Research and Development on Drilling Pipe Matched for Horizontal Directional Drilling in Underground Mine

According to the problems occurred in the operation process of the dilling tools matched with the imported directional dilling equipment, in combination with the certain geological deposition features of the coal mine in China and the directional drilling technical requirements, with the analysis on the working conditions f or the drilling tools matched with the directional dilling, the material optimized selection, structure optimization and the performances detection, the thread structure of t he cable central passing mode dilling pipe with large inner hole and the signal transmission device structure were set up. The high strength inner diameter 73 mm cable central passing mode drilling pipe and the matched drilling tools were successfully researched and developed.The standard of the drilling pipe detection was set up.Duri ng the industrial trial period, the inner diameter 73 mm cable central passing mode drilling pipe was applied to realize the 1 212 m depth borehole drilled with the horizo ntal directional drilling in underground mine.The real-time, high efficient and reliable signal transmission in the drilling process could fully meet the application requirem ents of the 1 000 m directional drilling with the drilling measuring system.