GB385328A - Improvements in articles of bonded granular material and methods of making the same - Google Patents

Abstract

385,328. Moulding abrasive, porous, &c. materials. NORTON CO., New Bond Street, Worcester, Massachusetts, U.S.A. June 19, 1931, No. 17849. Convention date, June 19, 1930. [Class 87 (ii).] Articles of abrasive material, such as silicon carbide and crystalline alumina, are made by mixing together definite proportions of abrasive and bonding materials and then compressing a definite weight of the mixture to a predetermined volume. Fig. 8 shows the moulding apparatus in which the descent of the ram 23 of the hydraulic press is limited by interchangeable gauge blocks 20 engaging the top of the mould. The invention is applicable specially to the manufacture of grinding wheels, the object being to duplicate wheels having standard abrasive qualities without the necessity of employing an individual test to each finished wheel, but it may be used in the manufacture of porous materials such as filterplates or for tiles and the like. Reference is made also to the production of series of standard grinding wheels, each showing the same difference in hardness and grinding qualities from the next in the series, by keeping the volume percentage of the bond constant throughout the series and progressively varying the quantity of abrasive or alternatively by keeping the amount of abrasive constant and progressively varying the quantity of bond.