General Information
Application
- Circular silencer for the reduction of noise in circular ducts of ventilation and air conditioning systems
- For the reduction of fan noise
- Can be used as cross talk silencer to reduce the transfer of noise through ducts between neighbouring rooms
Special characteristics
- Insertion loss measured according to ISO 7235
- Choice of 2 splitter widths for each nominal diameter
- Increased insertion loss with a wider splitter
- Reduced differential pressure with a smaller splitter
- The sound absorbing material is non-combustible
- Insulation thickness 2 in or 4 in
- Leakage class D for nominal sizes up to and including 16 in
- Leakage class C from nominal size 18 in
Nominal sizes
- ØD: 10, 12, 16, 18, 20, 22, 25, 28, 31, 35, 39 in
- L: 20, 39, 59 in
Variants
Insulation thickness
- 050: Circular silencer with 2 in insulation
- 100: Circular silencer with 4 in insulation
Splitter width
- T: 2, 4, 6, 8, 10, 12 in
Construction
Circular silencers
- No entry: galvanised steel 1.0917
- A2: Stainless steel 1.4301
Type of connection
- No entry: Spigot with groove on both ends
- D2: Spigot with lip seal on both ends
- AS: Spigot with lip seal and socket-type spigot on one end
Parts and characteristics
- Circular casing
- Perforated inner duct
- Splitter
- Sound absorbing material
Construction features
- Circular casing
- Outer duct: spiral duct, galvanised steel 1.0917
- Outer duct: plain duct, stainless steel 1.4301
- Splitter
- Aerodynamic shape, galvanised steel 1.0917 or stainless steel 1.4301
- Spigot suitable for circular ducts to EN 1506 or EN 13180
- Lip seals up to nominal size 31
- Max. operating pressure 8 in w.g.
- Max. airflow velocity 3937 fpm
- Max. operating temperature 194 °F
Material and surfaces
- Splitter made of galvanised sheet steel 1.0917 or stainless steel 1.4301
- Casing pipe as spiral duct made of galvanised steel 1.0917
- Smooth casing pipe made of stainless steel 1.4301
- Perforated inner duct made of galvanised steel 1.0917 or stainless steel 1.4301
- Spigot made of galvanised steel 1.0917 or stainless steel 1.4301
- Absorption material is mineral wool
- To EN 13501, fire rating class A1, non-combustible
- Non-hazardous to health according to the German TRGS 905 (Technical Rules for Hazardous Substances) and EU directive 97/69/EC
- Protection against erosion from airflow velocities up to 3937 fpm
- Inner duct with non-woven fibre (fleece)
- Splitters faced with glass fibre scrim
- Inert to fungal and bacterial growth according to EN 846
Standards and guidelines
- Insertion loss and sound power of air-regenerated noise tested according to ISO 7235
- Meets the hygiene requirements of VDI 6022, VDI 3803 Part 1 and DIN 1946 Part 4
- EC Directive 2014/34/EC (ATEX): Equipment and protective systems intended for use in areas with potentially explosive atmospheres
- EC Directive 1999/92/EC (ATEX): Improvement of the safety and health protection of workers potentially at risk from explosive atmospheres
- Leakage class according to DIN EN 15727
Maintenance
- Low-maintenance as construction and materials are not subject to wear
