A sleeve bearing device is disclosed for supporting a worm gear journal disposed within a casing of a valve actuator. The device includes a ring shaped portion having an inboard and an outboard end. The outboard end of the ring shaped portion defines a radially outwardly extending flange which cooperates with the casing for inhibiting axial movement of the ring shaped portion relative to the casing. The ring shaped portion is of cylindrical configuration and defines an inner and an outer surface. The inner surface of the ring shaped portion bearingly supports the worm gear journal. The outer surface of the ring shaped portion cooperates with the casing, the casing defining an annular groove. The annular groove is disposed coaxially relative to the ring shaped portion, the annular groove being located adjacent to the outer surface of the ring shaped portion and between the inboard and the outboard ends of the ring shaped portion. A sealing ring is disposed within the annular groove, the sealing ring sealing the outer surface of the ring shaped portion relative to the casing.