Selection and application of drill bit for directional drilling in underground coal mine

According to the characteristics of directional drilling in underground coal mines,the general requirements of supporting bit were proposed,and the types and features of the currently used bit were introduced,then three directional bits of different crown were introduced about applicability and selection rule in detail,and the note of bit used correctly was summarized,providing a reference for selecting and using bit reasonably for directional drilling in underground coal mines.