Broaching is a machining process that uses a toothed tool called a broach to remove material in a single pass. Broaching was first used in the 1850s and was commonly used to rifle gun barrels during World War 1. Broaching machines can perform horizontal, vertical, continuous, and rotary broaching. Broaching tools are designed based on the material, size and shape of the cut, required tolerances, and production rates. Broaching provides high production rates and accuracy for complex hole shapes and surfaces.

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By :
VIRENDRA RATHORE
Manufacturing Engg.
Roll no. 163517

2. BROACHING
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Broaching is a maching process that uses a toothed
tool,called a broach ,to remove material.
Broaching is a similar technique to shaping with a long
multiple-tooth cutter.

3. Traced back to the early 1850.
During world war 1,broaching was used to rifle gun
barrels.
Requirements of close tolerances and reduced cost
need broaching.
HISTORY AND REQUIREMENT
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5. These machines are designed for pull broaching, surface
broaching, continuous broaching, and rotary broaching
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HORIZONTAL BROACHING

6. These machines can be designed for push broaching, pull-
down broaching, pull-up broaching, or surface broaching.
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VERTICAL BROACHING

7. CONTINUOUS BROACHING
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8. ROTARY BROACHING
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Where
Θ=off- axis angle,
Θr =rake,
Θf = front releif, W=width across corners, dp =
pilot
diameter

9. BROACHING TOOL
WHERE
P=pitch, γ=clearance angle, α=rake angle.
RPT=rise per tooth,L=land.
R=radius of the gullet.
D=depth of the tooth.
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Broaching tool geometry

10. Broaching Tools
Design and construction considerations
– Material to be broached
– Size and shape of cut
– Quality of surface finish
– Part tolerance
– Productions rates
– Type of machine
–Workholding method
– Strength of the workpiece
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11. DESIGN
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BASIC PRINCIPLE OF BROACHING

13. WORKING
Uses a single pass for finished shapes or sized.
Uses a multipoint cutting tool (broach) .
The rise per tooth determines the amount of
material removed and the size of chips.
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14. Chip breaker Features on Broaches
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Figure 24.22 Chipbreaker features on (a) a flat broach and (b) a round broach.

15. MATERIAL OF BROACH
 Based on cutting tool material properties.
Mostly made up of HSS. Ceramic are not used as low
speed.
Cemented carbide segments or replaceable inserts are
also used specially for CI and steels. TiN coating
provide high life.
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16. PRODUCTS OF BROACHING
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17. Broaching products
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Complex hole shapes cut by broaching

18. CUTTING FORCE VARIATIONS
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FMAX[kg]=a[mm2
]*re[KG/MM
2]*
n
Where
a=areaofmaterialrequired.
re=specificresistanceofcutting.
n=numberofcuttingteethsimultaneously.
n=l/p
Where

19. Mechanics of metal cutting in
broaching
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20. •The cutting force in broaching can be expressed generally by
three differential components which are directly related to the chip
load area and the contact length between the cutting edge and the
workpiece such as,
dft = Ktc × hi × dli + Kte × dli,
dff= Kfc × hi × dli + Kfe× dli,
dfr = Krc × hi × dli + Kre × dli.
dft =differential component of tangential force,
dff =differential component of feed force,
dfr =differential component of radial force.
dhi and dli are chip thickness and length of the cut for infinitesimal element along the cutting edge
respectively.
kc and ke are cutting and edge constants.
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Force model for orthogonal broaching using B-spline
interpolation of cutting edge.

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22. B SPLINE INTERPOLATION OF
CUTTING EDGE
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Data points D and control points P can be organized in a
system of equations consisting of (n + 1) × (n + 1) matrix
as shown:

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Fig. 4. B-spline interpolation of cutting edge.

25. Calculation of Chip Load and Contact Length for
Orthogonal and Oblique Broaching
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Orthogonal broaching

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Oblique broaching
Contd..

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Contd...
where s, e, i, i − 1 indicate start of the cut, end of the cut,
current cutting edge,and previous cutting edge respectively

28. RESULTS (ORTHOGONAL)
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29. OBLIQUE CUTTING FORCES(contd..)
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30. CAPABILITY CHART
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31. Very high production rate (much higher than milling,
planing, boring etc.)
High dimensional and form accuracy and surface finish of
the product .
 Roughing and finishing in single stroke of the same
cutter .
 Needs only one motion (cutting), so, operation and
control are simpler.
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WHY TO PREFER IT

32. • Design, manufacture and restoration of the broaches are
difficult and expensive.
• Defects or damages in the broach (cutting edges) severely
affect product quality.
• Only through holes and surfaces can be machined.
• Economic only when the production volume is large.
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WHY TO AVOID IT

33. BROACHING PROCESS ARE VERSATILE.WITH THE HIGH SCOPE
IN FUTURE.
THERE ARE CERTAIN THINGS TO BE RESOLVE OUT BUT IN THE
FUTURE IT WILL CONTRIBUTE MUCH IN MACHINING.
FORCE VIBRATION ARE TO BE RESOLVE OUT AND TOOL COST.
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34.  "Linear Broaching Made Simple With Benz LinA/LinS". www.cutwel.co.uk.
Cutwel.
 "Rotary Broaching on a Bridgeport" (Video). Polygon Solutions Inc. 15 December
2010. Retrieved 24 May 2011.
 http://en.wikipedia.org/wiki/Broaching.
 High speed broaching of hard machining materials.V.F. Makarov, D. I.
Tokarev, V.R. Tyktamishev.
 Prediction of cutting forces in broaching operation,Article in Journal of
Advanced Manufacturing Systems · August 2013
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