... exploration 4,Drilling rod diameter 50 HGY-300 soil sampling Drilling MachineIt is widely used in the construction of ... , Iran, South Korea, Costa Rica etc.Features of soil sampling Drilling Machine:1) Wide range of suitable rotary speed to ... , transmission case and shifting structure. Technological Data of soil sampling Drilling Machine ModelHGY-300 Drilling MachineDrilling depth( m)300Drilling rod ...