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TEXTBOOK OF
PRODUCTION ENGINEERING
SECOND EDITION
K.C. JAIN
FormerlySenior Professor
Prestige Institute of Engineering and Science, Indore
Director, Govindram Seksaria Institute of Management and Research, Indore
and
Dean, Faculty of Industrial Technology
Rajiv Gandhi University of Technology, Bhopal
A.K. CHITALE
Formerly -
Director and Academic Advisor
Govindram Seksaria Institute of Management and Research, Indore
PHI Learning PutaO© fcuMDelhi-110092
2014
Contents
Preface xxiii
Preface to the First Edition xxxi
Parti METAL CUTTING
1 Introduction to Materials and Processes 3-23
1.1 Materials and Their Necessity for Engineering Application 3
1.2 Types of Materials 4
1.2.1 Metallics 4
1.2.2 Polymers ........ 5
1.2.3 Ceramics 6
1.2.4 Composites 6
1.2.5 Other Materials 7
1.3 Overview of Manufacturing Processes 9
1.3.1 Basic or Conventional Processes 9
1.4 Constructional Features of Basic Machines 19
Review Questions 22
2 Metal Cutting Tools: Basic Concepts 24-49
2.1 Definition of Metal Cutting Tool 24
2.2 Classification of Metal Cutting Tools 24
2.2.1 Single-point Cutting Tools 24
2.2.2 Multi-point Cutting Tools 27
2.2.3 Form Tools 27
v
Vi CONTENTS
2.3 Pre-requisites of Cutting Tools 27
2.4 Standard Angles of Cutting Tool 28
2.4.1 Rake 28
2.4.2 Side Relief 29
2.4.3 End Relief 30
2.4.4 Recommended Rake and Relief Angles 30
2.4.5 Nose Radius 30
2.4.6 Tool Holder Angle 31
2.4.7 Flat or Drag 31
2.4.8 Clearance Angle 31
2.4.9 Side Cutting Edge 31
2.4.10 End Cutting Edge 32
2.4.11 Nose Angle and Angles in Normal Plane 33
2.5 Working Angles 33
2.5.1 Setting Angle 33
2.5.2 Entering Angle 33
2.5.3 True Rake Angle 34
2.5.4 Cutting Angle 34
2.5.5 Lip Angle 34
2.5.6 Working Relief Angle 34
2.6 Cutting Tool Nomenclature Systems 34
2.6.1 British Maximum Rake System 34
2.6.2 American System (ASA System) 35
2.6.3 German System (DIN System) 35
2.6.4 Normal Rake System 35
2.7 Reference Planes 36
2.7.1 Coordinate System of Reference Planes 36
2.7.2 Orthogonal System of Reference Planes or Orthogonal Rake
System (ORS) or International Orthogonal System (ISO) 36
2.7.3 Transformation from ASA System to ISO System 37
2.8 Cutting Tool Signature 39
2.9 Geometry of Cutting Tools 40
2.10 Factors Affecting Tool Geometry 40
2.11 Illustrative Examples on Tool Geometry 40
Review Questions 49
3 Cutting Tool Materials 50-66
3.1 Introduction 50
3.2 Requirements or Characteristics of a Tool Material 50
3.3 Types of Tool Materials 51
3.3.1 Plain Carbon Steels 51
3.3.2 Low Alloy Steels 52
3.3.3 High Speed Steels 52
3.3.4 Non-ferrous Cast Alloys (Super High Speed Tools) 52
3.3.5 Cemented Carbides 53
CONTENTS Vii
3.3.6 Ceramic Tool Materials 57
3.3.7 Cermets 58
3.3.8 Diamonds 58
3.3.9 Abrasives 58
3.4 Characteristics and Uses of Diamond Tools 58
3.4.1 General 58
3.4.2 Classification 59
3.4.3 Origin 59
3.4.4 Special Characteristics 59
3.4.5 Relation to Metal Cutting Process 59
3.4.6 Machining Characteristics 60
3.5 Comparison of Cutting Tool Materials 61
3.6 Non-ferrous Cutting Tool Materials 61
3.7 Non-metallic Cutting Tool Materials 63
3.7.1 Plastics 63
3.7.2 Rubber 63
3.7.3 Wood 63
3.7.4 Hard Board 63
Review Questions 64
4 Design of Metal Cutting Tools 67-77
4.1 Introduction 67
4.2 Elements of Cutting Tool Design 67
4.3 Forces Acting on Cutting Tools 68
4.3.1 Force of Resistance to Cutting 68
4.3.2 Force of Drilling 69
4.3.3 Design of Single-point Cutting Tool 70
4.4 Brazed Tool Seats 72
4.5 Cut-off Tools 72
4.6 Boring Tools 73
4.7 Brazed Tipped Tools 73
4.8 Mechanically Held Tipped Tools 74
4.9 Diamond Tools 74
4.9.1 Brazed Diamond Tool 75
4.9.2 Mechanically Clamped Diamond Tool 75
4.10 Form Tools and Their Design 75
4.10.1 Circular and Flat Form Tool 75
Review Questions 77
5 Theory of Metal Cutting 78-121
5.1 Historical Development 78
5.2 Metal Cutting Defined 78
5.3 Characteristics of Metal Cutting 79
5.4 Representation of Metal Cutting Process 79
5.5 Orthogonal and Oblique Cutting 79
Viii CONTENTS
5.6 Difference between Orthogonal and Oblique Cutting 80
5.7 Mechanism of Chip Formation 81
5.8 Curling of Chip 82
5.9 Geometry of Chip Formation 82
5.10 Methods Used for Determining Chip Geometry 83
5.11 Classes of Chips 83
5.11.1 Discontinuous Chips 83
5.11.2 Inhomogeneous Chips 84
5.11.3 Continuous Chips 84
5.11.4 Fractured Chips 85
5.12 Effect of Various Factors on Chip Formation or Metal Cutting Characteristics 85
5.13 Methods of Reducing Friction 86
5.14 Physical Aspects,of Chip Control and Chip Breakers 86
5.14.1 Chip Control Through Tool Grinding 86
5.14.2 Chip Control Through Chip Breakers 87
5.15 Velocity Relationships in Orthogonal Cutting—Merchant's Analysisof Metal Cutting Kinematics 91
5.16 Chip Thickness Ratio 92
5.17 Forces Acting on a Cutting Tool 94
5.18 Principle of Minimum Energy Applied to Metal Cutting—Merchant'sShear Angle Relation 96
5.19 Stress and Strain in Chip 99
5.20 Shear and Strain Rate 99
5.21 Energy Consideration in Metal Cutting 100
5.22 Stress and Strain Distributions in Plane Flow—Lee and Shaffer's Model 101
5.23 Different Theories of Shear Angle Relationship 104
Review Questions 119
6 Theory of Multipoint Machining 122-154
6.1 Introduction 122
6.2 Mechanism of Drilling 123
6.3 Torque and Thrust in Drilling Processes at Lips and Chisel 124
6.4 Mechanics of Metal Cutting in Chisel Edge Zone of Twist Drill 125
6.4.1 Analysis for Cutting Zone 126
6.4.2 Thrust Due to Chisel Edge Indentation 128
6.5 Use of Formulae for Torque and Thrust at Lips of Twist Drill 129
6.6 Milling 130
6.6.1 Determination of Undeformed Chip Length 130
6.6.2 Feed Rate and Cutter Wear 132
6.6.3 Depth of Cut and Cutter Wear 132
6.6.4 Chip Thickness 132
6.6.5 Schlesinger's Formula 133
6.6.6 Cutting Forces and Power 134
6.6.7 Total Force Acting on a Cutter 135
6.6.8 Work Done in Milling 136
6.6.9 Relationship between Face and Peripheral Milling 137
CONTENTS iX
6.7 Mechanism of Grinding 137
6.7.1 Undeformed Chip Length 138
6.7.2 Maximum Chip Thickness in Cylindrical Grinding 141
6.7.3 Grinding Kinetics 143
6.8 Power in Broaching 144
Review Questions 154
7 Heat in Metal Cutting and Temperature Measurement 155-192
7.1 Introduction 155
7.2 Computation of Temperatures in Orthogonal Cutting 156
7.2.1 Stationary Heat Source—Friction Slider 156
7.2.2 Shear Plane Temperature 160
7.2.3 Tool Face Temperature 162
7.2.4 Energy Balance 166
7.3 Cutting Tool Temperature by Dimensional Analysis 167
7.3.1 Introduction 167
7.3.2 Dimensional Analysis of Tool Temperature : 167
7.3.3 Comparison with Experimentally Obtained Expressions 171
7.4 Heat and Temperature in Milling 173
7.5 Heat and Temperature in Drilling 173
7.6 Heat and Temperature in Grinding 176
7.6.1 Heat in Grinding 176
7.6.2 Energy Considerations 178
7.6.3 Thermodynamic Background for Thermal Aspect in Grinding 178
7.6.4 Calculation of Grinding Temperature 180
7.7 Experimental Techniques of Temperature Measurement 182
7.7.1 Orthogonal and Oblique Cutting 182
7.7.2 Arrangement for Measurement by Thermocouple 182
7.7.3 Calibration Procedure 184
7.7.4 Radiation Method of Temperature Measurement 186
7.7.5 Imbedded Thermocouple Method of Temperature Measurement 187
7.8 Measurement of Temperature in Milling 188
7.9 Measurement of Temperature in Drilling 189
7.10 Measurement of Temperature in Grinding 190
Review Questions 191
8 Dynamometry 193-219
8.1 Introduction 193
8.2 Forces at the Cutting Edge 193
8.3 Desirable Characteristics of a Dynamometer 194
8.4 Strain and Strain Measurement 195
8.5 Need for Strain Measurement 195
8.6 Properties of an Ideal Strain Gauge 195
8.7 Mechanical Strain Measurement 196
8.8 Optical Strain Measurement 196
X CONTENTS
8.9 Electrical Strain Measurement 196
8.10 Uses of Strain Gauges 197
8.11 Survey of Various Types of Dynamometers 198
8.11.1 Mechanical Type 199
8.11.2 Hydraulic Type 199
8.11.3 Pneumatic Type 200
8.11.4 Optical Type 200
8.11.5 Electrical Type 200
8.12 Use of Electrical and Electronic Transducers 203
8.12.1 Electrical Transducer Tube 203
8.12.2 Differential Transformer 203
8.12.3 Unbounded Wire Resistance Strain Gauge 203
8.12.4 Bonded Strain Gauges 204
8.13 Strain Gauge Force and Torque Transducer 204
8.13.1 Strain Gauge Bridge Circuit 205
8.13.2 Wheatstone Bridge 206
8.14 Practical Applications of Resistance Gauges 208
8.15 Bonding Techniques 211
8.16 Surface Preparation for Bonding Strain Gauges 211
8.17 Nitrocellulose Cement 212
8.18 Epoxy Cements 212
8.19 Strain Gauge Lathe Dynamometer 212
8.20 Turning Dynamometers 213
8.20.1 Turning Dynamometer Based on Basic Principle 213
8.20.2 Another Type of Turning Dynamometer 214
8.21 Three-component Lathe Tool Dynamometer 215
8.22 Milling and Grinding Dynamometers 216
8.22.1 Milling Dynamometers 217
8.22.2 Grinding Dynamometer 218
8.23 Response Curve of Dynamometer 218
Review Questions 219
9 Tool Failures and Tool Life 220-246
9.1 Tool Failure Defined 220
9.2 Criterion of Tool Failure 220
9.3 Types of Tool Failure 221
9.3.1 Temperature Failure 221
9.3.2 Mechanical Chipping 222
9.3.3 Built-Up Edge (BUE) 222
9.3.4 Spalling or Crumbling 223
9.4 Tool Wear (Microscopic Wear) 223
9.4.1 Effects of Tool Wear 223
9.4.2 Types of Tool Wear 223
9.5 Causes or Mechanisms of Wear 225
9.5.1 Abrasion 225
CONTENTS Xi
9.5.2 Adhesion 226
9.5.3 Diffusion 227
9.5.4 Electrochemical 228
9.6 Measurement of Tool Wear 228
9.7 Tool Life Definition 228
9.8 Tool Life Specifications 228
9.9 Measurement of Tool Life 229
9.9.1 Expected Tool Life 229
9.9.2 General Empirical Relationship between Cutting Speed,Tool Life, Feed, and Depth of Cut 229
9.9.3 Formula Connecting Tool Life, Cutting Speed, Chip Thickness and
Length of Tool Engagement 230
9.9.4 Equation Incorporating the Effect of Size of Cut 230
9.10 Factors Affecting Tool Life 230
9.10.1 Cutting Speed 231
9.10.2 Effect of Feed Rate and Depth of Cut 231
9.10.3 Microstructure of Workpiece 232
9.10.4 Effect of Workpiece Hardness 232
9.10.5 Effect of Tool Material 233
9.10.6 Rigidity of Workpiece Machine Tool System 233
9.10.7 Nature of Cutting 233
9.10.8 Cutting Fluids and Tool Life 233
9.10.9 Effect of Shape and Tool Angles on Tool Life 233
Review Questions 245
10 Machinability 247-252
10.1 Machinability Defined 247
10.2 Evaluation of Machinability 247
10.2.1 Tool Life 248
10.2.2 Chip Control 249
10.2.3 Power Consumption 249
10.2.4 Surface Finish 249
10.3 Factors Affecting Machinability 250
10.3.1 Microstructure 250
10.3.2 Strength 250
10.3.3 Strength at Elevated Temperature 250
10.3.4 Coefficient of Thermal Dispersion 251
10.3.5 Built-up Edge Formation 251
10.3.6 Work Hardening 251
10.3.7 Effect of Alloying Elements 251
10.3.8 Heat Treatment 252
10.3.9 Tool Geometry 252
10.3.10 Cutting Fluid 252
10.3.11 Machine Tool, Tool and Work Factors 252
10.4 Machinability Index 252
Review Questions 252
XH CONTENTS
11 Economics of Metal Machining 253-260
11.1 Cost Analysis and Economics 253
11.2 Indexable Insert System 257
11.3 Brazed Carbide Tool 258
11.4 Variation of Costs with Speed for Different Tools 258
Review Questions 260
12 Metal Cutting and Metal Working Fluids 261-276
12.1 Definition of Cutting Fluids 261
12.2 Functions of Cutting Fluids 261
12.3 Advantages of Cutting Fluid Applications 262
12.4 Characteristics of Good Cutting Fluid 262
12.5 Theory of Cutting Fluid 263
12.6 Action of Cutting Fluids as Lubricant 263
12.7 Cutting Fluids and Tool Life 264
12.8 Application of Metal Working Fluids 264
12.9 Type of Cutting Fluids 265
12.9.1 Solid Cutting Fluids 265
12.9.2 Liquid Cutting Fluids 265
12.10 Synthetic or Chemical Cutting Fluids 268
12.10.1 Types of Synthetic Cutting Fluids 269
12.10.2 Commonly Used Chemical Constituent Fluids 269
12.10.3 Advantages of Synthetic Fluids 269
12.10.4 Disadvantages of Synthetic Fluids 269
12.11 Gaseous Cutting Fluids 270
12.12 Extreme Pressure (EP) Lubrication Mechanism in Metal Cutting 270
12.12.1 Advantages of EP 270
12.12.2 Conditions of Use of EP 271
12.12.3 Examples of EP 271
12.13 Criteria of Selection of Cutting Fluids 271
12.13.1 Disadvantages of Using Cutting Fluids 271
Review Questions 275
Part II MACHINE TOOLS
13 Introduction to Machine Tools 279-283
13.1 Machine Tool—Definition 279
13.1.1 Machine Tool Design Requirements 279
13.2 Present Trend of Design Optimisation 280
13.3 Elements of Machine Tools 280
13.4 Classification of Metal Cutting Machine Tools 280
13.5 Machine Tool Industry—Progress in India 281
13.6 Common Features of Machine Tools 282
CONTENTS XiH
13.7 Selection of Machine Tools 282
13.8 Systems for Control of Machine Tools 283
Review Questions 283
14 Design of Machine Tool Beds 284-293
14.1 Introduction 284
14.2 Factors in Design of Beds 285
14.2.1 Strength 285
14.2.2 Volume to Weight Ratio 286
14.2.3 Vibration Response 289
14.2.4 Damping 290
14.2.5 Vibration and Chatter 290
14.3 Calculation for Design of Beds 292
14.3.1 Material of Beds 292
14.3.2 Shape of Beds 293
Review Questions 293
15 Design of Machine Tool Guides and Ways 294-309
15.1 Introduction 294
15.2 Working Surface of Guides 295
15.2.1 Flat Guideways 295
15.2.2 Inverted V-Shaped Guideways 295
15.2.3 Combined Sliding Guideways (Flat and Inverted V) 296
15.2.4 Dovetail Guideways 296
15.2.5 Cylindrical or Round Guideways.... 297
15.2.6 Roller Antifriction Guideways 297
15.2.7 Mixed Guideways 298
15.3 Guide and Slideway Material 299
15.4 Pressure on Sliding Ways 299
15.4.1 Pressure Calculation 299
15.4.2 Considerations for Ballways 302
15.4.3 Roller and Ball Guideways 303
15.5 Lubrication and Protection of Guideways 303
15.5.1 Lubrication Theory 303
15.5.2 Protection of Guideways 308
Review Questions 309
16 Design of Feed Power Mechanism and Screw 310-327
16.1 Translatory Motion Mechanisms 310
16.1.1 Rack Gear and Rack-toothed Sector 310
16.1.2 Worm and Worm Rack 310
16.1.3 Nut and Screw 310
16.2 Design of a Screw 311
16.2.1 Strength of a Screw 312
16.2.2 Rigidity Checking 313
XiV CONTENTS
16.3 Kinematic Pair—Link Mechanisms 315
16.4 Kinematic Pair—Cam Follower and Link 315
16.5 Hinged Leverage Systems 316
16.6 Mechanisms for Intermittent Motions 317
16.7 Ratchet and Pawl 318
16.8 Safety Devices on Metal Cutting Machines 319
16.9 Spindles and Shafts 319
16.10 Edge Effect 320
16.11 Wear 321
16.12 Vibration of Spindles and Shafts 322
16.13 Spindle Nose 323
16.14 Supports of Spindles and Shafts 324
16.15 Antifriction Bearings 324
16.15.1 Selection of Ball and Roller Bearings 324
16.15.2 Mounting of Antifriction Bearings 325
Review Questions 327
17 Design of Machine Tool Gear Box 328-364
17.1 Introduction—Machine Tool System 328
17.1.1 Drives and Regulation of Motion on Metal-Cutting Machines 328
17.1.2 Various Motions of Machine Tool System 328
17.2 Fundamentals of Mechanical Regulation 329
17.3 Development of Series of Numbers 332
17.4 Ray Diagram for Overlapping Speeds 340
17.5 Ray Diagrams for Return Step of Speed 340
17.6 Kinematic Arrangement for Two or More Speeds at Input Shaft 341
17.7 Determination of Number of Teeth on Gears of Stepped Control Mechanisms 342
17.7.1 Method of Least Common Multiple 342
17.7.2 Method of Difference 345
17.7.3 Constructive Method 346
17.8 Practical Aspects in the Design of Drives 352
17.9 Mechanical Regulation of Drives 352
17.9.1 Belt and Cone Pulley Drive 353
17.9.2 Belt Pulley Drive with Back Gear 355
17.9.3 Gearbox Drives 358
Review Questions 364
18 Stepless Regulation of Speeds 365-419
18.1 Introduction 365
18.1.1 Classification 365
18.1.2 Reversing of Motion in Machine Tools 366
18.1.3 Mechanical Regulation 366
18.1.4 Methods of Increasing Range of Regulation 370
18.2 Hydraulic Drives for Speed Regulation 370
18.2.1 Introduction 370
CONTENTS XV
18.2.2 Advantages and Disadvantages of Hydraulic Drives 372
18.2.3 Requirement of Fluids Applied in Hydraulic Systems 372
18.2.4 Mineral Oils as Fluids for Hydraulic Systems 372
18.2.5 Properties of Hydraulic Oils 373
18.2.6 Efficiency in Stages 374
18.2.7 Cylinders for Hydraulic Drive Pumps 374
18.2.8 Piston and Piston Rod Seals 377
18.2.9 Pumps for Hydraulic Drives of Machine Tools 379
18.2.10 Throttle Valves for Hydraulic Drives 382
18.2.11 Fluid Control Valves 384
18.2.12 Resistance to Flow Due to Obstruction 385
18.2.13 Rotary Control Valves 386
18.2.14 Hydraulic Piping and Its Joints 386
18.2.15 Cross-section Calculation 387
18.2.16 Speed Control 388
18.2.17 Design of the Components of Grinding Machine Hydraulic Drive 393
18.2.18 Hydraulic Drive for Rotary Motion 397
18.2.19 Advantages and Disadvantages of Hydraulic Drive 397
18.3 Electrical and Electronic Regulation of Speeds 398
18.3.1 Introduction 398
18.3.2 Power Required by a Machine Tool 398
18.3.3 Selection of Motor for Speed Regulation 400
18.3.4 Classification of Drives 400
18.3.5 Characteristics of Electric Motors 400
18.3.6 Speed Regulation by Amplidyne 412
18.3.7 Emotrol System of Speed Regulation (Electronic Motor Control) 412
18.3.8 Selsyn System of Speed Regulation—The Word Sel-Syn Stands
for Self-Synchronous Device 412
18.3.9 Braking 413
18.3.10 Analysis of Braking 413
18.3.11 Starting and Stopping of Motors 417
18.3.12 Clutch Control 417
18.3.13 Relays 418
Review Questions 419
19 Machine Tool Vibrations 420-433
19.1 Introduction 420
19.2 Types of Machine Tool Vibration 420
19.2.1 Forced Vibration 421
19.2.2 Self-excited Vibration 422
19.3 Causes of Chatter 423
19.3.1 Mathematical Analysis of Chatter Vibrations 425
19.3.2 Chatter Vibrations 428
19.4 Closed Loop Representation of the Metal Cutting Process 430
19.5 Vibration Elimination 432
Review Questions 433
XVI CONTENTS
20 Mechanization and Automation 434-478
20.1 Machine Tools for Quantity Production 434
20.2 Semi-automatic Multi-tool Centre Lathes 434
20.3 Principal Parts of Capstan and Turret Lathes 436
20.4 Automation Mechanisms on Capstan and Turret Lathes 439
20.4.1 Indexing Mechanism 439
20.4.2 Bar Feeding Mechanism 440
20.4.3 Bar Holding Mechanism 440
20.5 Tooling Layout for Capstan and Turret Lathes 442
20.6 Single-spindle Automatic Lathes 447
20.7 Hydraulic Copying Systems 457
20.8 Electric Copying System 459
20.9 Transfer Machines 460
20.9.1 Transfer Machines and Automated Flow Lines 460
20.9.2 Automated Flow Lines 460
20.9.3 Classification of Transfer Lines 461
20.9.4 Elements of Transfer Lines 462
20.9.5 Transfer Mechanisms 472
20.9.6 Selection of Transfer Devices 474
20.9.7 Methods of Work Transfer 475
20.9.8 Arrangement of Transfer Lines 477
Review Questions 478
21 Numerical and Computer Numerical Controlled Machines .... 479-521
21.1 Introduction 479
21.2 History of NC 480
21.3 Working Principle of NC Machine 482
21.4 Basic Elements of NC System 482
21.5 Coordinate System in NC Machine Tools 488
21.6 Procedure in NC 490
21.7 Structure of NC Program 491
21.8 Tape Format 492
21.9 Types of Motion Control System in NC 496
21.10 Criteria for Classification of Numerical Controlled Systems 497
21.11 Advantages and Limitations of NC Machines 503
21.12 Computers and NC Machines 505
21.13 Computer Aided Part Programming (on CNC Lathe Machine
Having FANUC Control) 508
21.14 Part Programming in APT Example 512
21.15 Miscellaneous and Preparatory Functons and their Codes for CNC Milling 513
Review Questions 520
Objective Type Questions 521
CONTENTS XVii
22 Gear Cutting, Broaching and Thread Cutting 522-541
22.1 Introduction 522
22.2 Various Methods of Gear Production 522
22.3 Various Kinds of Gears 523
22.4 Involute Gear Tooth Fundamentals 524
22.5 Gear Teeth Manufacturing 524
22.6 Broaching Operation 531
22.7 Production of Screw-Threads 535
22.7.1 Screw Thread Geometry and Chasing of Screw Threads 536
22.7.2 Internal Screw Threads 538
22.7.3 Thread Rolling 538
Review Questions 541
Part HI PRECISION MEASUREMENT AND
MANUFACTURING
23 Metrology and Precision Measurement 545-615
23.1 Linear Precision Measurement 545
23.1.1 External Micrometer 545
23.1.2 Vernier Calipers 547
23.2 Length Standards 548
23.3 Points of Support 550
23.4 Interferometry 551
23.5 Calibration of Length Standards 553
23.6 Slip Gauges—BS 888 and BS 4311 555
23.7 Some Sources of Error in Linear Measurement 555
23.8 Angular Measurement 556
23.9 Measurement of Small Linear Displacements 557
23.10 Optical Magnification of Workpiece 563
23.11 Measurement of Small Angular Displacements 564
23.12 Limits, Fits and Tolerance 565
23.13 Geometrical Tolerances 571
23.14 Screw Threads 572
23.14.1 Tolerance for ISO Metric Threads 573
23.14.2 Magnitudes of Tolerance and Deviation 574
23.15 Limit Gauging 576
23.15.1 Gauge Tolerances 577
23.16 Screw Gauge 579
23.16.1 Gauging Principles 580
23.16.2 Screw-thread Gauging 582
23.17 Surface Finish and Its Measurement 586
23.17.1 Surface Finish Terminology 586
23.17.2 Evaluation of Surface Roughness 588
xviii CONTENTS
23.17.3 Representation of Surface Roughness 589
23.17.4 Relationship of Surface Roughness to Manufacturing Process 589
23.17.5 Measurement of Surface Roughness 590
23.18 Testing of Machine Tools 595
23.18.1 Equipment Used for Testing 595
23.18.2 Test Procedures 596
23.18.3 Tests for Acceptance 596
Review Questions 602
24 Jigs and Fixtures 616-671
24.1 Definitions 616
24.2 Distinction between Jig and Fixture 617
24.3 Advantages 617
24.4 Principles of Design of Jigs and Fixtures 618
24.5 Design Procedure 619
24.6 Locations, 620
24.6.1 Factors Affecting Location 620
24.6.2 Principles of Location 620
24.6.3 Six-point Location of Rectangular Block 621
24.6.4 Types of Locators 621
24.6.5 Locating Devices and their Choice 621
24.7 Clamping 631
24.7.1 Functions of Clamps 631
24.7.2 Clamping Devices 631
24.7.3 Types of Clamps 632
24.7.4 Classification of Jig Bushes 645
24.8 Jig Base and Jig Feet 647
28.8.1 Jig Base 647
24.8.2 Jig Feet 647
24.9 Classification of Drill Jigs and Fixtures 648
24.9.1 Classification of Jigs 648
24.10 Classification of Fixtures 655
24.10.1 Milling Fixtures 656
24.10.2 Turning Fixtures 662
24.10.3 Grinding Fixtures 663
24.10.4 Broaching Fixtures 664
24.10.5 Assembly Fixtures 665
24.10.6 Welding Fixtures 665
24.10.7 Slotting Fixtures 666
24.10.8 Boring Fixtures 666
24.10.9 Miscellaneous Fixtures 666
24.11 Materials for Manufacturing of Jigs and Fixtures 666
24.12 Accuracy 668
24.13 Possible Ways of Avoiding Inaccuracies 668
24.14 Economic Aspects 669
Review Questions 670
CONTENTS XiX
Part IV METAL WORKING
25 Metal Working Processes 675-686
25.1 Definition 675
25.2 Types of Metal Working Processes 675
25.2.1 Cold Working 675
25.2.2 Hot Working 681
Review Questions 686
26 Theory of Metal Working Processes 687-713
26.1 Introduction 687
26.2 Methods of Plasticity Analysis of Manufacturing Processes 687
26.3 Forging Analysis Using Slab Method 689
26.4 Flat Rolling Analysis Using Slab Method 692
26.5 Deep Drawing Analysis Using Theory of Plasticity 695
26.6 Extrusion Analysis Using Slab Method 698
26.6.1 Particular Cases 699
26.7 Rolling 701
Review Questions 709
27 Press Tools and Their Design 714-770
^ 27.1 Introduction 714
27.2 Advantages 714
27.3 Types of Presses 715
27.3.1 Classification Based on Source of Power 715
27.3.2 Classification Based on Design of Frame 715
27.3.3 Classification Based on Actuation of Ram 715
27.3.4 Classification Based on Number of Slides 715
27.3.5 Classification Based on Intended Use 716
27.4 Design of Press Frame 717
27.4.1 Power Press Driving Mechanism 718
27.5 Methods of Punch Support 721
27.6 Methods of Die Support 721
27.7 Press Capacities 723
27.7.1 Tonnage Capacity 723
27.7.2 Catalogue Tonnage Rating 723
27.7.3 Rating of Hydraulic Presses 725
27.8 Press Operations 725
27.8.1 Cutting Operations 725
27.8.2 Non-Cutting Operations 726
27.9 Choice of Press 729
.
27.10 Design Fundamentals and Construction Features of Blanking, Piercingand Cropping Tools 729
27.10.1 Design Analysis 729
XX CONTENTS
27.10.2 General Notes on Press Tool Design 730
27.10.3 Press Tool and Its Parts 731
27.10.4 Important Design Consideration for Press Tool Clearances 734
27.10.5 Practical Die Clearance 736
27.10.6 Determination of Blanking Pressure 738
27.10.7 Determination of Press Size 738
27.10.8 Determination of Centre of Pressure 738
27.10.9 Design of Screws and Dowels 739
27.10.10 Design of Die Elements 744
27.10.11 Burr Height 750
27.10.12 Stripping Factors 750
27.10.13 Design of Punch 752
27.10.14 Shear Diagram for Punch Force Analysis 756
27.10.15 Punch Plate Design 757
27.10.16 Stripper Design 758
27.10.17 Knockout Design 762
27.10.18 Design of Bushes 764
27.10.19 Pneumatic Loading of Dies 764
27.10.20 Design of Press Tools with Ferrotic as Die Material 766
Review Questions 770
Part V MODERN METHODS OF MANUFACTURING
28 Unconventional Methods of Machining 773-815
28.1 Introduction 773
28.2 Definition of Unconventional Method 773
28.3 Major Unconventional Machining Processes 773
28.4 Process Capabilities of Unconventional Machining Processes 774
28.5 Ultrasonic Machining 776
28.6 USM Machine 777
28.7 Abrasive Jet Machining 779
28.8 Electrical Discharge Machining (EDM) 781
28.8.1 Theory and Analysis of EDM 781
28.8.2 Basics of EDM 782
28.8.3 Construction Features of EDM Machine 783
28.8.4 Wear Ratio 784
28.8.5 Metal Removal Rate (MRR) 785
28.8.6 Flushing the Electrode 786
28.9 Determination of Metal Removal Rate in Relaxation Circuit 786
28.10 Critical Resistance 788
28.11 Condition for Maximum Power 788
28.12 Wire Cut EDM 790
28.13 Electrochemical Machining (ECM) Process 792
28.14 Metal Removal Rate 796
28.15 Electrochemical or Electrolytic Grinding for Tools and Cutters 798
CONTENTS XXI
28.16 Electrochemical Deburring (ECD) 802
28.17 Laser Beam Machining Applications and Problems 803
28.18 Electron Beam Machining (EBM) 807
28.19 Electrolytic Sawing Mechanism and Machines 808
28.20 More Unconventional Processes 809
28.21 Hot Machining 809
Review Questions 811
29 Grinding and Other Abrasive Metal Removal Processes 816-869
29.1 Introduction 816
29.2 Grinding Wheel Variables 818
29.2.1 Types of Abrasives 818
29.2.2 Bond Materia] 819
29.2.3 Grade 821
29.2.4 Structure 821
29.3 Standard Codification of a Grinding Wheel 822
29.4 Selection of Grinding Wheels 822
29.5 Grinding Wheel Shapes 824
29.6 Wheel Dressing and Truing 824
29.6.1 Dressing and Truing Procedures 826
29.6.2 Rules for Using Diamond Tools 828
29.7 Balancing of Grinding Wheel 830
29.8 Recommended Wheel- and Work Speeds for Grinding 831
29.8.1 Recommended Wheel Speeds 831
29.8.2 Work Speeds 832
29.9 Types of Grinding Machines 832
29.9.1 Surface Grinding Machines 833
29.9.2 Cylindrical Grinders 834
29.9.3 Centreless Grinding 837
29.9.4 Other Grinding Machines and Processes 844
29.10 Honing Operation 847
29.10.1 Type of Honing Machines 849
29.10.2 Lapping 850
29.10.3 Superfmishing Operation 854
29.11 Snagging and Off-hand Grinding 855
29.11.1 Types of Snagging 855
29.11.2 Off-hand Grinding 857
29.12 Coated Abrasives for Other Industrial Applications 858
29.13 Centreless Belt Grinding 860
29.14 Tool Post Belt Grinding 862
29.15 Coated Abrasives 863
29.16 Trouble Shooting 864
29.17 Grinding Errors 865
Review Questions 868
References 871-878
Index 879-884
