Sunday 11th Apr, 2021

Stealing uses for steel

DYNA Engineering’s HDPE (plastic) conveyor guards are providing Australian miners with a sustainable solution for site safety.
Thomas Greaves

DYNA Engineering’s HDPE (plastic) conveyor guards are providing Australian miners with a sustainable solution for site safety.

In 2017-18, around 3.4 million tonnes of plastics were used, with only 9.4 per cent recycled, according to the World Wildlife Foundation

Of that 320,000 tonnes, around 46 per cent was reprocessed in Australia with more than half exported for reprocessing.

One of the reasons that a significant amount of plastic waste is sent overseas is because Australia does not currently have a large, sustainable market for recycled waste products.

Thomas Greaves, General Manager of DYNA Engineering, says sustainability and recycling within the mining and manufacturing industry is the direction these industries are moving, which is why the company has developed its own high-density polyethylene (HDPE) manufacturing line that takes advantage of recycled materials.

“Our customers care about sustainability and using new plastic hurts the environment,” Greaves says.

Related stories:

“We’ve also seen the popularity of HDPE start to dramatically increase since we released our new conveyor guards.”

HDPE is a thermoplastic polymer produced from monomer ethylene. With a high strength-to-density ratio, it is commonly used in the production of plastic bottles, corrosion-resistant piping, geomembranes, plastic flooring and componentry.

When it comes to the mining and bulk handling industry, it has a number of significant benefits when compared with steel guards. One of the main differences is weight. Steel guards are often heavier than 15 kilograms, which can present heavy lifting risks.

HDPE can be up to 40 per cent lighter and DYNA’s guards can be removed in a matter of minutes. Steel guards require costly on-site welding, grinding, cutting and a hot works permit to make simple modifications. To modify a HDPE conveyor guard, it’s easy to just shave a few millimetres off where needed.

Installation is easy, with the guard simply sliding into place and fastened with two bolts so it can’t be removed. No complicated instructions or special skills are required, reducing the likelihood and risk of accidents.

“Steel guards can also rust and corrode where HDPE does not,” Greaves says. “Additional advantages are they will never need repainting as the colour is inherent in the material used and they are metal detector friendly.”

Due to the size of the mesh, painting steel guards is a costly and wasteful process. A lot of paint is used, and a significant amount is lost in the process. Often, operators resort to hand painting, which is very time consuming and expensive.

DYNA Engineering recently manufactured around 660 square metres of HDPE conveyor guards for three conveyors, using about 12 tonnes of recycled plastics. They were produced for an iron ore operation in WA’s Pilbara, which requested them to be made in the colour pink, to support breast cancer awareness.

The decision to use pink came up in early talks and was easy to implement as part of the manufacturing process, because the recycled plastic is supplied by colour.

“The site also required the guards to allow employees to work alongside it while running. The weight of steel guards would have made this impossible as the structure could only carry so much,” he says.

The guards have a life span of about 10 to 15 years and are themselves fully recyclable, meaning they can be melted down and recycled over and over.

Greaves says the mining industry is the perfect sector for recycled material uptake, as the projects require vast amounts of construction materials.

“Using recycled plastic for smaller projects is helpful, but there’s an opportunity to really build an end market for recycled products. In addition, the Federal Government has announced a $500 million package to help build an end market for the recycled material,” he says.