Improvements in grinding stones or wheels particularly adapted for grinding wood pulp

摘要

238,176. Norton Co., (Assignees of Greenwood, W. W.). Aug. 6, 1924, [Convention date]. Wheels.-In an abrasive stone or wheel particlarly adapted for grinding wood-pulp and of the kind in which a number of abrasive segments are mounted closely adjacent to each other upon a rotatable member, the segments are made of hard bonded material and a filler is provided in the crevices between the adjacent segments, the filler being of different material from that of the segments or of the bonding-material thereof of such a nature that it will wear away under normal grinding operation at substantially the same rate as the wheel segments wear. The abrasive segments are made of artificial abrasive grains bonded by vitrified ceramic material. The filling-material is of tough and durable material and adapted to protect the corners of the segments from breakage; it may be Babbit or other lowmelting material which is adapted to enter the surface pores of the segments and unite them into an abrading-ring. As shown, Figs. 3 and 4, the segments 16 are mounted on a drum 12 connected to a hub 11 by a central web 13 and radial flanges 14. Each segment has an inner dovetailed portion 18 held in place by interfitting parts carried on the drum 12. Wedge-blocks 20 may be fitted in the grooves 21 between the portions 18 and be operated by means of studs 22 which pass through the drum and are provided with nuts 23 on their inner ends. Each segment is provided with a smooth facing or shoe 28, preferably of lead or other soft metal, to fit against the drum and wedge faces. An alloy composed of 91 per cent. tin, 4.5 per cent. antimony, and 4.5 per cent copper may be run into the crevices between the segments and into the space 30 between the segments and the wedgeblocks 20. The segments are made of artificial abrasive grains such as silicon carbide or crystalline alumina bonded bv a vitrified ceramic material into an open porous structure. A bonding-composition consisting of feldspar, clay, and ground quartz may be emjloyed. For a wide wheel, two or more rows of segmental blocks are arranged with staggered joints.