PACE Zenith Awards 2014: Machine Builder Award sponsored by B&R
WINNER: Repeat Plastics Australia
Project: Replas' Queensland plant
When Replas was asked to consider accepting a grant to place a much needed plastic recycling facility in Queensland a few reasons were considered before accepting any money to fund this venture.
Replas is already collecting post consumer waste plastic in Queensland and shipping it to Melbourne. The company already has employees in Queensland but no office.
Queensland councils and government departments have shown keen interest in purchasing local made products and the clincher was it gives Replas a chance to culminate technologies that have been developed piecemeal over the last 23 years.
Plastic recycling is not new, many companies collect used plastic and either trade it, usually offshore or sell it to plastic reprocessors. This is usually single polymer stream plastics and mainly rigid types.
Replas specializes in mixed plastic films either diverted from landfill or intercepted before heading to Asia and moulding them into their range of products.
After trying for years to develop a control system for Replas’ fairly manual way of moulding mixed plastics into end products the company got in touch with Remtron for help with a Barber Coleman “maco” controller.
This was on one of the used injection moulding machines they had purchased ready to modify for their needs.
Barry Mathews owner of Remtron jumped at the chance to play with an emerging process within the plastics moulding industry and after a bit of discussion it was decided the maco wouldn’t be suitable for what Replas needed and using a B&R PLC would give the flexibility required for this project.
After many late nights learning what this PLC could do, Mathews was proved right – the B&R PLC has allowed Replas to continually develop better control and monitoring of its plant.
The next step was to incorporate robotics to tend the moulders. Replas uses machines that were originally designed to produce small parts – for example a few coat hangers and modify them to make parts that have an average shot size between 20 and 30 kilograms.
It was not long before they realised that a person could not handle heavy awkward shaped parts and there were OHS risks. Replas employed a young fitter with robotic experience to help in this area.
He has taken the company to the point of putting the raw material in one end of the machine and getting finished parts stacked on a pallet ready for strapping and shipping out the other with much greater process control and reporting.
Over the last five years, large servo drive motors have been developed to drive extruders rather than the standard electro hydraulic set ups or variable speed drives and gearboxes.
Replas uses machines that were originally designed to produce small parts.
There have been claims of up to 30 percent efficiency gains by using this technology so after biting the bullet Replas decided to incorporate this type of drive into the Queensland plant’s moulding machine.
The claims were accurate and the machine is very quiet while it is running. A few other mods Replas made on this project pertained to the hydraulics.
They downsized the hydraulics from a 50 kilowatt pump to a 15 kilowatt VSD geared pump. It now only turns on when needed and runs at the required speed to only move enough oil that is required for the various stages of production.
At this stage the machine is running at Replas’ R&D facility in Lilydale Melbourne and will soon to be shipped to their new site in Queensland.
Replas hopes this plant will be the stepping stone to send their technology all over the world. Plastic film recycling is one of the biggest challenges in the recycling industry and is mainly just used in waste-to-energy plants overseas.