Grade of Grinding Wheel   A "grade" does not refer to the hardness of abrasive grain or bond itself. It indicated the binding degree of weakness or strength (also known as "hardness") of the bond, which sustains abrasive grains   Binding degree increases in alphabetical order according to the given grade. A grade is a depth expressed alphabetically, when applyinga fixed load and rotation to a carbide bit of uniform shape on the flat surface of the grinding wheel.   It is most important in selecting a grinding wheel to adjust the grade by taking into consideration the hardness of the workpiece to be ground, peripheral wheel speed and other operating conditions.   Grade Table Super soft A,B,C,D,E,F,G Soft H,I,J,K Medium L,M,N,O Hard P,Q,R,S Super hard T,U,V,W,X,Y,Z