Vitrified bond CBN wheels are used for centerless grinding of various types of bearing rollers, injection nozzles, pump parts, etc. Since CBN has excellent grinding characteristics, vitrified bond CBN wheels need not be as large as conventional abrasive wheels. However, due to their comparatively large width and diameter, and in order to maintain wheel balance essential for high-speed revolution, a ceramic core is used to reduce overall weight and prevent thermal deformation.