Double dosing screw conveyor with bin

Double dosing screw conveyor with bin is designed for precise handling of powdered or granular materials that require controlled dosing. With two bins and double screws in the bottom, the system ensures stable material flow and accurate extraction. It is ideal for industrial processes where additives or powders must be fed into production with consistency and reliability.

Purpose and application areas

The system is used where material must be extracted from a bin and dosed directly into a process line. Because the screw rotors are 100% filled, they act as stable dosing screws controlled by auger speed. This makes the solution suitable for additives in foundry processes, powder feeding in food production and biofuel dosing before burners in power plants.

ATEX‑compliant construction

The installation environment contains significant dust, requiring ATEX compliance. The system is therefore designed for ATEX zone 21 inside the bin and zone 22 outside the machine. BEMA includes all ATEX requirements in the CE documentation and ensures the screw auger tip speed stays below 1 m/sec to reduce ignition risk and maintain safe operation.

How the dosing system works

Each bin contains double screws that extract material evenly from the bottom. Because the screws are completely filled, they deliver predictable dosing performance. By adjusting the auger speed, operators can control mass flow accurately. This reduces the risk of bridging or inconsistent flow and allows smooth integration with existing process controls without complex mechanical components.

Engineering expertise and customisation

BEMA’s engineers collaborate with the customer’s process specialists to design the optimal screw geometry. By selecting the correct diameter‑to‑pitch ratio, the system achieves stable flow and precise dosing. This ensures each solution is tailored to material characteristics, process requirements and installation conditions, resulting in a robust and efficient dosing setup.

A reliable and economical dosing solution

The double dosing screw conveyor with bin combines precision, safety and cost‑effectiveness. Its compact design, ATEX‑compliant construction and stable dosing performance make it a strong choice for industries handling powders or additives. With low maintenance needs and easy integration into production lines, it supports long‑term operational reliability and efficient material handling.

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FAQ – Double dosing screw conveyor with bin

What is the purpose of the double dosing screw conveyor?

The system is designed to extract material from two bins using double screws that are 100% filled, allowing the screws to function as accurate dosing units. This ensures controlled and stable mass flow for additives used in a foundry process.

How does the dosing principle work?

When a screw rotor is completely filled, dosing is achieved simply by adjusting the auger speed. With known material density, the mass flow can be controlled without the need for weighing systems, making it an economical and reliable dosing method.

Is the system suitable for ATEX environments?

Yes. Due to dust in the production area, the installation is designed for ATEX zone 21 inside the bin and zone 22 outside the machine. The screw tip speed is kept below 1 m/sec to comply with ATEX safety requirements, and all documentation is included in the CE package.

Can the screw geometry be customised?

BEMA’s engineers work with the customer’s process specialists to design the correct diameter‑to‑pitch ratio, ensuring stable flow and optimal dosing performance tailored to the specific material and application.