The device is the brainchild of Sandpit Innovation and it has been in development for about 18 months.

It involves fitting two rails – one on either side of the conveyor belt – and running a machine along it that can pick up the moving belt, remove the damaged idler and replace it before putting the belt back in place.

There is no need to stop the conveyor belt or for any personnel to get too close to the belt either.

In its first phase the device will be on line of sight remote operation where the operator will need to be within 100 metres of it. The second phase is a teleremote operation where the operator can be in a control room watching it operate on video screens and the third phase is full autonomous operation.

The Spidler has been successfully tested on a 15,000 tonne per hour outlet conveyor at Port Hedland.

On such a conveyor the idlers tip the scales at about 40 kilograms apiece and a square metre of unloaded belt weighs about 400kg.

Normally, when the mine or port facility takes the decision to shut down the belt for maintenance it involves a large crews who race around trying to change as many broken idlers as they can.

In some cases virtually new idlers get changed out too because they could fail before the next shutdown.

To get to the idlers the belt has to either be lifted by a crane or jacked up manually. The idlers are then removed and replaced by hand. This can involve men working at heights and on steep inclines.

In some cases the conveyor belts are on the side of mountains, with all the dangers of large drops that go with that as well as works being undertaken in snowy conditions.

The Spidler is designed to move up and down the conveyor belt, with the capacity to handle an incline of 15 degrees.

When running fully autonomously it has sensors aboard that allow it to detect a broken idler, lift the belt and change it out. The machine can even record and report idler frame and idler change out data.

It can move up and down the belt at up to 6kph. It can lift the belt in about 10 seconds and change out an idler in about three minutes.

SPIDLER v2 from Sandpit Innovation on Vimeo.

Sandpit Innovation director Aaron Carter said the idea of adding rails to a conveyor might be off putting to some but it was little different than the walkways that already had to be added.

Having the rails makes sense in terms of moving the machine up and down the belt, but it was not a completely simple solution.

“There were some pretty unique engineering problems we had to overcome to balance and distribute the weight equally,” Carter said.

“That rail is at the core of the Spidler.”

Carter said the company also envisaged having cartridges at intervals along the belt – sort of like vending machines – where the Spidler would stop and replenish its idler supply and drop off the broken ones it had removed.

“We wanted something that could ultimately be fully autonomous, be able to monitor itself and monitor idlers and traverse up and down the conveyor belt regardless of its environment,” he said.

Adding the rail could be a sticking point for some but it need not be.

“Most clients see that as having to put additional infrastructure in place,” Carter said.

“But [with] all the conveyors we’ve seen it is doable without considerable modifications to the foundations and the like.

“We’re looking at ways the machine can lay track itself to speed up the process.”

By only fixing the idlers when they require it, Sandpit Innovation hopes to greatly reduce the maintenance costs miners have to pay while also increasing plant availability.

Carter said the financial benefit of only replacing the idler rollers when needed would account for about 18% of the total financial benefit delivered from the Spidler.

The clients the company is looking at are those for whom utilisation is important.

Having the Spidler could change the way conveyor belts are designed.

For one thing, they may no longer need to have walkways fitted to them. That is quite a saving in terms of infrastructure.

If there is a need to send people out to a roller so damaged the Spidler could not replace it, they could conceivably travel out to the site on the Spidler. The machine could then act as a jack to lift the belt up. In such a case the belt would have to be stopped.

“The machine has a walkover platform on it for such instances,” Carter said.

“I liken it to the maintenance cars on a rail line.”

Other ideas that have emerged alongside the simple idler change-out function include washing down belts and possibly even dragging broken belts along to a point where they can be fixed.

“There are three key value propositions for the machine,” Carter said.

“It can increase production, extend idler life and remove the need for mass idler change-outs.

“This can lead to a payback in a matter of months. When you have major failures this payback can be measured in a matter of days.”

The prototype put to the test in Port Hedland is sitting at the Lewis Australia facility in Melbourne.

Robotics specialist Lewis is owned by Sandpit Innovation.

The device won an award at the recent Bulk Material Handling Awards which helped spark interest in it.

But will that lead to sales?

Maybe not given the risk averse nature of the mining sector.

“My personal opinion is that not many people want to be the early bird,” Carter said.

“I think there will be a lot of fast followers though.

“At the moment we recognise that there is a cost securing the early bird.

“We’re prepared to work with someone who is prepared to develop this at the right scale.”

Indeed, Carter said Sandpit Innovations was involved in negotiations at the moment but declined to divulge who those negotiations were with.

To protect its intellectual property, Sandpit Innovation has taken out a family of patents on the machine around the world.