As well as setting the pace for other Australian longwall mines in overall production terms, Newlands continues to show the way on roadway development. According to equipment supplier Joy Mining Machinery, its continuous miners and shuttle cars are helping the Queensland mine maintain its record development pace.
As recently as December last year the mine achieved 106.2m of advance in a 12 hour period and 80m in a 10 hour stint. These impressive results followed the setting of a new best shift record for Australian mines in November 1998, when Newlands recorded 82.7m of development in an eight hour shift.
Development work at the mine started with a secondhand 12CM30. This was superseded early in 1998 with the delivery of new 12CM12 continuous miners and 15SC32 cars.
The mine's coal seam extraction height and width in roadways is 3.5m and 5.2m, respectively. The continuous miner and shuttle cars develop a twin entry gate road system for longwall panels, installing four 2.1m roofbolts and W-strap every 1.5m of advance and one rib bolt per strap on each side.
Joy says the 12CM12 miners feature two 170kW cutter motors and are fitted out with three bolting rigs on each side of the machine: two roof bolters and one rib bolter. Crews are made up of 10 personnel, including a deputy, an electrician, a mechanic, and seven operators. They all work very closely together, loading up their own materials on the surface to operate the 12CM12 at the face.
At the time the records were set the crews worked three eight-hour shifts per day, five days a week. The mine has since switched to a new roster which allows production seven days a week, with 28 hours a week allowed to maintain the equipment.
