Machining Technology – Machine Tools and Operations

Machining Technology – Machine Tools and Operations
اسم المؤلف
Helmi A. Yousef, Hassan El-Hofy
التاريخ
11 أغسطس 2018
المشاهدات
التقييم
(لا توجد تقييمات)
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Machining Technology – Machine Tools and Operations
Helmi A. Yousef
Hassan El-Hofy
Contents
Preface xix
Acknowledgments xxiii
Editors xxv
List of Symbols xxvii
List of Acronyms . xxxiii
Chapter 1 Machining Technology .1
1.1 Introduction .1
1.2 History of Machine Tools .1
1.3 Basic Motions in Machine Tools .5
1.4 Aspects of Machining Technology .5
1.4.1 Machine Tool .6
1.4.2 Workpiece Material .9
1.4.3 Machining Productivity .9
1.4.4 Accuracy and Surface Integrity . 10
1.4.5 Product Design for Economical Machining 10
1.4.6 Environmental Impacts of Machining 10
1.5 Review Questions 10
References 10
Chapter 2 Basic Elements and Mechanisms of Machine Tools 11
2.1 Introduction . 11
2.2 Machine Tool Structures . 13
2.2.1 Light- and Heavy-weight Constructions 17
2.3 Machine Tool Guideways 18
2.3.1 Sliding Friction Guideways . 18
2.3.2 Rolling Friction Guideways . 21
2.3.3 Externally Pressurized Guideways 22
2.4 Machine Tool Spindles 23
2.4.1 Spindle Bearings .23
2.4.2 Selection of Spindle-Bearing Fit .25
2.4.3 Sliding Friction Spindle Bearing .27
2.5 Machine Tool Drives .28
2.5.1 Stepped Speed Drives 28
2.5.1.1 Belting .28
2.5.1.2 Pick-Off Gears 30
2.5.1.3 Gearboxes 30
2.5.1.4 Stepping of Speeds According to Arithmetic Progression . 31
2.5.1.5 Stepping of Speeds According to Geometric Progression 32
2.5.1.6 Kinetic Calculations of Speed Gearboxes 35
2.5.1.7 Application of Pole-Changing Induction Motors 35
2.5.1.8 Feed Gearboxes 37
2.5.1.9 Preselection of Feeds and Speeds .39viii Contents
2.5.2 Stepless Speed Drives .40
2.5.2.1 Mechanical Stepless Drives .40
2.5.2.2 Electrical Stepless Speed Drive . 42
2.5.2.3 Hydraulic Stepless Speed Drive . 43
2.6 Planetary Transmission 44
2.7 Machine Tool Motors . 45
2.8 Reversing Mechanisms . 45
2.9 Couplings and Brakes .46
2.10 Reciprocating Mechanisms 48
2.10.1 Quick-Return Mechanism .48
2.10.2 Whitworth Mechanism 50
2.10.3 Hydraulic Reciprocating Mechanism .50
2.11 Material Selection and Heat Treatment of Machine Tool Components . 51
2.11.1 Cast Iron 51
2.11.2 Steels 52
2.12 Testing of Machine Tools . 53
2.13 Maintenance of Machine Tools 55
2.13.1 Preventive Maintenance 56
2.13.2 Corrective Maintenance 56
2.13.3 Reconditioning 56
2.14 Review Questions . 57
References 57
Chapter 3 General-Purpose Machine Tools 59
3.1 Introduction 59
3.2 Lathe Machines and Operations . 59
3.2.1 Turning Operations 59
3.2.2 Metal Cutting Lathes .60
3.2.2.1 Universal Engine Lathes .60
3.2.2.2 Other Types of General-Purpose Metal Cutting Lathes .69
3.3 Drilling Machines and Operations .70
3.3.1 Drilling and Drilling Allied Operations .70
3.3.1.1 Drilling Operation .70
3.3.1.2 Drilling Allied Operations 71
3.3.2 General-Purpose Drilling Machines . 74
3.3.2.1 Bench-Type Sensitive Drill Presses 74
3.3.2.2 Upright Drill Presses . 74
3.3.2.3 Radial Drilling Machines . 76
3.3.2.4 Multispindle Drilling Machines 76
3.3.2.5 Horizontal Drilling Machines for Drilling Deep Holes .77
3.3.3 Tool Holding Accessories of Drilling Machines .77
3.3.4 Work-Holding Devices Used on Drilling Machines .79
3.4 Milling Machines and Operations 82
3.4.1 Milling Operations 82
3.4.1.1 Peripheral Milling .82
3.4.1.2 Face Milling 84
3.4.2 Milling Cutters 84Contents ix
3.4.3 General-Purpose Milling Machines .86
3.4.3.1 Knee-Type Milling Machines .86
3.4.3.2 Vertical Bed-Type Milling Machines 88
3.4.3.3 Planer-Type Milling Machine .88
3.4.3.4 Rotary-Table Milling Machines 89
3.4.4 Holding Cutters and Workpieces on Milling Machines .90
3.4.4.1 Cutter Mounting 90
3.4.4.2 Workpiece Fixturing . 91
3.4.5 Dividing Heads .94
3.4.5.1 Universal Dividing Heads .94
3.4.5.2 Modes of Indexing 95
3.5 Shapers, Planers, and Slotters and Their Operations 99
3.5.1 Shaping, Planing, and Slotting Processes 99
3.5.1.1 Determination of v
cm in Accordance with the Machine Mechanism 101
3.5.2 Shaper and Planer Tools 102
3.5.3 Shapers, Planers, and Slotters 103
3.5.3.1 Shapers 103
3.5.3.2 Planers . 105
3.5.3.3 Slotters . 107
3.6 Boring Machines and Operations 107
3.6.1 Boring 107
3.6.2 Boring Tools 108
3.6.2.1 Types of Boring Tools . 108
3.6.2.2 Materials of Boring Tools . 109
3.6.3 Boring Machines . 109
3.6.3.1 General-Purpose Boring Machines . 109
3.6.3.2 Jig Boring Machines . 110
3.7 Broaching Machines and Operations 111
3.7.1 Broaching 111
3.7.1.1 Advantages and Limitations of Broaching . 112
3.7.2 The Broach Tool 113
3.7.2.1 Tool Geometry and Confguration 113
3.7.2.2 Broach Material 116
3.7.2.3 Broach Sharpening 116
3.7.3 Broaching Machines 116
3.7.3.1 Horizontal Broaching Machines . 117
3.7.3.2 Vertical Broaching Machines 118
3.7.3.3 Continuous Horizontal Surface Broaching Machines 118
3.8 Grinding Machines and Operations 119
3.8.1 Grinding Process . 119
3.8.2 Grinding Wheels . 122
3.8.2.1 Manufacturing Characteristics of Grinding Wheels 122
3.8.2.2 Grinding Wheel Geometry . 127
3.8.2.3 Mounting and Balancing of Grinding Wheels and Safety Measures . 127
3.8.2.4 Turning and Dressing of Grinding Wheels . 130
3.8.3 Grinding Machines 131
3.8.3.1 Surface Grinding Machines and Related Operations . 132
3.8.3.2 External Cylindrical Grinding Machines and Related Operations 133
3.8.3.3 Internal Grinding Machines and Related Operations . 136
3.8.3.4 Centerless Grinding Machines and Related Operations . 137x Contents
3.9 Microfnishing Machines and Operations 141
3.9.1 Honing . 141
3.9.1.1 Process Capabilities 142
3.9.1.2 Machining Parameters 144
3.9.1.3 Honing Machines 145
3.9.2 Superfnishing (Microhoning) . 145
3.9.3 Lapping 147
3.9.3.1 Machining Parameters 147
3.9.3.2 Lapping Machines . 148
3.10 Review Questions 154
References 156
Chapter 4 Thread Cutting . 157
4.1 Introduction . 157
4.2 Thread Cutting 159
4.2.1 Cutting Threads on the Lathe 160
4.2.2 Thread Chasing . 163
4.2.3 Thread Tapping . 164
4.2.4 Die Threading 168
4.2.4.1 Die Threading Machines 169
4.2.4.2 Die Threading Performance 172
4.2.5 Thread Milling 172
4.2.6 Thread Broaching 175
4.3 Thread Grinding . 175
4.3.1 Center-Type Thread Grinding . 175
4.3.2 Centerless Thread Grinding 177
4.4 Review Questions 178
References 179
Chapter 5 Gear Cutting Machines and Operations . 181
5.1 Introduction . 181
5.2 Forming and Generating Methods in Gear Cutting 183
5.2.1 Gear Cutting by Forming 184
5.2.1.1 Gear Milling 184
5.2.1.2 Gear Broaching . 188
5.2.1.3 Gear Forming by a Multiple-Tool Shaping Head 189
5.2.1.4 Straight Bevel Gear Forming Methods . 190
5.2.2 Gear Cutting by Generation 190
5.2.2.1 Gear Hobbing 190
5.2.2.2 Gear Shaping with Pinion Cutter 198
5.2.2.3 Gear Shaping with Rack Cutter 202
5.2.2.4 Cutting Straight Bevel Gears by Generation 202
5.3 Selection of Gear Cutting Method 207
5.4 Gear Finishing Operations 207
5.4.1 Finishing Gears Prior to Hardening 207
5.4.1.1 Gear Shaving .207
5.4.1.2 Gear Burnishing 211
5.4.2 Finishing Gears After Hardening 212
5.4.2.1 Gear Grinding . 212
5.4.3 Gear Lapping . 214Contents xi
5.5 Review Questions and Problems . 215
References 215
Chapter 6 Turret and Capstan Lathes . 217
6.1 Introduction . 217
6.2 Difference Between Capstan and Turret Lathes . 217
6.3 Selection and Application of Capstan and Turret Lathes . 219
6.4 Principal Elements of Capstan and Turret Lathes 219
6.4.1 Headstock and Spindle Assembly .220
6.4.2 Carriage/Cross-Slide Unit . 221
6.4.3 Hexagonal Turret . 221
6.4.3.1 Manually Controlled Machines 222
6.4.3.2 Automatically Controlled Headstock Turret Lathes .222
6.4.4 Cross-Sliding Hexagonal Turret 223
6.5 Turret Tooling Setups 223
6.5.1 Job Analysis .223
6.5.2 Tooling Layout .226
6.6 Review Questions 232
References 232
Chapter 7 Automated Lathes 233
7.1 Introduction . 233
7.2 Degree of Automation and Production Capacity 234
7.3 Classifcation of Automated Lathes 235
7.4 Semiautomatic Lathes .237
7.4.1 Single-Spindle Semiautomatics .237
7.4.2 Multispindle Semiautomatics 239
7.5 Fully Automatic Lathes . 241
7.5.1 Single-Spindle Automatic 241
7.5.1.1 Turret Automatic Screw Machine . 241
7.5.1.2 Swiss-Type Automatic . 252
7.5.2 Horizontal Multispindle Bar and Chucking Automatics .256
7.5.2.1 Special Features of Multispindle Automatics 256
7.5.2.2 Characteristics of Parallel- and Progressive-Action
Multispindle Automatic 258
7.5.2.3 Operation Principles and Constructional Features of a
Progressive Multispindle Automatic .260
7.6 Design and Layout of Cams for Fully Automatics .266
7.6.1 Planning a Sequence of Operation and a Tooling Layout .267
7.6.2 Cam Design .268
7.7 Review Questions and Problems .283
References 284
Chapter 8 Numerical Control and Computer Numerical Control Technology .285
8.1 Introduction .285
8.2 Coordinate System 290
8.2.1 Machine Tool Axes for NC .290
8.2.2 Quadrant Notation .292
8.2.3 Point Location .292
8.2.4 Zero Point Location .293xii Contents
8.2.5 Setup Point .293
8.2.6 Absolute and Incremental Positioning .293
8.3 Machine Movements in Numerical Control Systems .294
8.4 Interpolation .296
8.5 Control of Numerical Control Machine Tools 297
8.6 Components of Numerical Control Machine Tools 299
8.7 Tooling for Numerical Control Machines 302
8.8 Numerical Control Machine Tools .305
8.9 Input Units 308
8.10 Forms of Numerical Control Instructions 310
8.11 Program Format 311
8.12 Feed and Spindle Speed Coding . 312
8.12.1 Feed Rate Coding 312
8.12.2 Spindle Speed Coding . 314
8.13 Features of Numerical Control Systems . 314
8.14 Part Programming 316
8.15 Programming Machining Centers 320
8.15.1 Planning the Program 320
8.15.2 Canned Cycles . 322
8.16 Programming Turning Centers . 328
8.16.1 Planning the Program 328
8.16.2 Canned Turning Cycles . 331
8.17 Computer-Assisted Part Programming . 334
8.17.1 Automatically Programmed Tools Language 334
8.17.2 Programming Stages . 337
8.18 CAD/CAM Approach to Part Programming 339
8.18.1 Computer-Aided Design 339
8.18.2 Computer-Aided Manufacturing . 339
8.19 Review Questions .340
References 343
Chapter 9 Hexapods and Machining Technology .345
9.1 Introduction 345
9.2 Historical Background 345
9.3 Hexapod Mechanism and Design Features 348
9.3.1 Hexapod Mechanism .348
9.3.2 Design Features .349
9.3.2.1 Hexapods of Telescopic Struts (Ingersoll System) 349
9.3.2.2 Hexapods of Ball Screw Struts (Hexel and Geodetic System) . 352
9.4 Hexapod Constructional Elements . 354
9.4.1 Strut Assembly 354
9.4.2 Sphere Drive 354
9.4.3 Bifurcated Balls . 356
9.4.4 Spindles . 357
9.4.5 Articulated Head . 359
9.4.6 Upper Platform 359
9.4.7 Control System 361
9.5 Hexapod Characteristics . 362
9.6 Manufacturing Applications .366Contents xiii
9.7 Review Questions .368
References 369
Chapter 10 Machine Tool Dynamometers 371
10.1 Introduction . 371
10.2 Design Features of Dynamometers . 371
10.2.1 Rapier Parameters for Dynamometer Design . 372
10.2.2 Main Requirements of a Good Dynamometer 373
10.3 Dynamometers Based on Displacement Measurements . 374
10.3.1 Two-Channel Cantilever (Chisholm) Dynamometer 374
10.3.2 Two-Channel-Slotted Cantilever Dynamometer . 374
10.4 Dynamometers Based on Strain Measurement . 375
10.4.1 Strain Gauges and Wheatstone Bridges 375
10.4.2 Cantilever Strain Gauge Dynamometers 377
10.4.3 Octagonal Ring Dynamometers 378
10.4.3.1 Strain Rings and Octagonal Ring Transducers . 378
10.4.3.2 Turning Dynamometer 382
10.4.3.3 Surface Plunge-Cut Grinding Dynamometer .384
10.4.3.4 Milling Dynamometers .384
10.5 Piezoelectric (Quartz) Dynamometers 384
10.5.1 Principles and Features .384
10.5.2 Typical Piezoelectric Dynamometers .386
10.6 Review Questions 389
References 390
Chapter 11 Nontraditional Machine Tools and Operations 391
11.1 Introduction . 391
11.2 Classifcation of Nontraditional Machining Processes .392
11.3 Jet Machines and Operations 392
11.3.1 Abrasive Jet Machining .392
11.3.1.1 Process Characteristics and Applications .392
11.3.1.2 Work Station of Abrasive Jet Machining 395
11.3.1.3 Process Capabilities 396
11.3.2 Water Jet Machining (Hydrodynamic Machining) .397
11.3.2.1 Process Characteristics and Applications .397
11.3.2.2 Equipment of WJM .399
11.3.2.3 Process Capabilities 401
11.3.3 Abrasive Water Jet Machining .402
11.3.3.1 Process Characteristics and Applications .402
11.3.3.2 Abrasive Water Jet Machining Equipment .405
11.3.3.3 Process Capabilities 409
11.4 Ultrasonic Machining Equipment and Operation . 410
11.4.1 Defnitions, Characteristics, and Applications 410
11.4.2 USM Equipment . 413
11.4.2.1 Oscillating System and Magnetostriction Effect 413
11.4.2.2 Tool Feeding Mechanism 418
11.4.3 Design of Acoustic Horns 419
11.4.3.1 General Differential Equation . 419
11.4.3.2 Design of the Cylindrical Stepped Acoustic Horns (A(x) = C) 421
11.4.3.3 Design of Exponential Acoustic Horns (A(x) = A0e?2hx) 421xiv Contents
11.4.4 Process Capabilities 430
11.4.4.1 Stock Removal Rate 430
11.4.4.2 Accuracy and Surface Quality 432
11.4.5 Recent Developments 433
11.5 Chemical Machining . 434
11.5.1 Chemical Milling 435
11.5.2 Photochemical Machining (Spray Etching) 441
11.6 Electrochemical Machines and Operations 445
11.6.1 Process Characteristics and Applications 445
11.6.2 Elements of Electrochemical Machining 447
11.6.2.1 Tool 447
11.6.2.2 Workpiece .449
11.6.2.3 Electrolyte 449
11.6.3 ECM Equipment .449
11.6.4 Process Capabilities 451
11.7 Electrochemical Grinding Machines and Operations 453
11.8 Electrical Discharge Machines and Operations 454
11.8.1 Process Characteristics and Applications 454
11.8.2 ED Sinking Machine . 458
11.8.3 EDM-Spark Circuits (Power Supply Circuits) 460
11.8.3.1 Resistance-Capacitance Circuit .460
11.8.3.2 Transistorized Pulse Generator Circuits .462
11.8.4 EDM-Tool Electrodes 463
11.8.5 Process Capabilities 464
11.8.6 Electrical Discharge Milling .465
11.8.7 Electrodischarge Wire Cutting 468
11.9 Electron Beam Machining Equipment and Operations 470
11.9.1 Process Characteristics and Applications 470
11.9.2 Electron Beam Machining Equipment 471
11.9.3 Process Capabilities 474
11.10 Laser Beam Machining Equipment and Operations 475
11.10.1 Process Characteristics . 475
11.10.2 Types of Lasers 477
11.10.2.1 Pyrolithic and Photolithic Lasers . 477
11.10.2.2 Industrial Lasers . 477
11.10.2.3 Laser Beam Machining Operations . 478
11.10.3 LBM Equipment . 481
11.10.4 Applications and Capabilities .483
11.11 Plasma Arc Cutting Systems and Operations .485
11.11.1 Process Characteristics .485
11.11.2 Plasma Arc Cutting Systems 486
11.11.3 Applications and Capabilities of Plasma Arc Cutting 486
11.12 Review Questions 488
References 492
Chapter 12 Environment-Friendly Machine Tools and Operations 495
12.1 Introduction . 495
12.2 Traditional Machining 498
12.2.1 Cutting Fluids . 501
12.2.1.1 Classifcation of Cutting Fluids . 501Contents xv
12.2.1.2 Selection of Cutting Fluids 502
12.2.1.3 Evaluation of Cutting Fluids .502
12.2.2 Hazard Ranking of Cutting Fluids .503
12.2.3 Health Hazards of Cutting Fluids .504
12.2.4 Cryogenic Cooling 504
12.2.5 Ecological Machining .505
12.3 Nontraditional Machining Processes . 510
12.3.1 Chemical Machining 510
12.3.2 Electrochemical Machining 512
12.3.3 Electrodischarge Machining . 514
12.3.3.1 Protective Measures . 516
12.3.4 Laser Beam Machining 516
12.3.5 Ultrasonic Machining . 519
12.3.5.1 Electromagnetic Field 520
12.3.5.2 Ultrasonic Waves . 520
12.3.5.3 Abrasives Slurry 520
12.3.5.4 Contact Hazards 521
12.3.5.5 Other Hazards 521
12.3.6 Abrasive Jet Machining 521
12.4 Review Questions . 523
References 524
Chapter 13 Design for Machining . 525
13.1 Introduction 525
13.1.1 General Design Rules . 525
13.2 General Design Recommendations 526
13.3 Design for Machining by Cutting . 528
13.3.1 Turning . 528
13.3.1.1 Economic Production Quantities . 529
13.3.1.2 Design Recommendations for Turning 530
13.3.1.3 Dimensional Control . 535
13.3.2 Drilling and Allied Operations . 535
13.3.2.1 Economic Production Quantities . 536
13.3.2.2 Design Recommendations for Drilling and Allied Operations . 536
13.3.2.3 Dimensional Control . 539
13.3.3 Milling 539
13.3.3.1 Design Recommendations . 539
13.3.3.2 Dimensional Factors and Tolerances . 542
13.3.4 Shaping, Planing, and Slotting 542
13.3.4.1 Design Recommendations . 542
13.3.4.2 Dimensional Control . 543
13.3.5 Broaching 544
13.3.5.1 Design Recommendations .544
13.3.5.2 Dimensional Factors 549
13.3.5.3 Recommended Tolerances . 550
13.3.6 Thread Cutting 550
13.3.6.1 Design Recommendations . 550
13.3.6.2 Dimensional Factors and Tolerances . 551
13.3.7 Gear Cutting . 552
13.3.7.1 Design Recommendations . 552
13.3.7.2 Dimensional Factors 554xvi Contents
13.4 Design for Grinding . 554
13.4.1 Surface Grinding 554
13.4.1.1 Design Recommendations . 554
13.4.1.2 Dimensional Control . 556
13.4.2 Cylindrical Grinding 556
13.4.2.1 Design Recommendations . 556
13.4.2.2 Dimensional Factors 557
13.4.3 Centerless Grinding 557
13.4.3.1 Design Recommendations . 558
13.4.3.2 Dimensional Control . 559
13.5 Design for Finishing Processes 559
13.5.1 Honing 559
13.5.2 Lapping .560
13.5.3 Superfnishing . 561
13.6 Design for Chemical and Electrochemical Machining . 561
13.6.1 Chemical Machining 561
13.6.1.1 Design Recommendations . 561
13.6.1.2 Dimensional Factors and Tolerances . 563
13.6.2 Electrochemical Machining 563
13.6.2.1 Design Recommendations .564
13.6.2.2 Dimensional Factors 566
13.6.3 Electrochemical Grinding 566
13.6.3.1 Design Recommendations .566
13.6.3.2 Dimensional Factors 567
13.7 Design for Thermal Machining . 567
13.7.1 Electrodischarge Machining . 567
13.7.1.1 Design Recommendations . 567
13.7.1.2 Dimensional Factors 568
13.7.2 Electron Beam Machining 568
13.7.3 Laser Beam Machining 569
13.8 Design for Ultrasonic Machining 570
13.9 Design for Abrasive Jet Machining . 571
13.10 Review Questions . 572
References 573
Chapter 14 Accuracy and Surface Integrity Realized by Machining Processes 575
14.1 Introduction 575
14.2 Surface Texture 575
14.3 Surface Quality and Functional Properties . 577
14.4 Surface Integrity 579
14.5 Surface Effects by Traditional Machining . 582
14.5.1 Chip Removal Processes . 582
14.5.2 Grinding 583
14.6 Surface Effects by Nontraditional Machining . 587
14.6.1 Electrochemical and Chemical Machining .590
14.6.2 Thermal Nontraditional Processes . 591
14.6.2.1 Electrodischarge Machining . 591
14.6.2.2 Laser Beam Machining .596
14.6.2.3 Electron Beam Machining 597
14.6.2.4 Plasma Beam Machining (PBM) . 598Contents xvii
14.6.2.5 Electroerosion Dissolution Machining 598
14.6.2.6 Electrochemical Discharge Grinding 598
14.6.3 Mechanical Nontraditional Processes 599
14.7 Reducing Distortion and Surface Effects in Machining 599
14.8 Review Questions . 601
References 601
Chapter 15 Automated Manufacturing System .603
15.1 Introduction 603
15.2 Manufacturing Systems .605
15.3 Flexible Automation-Flexible Manufacturing Systems .609
15.3.1 Elements of Flexible Manufacturing System . 610
15.3.2 Limitations of Flexible Manufacturing System 611
15.3.3 Features and Characteristics . 611
15.3.4 New Developments in Flexible Manufacturing System Technology . 611
15.4 Computer Integrated Manufacturing . 612
15.4.1 Computer-Aided Design . 615
15.4.2 Computer-Aided Process Planning . 616
15.4.3 Computer-Aided Manufacturing 617
15.5 Lean Production–Just-in-Time Manufacturing Systems . 617
15.5.1 Steps for Implementing the IMPS Lean Production 618
15.5.2 Just-in-Time and Just-in-Case Production 619
15.6 Adaptive Control 620
15.7 Smart Manufacturing and Artifcial Intelligence 622
15.7.1 Expert Systems . 622
15.7.2 Machine Vision . 623
15.7.3 Artifcial Neural Networks . 623
15.7.4 Natural-Language Systems .624
15.7.5 Fuzzy Logic (Fuzzy Models) 624
15.8 Factory of the Future .624
15.9 Concluding Remarks Related to Automated Manufacturing 625
15.10 Review Questions .625
References 626
Index .
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