DOSING VALVE
(PRODUCT METERING TYPE)

Automation-ready volumetric-recipe and precise silo-discharge station

A high-precision volumetric flow-control unit for the precise scaling (flow metering) of bulk raw materials to be discharged from silos, in the storage and blending facilities of flour, semolina and feed mills. By means of its refined mechanical design and automation infrastructure, it enables product to be drawn simultaneously in the desired proportions from silos of different characters and flawlessly manages industrial grist (blending) processes.

WORKING PRINCIPLE

Raw-material reception from the discharge bottom outlet — sub-silo integration: the dosing valve is mounted straight to the outlet throat of the vibratory dischargers at the silo bases; the product shed in a controlled way from the silo reaches the valve’s precise-tolerance inlet hopper. Frequency-converter speed regulation — automated volumetric scaling: in fully automated plants the speed-control device (inverter / frequency converter) connected to the machine engages; on the recipe signal from the control room, the valve’s internal speed is set instantly, so the product volume passing per unit time is flawlessly limited. Uninterrupted proportional conveying to the collector screw — discharge to the grist line: the precisely scaled raw material is discharged straight onto the collector screw positioned below; the various products arriving from different silos this way combine on the collector screw, forming the targeted stable grist combination.

KEY ADVANTAGES

- Flexible grist capability via the speed-control device: The inner mechanism can run in variable-speed regimes through frequency converters; this technology allows the amount of product drawn from different silos to be set precisely for instant flour- or semolina-recipe updates.

- Compact bridge between discharge bottom and collector screw: The chassis is designed flat and rigid to keep the vertical distance between the sub-silo dischargers and the main collector-screw line to a minimum; it saves space and simplifies mechanical mounting.

- Volumetric flow stability: The rotor and vane geometry in the body guarantees the material flows as a uniform curtain without blocking the gravity flow and eliminating the jamming and bridging risks along the line.

- AISI 304 stainless-steel material option: Depending on the plant’s sanitation standards, the moisture of the product processed and corrosion risks, besides the standard industrial models, premium variants made entirely of AISI 304 stainless steel are available.

- Flexible production models by capacity scale: It can be configured in various industrial sizes and models to suit the plant’s hourly main processing capacity, the silo’s geometric size and the bulk-density character of the material conveyed.

ENGINEERING NOTE

The dosing valve is the most critical mechanical instrument for achieving “standard-quality product continuity” in flour and semolina mills. In milling automation (PLC/SCADA), being able to add wheat or flour with different protein, gluten or ash values to the recipe at the correct percentages (%) depends on this valve’s torque and speed stability even at low frequencies. The inner-rotor tolerances, machined by special chip-cutting methods, prevent static-pressure leaks, while the AISI 304 stainless types reliably prevent flour from sticking to metal surfaces, going rancid and forming microbiological layers on moist conditioning lines.