What classification does the pump "vane pass rate" vibration fall under?

The classification of "vane pass rate" vibration as synchronous is based on the nature of the vibration linked to the cyclical passage of vanes through a pump. In centrifugal pumps, vanes rotate in a repetitive cycle, causing vibrations that occur at a frequency directly related to the rotation speed of the pump. This means that the vibrations will occur at a specific frequency, linked to the rotational speed, which aligns with the definition of synchronous vibrations.

Synchronous vibrations are typically understood as vibrations that occur at the same frequency as the source of excitation. Since the pump's vanes pass the pressure points at a consistent rate determined by the rotation speed, the vibration observed is synchronous with this speed.

This understanding helps differentiate it from other categories. Non-synchronous vibrations occur at frequencies that are not directly tied to the source's rotation rate, while sub-synchronous vibrations happen at frequencies lower than the rotational frequency. Random vibrations do not have a consistent frequency and are often a result of complex interactions and turbulence. Each of these classifications describe different behaviors that help in diagnosing and analyzing machinery performance and health.