Metal-face-seal rock bit

摘要

A bit is provided having at least one leg extending downwardly and inwardly from the bit body. A cutter cone is rotatably mounted on a shaft extending inwardly from the lower portion of each leg. The annular space defined by the base of the shaft and the inner surface at the base of the cone forms a seal gland. An elastomeric o-ring sealingly engages an inner surface of the cone and a first rigid ring which rotates with the o-ring and cone. The o-ring energizes the first rigid ring for sealingly engaging a second rigid ring mounted to the leg of the bit near the base of the shaft. The second rigid ring is secured to and seals against a surface at the base of the shaft and is held stationary relative to the surface. A lubricant passage for lubricating the seal is pressurized by the drilling fluid pressure in the center of the bit body.