Plastic recycling : Zero rejects and recycled materials as simple as aMC

Recently unveiled at the company's European roadshow, activeMeltControl (aMC) has been described by materials and processing experts as a game-changing feature. Automatically adapting to the injection moulding process, aMC continuously monitors for variations in holding pressure and changeover position. Once a parameter is detected as drifting towards the tolerance limits set by the user, aMC automatically adjusts the set parameters to compensate for the variation. The adjustment bandwidth is also defined by the processor.

The background to this development, which Sumitomo (SHI) Demag has been pursuing vigorously for the past four years, is the changing quality of plastics due to less virgin material and more recyclable content. "Many customers have asked for a digital solution to compensate for these variations when manufacturing precision parts with our highly efficient all-electric machines. That's why we introduced aMC as a completely independent software module to complement our established active modules," explains the company's Product Manager for Digital Solutions, Dr Thomas Schilling.

"With aMC, we can now automatically adjust to melt viscosity variations in almost all applications and materials. These variations can be due to batch variations, recyclables, regrind, drying differences, dosing variations or the use of additional additives," points out Area Sales Manager Ashlee Gough. For example, variations in the melt flow index (MFI) of 100% recycled material can now be corrected by the software. This means that process stability is now comparable to a process using virgin material.

This gives processors greater production flexibility, allowing them to use a wider range of post-consumer and post-industrial recycled material types. Even customers with defined processing references benefit, as aMC immediately addresses any variability to maintain absolute processing accuracy and stability.

“Some of the challenges of running a reprocessed material in comparison to a virgin polymer material is these need to be manually adapted and played with during processing. The introduction of technologies like aMC allows processors to monitor the melt flow of material throughout a batch which enables adjustments to be made automatically rather than being manually controlled by a setter,” notes Isy Ferguson, Managing Director at Hardie Polymers

Another advantage of the aMC is that it only sets the limits for holding pressure and changeover position. This means it can be used in all industries, including those where there are defined tolerances for validated process parameters that cannot be exceeded or overridden by machine operators. "In terms of production stability, this innovation can make a big difference to productivity and process continuity," asserts Ashlee.

Achieving more consistent part weights within a machining batch means that ROI can be exceptionally fast, claims Gough. Other benefits include improved process consistency, increased machine uptime and reduced waste. All of which contribute to increased productivity and sustainability.

Activated with a single click, aMC is a fully automated control process integrated into the Sumitomo (SHI) Demag IntElect machine's control system. It is available as an option on the company's latest IntElect 2 machine range. It can also be retrofitted to older IntElect 2 machines.