Losing Pressure or Product Control at Your Pneumatic Conveying Inlet?

Feeding bulk powder or granules from a hopper into a pneumatic conveying line, or discharging from under a cyclone or filter receiver, isn't a place you can just open a gate and let material fall through. Without a proper metering and sealing device at that transition point, you lose the pressure differential the conveying system depends on — and you lose control over how much material enters at once.

Where an Open Discharge Point Breaks Down

Pressure differential leaks away. A pneumatic conveying system, positive or negative pressure, relies on a sealed transition point to maintain the pressure difference that actually moves material through the line. An open or poorly sealed discharge point bleeds that pressure away, and conveying performance drops with it.

Uncontrolled discharge floods the line. Without metered feeding, material can dump into the conveying line faster than it can be carried, causing blockages or surges rather than a steady, conveyable flow.

Dust and product loss at the transition point. An unsealed discharge from a hopper, cyclone, or filter receiver is a point where fine material and pressurised air both escape — a housekeeping and product-loss issue on top of the conveying performance problem.

High-temperature or high-pressure applications need more than a simple gate. Processes running elevated temperature or pressure need a device rated for those conditions at the discharge point — not a fabricated gate that wasn't engineered for the duty.

Where a Rotary Feeder Fits

A rotary feeder — also known as a rotary airlock, rotary valve, star valve, or cell wheel feeder — meters bulk powder or granules from hoppers into pneumatic conveying systems while maintaining the pressure differential the system depends on. A rotor with fixed vanes turns inside a close-tolerance housing, so material drops into each pocket at the inlet and discharges at the outlet, with the rotor itself forming the seal between the two sides.

ENZAC supplies rotary feeders across bore diameters of 150–600 mm, rated to 3.5 bar maximum pressure (CVH model) or up to 21 PSI for blow-through types, and up to 300°C maximum temperature — covering discharging and metering duty, blow-through models, sanitary quick-clean variants, and granule discharge configurations. Rotor vane counts (6, 8, 10, or 12) and drive speed (3–33 RPM with VFD capability) are matched to your material and required throughput.

Where the Detail Actually Matters

Rotor design isn't one-size-fits-all: open fixed vane is the standard configuration, but reduced capacity, replaceable blade, closed rotor, staggered pocket (twin outlet), and helical designs each suit different materials and duty conditions. Construction ranges from mild steel through 304/316 stainless for sanitary applications up to Hastelloy for corrosive duty, with interior coatings (tungsten, Teflon, ceramic, hard chrome) available for abrasive materials.