Rock Drilling Tools
Down-the-hole drilling tools
Large diameter DTH drilling tools were originally developed for projects requiring large boreholes, such as oil and gas, coalbed methane, and geothermal drilling. With their high-efficiency rock-breaking capability, these tools have since been widely adopted in construction and foundation engineering, effectively overcoming the limitations of rotary drilling rigs and long auger systems in hard rock conditions.
Since the introduction into pile foundation construction, large diameter DTH tools have delivered significant improvements in drilling efficiency. Boreholes that traditionally required weeks or even months to complete using conventional impact hammers can now be completed within hours with DTH systems.
In hard rock formations, such as granite, and in weathered rock layers, rotary drilling rigs often require DTH drilling assistance to operate effectively. Under these conditions, large diameter DTH drilling tools consistently achieve several times the productivity of rotary drilling and long auger methods.
Large diameter DTH drilling tools consist of integrated DTH hammer and bit systems, combined with modified rotary drilling rigs or long auger rigs.
Component Display of the Integrated DTH System
Large diameter DTH drilling tools are designed with large-section cuttings discharge channels and erosion-resistant structural components. These features enable stable, high-efficiency drilling in hard rock, boulders, and complex formations. Under typical conditions, daily penetration rates of 30-50 meters can be achieved, while the risks of tool sticking and operational failures are significantly reduced.
Each drilling bit is designed with: large-section cuttings discharge channels, wear-resistant surface coatings, multi-stage rock-breaking button arrangements. These features are optimized for deep foundation applications with diameters ranging from 300 to 1200mm, enabling high penetration rates in strongly weathered rock and boulder formations.