METMETMETMETMETAL CUTTINGAL CUTTINGAL CUTTINGAL CUTTINGAL CUTTING

AND TOOL DESIGNAND TOOL DESIGNAND TOOL DESIGNAND TOOL DESIGNAND TOOL DESIGN

An ISO 9001:2008 Certified Company

Vayu Education of India2/25, Ansari Road, Darya Ganj, New Delhi-110 002

ASHOK KUMAR SINGH

Assistant ProfessorAssistant ProfessorAssistant ProfessorAssistant ProfessorAssistant Professor

Mechanical Engineering Department

Galgotia College of Engineering and Technology

Greater Noida (U.P.)

Metal Cutting and Tool Design

Copyright ©VAYU EDUCATION OF INDIA

ISBN: 978-93-83758-21-0

First Edition: 2014

Price: 180/-

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Contents

1.1.1.1.1. Metal MachiningMetal MachiningMetal MachiningMetal MachiningMetal Machining ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ 11111

1.1 Introduction ................................................................................................. 1

1.2 Fundamentals ............................................................................................. 1

Exercises ...................................................................................................... 13

2.2.2.2.2. Mechanics of Metal CuttingMechanics of Metal CuttingMechanics of Metal CuttingMechanics of Metal CuttingMechanics of Metal Cutting ....................................................................................................................................................................................................................................................................................................................................................................................... 1414141414

2.1 Mechanics .................................................................................................. 14

2.2 Chip Formation ......................................................................................... 14

2.2.1 Continuous Chips ......................................................................... 15

2.2.2 Continuous Chips with Built-up-Edge ...................................... 16

2.2.3 Discontinuous Chips .................................................................... 17

2.3 Orthogonal Cutting .................................................................................. 18

2.3.1 Thin Zone Models in Orthogonal Cutting ................................. 19

2.3.2 Determination of Shear Plane Angle .......................................... 19

2.3.3 Cutting Forces in Orthogonal Cutting ........................................ 20

2.3.4 Merchant’s Model For Orthogonal Cutting ............................... 21

2.3.5 Ploughing Force ............................................................................ 22

2.3.6 Chip Velocity ................................................................................. 24

2.3.7 Cutting with Variable Uncut Chip Thickness ........................... 25

Exercises ...................................................................................................... 26

3.3.3.3.3. Measurement of Cutting ForcesMeasurement of Cutting ForcesMeasurement of Cutting ForcesMeasurement of Cutting ForcesMeasurement of Cutting Forces ......................................................................................................................................................................................................................................................................................................................................................... 2828282828

3.1 Measurement of Cutting forces ............................................................... 28

3.2 Merchant’s Analysis for Chip Thickness Ratio .................................... 28

3.3 Determination of Cutting Forces ............................................................. 30

3.4 Determination of Area of Shear Plane and Shear Strength .................. 31

3.5 Assumptions of Merchant’s Circle ......................................................... 33

3.6 Determination of Shear angle .................................................................. 34

3.7 Velocity Triangle ....................................................................................... 34

3.8 Ernest and Merchant Theory ................................................................... 35

3.9 Lee and Shaffer (Slip Line Field Theory) ................................................ 36

Exercises ...................................................................................................... 40

4.4.4.4.4. Heat in Metal CuttingHeat in Metal CuttingHeat in Metal CuttingHeat in Metal CuttingHeat in Metal Cutting .............................................................................................................................................................................................................................................................................................................................................................................................................................................. 4242424242

4.1 Introduction ............................................................................................... 42

4.2 Shear Plane Temperature in Orthogonal Cutting ................................. 43

4.3 Measurement of Temperature .................................................................. 46

4.3.1 Tool Work Piece Thermocouple ................................................... 46

4.3.2 Inserted Thermocouple ................................................................. 46

4.3.3 Infrared Measurement ................................................................. 47

4.3.4 Hardness and Microstructure Studies ....................................... 47

4.4 Cutting Fluids ........................................................................................... 47

4.4.1 Properties of Cutting Fluids ......................................................... 47

4.4.2 Selection of Cutting Fluids ........................................................... 48

4.4.3 Work Piece Material ...................................................................... 48

Exercises ...................................................................................................... 48

5.5.5.5.5. FailurFailurFailurFailurFailure of Cutting Te of Cutting Te of Cutting Te of Cutting Te of Cutting Toolsoolsoolsoolsools ............................................................................................................................................................................................................................................................................................................................................................................................................................... 5050505050

5.1 Introduction ............................................................................................... 50

5.2 Tool Wear Mechanisms ............................................................................ 50

5.2.1 Shearing at High Temperature .................................................... 50

5.2.2 Diffusion Wear .............................................................................. 51

5.2.3 Adhesive Wear (Attrition wear) .................................................. 52

5.2.4 Abrasive Wear ............................................................................... 52

5.2.5 Fatigue Wear .................................................................................. 53

5.2.6 Electrochemical Effect ................................................................... 54

5.2.7 Oxidation Effect ............................................................................. 54

5.2.8 Chemical Decomposition ............................................................. 54

5.3 Types of Tool Damage During Cutting ................................................... 54

5.3.1 Flank Wear ..................................................................................... 55

5.3.2 Crater Wear .................................................................................... 56

5.3.3 Chipping (Premature Tool Failure) ............................................. 56

5.4 Wear and Chipping Characteristics Different Tool Materials ............ 57

5.4.1 HSS ................................................................................................. 57

5.4.2 Tungsten Carbide-Cobalt (WC-Co) Tool Material ..................... 57

5.4.3 Tungsten Carbide - Titanium Carbide - Tantalum - Carbide -Cobalt (WC-TiC-TaC-Co) Tool Material ..................................... 58

5.4.4 Alumina (Cemented Oxide) Tools ............................................... 58

5.4.5 Sialon .............................................................................................. 58

5.4.6 Cubic Boron Nitride ...................................................................... 58

5.4.7 Diamond ........................................................................................ 58

5.5 Tool Wear Equations ................................................................................ 58

5.5.1 Abrasive Wear ............................................................................... 59

5.5.2 Adhesive Wear Models Flank Wear ........................................... 59

5.6 Tool Failure Criteria ................................................................................. 59

5.6.1 Direct Criteria ................................................................................ 60

5.6.2 Indirect Criteria ............................................................................. 61

5.7 Tool Life Equations ................................................................................... 62

5.7.1 Taylor ’s Tool Life Equation ........................................................ 62

5.7.2 Comments on Tool Life Equations .............................................. 63

5.8 Effect of Process Parameters on Tool Life ............................................... 66

5.8.1 Tool Material Properties ............................................................... 66

5.8.2 Coating of Tool .............................................................................. 66

5.8.3 Work Material ................................................................................ 66

5.8.4 Speed, Feed and Depth of Cut ..................................................... 67

5.8.5 Tool Geometry ............................................................................... 67

5.8.6 Cutting Fluid ................................................................................. 69

5.8.7 Vibration Behaviour of the Machine-Tool Work System .......... 69

5.8.8 Interruption in the Cut ................................................................. 69

5.8.9 Built-up Edge ................................................................................. 69

Exercises ...................................................................................................... 69

6.6.6.6.6. Tool Wear MeasurementTool Wear MeasurementTool Wear MeasurementTool Wear MeasurementTool Wear Measurement ................................................................................................................................................................................................................................................................................................................................................................................................................ 7171717171

6.1 Introduction ............................................................................................... 71

6.1.1 Flank Wear ..................................................................................... 72

6.1.2 Crater Wear .................................................................................... 72

6.1.3 Chipping (Premature Tool Failure) ............................................. 73

6.2 Tool Wear Equations ................................................................................ 73

6.2.1 Abrasive Wear ............................................................................... 73

6.2.2 Adhesive Wear Models Flank Wear ............................................ 74

6.2.3 Diffusion Wear .............................................................................. 76

6.3 Tool Failure Criteria .................................................................................. 78

6.3.1 Direct Criteria ................................................................................ 78

Exercises ...................................................................................................... 79

7.7.7.7.7. TTTTTool Materialool Materialool Materialool Materialool Material ......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... 8080808080

7.1 Introduction ............................................................................................... 80

7.2 Cutting-Tool Materials ............................................................................. 84

7.2.1 Tool Steels ...................................................................................... 84

7.2.2 High-Speed Steels ......................................................................... 84

7.2.3 TiN-Coated High-Speed Steels .................................................... 85

7.3 Tool Materials in Brief .............................................................................. 85

7.4 Tool Coating Processes ............................................................................ 87

7.4.1 CVD ................................................................................................ 88

7.4.2 PVD ................................................................................................. 88

8.8.8.8.8. Cemented Titanium Carbide ToolCemented Titanium Carbide ToolCemented Titanium Carbide ToolCemented Titanium Carbide ToolCemented Titanium Carbide Tool ..................................................................................................................................................................................................................................................................................................................................... 9494949494

8.1 Carbide or Sintered Carbides .................................................................. 94

8.2 Coated-carbide Tools ................................................................................ 96

9.9.9.9.9. Ceramic Cutting ToolCeramic Cutting ToolCeramic Cutting ToolCeramic Cutting ToolCeramic Cutting Tool ................................................................................................................................................................................................................................................................................................................................................................................................................................................... 9797979797

9.1 Introduction ............................................................................................... 97

9.2 Cermets ...................................................................................................... 97

9.3 Diamonds .................................................................................................. 98

9.4 Polycrystalline Cubic Boron Nitrides ................................................... 100

10.10.10.10.10. Tool GeometryTool GeometryTool GeometryTool GeometryTool Geometry ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ 102102102102102

10.1 Cutting Tool Geometery ......................................................................... 102

10.2 Chip Flow Direction ............................................................................... 103

10.3 Angle Specification Systems.................................................................. 104

10.3.1 British System .............................................................................. 104

10.3.2 American System (ASA System) ................................................ 105

10.3.3 German System (DIN system) .................................................... 105

10.3.4 Normal Rake System (ISO System) ............................................ 106

10.3.5 Conversion of Various Rake Angle Systems into NormalRake System ................................................................................. 107

10.4 Cutting Parameters and Tool Geometry ............................................... 109

10.4.1 Rake Angle ................................................................................... 109

10.4.2 Relief Angles ................................................................................ 109

10.4.3 Cutting Edge Angles ................................................................... 110

10.4.4 Nose Radius ................................................................................ 110

10.5 Indexable Inserts ..................................................................................... 110

10.5.1 Disposable Inserts ....................................................................... 110

Exercises .................................................................................................... 112

11.11.11.11.11. Cutting FluidsCutting FluidsCutting FluidsCutting FluidsCutting Fluids .......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... 113113113113113

11.1 Introduction ............................................................................................. 113

11.2 Benefits of Using Cutting Fluids ........................................................... 115

11.3 Methods of Applying Cutting Fluids ................................................... 116

11.4 Types of Cutting Fluids .......................................................................... 118

11.5 Composition of Cutting Fluids .............................................................. 118

11.6 Selection of Cutting Fluids ..................................................................... 119

Exercises .................................................................................................... 120

12.12.12.12.12. Economics of MachiningEconomics of MachiningEconomics of MachiningEconomics of MachiningEconomics of Machining ........................................................................................................................................................................................................................................................................................................................................................................................................... 121121121121121

12.1 Introduction ............................................................................................. 121

12.2 Costs for Single Pass Turning Operations ........................................... 122

12.3 Optimum Cutting Speed for Minimum Cost in Turning .................... 124

12.4 Optimum Cutting Speed for Maximum Rate of Productionin Turning ................................................................................................ 125

12.5 Optimum Cutting Speed for Maximum Profit / Rate in Turning ..... 126

12.6 EEffect of Feed on Cutting Speed for Minimum Cost in Turning ...... 128

12.7 Restrictions on Optimum Cutting Conditions .................................... 130

Exercises .................................................................................................... 131

13.13.13.13.13. Cutting Tool DesignCutting Tool DesignCutting Tool DesignCutting Tool DesignCutting Tool Design ................................................................................................................................................................................................................................................................................................................................................................................................................................................... 132132132132132

13.1 Introduction ............................................................................................. 132

13.2 Terminology of Single Point Cutting Tool (As Per ASA) .................... 133

13.2.1 Back rake angle ........................................................................... 133

13.2.2 Side cutting edge angle (Y) ......................................................... 134

13.3.3 Side Rake Angle .......................................................................... 136

13.3.4 Side Relief Angle ......................................................................... 136

13.3.5 End Cutting Edge Angle ............................................................ 136

13.3.6 End Relief Angle (Clerance angle) ............................................ 137

13.3.7 Nose Radius ................................................................................ 137

13.3.8 ASA Tool Signature ..................................................................... 137

13.4 British System.......................................................................................... 137

13.5 Normal or Orthogonal Rake System (ORS) .......................................... 137

14.14.14.14.14. Design of Single Point TDesign of Single Point TDesign of Single Point TDesign of Single Point TDesign of Single Point Tooloolooloolool .................................................................................................................................................................................................................................................................................................................................................................................. 139139139139139

14.1 Tool Geometry ......................................................................................... 139

14.2 Chip Flow Direction ............................................................................... 142

14.3 Tool Angle Specification Systems ........................................................ 143

14.3.1 British System .............................................................................. 143

14.3.2 American System (ASA System) ................................................ 143

14.3.3 German System (DIN system) .................................................... 144

14.3.4 Normal Rake System (ISO System) ............................................ 144

14.3.5 Conversion of Various Rake Angle Systems into NormalRake System ................................................................................. 145

14.4 Cutting Parameters and Tool Geometry ............................................... 147

14.4.1 Rake Angle ................................................................................... 147

14.4.2 Relief Angles ................................................................................ 147

14.4.3 Cutting Edge Angles ................................................................... 148

14.4.4 Nose Radius ................................................................................ 148

14.5 Indexable Inserts ..................................................................................... 148

14.5.1 Disposable Inserts ....................................................................... 148

14.6 Tools Having Unusual Geometry ......................................................... 152

14.7 Expression for an, av and I .................................................................... 153

Exercises .................................................................................................... 154

15.15.15.15.15. Design of DrillDesign of DrillDesign of DrillDesign of DrillDesign of Drill ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ 155155155155155

15.1 Drilling ..................................................................................................... 155

15.2 Drills ....................................................................................................... 156

16.16.16.16.16. Design of Milling CutterDesign of Milling CutterDesign of Milling CutterDesign of Milling CutterDesign of Milling Cutter ................................................................................................................................................................................................................................................................................................................................................................................................................ 161161161161161

16.1 Milling Cutters ........................................................................................ 161

16.1.1 Plain Milling Cutters or Slab Mills ........................................... 161

16.1.2 Side and Face Milling Cutters ................................................... 162

16.1.3 End Mills ...................................................................................... 163

16.1.4 Face Milling Cutters .................................................................... 165

16.1.5 Slitting Saws ................................................................................ 166

16.1.6 Form Relieved Milling Cutters ................................................... 167

17.17.17.17.17. Design of BroachDesign of BroachDesign of BroachDesign of BroachDesign of Broach ............................................................................................................................................................................................................................................................................................................................................................................................................................................................................ 168168168168168

17.1 Design of Broaches ................................................................................. 168

17.1.1 Pull-Type Broach ........................................................................ 169

17.1.2 Surface Broach Design ............................................................... 171

18.18.18.18.18. Cutting Tool ManufacturingCutting Tool ManufacturingCutting Tool ManufacturingCutting Tool ManufacturingCutting Tool Manufacturing ............................................................................................................................................................................................................................................................................................................................................................................. 174174174174174

18.1 Introduction ............................................................................................. 174

18.2 Drilling and Reaming ............................................................................ 176

18.2.1 Machining Parameters and Related Quantities for Drilling .. 176

18.3 Broaching ................................................................................................ 177

18.3.1 Roughing teeth A Key Way Broach .......................................... 178

18.4 Milling ...................................................................................................... 178

19.19.19.19.19. Gear Cutting ToolsGear Cutting ToolsGear Cutting ToolsGear Cutting ToolsGear Cutting Tools ............................................................................................................................................................................................................................................................................................................................................................................................................................................................. 181181181181181

19.1 Introduction ............................................................................................. 181

19.1.1 Physical Requirements of Gears ................................................ 183

19.2 Gear Types ............................................................................................... 183

19.3 Gear Manufacturing ............................................................................... 185

19.4 Machining of Gears ................................................................................ 187

19.5 Gear Finishing ........................................................................................ 190

20.20.20.20.20. Thread Cutting ToolsThread Cutting ToolsThread Cutting ToolsThread Cutting ToolsThread Cutting Tools ......................................................................................................................................................................................................................................................................................................................................................................................................................................... 194194194194194

20.1 Introduction ............................................................................................. 194

20.2 Reamers ................................................................................................... 195

20.3 Thread Cutting Tools ............................................................................ 197

21.21.21.21.21. Design of ReamerDesign of ReamerDesign of ReamerDesign of ReamerDesign of Reamer .................................................................................................................................................................................................................................................................................................................................................................................................................................................................. 198198198198198

21.1 Reamers ................................................................................................... 198

IndexIndexIndexIndexIndex ................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ 201201201201201

CHAPTER

1

Metal Machining

1.1 INTRODUCTION

Machining is the process of removing unwanted material from a workpiece in the

form of chips. If the workpiece is metal, the process is often called metal cutting or

metal remoml.

• Prior workhardening greatly affects the process.

• Different materials behave differently.

• The process is asymmetrical and unconstrained, bounded only by the cutting

tool.

• The level of strain is very large.

• The strain rate is very high.

• The process is sensitive to variations in tool geometry, tool material, temperature,

environment (cutting fluids), and process dynamics (chatter and vibration).

1.2 FUNDAMENTALS

The process of metal cutting is complex because it has such a wide variety of inputs,

which are listed in Figure 1.1. The variables are:

• The machine tool selected to perform the process

• The cutting tool selected (geometry and material)

• The properties and parameters of the workpiece

• The cutting parameters selected (speed, feed, depth of cut)

• The workpiece holding devices or fixtures or jigs

2 Metal Cutting and Tool Design

• Lathe• Milling machine• Drill press• Grinder• Saw• Broach• Machining centers

Tool design geometry• Tool angles• Nose radius• Edge radius• Material• Hardness• Finish• Coating

Machining processes

1. Oblique-point cutting• Single-point cutting• Multiple-edge tools

Measurements

Cutting forcesChip dimensions• Optical• SemOnset ofshear direction ypowerSurface finishTool wear failuresDeflectionsTemperaturesVibrationsPart size

Turningsingle-pointtool process

Tool

Work

ChipNS

D2V

D1

Workpiece Parameters

Predeformation (workHardening prior tomachining)Metal type• BCC, FCC, HCP• SFEPurity

Cutting parameters

Depth of cutSpeed feedEnvironment• oxyqen• Lubricant• Temperature

WorkholderFixturesJigsChucksCollents

Machine tool selection

fr

Chip

Workpiece

Tool

Determinations

Specific horsepower, HP,Flow stress, T

Chip ratios, r

Shear front directions,Velocities (Chip, shear,and so on)

Sriains,

Strains rates,Cutting stiffness, k

heat in tool

s|

c

s

y

m

g

Friction coefficients

g

The fundamental inputs to machining processes

II. Orthogonal (two-force) madel

• Macroindustrial studies performedon plates and tubes

• Microstudies carried out in microscopesusing high-speed photography

Fig. 1.1 The fundamental inputs and outputs to machining processes.

Work ratates

Tool feedsturning

Saw blade

Work

Sawing

Wheelrotates

Work feeds

Grinding

Cutterrotates

Fork feeds

Milling

Metal Machining 3

Recuperatingtool

Work feedslaterally

Shaping

or

Tool feedslaterally

Workreciprocates

Planing

Cuttingtool movesinto workBroach

WorkstationaryBroaching Work stationary

drilling

Drill feedsand rotates

Fig. 1.2 The seven basic machining processes used in chip formation

For all metal cutting processes, it is necessary to determine the parameters, speed,

feed, and depth of cut. The turning process will be used to introduce these terms. In

general, speed (V) is the primary cutting motion, which relates the velocity of the

cutting tool relative to the workpiece. It is generally given in units of surface feet per

minute (sfpm), inches per minute (in./min), meters per minute (m/m), or meters per

second (m/s). Speed (V) is shown with the heavy dark arrow. Feed (f,) is the amount

of material removed per revolution or per pass of the tool over the workpiece. In

turning, feed is in inches per revolution, and the tool feeds parallel to the rotational axis

of the workpiece. Depending on the process, feed units are inches per revolution,

inches per cycle, inches per minute, or inches per tooth. Feed is shown with dashed

arrows. The depth of cut (DOC) represents the third dimension. In turning, it is the

distance the tool is plunged into the surface. It is half the difference in the initial

diameter, D1, and the final diameter, D

2:

DOC =1 2

2

D Dd

−=

The selection of the cutting speed V determines the surface speed of the rotating

part that is related to the outer diameter of the workpiece.

V =1

12

sD Nπ

where D1 is in inches, V is speed in surface feet per minute and N

s is the revolutions

per minute (rpm) of the workpiece. The input to the lathe will be in revolutions per

minute of the spindle.

4 Metal Cutting and Tool Design

Start/stopcontrols

Feed reverse

RPM (see notechangelevers

Headstock

Workholder

Cutting toolholder

Cutting tool

Workpiece (see below)

Tailstok

Leadscrew

Feerod

This machine tool is called an engine latheMachine tool

"lathe"

Workpiece

Depthof cut

D2Chip

NSCutting

tool

D1

Feed rate (ipm)

NoteThe rpm of the rotatingworkpiece is . lt establishes

the cutting speed V, At the

tool, according to = 10V/ D.

The depth of cut, , is equal to( – )/2.

The length of cut is the distancethe tool travels parallel to theaxis, .

N

N

d

D D

L

s

sp

1 2

V

Fig. 1.3 Turning a Hyndrical workpiece on a lathe requires you to select the

cutting need, feed and depth of cut.

Figure 1.3 shows a typical machine tool for the turning process, a lathe. Workpieces

are held in workholding devices. In this example, a three-jaw chuck is used to hold the

workpiece and rotate it against the tool. The chuck is attached to the spindle, which is

driven through gears by the motor.

Turning, Single Point and Box Tools

Material Hard- Condition Depth High Speed Steel Carbide Tool

ness of Tool Uncoated Coated

Cut* Speed Feed Material Brazed able Grade Grade

in fpm ipr AISI fpm fpm ipr C fpm ipr C

Bhn mm m/min mm/t ISO m/min m/min mm/r ISO m/min mm/r ISO

1. Free machining Hot Rolled, .040 160 .008 M2.M3 500 610 .007 C-7 925 .007 CC-7

Carbon Steels, Normalized, .150 125 .015 M2, M3 390 480 .020 C-6 600 .015 CC-6

Wrought (cont.) Annealed, .300 100 .020 M2, M3 310 375 .030 C-6 500 .020 CC-6

Medium Carbon 225 Cold Drawn .625 80 .030 M2, M3 .240 290 .040 C-6 — — —

Leaded to or 1 49 .20 S4, S5 150 185 .18 P10 280 .18 CP10

(cont.) 275 Quenched 4 38 .40 S4, S5 120 145 .50 P20 185 .40 CP20

(materials listed and 8 30 .50 S4, S5 95 115 .75 P30 150 .50 CP30

on proceding Tempered 16 24 .75 S4, S5 73 88 1.0 P40 — — —

page)

Metal Machining 5

Hot .040

Rolled, .150 105 .015 T15, M42 460 545 .007 C-7 825 .007 CC-7

275 Annealed .625 — — — — — — — — — —

to or 1 41 .18 S9, S11 140 165 .18 P10 250 .18 CP10

325 Quenched 4 32 .40 S9, S11 105 130 .50 P20 160 .40 CP20

and 8 26 .50 S9, S11 84 100 .75 P30 130 .50 CP30

Tempered 16 — — — — — — — — — —

.040 100 .007 T15, M42 390 480 .007 C-7 725 .007 CC-7

.150 80 .015 T15, M42 300 375 .020 C-6 475 .015 CC-6

325 Quenched .300 65 .020 T15, M42 230 290 .030 C-6 375 .020 CC-6

to and .625 — — — — — — — — — —

375 Tempered 1 30 .18 S9, S11 120 145 .18 P10 220 .18 CP10

4 24 .40 S9, S11 70 88 .75 P30 115 .50 CP20

8 20 .50 S9, S11 70 88 .75 P30 115 .50 CP30

16 — — — — — — — — — —

.040 70 .007 T15, M42 325 400 .007 C-7 600 .007 CC-7

.150 55 .015 T15, M42 250 310 .020 C-6 400 .015 CC-6

375 Quenched 300 35 .020 T15, M42 200 240 .030 C-6 325 .020 CC-6

to and .625 — — — — — — — — — —

425 Tempered 1 21 .18 S9, S11 100 120 .18 P10 185 .18 CP10

4 17 .40 SP, S11 76 95 .50 P20 120 .40 CP20

8 14 .50 S9, S11 60 73 .75 P30 100 .50 CP30

16 — — — — — — — — — —

2. Carbon Steels, .040 185 .007 M2, M3 535 700 .007 C-7 1050 .007 CC-7

Wrought Hot .150 145 .015 M2, M3 435 540 .020 C-6 700 .015 CC-6

Low Carbon Rolled, .300 115 .020 M2, M3 340 420 .030 C-6 550 .020 CC-6

85 Normalized, .625 90 .030 M2, M3 265 330 .040 C-6 — — —

1005 1010 1020 to Annealed 1 56 .18 S4, S5 165 215 .18 P10 320 .18 CP10

1006 1012 1023 125 or Cold 4 44 .40 S4, S5 135 165 .50 P20 215 .40 CP20

1008 1015 1025 Drawn 8 35 .50 S4, S5 105 130 .75 P30 170 .50 CP30

1009 1017 16 27 .75 S4, S5 81 100 1.0 P40 — — —

.040 150 .007 M2, M3 485 640 .007 C-7 950 .007 CC-7

Hot .150 125 .015 M2, M3 410 500 .020 C-6 625 .015 CC-6

Rolled, .300 100 .020 M2, M3 320 390 .030 C-6 500 .020 CC-6

125 Normalized, .625 80 .030 M2, M3 245 305 .040 C-6 — — —

to Annealed 1 46 .18 S4, S5 150 195 .18 P10 290 .18 CP10

175 or Cold 4 38 .40 S4, S5 125 150 .50 P20 190 .40 CP20

Drawn 8 30 .50 S4, S5 100 120 .75 P30 150 .50 CP20

16 24 .75 S4, S5 75 95 1.0 P40 — — —

.040 145 .007 M2, M3 460 570 .007 C-7 850 .007 CC-7

Hot .150 115 .015 M2, M3 385 450 .020 C-6 550 .015 CC-6

Rolled, .300 95 .020 M2, M3 300 350 .030 C-6 450 .020 CC-6

175 Normalized, 625 75 .030 M2, M3 235 265 .040 C-6 — — —

to Annealed 1 44 .18 S4, S5 140 175 .18 P10 260 .18 CP10

225 or Cold 4 35 .40 S4, S5 115 135 .50 P20 170 .40 CP20

Drawn 8 29 .50 S4, S5 90 105 .75 P30 135 .50 CP30

16 23 .75 S4. S5 72 81 1.0 P40 — — —

Material Hard- Condition Depth High Speed Steel Carbide Tool

ness of Tool Uncoated Coated

Cut* Speed Feed Material Brazed able Grade Grade

in fpm ipr AISI fpm fpm ipr C fpm ipr C

Bhn mm m/min mm/t ISO m/min m/min mm/r ISO m/min mm/r ISO

6 Metal Cutting and Tool Design

.040 125 .007 M2, M3 410 510 .007 C-7 750 .007 CC-7

.150 95 .015 M2, M3 360 400 .020 C-6 500 015 CC-6

Annealed .300 75 .020 M2, M3 285 315 .030 C-6 400 .020 CC-6

225 or .625 60 .030 M2, M3 220 240 .040 C-6 — — —

to Cold 1 38 .18 S4, S5 125 155 .18 P10 230 .18 CP10

275 Drawn 4 29 .40 S4, S5 110 120 .50 P20 150 .40 CP20

8 23 .50 S4, S5 87 95 .75 P30 120 .50 CP30

16 18 .75 S4, S5 67 73 1.0 P40 — — —

Fig. 1.4 Examples of a table for selection of speed and feed for turning

Once cutting speed V has been selected, equation is used to determine the spindle

rpm, Ns. The speed and feed can be used with the DOC to estimate the metal removal

rate of the process, or MRR. For turning, the MRR is

MRR 125 f, d

This is an approximate equation for MRR. For turning, MRR values can range

from 0.1 to 600 in.3/min. The MRR can be used to estimate the horsepower needed to

perform a cut, as will be shown later. For most processes, the MRR equation can be

Cuttin

g s

peed:

fpm

L

d

D2

(d) Depth of cut

V

Fr

Feed. in./rev

Turning

Speed, stated in suface feet per minute(sfpm), is the peripheral speed at thecutting edge. Feed per revolution inturning is a linear motion of the toolparallel tothe rotating axis of theworkpiece. The depth of cutreflects the third dimension.

= length of cutL

T = L + A / f Nm r s

D1

NS

Machined surface

Boring bar

D2

d

fr

Tool

Boring

Enlaging hole of diameter D to

diameter D . Boring can be done

with multiple cutting tools. Feed ininches per revolution, f .

1

2

r

Material Hard- Condition Depth High Speed Steel Carbide Tool

ness of Tool Uncoated Coated

Cut* Speed Feed Material Brazed able Grade Grade

in fpm ipr AISI fpm fpm ipr C fpm ipr C

Bhn mm m/min mm/t ISO m/min m/min mm/r ISO m/min mm/r ISO

Metal Cutting and Tool Design By AshokKumar Singh

Publisher : Vayu Education ISBN : 9789383758210 Author : Ashok KumarSingh

Type the URL : http://www.kopykitab.com/product/3218

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