Precise Packaging for 10–50 kg Powder and Granular Products

VOLDE Open-Mouth Bag Filling Machines connect beneath a silo or bin to enable powder and granular bulk solid materials to be bagged in the 10–50 kg range in a controlled, repeatable manner. Thanks to helical or belt feeding options, both free-flowing powders and fragile, granular products are packaged without damage. With a net or gross weighing principle, a pneumatic bag-holder system, and PLC-controlled dosing settings, it easily adapts to different product properties and precision needs. With carbon steel or 304/316 stainless steel body options, it offers a long-lasting, reliable solution for the food, chemical, mineral, and building materials industries.

| Net Weighing and Gross Weighing Options

The machine can be designed as net weighing or gross weighing depending on product properties and target tolerances.

In the net weighing system, the bag is weighed directly on load cells during filling. The weight is continuously measured as the product enters the bag, and once the target value is approached, the system automatically switches to slow feeding to achieve high precision. It is ideal for products requiring low tolerance, precise sales, or recipe-based accuracy.

In the gross weighing system, the product is first brought to the target weight in a separate weighing hopper, then discharged into the bag in a single pour. This method provides a shorter filling time and is preferred in applications requiring high capacity.

The feeding method is selected according to the product's structure:

• Screw feeder: Precise dosing for free-flowing powders and fine granules
• Dual screw (coarse + fine): Applications requiring high precision
• Belt feeder: Product-friendly filling for fragile or coarse-grained products

The pneumatic clamping bag holder securely holds polypropylene sacks, PE bags, and kraft paper bags in place during filling and reduces dust leakage.

| Conveying, Closing, and Palletizing After Filling

Filled bags can be automatically advanced along the line with an optional discharge conveyor. Depending on the application, the following equipment can be integrated:

• Manual or automatic sewing machines for sacks
• Heat-sealing (thermoseal) units for PE and kraft bags
• A vacuum bag-handling system that eliminates the need for the operator to lift loads
• Ergonomic transfer solutions to the palletizing station

In the PLC-controlled system, fill quantity and fast/slow feeding settings are parametrically adjusted according to product properties. Automatic transition from coarse filling to precise completion is performed.

Capacity is at the level of 2–3 bags/minute depending on the material's flow properties. For lines requiring higher capacity, the machine can be manufactured with dual filling spouts, allowing two bags to be filled at the same time.

VOLDE Open-Mouth Bag Filling Machines make the packaging process reliable, precise, and operator-friendly, delivering maximum efficiency at the final stage of your production line.