Milling operations

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

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

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

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

8. 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

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

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

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

12. 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

13. Gear cutting by single point form tool

14. Gear cutting by shear speed shaping process

15. Gear milling using a formed end mill

16. Gear broaching

17. Template method

18. 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

19. GEAR SHAPING PROCESS

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

21. GEAR PLANNING PROCESS

22. GEAR HOBBING PROCESS

23. 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.

24. GEAR SHAVING

25. ROLL FINISHING OF GEAR TOOTH

26. GEAR BURNISHING

27. GEAR LAPPING

28. GEAR HONING