摘要 |
A rotary drill tool for cutting rock comprising a set of journal legs that rotatably mount rotating cone shaped cutters via respective bearing assemblies. A fluid supply passageway (501) extends through the journal legs to provide a cooling and cleaning fluid to the bearings (204, 205, 206) in use. A by-pass passageway (900) extends through a base region of the spindle that mounts each cone cutter and is provided in direct fluid communication with the supply passageway to divert the fluid to a base region of the bearing assembly. |