Fluidizing Pressure Packages

Posted on November 22, 2025

When bulk materials are stored in silos, positive displacement blowers are often used to inject air into the bottom of the silo where it will pass up through the material. As the air molecules move up through the empty spaces between the granular material in the silo, it expands the volume of the material and causes it to act more like a fluid that can be metered out of the silo much more easily. This process is called fluidization.

These six packages feature a Roots 45 URAI blower, directly coupled to a 10 HP TEFC motor.

Equipment Selection

Roots 45 URAI Positive Displacement Rotary Blower
Direct Drive Base, Custom w/ Guard
Motor, 10 HP, TEFC, Premium Efficiency, 1800 RPM, 1.15 SF, 230/460 Volts, 3 Phase 60 Hz
Drive, Direct-Coupled
Inlet Filter/Silencer, 2.5 ”, Paper element, CCS-2.5
Discharge Silencer, 2″, Chamber Type, Universal URB-2
Discharge Flex Connector, 2.5″, Silicone Impregnated Fiberglass
Relief Valve, Pressure, Weighted Type, 2″, Set at 9 PSI
Check Valve, 2″ MNPT, EPDM Seal
Pressure Gauge, 2.5″ Dia., 0-15 PSI, Liquid Filled, Snubber & Gauge Cock

Direct Drive Fluidizing Blower Packages, featuring Roots 45 URAI blowers

Conditions
– Inlet Volume: 138 ACFM (121 SCFM)
– Site Elevation: 175′
– Barometric Pressure: 14.6 PSIA
– Inlet Temperature: 100 °F
– Inlet Pressure Drop: 0.3 PSI
– Blower Inlet Pressure: 14.3 PSIA
– Discharge Pressure Drop: 0.2 PSI
– Discharge Pressure: 8.0 PSIG
– Blower Differential Pressure: 8.5 PSI

Performance
– Design Speed 1780 RPM (49% of maximum)
– Shaft Power: 8.3 BHP
– Discharge Temperature: 238 °F
– Differential Temperature: 138 °F (61 % of maximum)
– Discharge Volume: 108 ACFM
– Power at Relief Valve: 9.3 BHP
– Estimated Noise Level: 86 dBa at 3 feet