... operation 2.Economic drilling 3.High efficiency Hydraulic rock drill: 1. DT-60 drilling machine adopts advanced reverse circulation technology,drilling speed ... it within one hour, easy transportation, easy to disassemble the machine,. 3. Assembled just need only a few minutes, After ... speed greatly. 5. For drilling clay, loam, sand, weathered rock and a small amount of gravel areas can better play ...