A Rotary Unloader,also known as a rotary valve,star-shaped unloader,rotary airlock or rotary feeder,is a core industrial device for quantitative,continuous,and airtight discharge/feeding of bulk solid materials.It is widely applied in pneumatic conveying,dust removal,and material storage systems across multiple industries.

1.Structure

It consists of four key components:

Housing:With inlet/outlet flanges(square/round available),providing a sealed passage for materials.

Rotor(Star-shaped Impeller):Equipped with multiple blades(usually 6–12),forming material chambers between blades.

Drive Unit:An electric motor paired with a reducer to control rotor speed(fixed/variable speed optional).

Sealing&Bearings:High-performance seals and heavy-duty bearings to prevent air leakage and ensure smooth operation.

2.Working Principle

Material from the upper hopper/bin falls into the chambers between the rotor blades by gravity.

The motor drives the rotor to rotate at a constant speed;materials are carried downward by the blades.

Materials are discharged from the bottom outlet as the rotor turns,achieving volumetric metering and continuous discharge.

The close clearance between rotor and housing creates an airlock effect,isolating pressure differences between the upper(positive/negative pressure)and lower sections to prevent gas leakage.

3.Core Features

Airtight&Pressure-Resistant:Blocks air flow while discharging,suitable for both positive-pressure and negative-pressure pneumatic conveying systems.

Precise Metering:Fixed volume per rotor rotation;adjustable discharge rate via variable speed drive.

Wide Material Compatibility:Handles dry powders,granules,pellets,and small lump materials(e.g.,flour,cement,grain,fly ash,plastic particles).

Durable&Low Maintenance:Robust construction(cast iron,carbon steel,stainless steel 304/316 available);wear-resistant options for abrasive materials;long-life bearings reduce upkeep.

Temperature Adaptability:Standard models handle up to 280°C;high-temperature versions for 450°C+available.

4.Main Applications

Pneumatic Conveying Systems:Uniformly feed materials into pipelines while maintaining system pressure stability.

Dust Collection&Environmental Protection:Discharge dust/ash from dust collectors(baghouses,cyclones)without breaking vacuum/pressure.

Material Storage&Batching:Serve as bin discharge valves for silos/hoppers;meter materials for mixing/packaging.

Industries:Environmental protection,metallurgy,chemical,food&beverage,grain processing,cement,pharmaceuticals,plastics,and mining.

5.Technical Parameters(Typical)

Capacity:0.8–120 m³/h.

Rotor Speed:10–60 rpm(variable speed optional).

Motor Power:0.55–7.5 kW.

Pressure Rating:Up to 0.6 MPa.

Inlet/Outlet Size:DN100–DN600(4"–24").

Summary

The rotary unloader is an indispensable device for bulk material handling,integrating discharge,metering,and airlock functions.Its reliable performance,flexible design,and wide adaptability make it a preferred solution for industrial material processing.