Belt alignment and idler maintenance are important facets of good conveyor belt health and ESS is making its replacement easier and safer for workers. Australian Mining reports.
All conveyor systems are designed to allow for some belt-drift during normal operation. However, if the belt drift exceeds its parameters, issues like spillage, conveyor structure damage, and failure to conveyor components will occur.
Over time, this initial spillage and damage creates further spillage on conveyor components, resulting in a higher degree of mistracking that causes more spillage and damage to the conveyor components down the conveyor line.
Ultimately, outcomes associated with spillage due to poor belt tracking include increased environmental contamination, interrupted production and compromised workplace health and safety (WHS) through increased dust, blocked walkways and manual handling when attending to clean up. Increased cost associated with conveyor maintenance includes fines and fees, environmental contamination and clean-up and greater frequency of component replacement.
Components like conveyor idlers that facilitate the belt’s smooth movement require replacement once they fail; the issues associated with misalignment increase the frequency of their replacement.
Idler replacement is essential as friction between the frozen idler and the conveyor belt wears away the case of the idler creating sharp edges, which in turn causes damage or excessive wear to the belt, shortening conveyor belt life considerably and increasing replacement costs.
To remove an idler, the idler frame must be removed from the belt; these are typically heavy, especially with the added weight of the conveyor belt, which increases manual handling risks. Additionally, idler replacement often involves working from heights, in confined spaces and exposed areas.
Bulk materials handling specialist ESS Engineering has traditionally offered dynamic belt training devices to solve misalignment and retractable idler frames to simplify idler changeout. ESS has now modified its belt tracker to include a quick-change idler system.
ESS utilises multi-pivot, torque-multiplying belt tracking systems that use the force of the wandering belt against the guide rollers to position a steering idler to correct the belt path continuously.
ESS belt trackers transfer the motion of mistracking to the steering idler through a parallel linkage. This requires less force to initiate the correction, and, as it steers, it needs less force to turn the belt.
The advantage of this multi-pivot design is that it allows the rollers to move perpendicular to the structure’s centreline while directing the steering idler to the proper angle, instead of pivoting and pinching the belt edge.
ESS Quick Change Idler frames allow access to idlers without the need for scaffolding, elevated work platforms, or physically lifting the belt. ESS Quick Change Idler frames are designed to lay flat when removing the idler, reducing the effort needed to slide the idler out for replacement and supporting the weight of the belt while negating the need to organise separate hardware to lift the belt and replace the idler.
Since mining conveyors are often not just long, but tall — reaching heights of up to 60 metres or more — workers may require scaffolding or elevated work platforms (EWP) to get into position, posing a considerable working-at-height risk.
According to Queensland’s Work Health and Safety Regulations 2011, working at any height over two metres in construction (three metres for housing construction) is classified as a height risk and as such fall prevention is mandatory.
ESS’s quick-change method can eliminate the need to build scaffold or call in EWPs, saving time and reducing costs.
Sales and services technician Scott Medling, who has been with the company for a year and worked in mining for over 12 years, explains how this retractable system offers several safety benefits.
“Being able to slide these idlers out onto the walkway essentially removes the working-at-height risk, and it reduces the dropped object risk,” he tells Australian Mining.
Some conveyors use a dual walkway with one ramp placed on each side, for example, while others may only have a walkway on one side. ESS’s Quick Change belt tracking system is designed to compensate for these variables.
The ESS Quick Change system allows the replacement of both idlers and tracking frame from one side of the belt. The sliding mechanism allows workers to avoid pinch points, awkward positions and heavy lifting.
“It slides the idler out from under the conveyor over the walkway where you can get into a nice, ergonomic position to make a straight lift up and down without twisting and bending,” Meddling explains.
The company is running a three-month trial at a major iron ore site in the Pilbara region of Western Australia.
The ESS engineering team worked in conjunction with maintainers at the mine site to implement the conveyor improvements as part of a continuous improvement program (CIP).
The CIP involved reducing manual handling, limiting repetitive lifting, improving ergonomics, lowering the frequency of lost time injuries (LTIs) associated with poor manual handling techniques, and minimising the risks associated with working at heights.
“ESS understands the importance of ongoing site support, whether be inspection, recommendations, problem-solving, or training of site or contractor personnel. Which is why ESS now has staff located in the Pilbara area,” Meddling concludes.
This article also appears in the February issue of Australian Mining.