Direction: A disc of 200 mm outer and 80 mm inner diameter is faced at a feed of 0.1 mm/rev with a depth of cut of 1 mm. The facing operation is undertaken at a constant cutting speed of 90 m/min in a CNC lathe. The main (tangential) cutting force is 200 N.
-
Assuming approach and over-travel of the cutting tool to be zero, the machining time in min is
-
- 2.93
- 5.86
- 6.66
- 13.33
- 2.93
Correct Option: A
| t = | = | |||
| 4.fr.V | 4 × 0.1 × 10-3 × 90 |
time, t = 2.93 minutes
