摘要 |
Button inserts of a rock drilling bit are ground by positioning a grinding cup against each button insert and rotating the cup while supplying flushing fluid thereto. The flushing fluid is conducted through an axial bore of a spindle on which the grinding cup is mounted. An inner end of the spindle is mounted for rotation in a grinding head, and is rotated by a drive mechanism disposed within the grinding head. Flushing fluid is supplied to the axial bore through a flushing head mounted on the spindle at a location outside of the grinding head. The flushing head has axially spaced parts that are movable axially relative to one another under the force of flushing fluid passing therethrough, in order to establish a fluid seal. |