In the plastics industry, pneumatic conveying of granules and pellets is a very important auxiliary technology. A well-designed and efficient conveying system ensures efficient and fast processes, and its components can be adapted to meet the specific needs of the user company.

In this article, we will present in detail how pneumatic granule conveying systems work and the advantages offered by the solutions designed and implemented by Vismec in this sector.

Pneumatic conveying of plastic granules: how it works

Pneumatic conveying is a method of handling solid materials, such as granules and pellets, using an air or gas flow. The kinetic energy of the flow pushes the materials through a system of pipes and ducts, allowing for a fast and secure transfer.
Unlike traditional conveying methods, such as belts or screw conveyors, pneumatic conveying reduces the risk of contamination and damage to materials. This makes it perfect for the plastics industry, where maintaining the properties of plastic granules and preventing contamination is crucial to ensure the high quality of the finished product.

The operation of a pneumatic conveying system relies on several key components, including the compressor, transport pipes, valves and vacuum units.

  1. The process begins with the suction of granules through a Venturi vacuum unit, which creates a vacuum in the system, allowing the materials to be extracted from their container.
  2. Once aspirated, the granules are transported through pipes of various lengths and diameters, according to the specific requirements of the system in terms of speed, flow rate and distance.
  3. Along the way, compressed air helps keep the materials in suspension, preventing material build-up, pipe clogging and, as mentioned, granule contamination.

The applications areas of pneumatic conveying in different industries are more than one. For example, in the food, chemical and pharmaceutical industries, pneumatic conveying helps manage powders, granules and ingredients in a hygienic and safe manner, both for process operators and end consumers. In the mining and metallurgical industries, pneumatic conveying is used to move minerals, metal powders, heavy and abrasive materials. In the wood industry and building materials manufacturing, it is used for handling chips and powders from various materials.

In the plastics industry, similarly, pneumatic conveying is used for the conveying of granules and pellets, but also for the handling of powders and bulk materials, helping to simplify and speed up production processes. In particular, conveying systems support moulding, extrusion and blow moulding processes, where speed and efficiency in the conveying stage ensure a better manufacturing organisation, material quality and successful processing.

Moreover, pneumatic granule conveying systems can be integrated with other machinery, such as storage systems and mixers. Thanks to its capability to adapt to various applications and plant configurations, pneumatic conveying represents a versatile, efficient choice tailored to the specific needs of each company.

Vismec plastic granule conveying systems

In the plastic processing operations, Vismec pneumatic conveying systems are naturally involved in machine feed phase to ensure the continuous and optimal flow of materials. The granules are transferred from storage containers directly to processing plants, such as injection moulding presses or extruders. In these steps, the speed and efficiency of pneumatic conveying significantly help maintain productivity and reduce downtime.

Vismec offers centralised pneumatic conveying solutions for plastic granules that provide numerous advantages to the companies. Our plants, ranging from small to more complex systems, enable a rapid and controlled conveying of granules, optimising production logistics.
In particular, the larger centralised systems can manage up to 48 conveying stations, thanks to technically advanced control systems. Such plants can be equipped with various accessories which help maintain a clean working environment, optimise consumption, and facilitate maintenance. We have discussed this in more detail in the dedicated article.

A key element in the effective operation of granule conveying systems is the Venturi vacuum cleaner. This device, which operates by using the principle of vacuum, ensures an efficient aspiration in the initial phase of the process. By generating a vacuum within the system, Venturi hopper and loader allows for a quick extraction of materials without damaging them.


Venturi vacuum cleaner recently designed and manufactured by Vismec stands out for its reliability and ease of operation. In fact:

  • it has a simple, compact design and can be easily integrated into various conveyor systems;
  • thanks to the absence of moving parts, it requires little maintenance compared to other aspiration systems;
  • it can be installed on a drying hopper;
  • it efficiently vacuums materials without damaging them, and, thanks to its unique cyclonic vortex, it ensures an even more effective dust separation.

Venturi units tend to consume less energy than other aspiration devices. The vacuum cleaner produced by Vismec, in addition, allows the power of the conveying air to be adapted via a flow regulator, further optimising consumption.

As we have seen, the pneumatic conveying systems for plastic granules designed and manufactured by Vismec, in all their components, are not only high-performing but also adaptable to the specific needs of companies and capable of managing even complex conveying setups efficiently. Would you like to know more about it? Contact our team.