Grinding Wheels - 8: Identification
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|Each grinding wheel comes with a paper label glued to its face. The label provides much information concerning the composition of the wheel.
The system is a series of numbers and letters which codify the composition of the wheel. The first letter indicates the type of abrasive used, using the letter A for Aluminum Oxide or C for Silicon Carbide. Next the manufacturer of the wheel will indicate the grain size, with appropriate numbers indicating a coarse, medium, or fine range. The grade is indicated in alphabetical form, with the softest grade being the A end of the alphabet, and the Z being the hardest.
Structure is indicated by a numerical rating, but its use is optional. Finally the bond type is indicated by an abbreviation of the type of bond used, V for vitrified, S for silicate, etc.
Wheels sometimes have different colors and can be representative of the type of wheel. If the Norton Company is used as a reference, the following color codes would apply for the best materials and processes for each wheel: