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Application

Sound attenuation.

Description

Circular duct sound attenuators.


Features and benefits:

  • Made to order.
  • Constructed in accordance with DW 144 specification for medium pressure (Class B) ductwork as standard. Class C construction also available.
  • Airflow can be in either direction.
  • Fitted with male spigots with integral seals.
  • Sound absorbent infill is encapsulated with glass cloth and perforated steel.
  • Central pods (type PLP) have aerodynamic fairings at each end.
  • Excessively large or heavy attenuators may be manufactured in mating sections for ease of handling.
  • Note that attenuators are supplied without support steelwork, brackets, fixings, gasket, mastic or other such items unless specified otherwise.
  • Part of a range of duct attenuators; other models specified separately.

General information

Color

Silver

Other

Guidance for specification option:

Protective paint finish (optional; visible external metal surfaces only).

Finish

Galvanized

Natural

Painted

Guidance for specification option:

Protective paint finish (optional; visible external metal surfaces).

Material

Steel

Stainless steel

Shape

Circle

Length

600 mm

900 mm

1200 mm

1500 mm

1800 mm

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Width

100 mm

125 mm

150 mm

160 mm

180 mm

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Height

Bespoke

Guidance for specification option:

Any width >99 mm

Uniclass

Pr_65_67_78_12 Circular attenuatorsPrimary

CAWS

U90/480 Silencers

U90/480 Silencers

Specification data - Circular attenuators

Application

Manufacturer's standard.

High-temperature (H1).

Guidance for specification option:

Two hour/ 300°C.

High-pressure (C).

Guidance for specification option:

DW 144, class C.

Special construction.

Guidance for specification option:

Consult manufacturer for options and insert requirements (including all relevant properties below).

Refer to equipment schedule for details.

Manufacturer guidance

Airflow can be in either direction.

Performance standards

To ISO 7235.

Duty

-

Insertion loss

Manufacturer's standard.

Guidance for specification option:

Derived from tests carried out in accordance with ISO 7235 and may vary depending on installed conditions.

Consult manufacturer for further details.

Air volume

Guidance for specification option:

Consult manufacturer for details based on dimensions specified, or insert requirements and consult manufacturer for size(s) required to achieve this.

Permissible pressure loss

Manufacturer's standard.

Guidance for specification option:

Derived from tests carried out in accordance with ISO 7235 and may vary depending on installed conditions.

Consult manufacturer for further details.

Casing material

Pre-galvanized steel, standard.

Grade 316 stainless steel, standard.

Lining material

Sound-absorbent infill encapsulated with glass cloth and plain/ perforated steel..

Duct connections

Guidance for specification option:

Insert requirements or omit. Ass Accessories for related options.

Markings

Guidance for specification option:

Consult manufacturer for options and insert requirements, or omit.

Configuration

Without pod (model PL).

With pod (model PLP).

Length

600 mm.

Guidance for specification option:

Standard.

900 mm.

Guidance for specification option:

Standard.

1200 mm.

Guidance for specification option:

Standard.

1500 mm.

Guidance for specification option:

Standard.

1800 mm.

Guidance for specification option:

Standard.

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Manufacturer guidance

Nominal casing length, excluding spigots.

Excessively large or heavy attenuators may be manufactured in mating sections for ease of handling.

Diameter

100 mm.

Guidance for specification option:

Nominal diameter.

Outer diameter: 210 mm.

125 mm.

Guidance for specification option:

Nominal diameter.

Outer diameter: 235 mm.

150 mm.

Guidance for specification option:

Nominal diameter.

Outer diameter: 260 mm.

160 mm.

Guidance for specification option:

Nominal diameter.

Outer diameter: 270 mm.

180 mm.

Guidance for specification option:

Nominal diameter.

Outer diameter: 290 mm.

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Manufacturer guidance

Excessively large or heavy attenuators may be manufactured in mating sections for ease of handling.

Manufacturing dimensional tolerance <1.0%.

Flanges

40 mm long circular spigot connections.

Noise

Manufacturer's standard.

Guidance for specification option:

Flow noise derived from tests carried out in accordance with ISO 7235 and may vary depending on installed conditions.

Consult manufacturer for further details.

Accessories

None.

Protective paint finish (visible external metal surfaces).

Guidance for specification option:

Insert colour requirements.

Melinex encapsulated infill.

Other.

Guidance for specification option:

Supplied without support steelwork, brackets, fixings, gasket, mastic or other such items unless stated otherwise.