The efficiency challenge
With a resource base of 7.5 million ounces of gold and 67 million ounces of silver, Martabe Mine is one of the largest gold mines in the world. Located in North Sumatra, Indonesia and managed by PT Agincourt Resources, the mine commenced operations in July 2012. It has an annual operating capacity of 4.5 Mt of processed ore, 260,000 ounces of gold and 2.1 million ounces of silver.
Every seven weeks, a shutdown of the SAG Mill was scheduled to assess and maintain the steel mill liners and screen media. Yet the metallurgy team at the mine observed that the feed-end blank panel’s mean time to failure was a maximum of four weeks. Depending on the mill discharge grate wear, sometimes only three weeks wear-life was achieved. This meant, even with the original seven-week shutdown frequency, the SAG Mill faced unplanned downtime and production loss to allow the feed-end blank panels to be changed.
However, the mine’s ultimate goal was to extend the shutdown to 16 weeks. Therefore, changes needed to be made.