Post on 06-Sep-2015
description
Chapter 24
Machining Processes: Milling, Broaching,
Sawing, Filing, and Gear Manufacturing
Milling Cutters and Milling Operations
Some basic types of milling
cutters and milling operations.
(a) Peripheral milling. (b) Face
milling. (c) End milling. (d)
Ball-end mill with indexable
coated-carbide inserts
machining a cavity in a die
block. (e) Milling a sculptured
surface with an end mill,
using a five-axis numerical
control machine.
Conventional vs. Climb Milling
Conventional vs. Climb Milling
Conventional:
Use on manual mills
Tooth engagement is not a
function of workpiece surface
characteristics
Contamination or scale (oxide
layer) on surface does not
adversely affect tool life
Climb:
Preferred on CNC machines
Holds workpiece in place
Improved surface finish
Less re-cutting of chips
Less power Required
Example
A end-milling operation is being carried out on a 300
mm-long, 100 mm-wide annealed mild steel block with
a feed f = 0.13 mm/tooth and a depth of cut of 3 mm.
The cutter is D = 0.5 in. in diameter, has 3 flutes
(teeth), rotates at N = 3000 rpm. Calculate the
material-removal rate.
Face-Milling Cutter (Shell Mill) with
Indexable Inserts
Effect of Insert Shape on Feed Marks on a
Face-Milled Surface
Types of Cutters
Knee Type Milling Machines (Horizontal
and Vertical)
CNC Milling Machines
5-axis Mill
Horizontal CNC Milling with Pallets
http://youtu.be/xZOiNdkJ8SU?t=1m50shttps://www.youtube.com/watch?v=TdxgqpMfIjABroaching
Broaching is a machining operation in which the tool
travels not the workpiece. It uses a long multiple-
tooth cutter to progressively remove more and more
material from the workpiece.
http://youtu.be/e26kCaPjX8E?t=1m19sHobbing
Gear cutting worm with cutting teeth that rotates in
sync with the rotating workpiece
https://www.youtube.com/watch?v=ZpJOEj-kX_o