ROCK BIT HAVING A LABYRINTH SEAL/BEARING PROTECTION STRUCTURE

A drill tool includes a cone mounted for rotation on a bearing shaft that extends from a bit head. The cone has a first planar base surface opposed to a second planar base surface of the bit head. A first annular groove is formed in the first planar base surface, and a second annular groove is formed in the second planar base surface. The first and second annular grooves are at least partially aligned with each other. The combination of the first and second annular grooves form a first annular gland. A protector ring is inserted into the first annular gland, and functions to divide a fluid path between the bearing shaft of the drill tool and an external environment into a plurality of parallel fluid paths that pass around the protector ring. Each parallel fluid path includes a convolution defined by a plurality of fluid direction changing corners.