Packless Circular Attenuator
These in-line tubular packless (no acoustic fill) attenuators are available in two models for special applications requiring broad band noise reduction. Performance data is provided for three basic diameters – 8”, 12”, and 16”.
Model NF SDS-20 provides excellent attenuation values with a moderate pressure drop for system velocities at or near 1000 fpm.
Model NF SDS-8 is a low-pressure drop unit ideally suited for higher velocities at or near 2,000 fpm.
Special features of our Standard Attenuators are:
- No acoustic fill or other sound absorptive material
- 22 gauge minimum galvanized steel casings
- 24 gauge minimum perforated galvanized baffle
- Seams are mastic filled to insure airtight units to 8” w.g.
- Also available in SS or aluminium construction
Performance Data / Testing:
Acoustical performance ratings are based on tests conducted by Intertek Testing Services, formerly ETL Testing Laboratories, Inc., in accordance with ASTM E477 “Standard Method of Testing Duct Liner Materials and Prefabricated Silencers for Acoustical and Airflow Performance.”