A common source of noise in the building comes from the vibration of objects and machines mounted on the floor or wall. Common examples of the source of vibration are motors, pumps, fans, compressors, or other machines that produce abnormal vibration by electrical supply frequency or the rotation motion of the machine during normal uses. Vibration can transmit for a long distance throughout the building structure and a high level of vibration can even cause the failure of machinery or severe sound pollution to the environment.
In order to prevent damage caused by unwanted vibration, the installation of a vibration isolator is a cost-effective solution for many industries. The purpose of vibration isolation is to control the vibration within acceptable levels and avoid adverse effects on certain objects. It works in the situation where the unwanted vibration comes from the equipment and isolation is required to reduce the vibration transmitted from the equipment to the support structure such as a facility floor. It can also work conversely when the vibration-sensitive machines require isolation from unwanted vibration. The vibration-sensitive machines include surgical microscopes, lasers, computer disk drives, electronic equipment, etc. The isolation of vibration-sensitive machines can reduce the transmission of vibration from the structure to the machine. Right vibration isolation can protect sensitive machinery, provide extra safety when operating the machine, and reduce the sound caused by vibrating machines.
There are two types of vibration isolation methods which are passive vibration isolation and active vibration isolation.
1. Passive Vibration Isolation
Passive vibration isolation is the most basic method of vibration isolation that uses passive techniques such as mechanical spring or rubber pads mounted on the vibrating machines or equipment. It involves damping elements and mass-spring that move as a harmonic oscillator to cause energy dissipation and affect the natural frequency.
2. Active Vibration Isolation
The active vibration isolation system involves several components such as a controller, piezoelectric accelerometer, electromagnetic transducer, and feedback circuit. The accelerometer is attached to the table and able to detect the vibration. The acceleration signal is handled and processed by the control circuit and amplifier. The controller analyses the amplitude and frequency of the vibration and provides a feedback signal. The electromagnetic transducer received the feedback signal and then produces a force canceling the vibration. The feedback system provides a better level of vibration isolation when compared to normal damping.
Types of Vibration Isolator
The isolation can be achieved by using special mounts to absorb the vibration from the equipment or machinery. The materials for vibration absorbers are normally made of rubber or dense foam as they are good at absorbing unwanted movement of the machine and allow the machine to operate more efficiently and quietly. The special vibration mounts can be customized in size, shape, and thickness to fit perfectly to the equipment. They are easy to install and will not affect the operation of the machine or equipment.
1. Spring Vibration Isolator
Sprint vibration isolators are made of steel and are commonly used for heavy-duty applications as they can handle machinery with a weight of around hundreds of tons. They are popular to be used when the static compression is greater than 5cm or where the conditions of the environment do not allow the use of rubble or other materials. The applications of spring vibration isolators range from fans in HVAC equipment to engine generator sets. In conclusion, steel spring vibration isolators are able to handle large static compression, low natural frequency, and have high resistance to corrosion by water, solvents, and oil. However, the damping ratio is very small which is around 0.005 only, so the transmission rate is very large at resonance. They are also easy to transmit vibration at high frequency along the steel wire and produce rocking motion.
2. Rubber Vibration Isolator
A good rubber vibration isolator provides high noise reduction capabilities, long service life, stable performance, and strong adhesion to metal. Their bearing capacity is large and suitable to be used for handling compressing, cutting, and cutting pressure. Rubber vibration isolators can be customized into different shapes and stiffness. They possess a higher internal damping effect than steel springs. The disadvantages of natural rubber vibration isolators are they have a greater creep under heavy load, cannot be contacted with oils, ozone, or hydrocarbons, only suitable for places with high equipment and under ambient temperature. Other types of rubber can be used to overcome these issues in certain circumstances. For example, nitrile rubber and neoprene rubber isolators have good resistance to ozone and hydrocarbons. Silicone rubber isolators can be used at lower and higher temperatures. Nitrile rubber isolators also can handle high-temperature environments.
3. Metal Rubber Vibration Isolator
The metal rubber vibration isolator is made of metal wire and is a simulation product of the natural rubber. Although it does not contain any natural rubber, still able to provide the same level of elasticity and porosity as natural rubber. Metal rubber vibration isolators have a long service life, good damping characteristics, the ability to work under high pressure, extreme temperature, and high vacuum environments. In this case, they are used for the industries that require special requirements such as aerospace, aviation, and the chemical industry.
Unwanted vibration may damage the machines and affect the efficiency level of operation which can cause production losses. Good control of the vibration can prolong the machinery’s service life and reduction of noise pollution can create a pleasant working environment for the workers. You should choose the vibration isolator based on the ambient temperature, the weight that the isolator needs to support, the natural frequency of the object vibrates, and the ratio of the vibration that enters and leaves the object. MecHero Malaysia supplies different types of vibration isolators for a wide range of industries. You can always contact us at +6011-7000 7687 or email us at firstname.lastname@example.org for an inquiry about vibration isolation solutions in Malaysia. As a steel and online hardware store in Malaysia, we also supply a wide range of steel materials, general hardware, or mechanical components. Tell us your requirements now and we can advise you accordingly.
Photo credit: antivibration-systems, techmfg, indiamart, thevmcgroup, masonwest