Question

A through hole is drilled in an aluminum alloy plate of 15 mm thickness with a drill bit of diameter 10 mm, at a feed of 0.25 mm/rev and spindle speed of 1200 rpm. If the specific energy required for cutting this material is 0.7 $N-m/m{m}^3$, the power required is_____(round off to two decimal places).

• A. 274.89

Answer 1

The correct option is A 274.89
Power required specific energy consumption = MRR
Specific energy consumption
$=0.7Nm/m{m}^2=0.7J/m{m}^2$

$MRR=\frac{\pi d^2}{4}\times fN$

$=\frac{\pi \times {10}^2}{4}\times 0.25\times 1200m{m}^2/min$

$=23561.94m{m}^3/min$

$=392.7m{m}^3/s$

$\therefore Power,P=0.7J/m{m}^3\times 392.7m{m}^3/s$

$=274.89J/s=274.89W$