1.Tungsten Carbide Coal Mine Bits Manufacturer 2.the head of tungsten carbide tip is sintered by vacuum 3.dry-type and wet-ty Tungsten carbide coal Mine Bits,coal mining cutter teeth,coal bitsThe coal mine bits are mainly used in coal and mine drilling,have dry-type and wet-typeDimension:25,27,28,29,30,32,36,42, Tungsten Carbide Coal Mine Bits