EXCLUDER RING FOR EARTH-BORING BIT.

摘要

An elastomeric seal ring is located between each bearing pin and each cone of anearth-boring bit. An excluder ring or band is imbedded within the inner diameterof the seal ring. A portion of the inner diameter of the seal ring as well as the excluderring are in dynamic sealing contact with the bearing pin. The excluder ring maybe harder and more wear resistant than the seal ring. The excluder ring may havelubricating properties. An outer excluder ring may be located on the outer diameterof the seal ring for engaging the cone to resist rotation.