The VacuUM

About

The VacuUM project is led by the University of Malta in close cooperation with Toly Products Ltd as the industrial partner. The project is funded for 3 years by the Malta Council for Science & Technology through the FUSION: R&I Technology Development Programme (R&I-2020-004T).

Problem Background

Plastic injection moulding is widely used in the manufacturing industry, both worldwide and locally. It is identified as one of the main energy-consuming industrial processes in Malta. In injection moulding, plastic parts are produced by pressurizing molten plastic to fill a cavity. Air trapped in the mould cavities is one of the problems that often occur during the process. This causes further problems such as incomplete cavity filling, which injection moulding machine operators commonly try to solve solely by increasing the injection pressure. Even though the dimensions are accurately achieved, this is not a smart solution since it causes low-quality products due to the high residual stress or even material degradation. This approach also results not only in a significant reduction in the lifetime of the mould and machine but also in a significant increase in energy consumption, which makes the injection moulding process less sustainable.

Our Goal

To solve such a problem, an active vacuum venting system is required to evacuate the trapped air out of the cavities prior to the melt injection stage. However, all active vacuum venting systems available on the market are quite complex. Dependent on the part size and geometry as well as the number of mould cavities and their layout, every single cavity including its movable components such as ejector pins and sliders must be sealed. This requires complex machining to place the seals or shut-off pins and costs additionally a couple of thousand Euros. In many cases, it is even impossible to place seals due to a lack of space. Besides, such systems are relatively expensive.

The main goal of the VacuUM project is to develop a small and affordable mould vacuum system to solve issues associated with air trapped in the mould cavities. To successfully achieve this goal, the Department of Industrial and Manufacturing Engineering (DIME) of the University of Malta has teamed up with Toly Products Ltd due to their relatively high number of injection molding machines and continuous efforts to improve the sustainability of their manufacturing processes.