Oil Free Screw Blower

A screw-type blower that delivers oil-free air at very low pressures, typically 0.3 to 2.5 bar. Built to replace older lobe blowers in wastewater aeration, pneumatic conveying, and fluidization applications.

✓ 0.3–2.5 Bar✓ Oil Free✓ Replaces Lobe Blowers✓ 37–250kW

Quick Specifications

Motor Power37–250 KW

Discharge Pressure0.3–2.5 Bar (gauge)

Air Delivery10–120 m³/min

Oil FreeYes, Class 0

Noise Level72±2 ~ 80±2 dB(A)

DriveDirect Driven VSD

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Why Choose This Product

Internal Compression

Unlike lobe blowers that push air out at atmospheric pressure and let it slam into system pressure, the screw blower compresses internally. This is quieter and uses less energy.

VSD as Standard

Every unit ships with a variable speed drive. The blower matches aeration demand automatically, 24 hours a day.

Drop-In Replacement

Piping connections and mounting dimensions are designed to fit where existing lobe blowers are installed.

How It Works

Traditional roots (lobe) blowers are simple but inefficient. They compress air by trapping it between lobes and pushing it out. The screw blower uses helical rotors that compress air internally before releasing it, reducing energy use by 25–30%.

The screw blower operates oil-free, with timing gears synchronizing the rotors. Discharge pressure ranges from 0.3 to 2.5 bar gauge — the sweet spot for aeration basins, pneumatic conveying of light materials, and fluidized bed processes.

Most models include a variable speed drive as standard. Aeration demand in wastewater plants changes with incoming water volume and organic load, and the VSD adjusts output to match.

Full Specifications

Parameter	Specification
Model Range	SL-37SB to SL-250SB
Motor Power	37–250 KW
Discharge Pressure	0.3–2.5 Bar (gauge)
Volume Flow	10–120 m³/min
Oil Content	ISO 8573-1 Class 0
Drive	Direct Driven with VSD
Voltage	380V/50Hz/3Ph
Cooling	Air Cooled
Noise Level	72±2 ~ 80±2 dB(A)
Certification	CE, ISO9001

Industry Applications

Wastewater Treatment

Cement Conveying

Food Processing

Chemical Fluidization

Need Help Choosing?

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