Idler Drums

The vast majority of idler drums used in cast link belt furnaces today are eleven inches in diameter and are smooth on the contact surface. Because their main function is to support the cast link belt on the charge end of the furnace and provide “take-up” pressure to the belt, the smooth surface is desired. If the belt is not stretched more on one side than the other, it should remain centered over the idler drum. If the belt is not uniform, if some hearth rolls are not aligned perpendicular to the belt or if some hearth rolls are not level, the belt will track to one side or the other. This can only be seen if the idler drum is smooth, thus it is the warning alarm that something is not right and must be fixed.
Some furnaces are