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Prepared byAssociate Prof. Mohamed Ahmed Awad
Cairo, 2014
Machining Process classification
Turning rotates a cylindrical workpiece,while a single-point tool cuts along itslength .
Drilling rotates a multi-point tool andguides it into the workpiece to create ahole .
2
Prepared by Dr. Mohamed Ahmed Awad
Drilling rotates a multi-point tool andguides it into the workpiece to create ahole .
Shaping moves a single cutting tools alongflat surface
Milling rotates a multi-point tool and guidesit along a workpiece to create flat.
ProcessProcessSpeedToolWPProcess
TurningRotary
DrillingRotary
Shapinglinear Shapinglinear
MillingRotary
GrindingRotary
Prepared by Dr. Mohamed Ahmed Awad
Machining Processes
Traditional cutting includes four majortypes of operations:
Turning rotates a cylindrical workpiece,while a single-point tool cuts along itslength .
Drilling rotates a multi-point tool andguides it into the workpiece to create ahole .
Shaping moves a single cutting toolsalong flat surface
Traditional cutting includes four majortypes of operations:
Turning rotates a cylindrical workpiece,while a single-point tool cuts along itslength .
Drilling rotates a multi-point tool andguides it into the workpiece to create ahole .
Shaping moves a single cutting toolsalong flat surface
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Prepared by Dr. Mohamed Ahmed Awad
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Prepared by Dr. Mohamed Ahmed Awad
Machining Process Outline
Cutting variables Cutting tool Machine parts WP fixation Tool fixation Operations Process capability
Cutting variables Cutting tool Machine parts WP fixation Tool fixation Operations Process capability
Prepared by Dr. Mohamed Ahmed Awad
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1. Cutting variables1. Cutting variables
Cutting Variables in turning
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Prepared by Dr. Mohamed Ahmed Awad
Operating/Cutting Conditions
1. Cutting Speed v2. Feed f3. Depth of Cut d
1. Cutting Speed v2. Feed f3. Depth of Cut d
Workpiece
Tool
Chip
Tool post
Speripheralspeed (m/min)
N (rev/min)
D
Prepared by Dr. Mohamed Ahmed Awad
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Operating Conditions
Workpiece
Tool
Chip
Tool post
Speripheralspeed(m/min)
N (rev/min)
D
Workpiece
Tool
Chip
Tool post
Speripheralspeed(m/min)
N (rev/min)
D
NDSspeedperipheral
D
rotation1intraveltoolrelative
Prepared by Dr. Mohamed Ahmed Awad
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Cutting SpeedO
pera
ting
Con
ditio
nsO
pera
ting
Con
ditio
ns....
m/min1000
NDv
D – Diameter (mm)N – Revolutions per Minute (rpm)
The Peripheral Speed of Workpiece past theCutting Tool
=Cutting SpeedOpe
ratin
g C
ondi
tions
Ope
ratin
g C
ondi
tions
....
m/min1000
NDv
Prepared by Dr. Mohamed Ahmed Awad
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Feedf – the distance the tool advances for every
rotation of workpiece (mm/rev)
Ope
ratin
g C
ondi
tions
Ope
ratin
g C
ondi
tions
....
fFeed
DD 21
Ope
ratin
g C
ondi
tions
Ope
ratin
g C
ondi
tions
....
fFeed
DD 21
Prepared by Dr. Mohamed Ahmed Awad
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Depth of Cutperpendicular distance between machined
surface and uncut surface of theWorkpiece
d = (D1 – D2)/2 (mm)
Ope
ratin
g C
ondi
tions
Ope
ratin
g C
ondi
tions
....O
pera
ting
Con
ditio
nsO
pera
ting
Con
ditio
ns....
d Depthof Cut
DD 21
Prepared by Dr. Mohamed Ahmed Awad
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3 Operating Conditions
Chip
Machinedsurface
Workpiece
Depth of cutTool
Chuck
N
Feed (f )
Cutting speed
Depth of cut (d )
Chip
Machinedsurface
Workpiece
Depth of cutTool
Chuck
N
Feed (f )
Cutting speed
Depth of cut (d )
Prepared by Dr. Mohamed Ahmed Awad
14
Material Removal Rate
MRRMRRVolume of material removed in one
revolution MRR = D d f mm3
• Job makes N revolutions/minMRR = D d f N (mm3/min)
In terms of v MRR is given byMRR = 1000 v d f (mm3/min)O
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
MRRMRRVolume of material removed in one
revolution MRR = D d f mm3
• Job makes N revolutions/minMRR = D d f N (mm3/min)
In terms of v MRR is given byMRR = 1000 v d f (mm3/min)O
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
Prepared by Dr. Mohamed Ahmed Awad
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MRR
dimensional consistency bysubstituting the units
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
MRR: D d f N (mm)(mm)(mm/rev)(rev/min)= mm3/min
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
MRR: D d f N (mm)(mm)(mm/rev)(rev/min)= mm3/min
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2. Cutting Tool2. Cutting Tool
Single Point cutting tool
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Cutting Angles
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3. Machine3. Machine
The LatheH ead stock
S p ind le
F eed rod
B ed
C om pound restand slide(sw ivels)
C arriage
A pron
se lec to r
F eed changegearbox
S p ind lespeed
L ead screw
C ross s lideD ead cen ter
T oo l postG u ide w ays
T ails tock qu illT ails tock
H and le
H ead stock
S p ind le
F eed rod
B ed
C om pound restand slide(sw ivels)
C arriage
A pron
se lec to r
F eed changegearbox
S p ind lespeed
L ead screw
C ross s lideD ead cen ter
T oo l postG u ide w ays
T ails tock qu illT ails tock
H and le
Prepared by Dr. Mohamed Ahmed Awad
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The Lathe
Bed
HeadStock Tail Stock
Bed
CarriageFeed/LeadScrewPrepared by Dr. Mohamed Ahmed Awad
Chuck
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Prepared by Dr. Mohamed Ahmed Awad
Carriage and compound rest
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Prepared by Dr. Mohamed Ahmed Awad
2. Work Holding Devices2. Work Holding Devices
WP fixation
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Prepared by Dr. Mohamed Ahmed Awad
Chucks
Three jaw Four JawW
orkh
oldi
ngW
orkh
oldi
ngDe
vice
sDe
vice
s....
Wor
khol
ding
Wor
khol
ding
Devi
ces
Devi
ces
....
Prepared by Dr. Mohamed Ahmed Awad
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Three Jaw chuck
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Three Jaw Chuck
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Four Jaw chuck
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Four Jaw chuck
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Four Jaw chuck independent
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4/24/2017Lab6: Roundness Test33Prepared by Dr. Mohamed Ahmed Awad
Faceplates
Wor
kpie
ce
Wor
khol
ding
Dev
ices
Wor
khol
ding
Dev
ices
....
Wor
kpie
ce
Wor
khol
ding
Dev
ices
Wor
khol
ding
Dev
ices
....
Prepared by Dr. Mohamed Ahmed Awad
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Fixation using face plate
Prepared by Dr. Mohamed Ahmed Awad
Non cylindrical
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Centers
Workpiece
Headstock center(Live Centre)
Tailstock center(Dead Centre)
Wor
khol
ding
Dev
ices
Wor
khol
ding
Dev
ices
....
Workpiece
Headstock center(Live Centre)
Tailstock center(Dead Centre)
Wor
khol
ding
Dev
ices
Wor
khol
ding
Dev
ices
....
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Fixation of long WP
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38
DogsW
orkh
oldi
ng D
evic
esW
orkh
oldi
ng D
evic
es....
Tail
Tail
Wor
khol
ding
Dev
ices
Wor
khol
ding
Dev
ices
....
Tail
Tail
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RestsW
orkh
oldi
ng D
evic
esW
orkh
oldi
ng D
evic
es....
Jaws
HingeWork Work Jaws
Lathe bed guideways
Carriage
Steady Rest Follower RestW
orkh
oldi
ng D
evic
esW
orkh
oldi
ng D
evic
es....
Jaws
HingeWork Work Jaws
Lathe bed guideways
Carriage
Prepared by Dr. Mohamed Ahmed Awad
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RestsW
orkh
oldi
ng D
evic
esW
orkh
oldi
ng D
evic
es....
Jaws
HingeWork Work Jaws
Lathe bed guideways
Carriage
Steady Rest Follower RestW
orkh
oldi
ng D
evic
esW
orkh
oldi
ng D
evic
es....
Jaws
HingeWork Work Jaws
Lathe bed guideways
Carriage
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Fixation of hollow WP
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MandrelsWorkpiece (job) with a hole
Wor
khol
ding
Dev
ices
Wor
khol
ding
Dev
ices
....
Workpiece Mandrel
Wor
khol
ding
Dev
ices
Wor
khol
ding
Dev
ices
....
Workpiece Mandrel
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OperationsOperations
Prepared by Dr. Mohamed Ahmed Awad
Types of motions in turning
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Types of motions in turning
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Prepared by Dr. Mohamed Ahmed Awad
Operations on Lathe
TurningFacingknurlingGroovingParting
ChamferingTaper turningDrillingThreading
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
TurningFacingknurlingGroovingParting
ChamferingTaper turningDrillingThreading
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
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TurningO
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
Cylindrical jobO
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
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Turning ..
Cylindrical job
Cuttingspeed
Chip
Workpiece
Depth of cut (d)
Depth of cutTool
FeedChuck
NMachinedsurface
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Cuttingspeed
Chip
Workpiece
Depth of cut (d)
Depth of cutTool
FeedChuck
NMachinedsurface
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Prepared by Dr. Mohamed Ahmed Awad
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Longitudinal Turning
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Prepared by Dr. Mohamed Ahmed Awad
Turning .. Excess Material is
removed to reduceDiameterCutting Tool: Turning Tool
a depth of cut of 1 mmwill reduce diameter by 2mmO
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
Excess Material isremoved to reduceDiameterCutting Tool: Turning Tool
a depth of cut of 1 mmwill reduce diameter by 2mmO
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
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FacingFlat Surface/Reduce length
Depth ofcut
Feed
WorkpieceChuck
Cuttingspeed
Tool
dMachinedFace
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Depth ofcut
Feed
WorkpieceChuck
Cuttingspeed
Tool
dMachinedFace
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Prepared by Dr. Mohamed Ahmed Awad
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Facing
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Prepared by Dr. Mohamed Ahmed Awad
Facing ..
machine end of job Flat surfaceor to Reduce Length of Job
Turning ToolFeed: in direction perpendicular to
workpiece axisLength of Tool Travel = radius of
workpieceDepth of Cut: in direction parallel to
workpiece axisOpe
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....machine end of job Flat surface
or to Reduce Length of JobTurning ToolFeed: in direction perpendicular to
workpiece axisLength of Tool Travel = radius of
workpieceDepth of Cut: in direction parallel to
workpiece axisOpe
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
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Eccentric Turning
Axis of job
Axis of lathe
Eccentric peg(to be turned)
4-jawchuck
CuttingspeedO
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
Axis of job
Axis of lathe
Eccentric peg(to be turned)
4-jawchuck
CuttingspeedO
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
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Knurling Produce rough textured surface For Decorative and/or Functional Purpose
Knurling Tool
A Forming Process MRR~0
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
.... Produce rough textured surface For Decorative and/or Functional Purpose
Knurling Tool
A Forming Process MRR~0
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
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KnurlingO
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
Knurling toolTool post
Feed
Cuttingspeed
Movementfor depth
Knurled surface
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Knurling toolTool post
Feed
Cuttingspeed
Movementfor depth
Knurled surface
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Knurling ..O
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
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GroovingProduces a Groove on
workpieceShape of tool shape of
grooveCarried out using Grooving
Tool A form toolAlso called Form TurningO
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
Produces a Groove onworkpieceShape of tool shape of
grooveCarried out using Grooving
Tool A form toolAlso called Form TurningO
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
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Grooving ..O
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
Shape producedby form tool Groove
Groovingtool
Feed ordepth of cutForm tool
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....Shape producedby form tool Groove
Groovingtool
Feed ordepth of cutForm tool
Prepared by Dr. Mohamed Ahmed Awad
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Grooving
61
Prepared by Dr. Mohamed Ahmed Awad
Parting Cutting workpiece into Two Similar to grooving Parting Tool Hogging – tool rides over – at slow feed Coolant use
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
.... Cutting workpiece into Two Similar to grooving Parting Tool Hogging – tool rides over – at slow feed Coolant use
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
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Parting ..O
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
FeedParting toolOpe
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
FeedParting toolPrepared by Dr. Mohamed Ahmed Awad
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Recessing
64
Prepared by Dr. Mohamed Ahmed Awad
Parting Off
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Prepared by Dr. Mohamed Ahmed Awad
ChamferingO
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
Chamfering toolFeed
ChamferO
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
Chamfering toolFeed
Chamfer
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66
Chamfering
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Prepared by Dr. Mohamed Ahmed Awad
Chamfering
Beveling sharp machined edges Similar to form turning Chamfering tool – 45° To
• Avoid Sharp Edges• Make Assembly Easier• Improve Aesthetics
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
.... Beveling sharp machined edges Similar to form turning Chamfering tool – 45° To
• Avoid Sharp Edges• Make Assembly Easier• Improve Aesthetics
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Prepared by Dr. Mohamed Ahmed Awad
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Taper Turning
Taper:
CB
A L
D90°
2D1
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
L
DD
2tan 21
CB
A L
D90°
2D1
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Prepared by Dr. Mohamed Ahmed Awad
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Taper Turning..
MethodsMethods Form Tool Swiveling Compound Rest Taper Turning Attachment Simultaneous Longitudinal and
Cross FeedsOpe
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....Conicity
L
DDK 21
MethodsMethods Form Tool Swiveling Compound Rest Taper Turning Attachment Simultaneous Longitudinal and
Cross FeedsOpe
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
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Taper Turning ..By Form Tool
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
TaperWorkpiece
Straightcutting edge
Directionof feed
FormtoolO
pera
tions
on
Lath
eO
pera
tions
on
Lath
e....
TaperWorkpiece
Straightcutting edge
Directionof feed
Formtool
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71
Taper Turning ,,By Compound Rest
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Face plate
Dog
Tail stock quill
Tail stock
Mandrel
Direction of feed
Compound restSlide
Compound restHand crank
Tool post &Tool holder
Cross slideOpe
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Face plate
Dog
Tail stock quill
Tail stock
Mandrel
Direction of feed
Compound restSlide
Compound restHand crank
Tool post &Tool holder
Cross slidePrepared by Dr. Mohamed Ahmed Awad
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Facing
73
Prepared by Dr. Mohamed Ahmed Awad
DrillingDrill – cutting tool – held in TS – feed from
TS
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Feed
Drill
Quillclamp moving
quill
Tail stock clamp
Tail stock
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Feed
Drill
Quillclamp moving
quill
Tail stock clamp
Tail stock
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Drilling
75
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Boring
76
Prepared by Dr. Mohamed Ahmed Awad
Process Sequence How to make job from raw material 45 long
x 30 dia.?
20 dia
40
15
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Steps:•Operations•Sequence•Tools•Process
20 dia
40
15
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Steps:•Operations•Sequence•Tools•Process
Prepared by Dr. Mohamed Ahmed Awad
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Contour Turning
78
Prepared by Dr. Mohamed Ahmed Awad
Machining Time
Turning Time Job length Lj mm Feed f mm/rev Job speed N rpm f N mm/min
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....Turning Time Job length Lj mm Feed f mm/rev Job speed N rpm f N mm/min
minNf
Lt j
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
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79
Manufacturing Time
Manufacturing Time= Machining Time+ Setup Time+ Moving Time+ Waiting Time
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
Manufacturing Time= Machining Time+ Setup Time+ Moving Time+ Waiting Time
Ope
ratio
ns o
n La
the
Ope
ratio
ns o
n La
the
....
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80
ExampleA mild steel rod having 50 mm diameter and
500 mm length is to be turned on a lathe.Determine the machining time to reducethe rod to 45 mm in one pass when cuttingspeed is 30 m/min and a feed of 0.7mm/rev is used.
A mild steel rod having 50 mm diameter and500 mm length is to be turned on a lathe.Determine the machining time to reducethe rod to 45 mm in one pass when cuttingspeed is 30 m/min and a feed of 0.7mm/rev is used.
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Example
m/min1000
NDv
Given data: D = 50 mm, Lj = 500 mmv = 30 m/min, f = 0.7 mm/rev
Substituting the values of v and D in
calculate the required spindle speed as: N =191 rpm
m/min1000
NDv
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82
ExampleCan a machine has speed of
191 rpm?Machining time:
minNf
Lt j
t = 500 / (0.7191) = 3.74 minutes
Prepared by Dr. Mohamed Ahmed Awad
83
Recommended