prepared by associate prof. mohamed ahmed awad cairo, · pdf fileknurling grooving ......

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


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


Machining Processes

Traditional cutting includes four majortypes of operations:



Shaping moves a single cutting toolsalong flat surface

Traditional cutting includes four majortypes of operations:



Shaping moves a single cutting toolsalong flat surface

4


5


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


6

1. Cutting variables1. Cutting variables

Cutting Variables in turning

8


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


9

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


10

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


11

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


12

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


13

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 )


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....


15

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


16

2. Cutting Tool2. Cutting Tool

Single Point cutting tool


18

Cutting Angles


19

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


21

The Lathe

Bed

HeadStock Tail Stock

Bed

CarriageFeed/LeadScrewPrepared by Dr. Mohamed Ahmed Awad

Chuck

23


Carriage and compound rest

24


2. Work Holding Devices2. Work Holding Devices

WP fixation

26


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

....


27

Three Jaw chuck


28

Three Jaw Chuck


29

Four Jaw chuck


30

Four Jaw chuck


31

Four Jaw chuck independent


32

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

....


34

Fixation using face plate


Non cylindrical


36

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

....


37

Fixation of long WP


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


39

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


40

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


41

Fixation of hollow WP


42

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


43

OperationsOperations


Types of motions in turning


45

Types of motions in turning

46


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

....


47

TurningO

pera

tions

on

Lath

eO

pera

tions

on

Lath

e....

Cylindrical jobO

pera

tions

on

Lath

eO

pera

tions

on

Lath

e....


48

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

....


49

Longitudinal Turning

50


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....


51

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

....


52

Facing

53


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

....


54

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....


55

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

....


56

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


57

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

....


58

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....


59

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


60

Grooving

61


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

....


62

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

63

Recessing

64


Parting Off

65


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


66

Chamfering

67


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

....


68

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

....


69

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

....


70

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


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

72

Facing

73


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


74

Drilling

75


Boring

76


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


77

Contour Turning

78


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

....


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

....


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.


81

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


82

ExampleCan a machine has speed of

191 rpm?Machining time:

minNf

Lt j

t = 500 / (0.7191) = 3.74 minutes


83

prepared by associate prof. mohamed ahmed awad cairo, · pdf fileknurling grooving ......

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