Equivalent wheel diameter, de, is a parameter that takes into account the conformity of the wheel and the workpiece in cylindrical grinding and gives the equivalent wheel diameter for the same contact length in a surface grinding application (i. e., de ^ ds as dw ^ ^). The plus sign is for external cylindrical grinding, while the negative sign is for internal cylindrical grinding.
d x d
de = дs ± ^ dw = workpiece part diameter
s w ds = wheel diameter
2.2.6 Active Grit Density
Active grit density, C, is the number of active cutting points per unit area on the wheel surface.
2.2.7 Grit Shape Factor
Grit shape factor, r, is the ratio of chip width to chip thickness. In most discussions of precision grinding, the product C-r is considered as a single factor that can be somewhat affected by dress conditions; but under stable grinding conditions, that is, with a fixed or limited range of dress conditions, can be considered as a constant for a given wheel specification.
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There are several key parameters that research has shown to be directly dependent on hcu:
2.2.8 Force per Grit
Grit retention is directly related to the forces experienced by the grit and these forces increase with uncut chip thickness. It can be seen that for a constant stock removal rate (ae — vw) forces are lower at large depth of cut and low table speed. Hence, a softer grade might be used for creep feed rather than for reciprocated surface grinding. A softer grade has a better self-sharpening action and reduces grinding forces.
Wheel wear can accelerate as a wheel diameter gets smaller and force/grit increases.