Milling

Types of Milling operations

1. Milling Processes





Radha.R, Assistant Professor (Sr), VIT University, Chennai

2. Milling
•Milling is a metal removal process by means of using a
rotating cutter having more cutting teeth feed against the
workpiece.
•Milling machine is one of the most versatile conventional
machine tools with a wide range of metal cutting capability.
•Many complicated operations such as indexing, gang milling,
and straddle milling etc. can be carried out on a milling
machine.

3. Types of Milling Machines and parameters:


Based on cutter rotation

1. Peripheral Milling
2. Face Milling

Based on Cutting direction
1. Up Milling
2. Down Milling

Based on arrangement
1. Horizontal Milling Machine
2. Vertical Milling Machine

Cutting parameters:
•Spindle speed
•Feed / cutter tooth or Chip load
•table feed
•depth of cut
•rotating direction of the cutter

4. Peripheral Milling vs. Face Milling
•Peripheral milling
–Cutter axis is parallel to surface being machined
–Cutting edges on outside periphery of cutter


•Face milling
–Cutter axis is perpendicular to surface being milled
–Cutting edges on both the end and outside periphery of
the cutter

5. Two forms of milling:
(a)peripheral milling, and (b) face milling

6. Up Milling and Down Milling

7. Horizontal Milling Machine

8. Vertical Milling Machine

9. Milling operations

10. Milling Cutters

11. •Plain milling cutters




•Face milling cutter
Slitting cutters
Helix angle 25
0

Helix angle 45-60
0
Helix angle 45
0

12. Milling Operations
a) Slab milling b) Face milling c) End milling
Arbor
Arbor
Cutter
Spindle
Spindle
Shank
End mill
d) e)

13. Pocket Milling
Contour Milling

14. Cutting conditions in Milling
•Spindle speed N = v/ ∏D
•Feed rate fr = N nt f


•MRR RMR = wd fr
•Time for feed motion Tf = cutter travel/ fr
•Machining Time Tm = L+A/ fr

15. Approach allowance = A
Peripheral milling(Slab milling)

Face milling
Cutter positioned at centre Cutter is offset