Various Drilling Rigs manufacturer / supplier in China, offering High Work Efficiency, Capable of Drilling to Depths of 200m, 300m, 400m, and 500m: Reverse Circulation Drilling Rig., The Intelligent, Multi-Functional and Highly Reliable Large-Diameter Zb350s Water Well Drilling Rig Capable of Drilling 100m and 200m Wells., 500-Metre Mining Exploration and Mining Using a Tracked Reverse Circulation Drill Rig and so on.