Down-the-hole drilling rigs can drill holes in medium-hard or above (f≥8) rock. Like the rock drill, it has the rock drilling process of impact, rotation, ballast removal and propulsion, and it belongs to the impact-rotation drilling.

Like the external rotary rock drill, it has an independent rotary mechanism and an impact mechanism. The difference is the impact mechanism of the down-the-hole drilling machine - the impactor is installed at the front end of the drill pipe, dives into the bottom of the hole, and continues to advance with the extension of the drill hole. The down-the-hole drilling rig is named after the impactor dives into the bottom of the hole.

DTH drilling rigs are not like rock drills, the energy loss increases with the length of the drill rods, so deep holes and large holes can be drilled;

When applied to underground drilling, compared with the rock drill, the noise of the working face is greatly reduced due to the impactor working deep into the hole;

When applied to open-air drilling, compared with steel rope impact drilling rigs, the drilling speed is increased by 2~3 times, the degree of mechanization is higher, the auxiliary operation time is less, and the operation rate of the drilling rig is improved;

The down-the-hole drilling rig is light in weight, flexible in maneuverability, low in investment cost, especially capable of drilling inclined holes, which is beneficial to control the grade of ore, increase the stability of the slope, eliminate the foundation, and improve the blasting quality.