Rules for selecting vibration isolators

Machines and equipment used in industry, manufacturing, and construction can generate significant mechanical vibrations that disrupt their proper operation, accelerate equipment wear, and emit excessive noise.

Vibration isolation is crucial for protecting equipment, maintaining operational efficiency, ensuring safety, and reducing noise. Excessive vibrations can lead to component damage, failures, and costly repairs. Investing in proper vibration isolation solutions is essential.

At Power Rubber, we offer high-quality vibration isolators - an effective solution that prevents the transmission of vibrations to floors, walls, and other machines. They protect machinery, prevent structural damage, help maintain structural integrity, and minimize undesirable sounds.

What are vibrations?

Vibration is a type of mechanical motion in which an object oscillates around a point of equilibrium. It is characterized by frequency, amplitude, and energy. Vibrations can be caused by natural phenomena (earthquakes, wind, ocean waves) as well as artificial ones resulting from mechanical movements of machines or tools used by humans, which generate vibrations.

Industrial machines produce prolonged vibrations that affect equipment lifespan, generate unwanted noise, and impact the structural integrity of nearby buildings. To reduce vibration intensity, a low frequency of the system's natural vibrations is required. To achieve this, the use of rubber dampers is necessary.

Impact of vibrations on equipment performance

Uncontrolled vibrations can disrupt machine operation and generate excessive noise. Vibrations cause serious damage to mechanical systems, operational issues, reduced equipment lifespan, and have a negative impact on operational efficiency, reliability, safety, and employee comfort.

What are vibration isolators and what are they used for?

Effective vibration control is essential for reliable and safe machine operation in industrial environments. Vibration isolators are designed to effectively isolate vibrations generated during machine operation. They are placed between the equipment and the surface. The proper vibration isolator minimizes or completely absorbs and dampens the energy of vibrations transmitted to the surface.

Why is vibration isolation so important?

Operating machines and equipment are often exposed to high-frequency vibrations. Vibrations and shocks have a negative impact on human health, reduce equipment lifespan, and cause damage to structures or entire buildings.

The selection of appropriate vibration isolators brings several benefits, here are some of them:

• optimal vibration and noise control, including structural noise
• mitigation of the impact of excessive noise and vibrations on workers' health (quieter and more comfortable work environment)
• improvement of working conditions and quality
• protection of equipment from excessive wear
• reduction in the number of failures, minimizing repair and maintenance costs
• energy efficiency and improved operational performance

Selection of vibration isolators for machines and equipment

Below are the key principles to consider when selecting the appropriate rubber dampers:

Determination of the total mass of the device and the maximum load on the vibration isolator

The machine's mass directly affects the type and size of the vibration isolator. Each vibration isolator has a specified maximum load range at which it maintains optimal vibration isolation effectiveness. Knowing the total mass of the machine allows for the even distribution of the correct number of dampers at various points of the device. The number of vibration isolators depends on the mass and construction. The greater the total mass, the larger the mountings must be or the greater their number needed to reduce machine vibrations. It is essential not to overload any of the elements, as this can lead to a loss of isolation effectiveness and faster wear.

Vibration characteristics

The frequency of forcing vibrations and the resonant frequency are key parameters when selecting vibration isolators.

• Forcing vibration frequency - the frequency at which the device generates vibrations (e.g., motor's rotational speed)
• Resonant frequency - should be significantly lower than the forcing frequency to avoid vibration amplification

The ratio of the frequency of the force causing the device's vibrations to the natural frequency of the isolator directly affects the effectiveness of vibration isolation.

Dynamic loads and number of cycles

In machines where periodically varying forces occur (e.g., presses, compressors), in addition to static mass, dynamic forces must be considered. Rubber shock absorbers should be matched to the machine's mass and the frequency of vibrations it generates during operation. The number of cycles per minute determines the frequency of vibrations that need to be effectively dampened. If the machine's vibration frequency approaches the isolator's natural frequency, resonance can occur, leading to uncontrolled vibration amplification instead of damping. Therefore, knowledge of the operating frequency allows for the selection of the appropriate type of vibration isolator.

Static load

Static load is one of the key parameters to consider when choosing a vibration isolator. It must be matched to the device's mass and the distribution of the load on the number of support points. Static deflection is the extent to which the vibration-damping clamping element is compressed under the weight of the machine. The greater the static deflection, the greater the load it carries. Exceeding the static load can lead to permanent deformations, and even damage to the element.

Working conditions

The environment in which the machine operates is crucial when choosing an isolator. Choosing a single vibration isolator based on temperature variations is crucial for effective vibration damping and longevity. It is essential to know the temperature range to which the system will be exposed. Working at too high a temperature can cause rubber degradation, leading to a loss of damping properties. In low temperatures, elastomers harden, limiting their flexibility.

To properly select a vibration isolator, it is necessary to check if the material from which it is made is suitable for the specific chemical working environment.
 

Principles of selecting vibration isolators - what else to consider?

The proper selection of vibration isolators (vibration-damping elements) aims to choose the appropriate components to limit the transmission of vibrations to the building structure or device. As mentioned earlier, the task of vibration isolators is effective isolation from vibrations that can affect the durability and lifespan of machine components and the safety of use. This is particularly important in the case of rotating machines (e.g., fans), where vibrations occur with a high frequency expressed in Hz or rotations per minute (RPM).

In the earlier part of the article, we highlighted a crucial issue, namely: comparing the natural vibration frequencies of the system with the forcing vibration frequencies. Here we want to emphasize that effective vibration isolation requires the natural vibration frequency of the system to be at least 1.4 times lower than the forcing vibrations. This is crucial in ensuring the right level of vibration isolation without affecting the rest of the system's operation.

The installation method is also crucial here. Vibration isolators must be mounted symmetrically relative to the center of gravity and evenly tightened. The mounting point, i.e., the distance from the vibration axis, is extremely important. In the case of uneven surfaces, self-leveling vibration isolators are used (they have an adjustment screw with a nut), which adapt to the slope of the surface.

There are many models of vibration isolators available on the market (with non-through threaded holes, on a metal plate with mounting holes, equipped with elastic elements with a built-in thread or sleeve, etc.). Rubber dampers for food contact should be made of materials approved for such conditions.

In summary, when selecting vibration isolators, the main factors to consider are the device's mass, vibration characteristics, required damping degree, and working conditions. The mounting method, type of fastening, and hole arrangement in the base should also be taken into account.
 

High-quality vibration isolators available at Power Rubber store

At Power Rubber store, we offer a wide range of vibration isolators tailored to various machines and working conditions. Our products effectively isolate vibrations, preventing damage to vibration-sensitive machinery and equipment. This translates into lower maintenance costs and reduced downtime.

Why buy vibration isolators at Power Rubber?

Vibration isolators from Power Rubber provide stability and durability, even in challenging conditions. They significantly improve operational efficiency, reduce energy consumption, mitigate noises and annoying sounds in industrial and residential environments.

With our experience and industry knowledge, we offer professional support in selecting the right vibration isolators. By leveraging the expertise of our professionals, you can be confident that the purchased rubber damper will create a more pleasant work environment and enhance employee safety, while allowing machines to operate more efficiently.

Choose the right vibration isolator for a specific machine (milling machines, presses, planers, air conditioners) without displacements, clearances, or secondary vibrations. Feel free to contact us at: +48 22 292 40 24 or +48 505 16 03 03, via email (power|powerrubber.com| |Power|PowerRubber.com), or through our contact form.