Product Description

For Maximum Noise Control…

RD 4″ Threaded Blower Exhaust Silencer

The RD blower exhaust silencers are designed for the ultimate level of pulse control and noise attenuation for the most demanding applications.  Compared to the standard heavy duty SD series, the RD silencers feature a larger shell, providing more volume capacity inside the silencer, and the interior design features one additional chamber for further attenuation.  These RD models are intended to be used as close as possible to the blower discharge connection.

Inlet Flow Rating: 480 CFM
Discharge Flow Rating: 735 cfm at 15 psig (flow based on inlet flow)
Maximum Temperature: 325 °F
Housing Diameter (ID): 14″
Overall Length: 53″
Weight: 80 lbs
This exhaust silencer is shipped LTL freight.

Paint and Coating Options
Silencers are shipped with the manufacturer’s standard blue primer coat.  For a durable, long lasting finish, pdblowers can apply special coatings with additional cost and lead time.  Our most common option includes a primer coat of Sherwin-Williams KEM KROMIK, a rust inhibiting, corrosion resistant phenolic alkyd resin primer, followed by a finish coat of Sherwin-Williams SHER-KEM® high gloss metal finishing enamel.  Contact us to discuss special coatings.

Air Tightness
Standard industrial silencers are generally not individually leak tested and occasionally very small pin-holes may appear in welds. Because of the small size of these pin-holes, their effect on typical pressure or vacuum conditions is insignificant. If 100 percent air tightness is essential for gas service or other special applications, with additional cost and lead time the manufacturer will perform a 7 PSIG leak test.

RD-4 Heavy Duty Blower Silencer, Threaded

BOM Number: 57-104-TT SKU: 22151 Category:


Maximum noise reduction
Heavy-duty all welded unit
Chamber-absorptive type

Shipping Weight: 80 lbs
Shipping Dimensions: 53 × 14 × 14 in

Universal Silencer

Connection Type:


Connection Size:

4" MPT

Silencer Type:

Chamber Absorptive

Max Flow:

480 CFM

Air Tightness

If you require an air tight silencer, the manufacturer will pressurize your unit to 7 psig to check for pin holes in the weld. This typically adds 1-2 weeks of lead time.