The success of any screen in a plant circuit is the quality and the robustness of the screen media. A 30-plus-year veteran talks to Quarry about the latest advances in screen media technology.
Bill Ziogos is Metso Outotec’s screening sales support manager for the Asia-Pacific market, based in Brisbane. He has worked with operators in the quarrying industry since 1986, when he first worked for Melwire in Clayton, Victoria.
In 1991, Bill Ziogos joined Svedala, which eventually became part of Metso after the merger with Nordberg in 2001. Metso has recently amalgamated with Outotec to become Metso Outotec in 2020. With his screening background, Ziogos has progressed through each transition and his breadth of experience and knowledge has been undoubtedly valuable in every iteration.
Ziogos said the Metso Outotec screen media brand, which started life as Trellex, has proven as durable as its products.
“The Trellex brand has been renowned for a very long time. Many of the old quarry managers still refer to me as the old “Trellex man’,” he laughed. “It’s just lived forever, so now it’s about passing on this information to the up-and-comers.”
Metso Outotec’s screen media range consists of three types – modular, panel and tension systems. Modular screens, available in rubber and polyurethane, are designed for fine to medium coarse applications. Panel systems are suited to medium to primary (coarse) applications, and consist of a self-supporting screening panel with an integral steel and cord reinforcement vulcanised within each panel. Poly panels are suitable for wet screening applications and for use in sand plants. Tensioned screens are suited for fine to semi-coarse applications.
“Wire predominantly makes up the bulk of the tensioned cloths in the quarry industry, followed by rubber and polyurethane,” Ziogos explained. However, he has little doubt about the future direction of screen media.
“Modular screening is the way of the future,” he said. “When looking at it from a global viewpoint, there is certainly interest in moving away from the traditional wire-tensioned systems to a modular system.”
Ziogos added modular screens “allow for selective change-outs of individual worn panels, as opposed to a complete tensioned cloth that need changing if one section of it is worn. It also provides for fine tuning of grading envelopes through strategic placement of apertures across the deck.
“Modular screen panel retrofits can be performed to most screens currently suited to cross-tensioned cloth. The advantages of installing modular panels is not only the wear life benefits but the panels are smaller and safer for operators to handle. Manual handling is minimised, reducing the risks to operators performing screen change-outs. There is also a reduced cost in labour and less downtime,” Ziogos explained.
Tensioned screen media such as wire, rubber and polyurethane cloths can be fitted to most fixed screen plant, regardless of the manufacturer, and may suit mobile screens.
In addition to the durability of modular options, quarry operators will appreciate the added safety measures.
In 2017, the New South Wales Resources Regulator and the NSW Department of Planning, Industry and Environment released a guide on the management and maintenance of screens in the extractive industries. The guide had a heavy emphasis on the importance of proper screen management, as musculoskeletal disorders can pose a considerable risk to screen operators.
To that end, Ziogos said the “modular media has an advantage in minimising health and safety risks due to its lighter weight and manageable size. It also offers significant noise reduction. More urban quarries are looking for ways to operate with reduced dust and noise”.
Rubber screen media is an option to reduce noise emissions and frequency of change-outs. Other safety features across Metso’s entire screen range include comfortable room between decks, noise and dust reduction technology.
The durability of Metso’s range has been tested by clients in more than 50 countries, and Ziogos said his relationships across Metso’s Asia-Pacific clients have endured over the years – such is the strength of Metso’s customer satisfaction.
“It’s always a pleasure to assist our customers when they are seeking advice on how to screen more efficiently,” Ziogos said. “The way I approach it is that we are not looking to offer a product but to offer a solution to screening problems being experienced.
“Over the years I’ve had great relationships with many operators and to this day they will still contact me.”
Ziogos outlined plenty of examples of local success stories. “For many quarries around Australia, the installation of Superflex cloths has reduced pegging and blinding on site, improved grading quality and also throughput. The bottom deck of the tertiary screen is the most difficult one to access so less frequent screen cloth change-outs is more attractive to operators who gain in productivity, throughput and reduced risk on site. “Another great success story – and one of my favourites – was at a quarry in central Victoria. We converted a conventional cross-tensioned screen into a modular panel system. The benefits of this conversion lead to other screens being converted in both the crushed rock plant and tertiary plant.”
SCREEN MEDIA OPTIONS
While the Trellex Superflex is perfect for tackling pegging or blinding issues at the tertiary screening stage, Metso Outotec has a product to match every stage of production.
“The primary screening side can be effectively handled by Trellex panel systems such as the 610MP/Panelcord in separations from 50mm and higher,” Ziogos said.
“For separations less than 50mm the Trellex LS modular system is a good option. For finer separations below 10-15mm, a thin flexible membrane can avoid the pegging, due to flakiness of the material.
“Whatever the screening application, there is a screening media solution to match,” Ziogos summarised. “Screen media is adaptable to all environments and tasks. The range is designed to offer maximum productivity without compromising quality.
“When fitting a modular system, our Trellex Trellstep system is the easiest to install, as there is no need to convert existing screen decks. It’s a quick, easy retrofit by installing our ‘Snap-On’ rail to an existing deck.”
If durability, cost-efficiency, and added safety aren’t enough, Ziogos added Metso Outotec is a proud contributor to meeting science-based targets of a maximum of 1.5°C global warming.
With a brand promise of being “the partner for positive change”, Ziogos said quarrying producers can be assured of Metso’s clean-cut, trustworthy world of stress-free operation.
For more information on Metso’s screen media, visit mogroup.com/products-and-services/parts/screening-media/ •