A rotary drilling rig is used to cut or crush through sub surfaces.  Thus, it is possible thanks to downward pressure, and the combined effects of a sharp, rotating drill bit. 

Additionally, the impact force the above-ground or down-hole impact hammer supplies to the drill bit helps the rig drill deeper and wider holes. 

The features of a rotary drilling rig worth mentioning include:

• A short leader system for use in shallow construction sites 
• The presence of modularly constructed leaders and counterweights
• The presence of strong, lightly designed steel Kelly bar tubes
• Tailored, large, spaced pumps and valves that are easy to maintain
• Special drilling attachment for use with anti-seismic piles
• Modern air-conditioning that improves the operator’s comfort through better airflow
• Control system with multiple program and control options 
• Providing the operator with optimized vision field and noise protection