Net vs gross system in bag filling machines: impact on accuracy and speed

Your production line is running at full speed, but the output falls short. Every second of delay during filling simply costs your company money. In addition, small weight deviations cause unnecessary product loss or dissatisfied customers. The choice of the right weighing system is therefore crucial for your profitability.

What exactly is a gross system?

With a gross system, the machine weighs the product directly in the bag. The empty bag hangs on the filling spout and acts as a weighing container. Once the desired weight is reached, the product supply stops. This process is relatively simple and the machine is compactly built.

How a net system works

A net system works with a separate weighing hopper above the filling spout. The machine pre-weighs the exact dosage in this hopper. The system then pours the complete batch into your bag in one go. This completely separates the weighing process from the filling process.

Impact on packaging speed

Speed is often the decisive factor in a modern production facility. A net system is considerably faster than a gross system. While one bag is being filled and discharged, the hopper is already weighing the next batch. This overlapping process enormously increases your packaging speed.

Accuracy and product loss

Besides speed, you naturally also want maximum precision during filling. A gross system can be influenced by the movement of the bag. A net system can weigh more stably and therefore delivers higher weighing accuracy. At Votech, we integrate advanced weighing techniques to minimise product loss.

Which system suits your product?

The properties of your bulk material ultimately determine the ideal choice. Not every material flows equally smoothly through the production line.

• Choose a gross system for strongly dusting or sticky products.
• Use a net system for free-flowing granulates and pellets.
• Always consider the desired capacity of your total solution.

Frequently asked questions about net vs gross systems in bag filling machines

Can I upgrade a gross system to a net system later?

This is possible if the production facility has the right space available.

Which system is most suitable for powders?

For fine powders, we often recommend a gross system. Powders can stick in a weighing hopper. By weighing directly in the bag, you prevent contamination and residual material in the machine.

How does the weighing system affect my end-of-line automation?

A constant desired output is essential for an efficient packaging line. A faster net system ensures a continuous flow to your palletizing machines. If desired, you thereby maximise the capacity of your entire integrated portfolio.

Conclusion

The choice between a net and gross system determines the efficiency of your packaging process. Speed, precision and product properties play an absolute key role here. Do you want to structurally increase the productivity of your facility? Contact the experts at Votech for advice on our Duravant Lifecycle Services and innovative total solutions.