Robit’s precision drilling solutions have proven their effectiveness in the La Arena open-pit mine, located high in the mountains of northern Peru. During testing, both Robit hammers and bits demonstrated superior performance compared to competitors.
La Arena, which extracts both gold and copper, is situated along one of the world’s largest porphyry copper-gold belts—a part of the Andean metallogenic zone known for producing major deposits throughout South America. As of late 2024, Zijin Mining owns the site.
The geology at La Arena poses a challenge for drilling due to its hard volcanic and intrusive rocks, which are highly abrasive and tough on equipment. These conditions require precise blasting techniques; the mine uses pre-splitting to maintain stable pit walls and predictable bench shapes. Pre-splitting involves drilling an exact row of holes before the main blast to create a clean fracture plane, reducing excess breakage and improving stability.
Spain-based Acciona, an international mining contractor, carries out the pre-splitting at La Arena using 4-inch (102 mm) down-the-hole hammers paired with 5-inch bits. Because tool wear has long been an issue in these abrasive rocks, Acciona conducted comparative tests to find equipment that would last longer under such harsh conditions.
In mid-2025, Robit was invited to participate in these trials. The tests included Robit’s H4 Marathon hammer with a TD40 shank and three different bit designs. Robit’s DTH Drillmaster, Renato Castro, oversaw the process, ensuring proper use and collecting performance data from June to July 2025.
Robit reports that the results were clear: the H4 Marathon hammer lasted for a total of 4,740 drilled meters, surpassing the competitor’s 3,100 meters. The drill bits showed similar results, with Robit’s averaging 140 meters per bit versus the competitor’s 65 meters. Among the tested designs, those with convex faces and Extreme Carbide gauge inserts offered optimal durability and penetration.
Following these results, Acciona is considering more bit designs with Robit—particularly Extreme Carbide models—to further lower costs and boost productivity. The Marathon hammer impressed Acciona with its longer lifespan and about 30% faster penetration rates compared to competing products.
Robit summarized the outcome by stating that these successful trials are not only a technical achievement but could also lead to a long-term partnership.
