While the Bowen Basin mine produced its first longwall coal back in September, the maingate, trunk, drift and stockpile conveyor systems were all commissioned in mid-March.
The second coal handling and preparation plant was ready on March 23 while the overland conveyor systems were online on March 31.
Vale said the $A480 million project completion was delayed by about five months but the total execution took only 23 months, “a major achievement when compared with similar projects”.
“The expansion project is now essentially completed and fully functional, except for some punch list items and the water/drainage management associated with the surface conveyors, which will be addressed as soon as possible,” the company said.
During the past months, Vale also upgraded the site substation and transmission lines, added new ventilation fans, and purchased continuous miners, shuttle cars and other underground equipment.
The site also welcomed a new workshop along with administration buildings and other surface infrastructure.
Of an estimated 1.2 million man-hours in constructing Carborough Downs, only one lost-time injury event was recorded at one of the four subcontractors.
The longwall set-up includes 149 1200-tonne capacity Tagor roof supports with Tiefenbach electro-hydraulic control systems. The supports have a working height of 3.5-5.3m.
The 300m armoured face conveyor and beam stage loader were supplied by Inbye Mining Systems and can clear 4500t of coal per hour.
The Eickhoff SL1000 shearer with twin 2.6m-diameter cutting drums can cut up to 4500tph. It is the first SL1000 model installed in Australia.
The longwall system also incorporates one of the first commercial installations of LASC (Longwall Automation Steering Committee).
The automation package comprises a shearer position monitoring system, shield control automated face alignment module, and the shearer control INS-based automated horizon control module.
The longwall will cut 4.5m of the 5.5m-high Leichhardt seam, traversing a 300m-wide face. Longwall blocks will be 1700m long.
Vale’s Carborough Downs joint venture partners include Nippon Steel, POSCO, Tata Steel, JFE Steel and JFE Shoji.