Technology is making conveyor idler change-outs safer and more effective for maintenance staff. Safe to Work explains.
It is important to make sure idlers are kept in good working order to maximise the effectiveness of conveyor setups. Idler rollers go through a lot of wear and tear at mine sites as they support the locomotion of conveyor belts that often bear the weight of heavy loads.
Once spent, these conveyor rollers require changing, a manual handling process that can put site workers at risk in a variety of ways. Rollers can also catch hands, hair and clothing at various nip points, particularly in the spaces between the belt and carrier rollers, near drive pulleys, sprockets and other components.
Change-outs also present working at height risks for elevated conveyors, as well as the risk of back injury and strains associated with lifting the rollers (which can easily weight between 20–50 kilograms each, depending on the roller type in question). The lifting of heavy conveyor belts to gain access to the rollers underneath can also prove a cause for concern in this regard.
“It is not unheard of for rollers to be lost off the edge of a walkway gantry and fall to the ground below, causing a serious drop hazard,” says Ryan Norris, co-founder and chief executive officer of Mackay-based tech company Vayeron.
“If we can cut-down on the quantity of rollers being changed in the industry, the frequency of these events will be reduced.”
Vayeron is responsible for the Smart-Idler, a technology embedded inside conveyor rollers that provides real-time monitoring that can alert staff to roller failures. The company went through five years of research and development before launching last year.
Aside from the potential safety issues, which are of utmost importance, idler roller changeouts can also bring pain to the mine sites themselves due to the reduced productivity associated with production stoppages as people work to replace the components.
According to Norris, mines are wasting time, money and introducing the risk of staff injuries through excessive roller maintenance.
“The industry generally changes more conveyor idlers out than is necessary,” Norris says.
“Large batch change outs as a pre-emptive maintenance strategy is common and is not only wasteful but also comes with additional expense. Additionally, batch change outs mean that personnel are engaging in a higher number of manual handling tasks than is really necessary.”
There are several companies working in the Australian mining space who are attempting to improve this situation for workers through automation. One of the more prominent examples is Sandpit Innovation, which has developed an autonomous robot called the Spidler, which can change conveyor rollers on the fly, eliminating the need for workers to become involved.
The machine sits above the conveyor on a specially built gantry system and lifts the belt while it is still running before using a robot arm to remove the old roller to replace it. The majority of the belt length can be serviced by the Spidler, which also influences the upstream part of the process.
Company director Aaron Carter says that the Spidler was developed as part of Sandpit’s vision for the “conveyor of the future” in response to a mining client that had endured several staff injuries as a result of batch roller changeouts.
While other robotic roller changers, they are usually truck-mounted, which means they lack the improved access of Spidler’s gantry-mounted system.
“Obviously everyone likes to think of the production benefits of not having to stop a belt but from a safety benefit perspective it’s also significant,” Carter tells Safe to Work. “On any given mine site they’re changing thousands of rollers by hand, so the whole concept behind the Spidler was to remove the lifting of the belt and the manhandling of replacing a roller along 90–95 per cent of the length of the belt.”
The Spidler can also offer indirect safety benefits through its condition monitoring technology, which can check the rollers’ operating temperature with thermographic imaging.
Conveyor belts can catch fire as can combustible material transported via a conveyor. Common causes of conveyor fires include friction due to misalignment or a loss of belt traction, as well as belts that have combustible residue on their surface. However, conveyor roller failure is a leading cause. The motion of conveyors can also cause fire to spread quickly, which is an additional incentive for effective monitoring.
“We can get really good, reproducible scans of temperature over time,” Carter says. “For example, we can see the same temperature in the same operating environment on the same roller multiple times a day or once every day, so that understanding of the temperature zones is really good for detecting a threshold breach or abnormality in temperature.”
Norris says Vayeron’s heat monitoring is particularly beneficial for underground coal mining operations, where manual monitoring of rollers is not always practical.
“In Australia, there is a statutory requirement to monitor and limit all surface temperatures to below 150 degrees Celsius,” Norris says. “Until now, this has been impossible to do for conveyor rollers due to the sheer quantity of bearings that needs to be tracked and as a result, underground coal mines would routinely break their statutory obligations. Smart-Idler now provides them a way to ensure that no conveyor roller bearing overheats to these limits and goes unnoticed.”
Automation and condition monitoring technology could revolutionise conversations concerning conveyor safety over the next few years as the pace of mining’s digitisation continues to pick up and companies such as Vayeron and Sandpit are well met to meet these safety needs.
This article also appears in the Apr-Jun 2019 edition of Safe to Work.