and documented.
It was ultimately determined that the failed coupling was caused by a severe drive line misalignment with no contribution from the excessive vibration experienced by both units for a two year period. All isolation springs were adjusted in accordance with GES recommendations and resulting vibration levels met specifications.
