Question

During grinding of a C.I specimen of 10 mm wide and 100 mm long with A 27 K 6V grinding wheel of 300 mm dia and 25 mm wide, the wheel has undergone a radial wheel wear of 50 microns after removing a layer of 5 mm. The grinding ratio is

• A. 21.2
• B. 2.12
• C. 42.4
• D. 4.24

Answer 1

The correct option is D 4.24

$\text{Volume of grinding wheel wear}$
$\begin{array}{cc}& =\frac{\pi }{4}(D_{Initial}^2-D_{Final}^2)\\ & =\frac{\pi }{4}\left(\right(300{)}^2-(300-100\times {10}^{-3}{)}^2)\\ & =\frac{\pi }{4}({300}^2-{299.9}^2)\times 25\\ & =1177.9m{m}^3\end{array}$
$\text{Volume of material removal of workpiece}$
$\begin{array}{cc}& =l\times w\times d\\ & =10\times 100\times 5=5000m{m}^3\\ \text{Grinding ratio}& =1177.9/5000=4.24\end{array}$