ISO 9001 : 2008


SA B 30 Series

Type: Cylindrical
A – No Splitter; B – Single Splitter; C – Multiple Splitters
Construction: Galvanized Steel / Stainless Steel


BETEC CAD.’s manufactures square, rectangular, cylindrical and cross talk sound attenuators, which are used in commercial, industrial and residential buildings to reduce mechanical equipment noise transmitted through the ducted or un-ducted system achieving desired noise criteria in the occupied space. We design attenuators to achieve desired noise criteria in the occupied space or to reduce environmental noise for generator rooms, to meet
project requirements without compromising attenuator performance.

Economical results are obtained by using properly designed BETEC CAD. factory calibrated/fabricate Sound Attenuators.

Standard Construction


0.9 mm thick galvanized steel sheet.


0.7 mm / 0.9 mm thick Ø3 mm hole perforated galvanized steel sheet.


48 kg/m³ Density rockwool coverd with Black glass tissue.

Optional Fittings


Mild steel angles with red oxide or zinc coating, having Ø8 mm holes at a pitch of 250 mm. Alternate hole pitch available on customers request.

Optional Construction

Casing :

Thickness Up to 3 mm

Splitters :

0.9 mm thick Ø5 mm hole perforatedgalvanized steel sheet.

Casing and Splitter Material :

Stainless Steel (304/316L)


48 kg/m³ Density fiberglass wool covered with black glass tissue.


• BETEC CAD’s Sound Attenuator CS – B30 Series is of Cylindrical type. This Attenuator has been developed with special concern for both “on-fan” and “in-duct” situation and is suitable for use up to a maximum pressure of 1500 Pa.
• Central splitter is a conical inlet to minimize self generated noise and pressure loss.
• Cylindrical type Sound Attenuators are installed in the duct work between spaces, which must provide noise reduction of air borne noise to at least match the
• sound transmission loss of the separating structure.
• The cylindrical type Attenuators can be used where there is a demand for large amount of low frequency attenuation.
• All models of Sound Attenuators are shorter inlength, smaller in cross-section and easily installable at site. Circular duct work does not require round to rectangular transition.
• Acoustic infill media is of superior quality, non combustible and has fungi resistant characteristics complying to and ASTM C 612.
• These sound attenuators are maintanance free.


Round sound attenuators are used in ventilation and airconditioning systems to attenuate noise in fan inlet & discharge units, HVAC duct systems, radiators etc. They
are suitable for installation in either inlet or outlet pipes of axial fans, in inlet pipes of radial fans or installation in circular cross-section ducts.

BETEC CAD. sound attenuators are suitable for DW 142class C applications. Attenuator constructional integrity is suitable for pressures up to 1500 pa.



Request for Quotation

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