Soniplas ultrasonic technology from Matrix Moulding Systems reduces energy use for injection moulder Barkley Plastics

Andy Watts, Commercial Manager, Matrix Moulding Systems Ltd., introduces the Soniplas system, an ultrasonic technology designed to reduce energy use for injection moulders.

A new technology with the potential to transform injection moulding has completed its pilot phase and is now on the market with promising results, including cutting energy use by up to a third.

The Soniplas technology, created by Matrix Moulding Systems (a spin-out of The Technology Research Centre), was first demonstrated by Barkley Plastics over six months in 2021. During this time, it was found to cut energy use by 34 per cent and cycle time by up to 27 per cent, transforming both the profitability and productivity of injection moulding.

These reductions are important from a sustainability and carbon savings perspective, but increasingly important for regulatory and commercial social responsibility. With spiralling energy costs at the forefront of moulders’ minds, energy reductions are another hugely important benefit.

The Soniplas system, a retro-fit system using ultrasonic energy to enhance molten polymer flow, was recognised with a BPF special commendation (Horners) award and Plastics Industry Award for Best Technology Application in 2021.

The energy and carbon savings are made possible through reduced polymer melt temperatures, which results in lower heating and cooling energy requirements, plus cycle time savings from faster cooling. It enables embodied carbon to be reduced in moulded parts, while also becoming more productive with existing moulding machines.

It applies ultrasonic energy to excite the molten polymer, providing a temporary reduction in viscosity, which enhances the flow as it is injected. The low-power ultrasonic energy is only used to vibrate the molten polymer, with all material heating coming from the barrel heaters.

The polymer melt is vibrated using transducers mounted within the melt stream, between the nozzle and the tool cavity.

The low energy vibration of the polymer melt enables Soniplas to unlock the thixotropic (shear thinning) properties of polymer materials, and with ultrasonic energy being transferred into the melt with transducer amplitudes of just a few microns, the acoustic modelling of each transducer is a critical part of each system build.

Each sonotrode and booster system is acoustically modelled to ensure resonance at the correct operating conditions, enabling the system to ‘ring’, just like a tuning fork.

Systems are configured to give optimum performance for a range of different settings.

Crucially, physical testing of parts moulded with and without Soniplas flow enhancement validates no change in moulded part physical properties. Similarly, before and after MFI testing also validates no changes to the moulded material properties.

For existing, difficult to mould parts with a high scrap rate, the system may be used to improve part quality and reduce scrap.

The flow enhancement reduces the injection pressure required, making the part easier to mould around complex tooling features. In addition, with injection pressure defining the clamp force requirement for a given mould, Soniplas can be used to reduce the clamp force requirement for a given tool.

For those designing new parts and tooling, the technology provides an additional design freedom, enabling a downgauging of wall thickness, helping to satisfy those driven by the lightweighting or material saving agenda.

Soniplas systems can be supplied in a range of formats to suit the application. Traditional cold runner tools are serviced through a fixed platen mounted system – a range of bolster sizes are available and can be specified by the customer. This format can also be used to run heated sprue bush tooling.

Users may be able to integrate Soniplas into their hot runner systems, although this is likely to be more attractive for new build “Soniplas ready” tooling – something which Barkley Plastics is keen to offer other moulders from their in-house toolmaking facility.

The first pilot of Soniplas at industrial scale was supported by the Industrial Energy Efficiency Accelerator (IEEA), funded by the UK Government’s Department for Business, Energy and Industrial Strategy.

This provided funding and support for the technology to be installed at Barkley Plastics’ Birmingham site then to report on findings.

This scheme is preparing to announce its successful Phase three applicants and accepting applications for Phase Four now.