Question

A cutting tool fails due to flank wear while machining. It is observed that the tool life at a cutting speed of 160 m/min is 5 min, while at 120 m/min, it is 17 min. What is the approximate tool life at a cutting speed of 100 m/min?

Answer 1

The answer is:

30 minutes.

Explanation:

We are given the following information:

at 160 m/min, tool life = 5 min.

at 120 m/min, tool life = 17 min.

This means that as the speed reduced from 160 m/min to 120 m/min, the tool life increased from 5 min. to 17 min, hence the difference between the changes are:

speed = 160 - 120 = 40 m/min

tool life = 17 - 5 = 12 min.

Therefore, it can be concluded that a change of speed of 40 m/min, increases the tool life by 12 min.

40 m/min = 12 min

∴ 1 m/min = 12/40 min.

∴ 100 m/min = 12/40 × 100 = 0.3 × 100 =30 min.