The industrial test and thought about the large diameter horizontal long drilling hole

It is introduced that the industrial test about large diameter horizontal long drilling hole, and put forward personal viewpoint to question met on test. Totally four hole had been executed using directional drilling technology. Two drilling hole depth is more than 800 m, and the longest drilling hole is 865 m in length, drilling hole diameter is up to 153 mm, the highest sheet drilling speed is up to 28 m/h.