Conveyor equipment manufacturer Melco has expanded its product offering after launching a new range of retractable V-return idlers onto the South African mining market.
The Melco retractable V-return idler design includes a permanently installed main frame, with end plates having access cutouts for the retractable sliding frames carrying the return rollers, which may be sloped at the standard 10º or as required.
The rollers are protected from dislodging by two full-span angle sections either side of the rollers and each roller projects 20 mm above these angle sections. When retracted, the belt lands on these angle sections within 100 mm, leaving the roller free for easy retraction and reinstallation. This ensures improved safety as the belt does not have to be lifted.
“This innovative design allows a single worker to pull out a roller frame, which can be more than 1 m long, while standing on a standard 750 mm walkway. “To undertake this process, the workers simply need to unbolt the sliding frame from the side of the main frame and pull it out.
“After replacing the roller, the frame is returned to its operating position,” Melco sales and marketing director Craig Warmback explains.
Meanwhile, Melco MD Gavin Hall highlights that the company’s range of retractable V-return idlers has been adopted by diversified miner Exxaro’s Grootegeluk coal mine, which is developing a coalfield to supply the Medupi coal-fired power station, in Limpopo.
“The stringent safety requirements at the mine’s 30-m-high gantries necessitated a solution to improve safety when replacing damaged or worn rollers,” he says.
Owing to these safety requirements, Melco was approached to design a retractable idler that would make it easier and safer for workers to perform maintenance in this challenging working environment.
“Previously, to replace a roller, a team of workers wearing safety harnesses had to climb inside the gantry, lift the return belt clear of the roller, and uncouple and remove the heavy roller and manhandle it to the walkway. “There sometimes are other complications to take into account, like underpans that prevent material on the loaded belt from falling to the ground.”
Hall says the process of changing rollers in a mining environment can be complex and challenging.
In addition to improving its safety standards, Warmback points out that the Grootegeluk coal mine will also save on overhead costs in the long term, owing to the Melco retractable V-return idlers’ ability to reduce scheduled downtime and maintenance risks.
“The elimination of belt lifting during the change-out task saves a significant amount of time and, consequently, money, owing to the fact that only one worker is required for the entire process. “Further, the only tool required is a spanner; therefore, the risk of belt damage and roller falls is substantially reduced.”
Meanwhile, going forward, Hall says he is confident that the Melco range of retractable V-return idlers will gain popu- larity, especially as mining operations seek innovative methods to improve their safety standards.
“Melco is able to install the retractable idler system to any existing conveyor belt that has dual access on both sides of the conveyor walkways. “Retrofitting an existing structure that is being modernised or upgraded to handle larger tonnages is cost effective.
“Melco has the capacity to manufac- ture retractable V-return idlers for belt widths up to 2 100 mm that are operating on gantries with walkways as narrow as 750 mm,” he states.