1.PDC coal mining tools 2.ore mining, many type 3 ... steels (Integral Drill Rods)Shank H22x108mm, H19x108mm, standard hex. Bit diameters include 20-42mm.2. Tapered drilling tools (Tapered Drill ... , Ballistic and Conical. (Threaded R32, R38, T38, T45, T51 ; bit diameter: 45mm-127mm);Couplings sleeves- manufactured with a middle stop ... Rod, Cross bits, button bits and X-type bits etc). PDC coal mining tools