Anti-vibration mounts

Frequently asked questions — Anti-Vibration Mounts

• How do you choose between a rubber-metal mount and a helical spring mount?

  The choice mainly depends on the machine's excitation frequency. Rubber-metal mounts made of NBR or EPDM are suitable for common applications. However, for very low excitation frequencies, such as those encountered in compressors or large motors, rubber cannot achieve a sufficiently low natural frequency. In this case, helical spring mounts, offering a typical natural frequency of 4 to 8 Hz, are recommended to ensure proper isolation.
• What precautions should be taken to avoid amplifying vibrations instead of attenuating them?

  Effective isolation requires the natural frequency of the assembly to be lower than the excitation frequency divided by the square root of two. In practice, it is recommended to aim for a factor of 3 to 5 to achieve isolation greater than 80%. An incorrect calculation that does not take into account total mass, minimum excitation frequency, mass distribution and the number of support points carries a risk of resonance, which amplifies vibrations rather than reducing them.
• Which type of mount should be preferred for sensitive electronic equipment subjected to shocks?

  For sensitive electronic equipment, aerospace and military hardware, or transport-related applications, braided stainless steel wire rope suspensions are the appropriate solution. Unlike rubber-metal mounts, these suspensions are distinctive in their ability to absorb shocks and vibrations in all directions, providing the multidirectional protection required for this type of equipment exposed to complex mechanical environments.
• What solutions are available for environments with severe thermal or chemical constraints?

  For specific operating conditions, technological variants are available. Silicone mounts are recommended for applications subjected to very low or very high temperatures. If the environment presents risks of chemical degradation, anti-vibration mounts made of fluorinated elastomer should be used. These specific materials ensure the durability and the preservation of the mechanical properties of the elastic element when faced with the environmental constraints encountered.