A gear-grinding multilayer grindstone includes a rough machining portion and a finish machining portion that are disposed adjacent to each other on a rotational axis. The rough machining portion includes a first core and a rough machining grindstone that is held on the first core. The finish machining portion includes a second core that is adjacent to the first core, and a finish machining grindstone that is held on the second core. The first core and the second core are fixed to each other, without the rough machining grindstone and the finish machining grindstone being fixed at least at outer peripheral portions thereof to each other.

The disclosed technology includes an abrasive cutting tool having a plurality of segments arranged around a periphery of the cutting tool. The plurality of segments can include a first segment having a first portion having a first concentration of abrasive material, and a second portion having a second concentration of abrasive material. The second concentration can be less than the first concentration. The cutting tool can have a second segment having a third portion having a concentration of abrasive material that can be similar to the concentration of the first portion, and a fourth portion having a concentration of abrasive material that can be similar to the concentration of the second portion. The first portion and the second portion can be reciprocally arranged in relation to the third portion and the fourth portion around the periphery of the cutting tool.

The disclosed technology includes an abrasive cutting tool having a plurality of segments arranged around a periphery of the cutting tool. The plurality of segments can include a first segment having a first portion having a first concentration of abrasive material, and a second portion having a second concentration of abrasive material. The second concentration can be less than the first concentration. The cutting tool can have a second segment having a third portion having a concentration of abrasive material that can be similar to the concentration of the first portion, and a fourth portion having a concentration of abrasive material that can be similar to the concentration of the second portion. The first portion and the second portion can be reciprocally arranged in relation to the third portion and the fourth portion around the periphery of the cutting tool.

A grinding wheel includes a disc-like member and a grinding layer disposed on an outer peripheral surface of the disc-like member. The grinding layer includes a plurality of circumferentially-divided grinding chips which are divided in a circumferential direction. Each of the circumferentially-divided grinding chips is formed by arranging a first grinding chip and a second grinding chip in the axis direction, the first grinding chip and the second grinding chip having different properties. A boundary portion between the first grinding chip and the second grinding chip of at least three circumferentially-divided grinding chips continuously arranged in the circumferential direction are arranged toward a predetermined direction in the axis direction in the order in which the circumferentially-divided grinding chips are arranged.

A grinding wheel includes a disc-like member and a grinding layer disposed on an outer peripheral surface of the disc-like member. The grinding layer includes a plurality of circumferentially-divided grinding chips which are divided in a circumferential direction. Each of the circumferentially-divided grinding chips is formed by arranging a first grinding chip and a second grinding chip in the axis direction, the first grinding chip and the second grinding chip having different properties. A boundary portion between the first grinding chip and the second grinding chip of at least three circumferentially-divided grinding chips continuously arranged in the circumferential direction are arranged toward a predetermined direction in the axis direction in the order in which the circumferentially-divided grinding chips are arranged.

The present disclosure provides improved rail grinding tools. Precision-shaped grains (PSGs), such as PSGs manufactured by 3M® company, provide significant performance improvement in resin-bond and vitrified bond grinding wheels. The use of PSG improves the performance of portable bonded wheels and precision grinding wheels, such as resin bond roll grinding wheels, flute grinding wheels, vitrified gear grinding wheels, cylindrical grinding wheels, and surface grinding wheels. The formation and composition of (e.g., monolithic) and multiple-layer PSG grinding tools described herein provides improved performance of rail grinding tools.

An abrasive grinding wheel (20) comprising an annular body (200) defining an abrasive front face (202) at least partly made of a layer of an abrasive mixture (21) and an opposite rear face (203), which grinding wheel (20) comprises an annular damping element (23) made of a resilient yielding material and fixed to the annular body (200), wherein the damping element (23) comprises a first face (231) facing towards the abrasive front face (202) and an opposite free second face (232) which defines at least a portion of the rear face (203) of the annular body (200).

An abrasive grinding wheel (20) comprising an annular body (200) defining an abrasive front face (202) at least partly made of a layer of an abrasive mixture (21) and an opposite rear face (203), which grinding wheel (20) comprises an annular damping element (23) made of a resilient yielding material and fixed to the annular body (200), wherein the damping element (23) comprises a first face (231) facing towards the abrasive front face (202) and an opposite free second face (232) which defines at least a portion of the rear face (203) of the annular body (200).

The present disclosure relates to abrasives surfaces located on an outer diameter of a grinding wheel to provide grinding characteristics of both coarse and fine abrasive textures. The grinding wheel has a coarse abrasive portion located at one disclosure uses a transition band formed at an interface between the abrasive surfaces, that has an abrasive coating with a gradual change in texture from a coarse surface to a fine surface.

The present disclosure relates to abrasives surfaces located on an outer diameter of a grinding wheel to provide grinding characteristics of both coarse and fine abrasive textures. The grinding wheel has a coarse abrasive portion located at one disclosure uses a transition band formed at an interface between the abrasive surfaces, that has an abrasive coating with a gradual change in texture from a coarse surface to a fine surface.