Which measurement is most indicative of dynamic balance in rotating machinery?

Velocity is the most indicative measurement of dynamic balance in rotating machinery because it provides insight into the vibrational characteristics of the system during operation. In the context of vibration analysis, velocity is often preferred over other measurements because it reflects the energy present in the vibration and gives a clearer understanding of how the machine operates under dynamic conditions.

When assessing the balance of rotating machinery, velocity measurements can effectively indicate how well the machine is running at operational speeds. This is particularly useful because imbalances in the system can lead to increased vibration levels, and measuring velocity allows for a direct correlation between those vibrations and the potential for wear or damage.

Basing the assessment on velocity also aligns with standard practices in vibration analysis, where frequency components are analyzed in terms of velocity for identifying imbalances and other related issues. Other measurements, though they provide useful data, may not capture the dynamic interactions of the machine as thoroughly as velocity does. For instance, while RPM indicates the speed of rotation, it does not reflect the vibrational state; displacement provides a measure of movement from a reference point but doesn't convey the energy of the vibration itself, and acceleration may not accurately reflect machine behavior across varying speeds. Thus, velocity serves as a valuable diagnostic tool for evaluating dynamic balance in rotating machinery.