... is a new product after the hot-pressed and electroplated drill bit. 1. It has a super ... speed. 3. It can be operated with low pressure and low speed. 4. It has a good gage protection ... PDC bit is mainly used for drilling soft and medium rock, and it must work under low drilling pressure, ... sand, peat, rock, mudstone, tuff, hard marl, marl and other hard sandy clay1~4 grade, 15~25°mediumlimestone, marble ...