Summer 2012. From Ground Water Canada magazine.

Rockmore International has released the first DTH hammer in its emerging Deep Hole series, the ROK 500DH. As a five-inch-class hammer, the 500DH is targeted to drill 140 to 152-millimetre (5.5 to 6-inch) diameter holes. Designed to increase drilling effectiveness and efficiency in deep hole applications, the ROK 500DH incorporates engineering advancements for drilling and DTH applications such as geothermal, exploration, water-well, and other mining and construction sectors.

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