MICO drills down deep into improvement project

Our Mount Isa Copper Operations (MICO) team has modified their underground drill rigs to allow them to be started remotely, improving safety and reducing time offline.

Drill rigs, or jumbos as they’re known across the business, are an essential piece of modern mining equipment used for underground development and production. They drill holes into the hard underground rock in order for explosives to be inserted and fired to optimise the extraction of mineral bearing ore.

Drill rigs are hybrid machines in that they can run on both diesel and electrical power. Generally, they will use their diesel motors to move along and position themselves underground, while when they are drilling in-situ they rely on electrical power.

When relying on electrical power, they are connected via a long trailing cable to Distribution Control Boards (DCBs), which are permanent fixtures underground that supply the high level of power needed to run the drills.

A drill rig, also known as a jumbo, getting serviced in an underground workshop.

Until now at MICO, every time they needed to power up the jumbo, operators were required to travel back to the DCB to manually start them up. This start-up at the DCB was also required in cases where the jumbo may have lost power due to an electrical trip as well as when pre-starting the rig, which further increased downtime.

Understandably, this cumbersome process caused a considerable amount of downtime, and meant that each respective drill was offline until personnel made their way to the DCB to initiate the start-up process.

As part of a Queensland Metals improvement project led by GFM High Voltage Electrical Supervisor, Robbie Rendall, MICO has undertaken wiring modifications to the drills and DCB’s, which allow them to be started remotely from the cabin in the jumbo.

This means the jumbo can be powered up anywhere as long as a trailing cable is connected to the DCB and brings them in line with how drills operate at George Fisher Mine and Ernest Henry Mining.

Trailing cables are used to connect drill rigs to the DCBs as can be seen with this underground jumbo at George Fisher Mine.
Workers are now able to remotely start up their drill rigs utilising more of their extension cables.

Mount Isa Mines High Voltage Electrical Superintendent, Peter Ferguson, says this improvement will reduce drill rig downtime.

“The project has provided greater flexibility to our underground mining equipment by providing the ability to seamlessly move the machines between our assets to where they are most needed,” says Peter.

“The introduction of the remote start-up system also creates some substantial safety improvements for our underground workers.”

“Employees no longer have to regularly travel to and from the DCBs to start up and they now do it from the safety of their jumbos.”

Jumbo operators ensure an efficient firing pattern is followed when drilling holes.

“The operator has the ability to de-energise the trailing cable during the rigging and de-rigging process and this helps eliminate the potential for an electrical incident while increasing the efficiency of their pre-starts.”

“We also have the opportunity to utilise more of our extension cables so our jumbos can be moved further from the DCBs.”

It is improvements like these, Peter says, that are really important in learning safer and more effective ways in which to operate.

“We have the same drill rigs and DCBs at MICO that are in operation at George Fisher Mine, so that makes it much easier to coordinate our training courses and packages for our employees across both sites.”

“The electrical teams at George Fisher Mine and MICO worked collaboratively to bring this project on board and there was a lot of knowledge sharing between the departments.”

“We are looking forward to operating as efficiently as possible into the future,” says Peter.