Vibration Isolation
Is vibration isolation your problem? Sorbothane has the answer.
Sorbothane is a proprietary, visco-elastic polymer – an ideal vibration isolation material. To learn more about how Sorbothane can help with your vibration isolation needs please feel free to contact us anytime.
What is vibration?
When we talk about vibration and vibration isolation we’re referring to mechanical oscillations about an equilibrium point and then isolating an object, such as a piece of machinery, from the source of the disruptive vibrations.
It’s common to deal with vibration isolation concerns in industrial, electronic, structural and ergonomic applications because it is undesirable. Vibration wastes energy and creates a lot of unwanted sound and noise that can be equally damaging. For example, the vibrational motions of engines, electric motors, or any mechanical device in operation are typically troublesome on many levels.
Such vibrations can be caused by imbalances in the rotating elements of the machine, uneven friction of the parts, the continuous meshing of gears, etc. Careful designs that include a vibration isolation solution usually minimize unwanted vibrations.
Types of vibration:
There are two common types of vibration. Free vibration and Forced Vibration.
Free vibration occurs when a mechanical system is set in motion with an initial input or push and then allowed to vibrate freely. An simple example of this type of vibration is when you pull a child back on a swing then let them go to swing freely. Snapping a rubber band is another example. This type of mechanical system will vibrate at one or more of its “natural frequencies” and damp down to zero.
Forced vibration is when an alternating force or continuous motion is applied to a mechanical system. Examples of this include a washing machine that is not running smoothly as designed (shaking violently) due to an imbalance, The cars and trucks that we use for transportation against the roads we drive on, or the violent shaking of a building during seismic activity.
Why do we need vibration isolation?
In a lightly damped system when the forcing frequency nears the natural frequency the amplitude of the vibration can get extremely high. This phenomenon is called resonance. It should be noted that the natural frequency of a system is often referred to as the resonant frequency.
Mechanical resonance is the tendency of a mechanical system to absorb more energy when the frequency of its oscillations matches the system’s natural frequency of vibration (its resonance frequency or resonant frequency) than it does at other frequencies. It may cause violent swaying motions and even catastrophic failure in improperly constructed structures including bridges, buildings, and airplanes a phenomenon known as resonance disaster.
If resonance occurs in a mechanical system it can be very harmful – leading to eventual failure of the system. Consequently, one of the major reasons for vibration analysis is to predict when this type of resonance may occur and then to determine what steps we can take to prevent it from occurring.
At the most basic level, vibration isolation is put in place to reduce the transmission of noise but the concerns are usually much greater.
Vibration Isolation:
Since vibrations can be irritating, damaging or possibly cause catastrophic disasters, vibration isolation systems are implemented.
Vibration isolation is the process of isolating an object, such as a piece of equipment, from the source of damaging vibrations. A good vibration isolator takes mechanical energy out of the system so it’s no longer a concern.
A good vibration isolator also lowers the natural frequency of a system to below the excitation (or disturbing) frequency. When we keep these two frequencies “out of sync” it will greatly reduce the problems of vibration. Sorbothane can absorb over 50% of the vibration energy over most of its temperature operating range at frequencies from 10 to 30,000 Hertz.
Some types of vibration isolation and why Sorbothane is superior:
Springs: Properly designed metal springs can be good isolators but have almost no damping ability. Sorbothane eliminates the need for metal springs.
Rubber: Rubber also has very little damping capability and can sometimes make things worse if not properly designed for a specific application.
Oil dampers: (dashpots) have good damping capability but no isolation capability.
Foam: Foam products can be good isolators but have limited life.
Polyurethane: Sorbothane is a thermoset, polyether-based, polyurethane material.
Sorbothane combines shock absorption, good memory, vibration isolation and vibration damping characteristics. While many materials exhibit one of these characteristics, Sorbothane combines all of them in a stable material with a long fatigue life.
For more information about Sorbothane’s Vibration Isolation Solutions please contact us anytime.