Directional drilling technology and development tendency in underground mine

The paper introduced five different directional drilling technologies and stated each directional principle,technical features and application situation. The paper summarized the development progress and shortages existed in the directional drilling technology with stabilized drilling assembly and the sliding drilling technology with downhole motor applied in the underground coal mine. In combination with the available directional drilling equip ment and technology,the paper pointed out that a high strength full cable drilling tools and the wireless transmission technology suitable for undergroun d mine were the difficulty to realize a compound drilling technology. An underground information closed-loop control system and the advanced steering t ool were the difficulty to realize a rotary steering technology. A geological logging technology while the bit drilling was the difficulty to realize a geologic al steering technology. Finally,the paper pointed out that a high automation and intelligent steering drilling would be the development orientation of the directional drilling technology. Related proposals were provided to speed up the development of the directional drilling technology in the underground m ine.