Circular Absorptive Sound Attenuators

TYPE SAC2 - 100


Circular Sound Attenuators are used in ventilation systems and are specifically designed to reduce duct born noise. Concerning noise sources such as axial fans, compressors, generators or any other type, these attenuators are highly recommended to reduce the generated noise. The attenuators can be made in different materials and as a flange or spigot type, making it accessible for installation in a variety of situations and are recommended for use in corrosive conditions as industrial and offshore atmospheres. The SAC2 - 100 type is used as both primary and secondary attenuator, and can be made in large dimensions. Special consideration is given to the design of all units which are to be used in environments of high humidity, pollution or high temperatures. The design is optimized to attain a maximum insertion loss with a minimum pressure drop and may be used for pressures up to 20 bar.

Materials and dimensions:

The attenuator is normally constructed in stainless steel, and the standard sizes are shown in the brochure, but all attenuators are individually designed according to the customers' requirements and non-standard sizes can be delivered upon request. Acoustical centerpods can be incorporated in the design for improved noise reduction performance where the pod's diameter can be adjusted for optimal reduction.

Noise data:

The insulation material used consists of non-toxic and non-combustible mineral wool, and is firmly covered by polyester or glass fibre cloth and a perforated plate to prevent fibre migration from the wool. For the circular sound attenuators the noise data is based on:

  • ISO 7235- "Acoustic measurement procedure for ducted silencers - insertion loss, flow noise and total pressure loss."

The sound reduction achieved by a sound attenuator is heavily dependent on the sound field inside a duct, and is limited by the duct arrangement. This is why measurements on site will often vary from laboratory measurements, because the attenuator on site will be affected by factors as flanking noise, background noise, vibration etc. In order to get the best possible result, please contact Acoustics for accurate noise calculations for your particular need. For more information on self-generated noise for the circular sound attenuator, please contact Acoustics.