These wheels are used for the direction change and the guidance of the enameled wire. We have general wheels and ceramic wheels.The ceramic circle inside is made by the fine porcelain. There is a high-speed bearing in the ceramic circle which can assure the lag sliding distance between the wire and the circle is no more than 0.2mm, thus the wire insulation film has been protected and the beating of the wire has been controlled within a certain small scope. The sidewalls of the ceramic roller can prevent the jump of the wire during the winding, and stabilized the tension.