The subject of today’s case study is a leading company in the plastic injection molding sector, specializing in the production of molded components for the designer furniture and electronics industries.

Operating 24/7 and meeting the high-quality standards demanded by international markets, the efficiency of the processing department is critical to the company’s business.

 

The challenge: overcoming the inefficiency of isolated pellet transport systems

The company asked Vismec to carry out a plant overhaul to address problems and inefficiencies resulting from fragmented management of the press feed system. The main issues identified were as follows.

• Risk of contamination: increased risk of human error due to the manual transport of plastic pellets bags and the use of individual feeders mounted on the machines.
• Energy inefficiency: constant operation of many inefficient single-phase motors, with a significant impact on energy consumption.
• Frequent machine downtime: difficulty monitoring material levels due to the lack of a centralized control system, often resulting in sudden production interruptions. 
• Suboptimal space organization: due to material loading directly at the press, occupation of a significant portion of the production area by storage containers, pallets with big-bags or octabins, and dehumidifiers, hindering operator movement and creating a cluttered and poorly organized workspace. 
• High component wear: premature wear of hoses and receivers in contact with materials, caused by the use of glass-fiber-filled materials. 
• Workplace safety: risk to operators caused by the frequent passage of forklifts used to handle big bags.

The solution: a smart pneumatic conveying system

The goal of the plant overhaul was to create a fully automated centralized feeding system capable of transporting pellets from the storage area, equipped with containers, big-bag unloading stations, and dryers for pre-dehumidification of the resin, to over 20 consumption points distributed throughout the department: injection molding machines, on-machine resin dryers, and screw mixers.

The work carried out by Vismec for the overhaul and reorganization of the plant had multiple effects, as described below.

Storage and feeding

Two big-bag emptying frames were installed for raw material handling, allowing complete emptying without requiring operator intervention to reposition a suction nozzle. The frames are equipped with a minimum level sensor with an alarm, which provides advance warning when the material is running low, and the big bag needs to be replaced.

The system also includes new containers with bag-breaking grids for handling materials in 25-kg bags.

Conveying and distribution

To direct each type of granule (from storage or dryer) to the correct machine, a manual sorting unit has been installed, featuring a switching system and duct cleaning devices, which eliminates the risk of cross-contamination and material mix-ups.

The individual feeders have been replaced with two VB62 two-stage side-channel blowers, controlled by inverters: the blowers ensure optimal vacuum even over long distances (over 70 meters in this project for the presses located farther away). The inverter modulates power based on actual demand, reducing consumption, and the dual blower with automatic switching valves ensures continuous operation even if one of the two units fails. 

The distribution system, made entirely of stainless steel with VISCARB-reinforced bends, connects each press to the storage area via dedicated piping.

Filtration and quality of material

To remove dust from all molding processes, the high-efficiency Vismec DR4 dual cyclonic filter was adopted. It improves plant cleanliness by removing dust and reducing waste in all molding processes without interrupting material feed to the presses.

The line cleaning valves eliminate material buildup in the pipes at every production changeover, ensuring the effective transfer of granules from the source to the press.

New stainless steel hoppers with internal flaps reinforced with VISCARB and new volumetric master feeders connect all the presses to the system, adding the option of coloring the material directly in the press on machines that previously lacked this capability.

Control and monitoring 

The FW50 centralized control system manages all hoppers connected via a serial line, ensuring proper organization of loading queues and clear and fast communication of system operating status to operators, thanks to the additional touch panel.

The connection between the FW50 control system and the VISBUS supervisor allows for the acquisition of all operating data, enables remote management via a web server, and, through the OPC-UA protocol, interfaces with the customer’s MES (Manufacturing Execution System) software for optimal plant management in line with Industry 4.0.

The results: productivity and sustainability 

The new plant has already delivered significant benefits in its first six months:

• energy efficiency, with lower conveying costs;
• product quality, with reduced waste, thanks to the absence of contamination and dust;
• production space, with more room available around the presses for new lines and packaging systems;
• maintenance, meaning fewer interventions for filter cleaning and replacement of worn components;
• labor efficiency, with reduced manual reloading operations of individual presses;
• safety, with the elimination of forklift traffic in the production aisles.

This case study demonstrates how targeted initiatives implemented according to Industry 4.0 principles can bring significant benefits to the furniture components sector. Automating the transport of plastic pellets, in fact, means investing both in finished-product quality and in process sustainability.

Want to find out how to optimize your plastic processing department? Contact us to schedule a technical site visit and an analysis of your energy consumption.