Rotary Feeder Rotor Designs Compared: Which One Fits Your Material?

Once bore size and pressure rating are settled, the detail that actually determines how well a rotary feeder performs on your material is rotor design. ENZAC offers eight configurations, and picking the wrong one is a common source of leakage, jamming, or poor metering accuracy that gets blamed on the valve when it's really a rotor-material mismatch.

Open Fixed Vane (Standard)

The default configuration for general-purpose metering and discharge duty on free-flowing powders and granules. Suits the majority of applications where material isn't especially fibrous, sticky, or dimensionally awkward.

Open Fixed Chamfered

A variant on the standard vane with chamfered edges, reducing the risk of material shearing or jamming at the housing tolerance — useful where material particle size or friability makes standard square-edge vanes prone to nipping product between rotor and housing.

Reduced Capacity / Reduced Capacity Multi-Vane

Smaller pocket volume per revolution, giving finer metering control at lower throughput — relevant where precise low-rate feeding matters more than maximum capacity.

Replaceable Blade

Vanes that can be swapped without replacing the full rotor — worth specifying for abrasive materials where vane wear, not the rotor body, is the recurring maintenance item.

Closed Rotor

Fully enclosed pockets rather than open vanes, giving a tighter seal for applications where minimising air leakage across the valve is the priority — typically higher-pressure duty.

Staggered Pockets (Twin Outlet)

Offset pocket arrangement feeding two outlets, suited to applications needing split or dual-stream discharge from a single valve.

Helical

A helical vane arrangement that smooths pulsation in discharge, relevant where downstream equipment is sensitive to the pulsed, pocket-by-pocket discharge pattern of a standard rotor.

Getting the Choice Right

The right rotor isn't about picking the most feature-rich option — it's about matching pocket design to your material's particle size, abrasiveness, and friability, and matching seal design to your actual pressure differential requirement. A standard open vane rotor running an abrasive material will wear faster than a replaceable-blade design would have; a closed rotor spec'd where it isn't needed adds cost without adding value.