High Speed Grinding Wheel Designs

Resin bonded wheels are capable of higher speeds (Fup to about 16,000 fpm) than vitrified wheels (F up to about 85,000 fpm). This is because even though a resin bonding material has lower strength, it has greater ductility and an ability to relieve points of local stress concentration by plastic flow. 

Chip storage space may be increased by use of a coarser grit size and less bonding material. However, both of these lower the tensile strength of the wheel and thus offer only a very limited solution to the chip storage problem. In order that safety not be sacrificed in order to increase productivity, it is a Federal requirement that the maximum surface speed of a grinding wheel be limited to 2/3 the speed at which the wheel disintegrates due to brittle fracture. This provides a factor of safety based on fracture stress of (1.5) = 2.25. 

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