This presentation is about how gears are manufactured. A brief description about methods of gear manufacturing. Scaling the methods from primitive ways of gear manufacturing to specialised meyhods like gear hobbing,rolling,by rack type shaper cutter and finally on milling machine.

1. GEAR
MANUFACTURING
METHODS
NAME-ADITYA KUMAR(IV SEM M.E)
ENROLL NO-40525511117
SUBJECT-MANUFACTURING MACHINES
FACULTY- MR.C S SINGH

2. METHODS OF GEAR
MANUFACTURING
CASTING
ROLLING
POWDER METALLURGY
MACHINING

3. CASTING
 Cast iron fgears are cast in sand moulds or permanent
moulds.
 These gears are rough,weak and inaccurate.
 This method is therefore used for large gears only.
 Small cast gears for light duty work are better produced
by die casting.
 These gears have sufficient accuracy and high surface
finish.

4. GF

6. ROLLING
 Hot rolling process is also used for making gears.
 In this the hot gear blank is rolled against master gears to
produce the desired teeth profile on its periphery.
 The force between the master gear and the blankmakes
the metal flowand obtain the shape and size of the teeth
of the master gear.
 The gears produced through this process possess a highly
finished and smooth surface on their teeth.

8. POWDER METALLURGY
 Small but highly accurate and finished,gears upto 25mm diameters in
general can be easily produced through metallurgy process.
 Such gears are normally used in precission instruments and appliances.
 Gears made through this process are quite dense and strongand
normally do not or require very little further machining

10. GEAR FORMING ON MILLING MACHINE
 Forming process involves finish machining of gear
teeth to a predefined profile by means of form cutters
or single point reciprocating form tools.
 The cutter is mounted on the arbour with its axis at
right angles to the work.
 The indexing movements are determined and the
Sector arms and crank pin adjusted accordingly.
 In a single pass one tooth is finished and the table
Returned to the starting position.

11. GEAR SHAPER PROCESS
 The cutter is mounted with its axis vertical and is
reciprocated up and down by sliding the spindle head
along the vertical ways on the machine.
 In addition to the reciprocating motion,the cutter and
the gear blank both are rotated slowly about their
own axes.
 The cutter in its rotation generates the tooth profile
on the gear blank.
 This method is widely preferred because it enables
higher output and can be used for cutting most of the
different types of gears except worms and worm
wheels.
 This method can also be used for cutting internal
gears.

12. RACK TYPE SHAPER CUTTER
 Another method of gear shaper cutting involves the use
of a rack shaped cutter,called rack type cutter.
 It involves the rotation of gear blank as the rack type
cutter reciprocates in a vertical direction.
 Main problem with this method is that once the full
length of the rack is utilised the cutting operation has to
be stopped in order to bring the gear blank back to its
starting position.

14. GEAR HOBBING
 In this process gear blank is rotated with a rotating
cutter called hob.
 A gear hob looks like a worm,but carries a number of
straight flutes(gashes),cut all around parallel to its axis.
 This results in the production of seperate cutting teeth
cutting edges.
 In operation the hob is rotated at a suitable speed and fed
into the gear blank.
 The blank also rotates simultaneously.