An abrasive rotary tool includes a tool shank defining an axis of rotation for the rotary tool, and an abrasive external working surface. The abrasive external working surface includes a resin, and a plurality of porous ceramic abrasive composites dispersed in the resin, the porous ceramic abrasive composites including individual abrasive particles dispersed in a porous ceramic matrix. At least a portion of the porous ceramic matrix comprises glassy ceramic material. A ratio of the average porous ceramic abrasive composite size to the average individual abrasive particle size is no greater than 15 to 1.

An abrasive rotary tool includes a tool shank defining an axis of rotation for the rotary tool, and an abrasive external working surface. The abrasive external working surface includes a resin, and a plurality of porous ceramic abrasive composites dispersed in the resin, the porous ceramic abrasive composites including individual abrasive particles dispersed in a porous ceramic matrix. At least a portion of the porous ceramic matrix comprises glassy ceramic material. A ratio of the average porous ceramic abrasive composite size to the average individual abrasive particle size is no greater than 15 to 1.

An abrasive rotary tool includes a tool shank a flexible planar section positioned opposite the tool shank. The flexible planar section forms a first abrasive external surface on a first side of the flexible planar section and a second abrasive external surface on a second side of the flexible planar section. The flexible planar section facilitates abrading, corners of a workpiece across multiple angles relative to the axis of rotation for the rotary tool through bending of the flexible planar section when the abrasive external surfaces are applied to a corner of the workpiece.

Cylindrical rolling bodies, methods of producing the rolling bodies, and anti-friction bearings including the rolling bodies are disclosed. A method of producing the rolling bodies may include a) providing a spherical blank having a diameter (D) and a radius; and b) grinding the spherical blank into a cylindrical shape having a predefined diameter (d) and a length (L) that corresponds to the diameter (D) to form a cylindrical rolling body. After grinding, the cylindrical rolling body may have crowned end surfaces each having a radius corresponding to the radius of the spherical blank. Centerless cylindrical plunge grinding or centerless cylindrical throughfeed grinding may be used as the grinding method.

Cylindrical rolling bodies, methods of producing the rolling bodies, and anti-friction bearings including the rolling bodies are disclosed. A method of producing the rolling bodies may include a) providing a spherical blank having a diameter (D) and a radius; and b) grinding the spherical blank into a cylindrical shape having a predefined diameter (d) and a length (L) that corresponds to the diameter (D) to form a cylindrical rolling body. After grinding, the cylindrical rolling body may have crowned end surfaces each having a radius corresponding to the radius of the spherical blank. Centerless cylindrical plunge grinding or centerless cylindrical throughfeed grinding may be used as the grinding method.

A double-disc straight groove cylindrical-component surface grinding disc, includes a first grinding disc and a second grinding disc, rotating relative to each other; the the first grinding disc's working face is planar; the second grinding disc's surface, opposite the first grinding disc, includes a set of radial straight grooves, with groove faces of the straight grooves are the working face of the second grinding disc; the cross-sectional outline of the working face of the second grinding disc is arcuate or V-shaped or is a V-shape having an arc; during grinding, a workpiece spins inside the straight grooves, while under the effect of an advancing apparatus, the workpiece slides in translational motion along the straight grooves. The described grinding disc device has high-volume production capabilities, and the shape accuracy and size consistency of the cylindrical roller's cylindrical surface and the efficiency in machining are improved, and machining cost is reduced.