Mill tooth tricone rock bit 1.Dia:3 1/2 ... 116,217,437,517,537,617 4.oil,water well Mill tooth Tricone ROCK Bit -TCI Tricone Bit Specifications: ... low compressive strength strength and high drillability,such as soft shale,clay and salt bed,etcHardfaced gage and all tooth surfaces.0 ... drillability,such as soft shale,clay and salt bed,etcHardfaced gage and all tooth surfaces, and a row of trimmers is added ...