Introduction about Milling operations

1. Milling operations-types of milling cutter. Gear
cutting – forming and generation principle and
construction of gear milling, hobbing and gear shaping
processes –finishing of gears.

2. MILLING
 Milling is the process of removing metal by feeding the work past against
a rotating multipoint cutter. The metal is removed in the form of small
chips.

3. SPECIFICATION OF MILLING
MACHINE
 The table length and width
 Maximum longitudinal cross and vertical travel of the table
 Number of spindle speeds and feeds
 Power of driving motor
 Floor space required
 Type of milling machine

4. CLASSIFICATION OF MILLING
MACHINE
 Column and knee types
 Plain milling machine
 vertical milling machine
 Universal milling machine
 Ram type milling machine
 omniversal milling machine
 Bed type milling machine
 Simplex milling machine
 Duplex milling machine
 Triplex milling machine
 Plano-type milling machine
 Special purpose milling machine
 Rotary table milling machine
 Drum milling machine
 Profile milling machine

14. WORK HOLDING DEVICES
 The following work holding devices are used for clamping the work in
the milling machine.
 Swivel vice
 Universal vice
 Indexing head

18. TOOL HOLDING DEVICES
 The following tool holding devices are used in milling machines.
Arbors
Adaptors
Collets

22. MILLING CUTTERS
Classification of cutters
According to the shape of the tooth
Milled tooth cutters
Form relieved cutters

23. According to the type of operation
Plain milling cutter
Side milling cutters
End milling cutters
Angle milling cutters
T slot milling cutter
Slitting saws
Form milling cutter
Fly cutters

34. MILLING OPERATIONS
 Plain or slab milling
 Face milling
 Angular milling
 Straddle milling
 Gang milling
 Form milling
 End milling
 T slot milling
 Gear cutting

44. DIVIDING HEADS
These are the following types of dividing heads
Plain or simple dividing head
Universal dividing head
Optical dividing head

48. INDEXING METHODS
 Direct or rapid indexing
 Plain or simple indexing
 Differential indexing
 Compound indexing
 Angular indexing

49. GEAR CUTTING
 Gear cutting by single point form tool
 Gear cutting by shear speed shaping process
 Gear milling using a formed end mill
 Gear broaching
 Template method

50. Gear cutting by single point form tool

51. Gear cutting by shear speed shaping process

52. Gear milling using a formed end mill

53. Gear broaching

54. Template method

55. GEAR GENERATION PRINCIPLE AND
CONSTRUCTION OF GEAR MILLING
 The common gear generation processes are given below
 Gear shaping process
 Gear planning process
 Gear hobbing process

56. GEAR SHAPING PROCESS

58. APPLICATIONS
 Gear shaping is used for generating both internal and external spur
gears.
 Helical gears can also be generated using special attachments.

59. GEAR PLANNING PROCESS

60. GEAR HOBBING PROCESS

62. FINISHING OF GEARS
 Generally the gear teeth are produced by any one of the generating
processes, but the gear does not be more accurate with good quality
surface.
 The rough surface gear teeth occur due to vibrations causing noise,
excessive wear, play and backlash between meshing pair of gears.
 Therefore, the gear finishing is carried at last in gear manufacturing.

63. GEAR SHAVING

64. ROLL FINISHING OF GEAR TOOTH

65. GEAR BURNISHING

66. GEAR LAPPING

67. GEAR HONING