Question

In a shaping process, the number of double strokes per minute is $30$ and the quick return ratio is $0.6$. If the length of the stroke is $250mm$ the average cutting velocity in $mm/min$.

• A. $3.0$
• B. $4.5$
• C. $7.5$
• D. $12.0$

Answer 1

The correct option is D $12.0$

Double strokes per min $=30$
Quick return ratio: $M=0.6$
Stroke length: $L=250mm$
Average cutting velocity
$=L.N(1+M)$
$=30\times 250(1+0.6)=12.0m/min$