Abstract: A bearing assembly for a rotating shaft uses a carbide sleeve to prevent wear and carry load. The carbide sleeves provide increased life for rotating components used in the severe environments in the oil and gas industries. Various mechanisms can couple the carbide sleeve to the rotating shaft, including keys, keyways, drive rings, reaction rings, and other members to provide particular benefits. These mechanisms allow the carbide sleeve to bear the compressive load of other components, for example, or to slide axially on the shaft, when needed.