Speaking at the Conveyors in Mining conference in Perth, International Power Hazelwood asset manager Peter Brimblecombe explained that when the operation decided to move into its west field, moving the conveyors proved an ambitious task.

Thirty-six conveyors of mixed 1200mm and 1400mm width and operating speeds of 5.4m and 6.1m per second were evaluated, overhauled and upgraded over a six-year period while the mine ensured a regular supply of coal to the power station.

Brimblecombe said for the first time in 30 years, and for possibly the only time ever, the company was able to completely evaluate the system, an opportunity he described as invaluable.

He said the belt life ranged from less than a year to 24 years, while some of the mine's electrics and safety devices required refitting to comply with industry standards.

Of priority during the move was ensuring the best efforts in standardisation, compliance with Australian standards, capacity, spill, levels of routine maintenance and monitoring capacity.

Among the parts needing an overhaul were the impact idlers that were fitted with soft loading shoots in a bid to eliminate spillage and jams on the system.

The whole system was elevated in the move, allowing for mechanical clean-up of spills and easier access for maintenance.

Brimblecombe said the decision to raise the system had been well received by crews onsite, as was the decision to install SCADA monitoring software to allow better evaluation of the conveyors' performance and remote fault finding on the system.

"The SCADA system means rather than driving 20 minutes into the mine to find the problem we can see it from the office - unfortunately the crews like the system so much they won't work without it," he said.

Among the discoveries revealed in the exercise was the need to replace and rehouse some of the system's electrical system, replace guarding and overhaul the head ends to handle the load.

"Some of these belts were installed decades ago when we were moving far smaller loads so we've had to scan the belts and looked at the drivers and a few of them needed a lot of work," Brimblecombe said.

"But while we had the system in pieces we thought there was no better time … to do a total audit and get it right."