Abstract: Idle roller assembly suitable for use in trough type belt conveyors is provided having an elongate shaft and spaced apart first and second roller bearing assemblies, each having mounted thereabout an annular hub. A cylindrical tubular roller is mounted to and spans between the spaced apart hubs forming a conveyor support surface. One of the roller bearings affixed to the shaft in a fixed axial position while the other bearing outer race is capable of moving axially sufficiently to accommodate thermal expansion of the cylindrical tubular roller during use. Seals are provided, outboard of each of the hub members between the hub and the adjacent shaft to isolate the bearings from the environment.