What Is Vibration Analysis?
Vibration analysis is defined as a process for measuring the vibration levels and frequencies of machinery and then using that information to analyse how healthy the machines and their components are. While the inner-workings and formulas used to calculate various forms of vibration can get complicated, it all starts with using an accelerometer to measure vibration. Anytime a piece of machinery is running, it is making vibrations. An accelerometer attached to the machine generates a voltage signal that corresponds to the amount of vibration and the frequency of vibration the machine is producing, usually how many times per second or minute the vibration occurs.
All data collected from the accelerometer goes directly into a data collector (software), which records the signal as either amplitude vs. time (known as time waveform), amplitude vs. frequency (known as fast Fourier transform), or both. All of this data is analysed by computer program algorithms, which in turn is analysed by engineers or trained vibration analysts to determine the health of the machine and identify possible impending problems like looseness, unbalance, misalignment, lubrication issues and more. Vibration analysis can detect problems such as:
- Bearing failures
- Mechanical looseness
- Resonance and natural frequencies
- Electrical motor faults
- Bent shafts
- Gearbox failures
- Empty space or bubbles (cavitation) in pumps
- Critical speeds
Vibration Analysis Tools and Technology
Advanced technology, particularly advances in wireless technology, has greatly improved how vibration analysts collect, interpret and share data. Today, vibration analysers are extremely portable, communicate with smartphones and tablets in real time, and can generate FFT in extremely high resolution. Many vibration instrument companies develop their own apps to communicate with each other.
Another form of advanced technology you’ll see with vibration analysis interpretation instruments is operating deflection shapes (ODS) 3D simulations of machinery vibrations. In a nutshell, this type of software exaggerates vibration-induced movements in a 3D model so you can visualize the forces impacting your machine while it’s running.
Some vibration analysis instrument companies offer databases with thousands of bearing fault frequencies preloaded to help you identify certain fault frequencies for your bearings. Some software can continuously monitor the geometry of your rolling elements and warn you when possible premature failures may occur.
As with most advanced technology, the majority of vibration analysis data is automatically uploaded to the cloud and is available on your mobile device, computer or directly from your browser. This is especially useful if you’re performing vibration analysis as a third-party consultant, so you can freely share spectra with your clients.
Benefits of Continuous Vibration Monitoring
The methods and tools discussed in this article not only are great for determining what’s wrong with a piece of equipment or machinery (reactive), but they also can be used to catch issues before they cause significant downtime (proactive). Using vibration analysis and monitoring enables you to look quantitatively into structural weakness or looseness, rotating component looseness and whether resonance is present.
If implemented properly, continuous vibration monitoring helps you optimize machinery performance. With the use of modern technology, you can take continuous vibration readings on various equipment in real time and have the data sent directly to your smartphone, tablet or desktop via the cloud.