Question

A steel flat surface of 150 mm is to produced by a horizontal axis milling machine where spindle speed is 65 rpm. The milling cutter has 8 teeth, 100 mm diameter and the machining time assuming that the entire stock can be removed in one pass and depth of cut 2 mm and feed rate of 0.15 mm/tooth is________sec

• A. 136.92

Answer 1

The correct option is A 136.92
Machining time $=\frac{L}{f_1\times Z\times N}$

Approach distance,

$A=\sqrt{d(D-d)}=\sqrt{2(100-2)}=14mm$

$L=150+2\times 14=178mm$

$T=\frac{178}{0.15\times 8\times 65}=2.28min=2.28\times 60=136.92sec$