What is Machine Vibration?
Most of us are familiar with vibration; a vibrating object moves to and fro, back and forth. A vibrating object oscillates.
We experience many examples of vibration in our daily lives. A pendulum set in motion vibrates. A plucked guitar string vibrates. Vehicles driven on rough terrain vibrate, and geological activity can cause massive vibrations in the form of earthquakes.
There are various ways we can tell that something is vibrating. We can touch a vibrating object and feel the vibration. We may also see the back-and-forth movement of a vibrating object. Sometimes vibration creates sounds that we can hear or heat that we can sense. To observe how vibration can create sound and heat, rub your feet back and forth on a carpet.
In industrial plants there is the kind of vibration we are concerned about: machine vibration.
What is machine vibration? Machine vibration is simply the back and forth movement of machines or machine components. Any component that moves back and forth or oscillates is vibrating.
Machine vibration can take various forms. A machine component may vibrate over large or small distances, quickly or slowly, and with or without perceptible sound or heat. Machine vibration can often be intentionally designed and so have a functional purpose. (Not all kinds of machine vibration are undesirable. For example, vibratory feeders, conveyors, hoppers, sieves, surface finishers and compactors are often used in industry.)
At other times machine vibration can be unintended and lead to machine damage. Most times machine vibration is unintended and undesirable. This article is about the monitoring of undesirable machine vibration.
Shown below are some examples of undesirable machine vibration.