MYTH: “1x RPM is always caused by unbalance.”
TRUTH: Unbalance always causes vibration at 1x RPM. However, 1 x RPM is not always caused by unbalance. Many other problems can exhibit vibration at this frequency. Examples are Misalignment, Bent shaft, bowed shaft, cracked shaft, eccentricity, open rotor bars in the motor, rubs, looseness, belt issues, and resonance.
MYTH: “The run time and lifetime of the equipment can be extended by performing a balance job on the equipment.”
TRUTH: Problems such as misalignment, bad bearings, looseness, etc cannot be corrected by balancing the machine. It is almost impossible to correctly balance a machine that has other defects affecting its performance. Misalignment, bad bearings looseness, etc should be corrected before attempting to balance equipment.