1 Introduction 1
1-1 Design 2
1-2 Mechanical Engineering Design 4
1-3 Interaction between Design Process Elements 9
1-4 Design Tools and Resources 12
1-5 The Design Engineer’s Professional Responsibilities 14
1-6 Codes and Standards 16
1-7 Economics 18
1-8 Safety and Product Liability 20
1-9 The Adequacy Assessment 20
1-10 Uncertainty 22
1-11 Stress and Strength 23
1-12 Design Factor and Factor of Safety 27
1-13 Reliability 28
1-14 Units and Preferred Units 29
1-15 Calculations and Significant Figures 32
Problems 33
2 Failture Resulting from Static Loading 39
2-1 Static Strength 45
2-2 Stress Concentration 45
2-3 Failure Theories 47
2-4 Maximum-Shear-Stress Theory for Ductile Materials 49
2-5 Distortion-Energy Theory for Ductile Materials 50
2-6 Coulomb-Mohr Theory for Ductile Materials 56
2-7 Failure of Ductile Materials Summary 59
2-8 Maximum-Normal-Stress Theory for Brittle Materials 63
2-9 Modifications of the Mohr Theory for Brittle Materials 64
2-10 Failure of Brittle Materials Summary 67
2-11 Selection of Failure Criteria 68
2-12 Static or Quasi-Static Loading on a Shaft 68
2-13 Introduction to Fracture Mechanics 71
2-14 Stochastic Analysis 81
Problems 88
3 Fatigue Failture Resulting from Variable Loading 97
3-1 Introduction to Fatigue in Metals 98
3-2 Approach to Fatigue Failure in Analysis and Design 104
3-3 Fatigue-Life Methods 106
3-4 The Stress-Life Method 106
3-5 The Strain-Life Method 109
3-6 The Linear-Elastic Fracture Mechanics Method 113
3-7 The Endurance Limit 117
3-8 Fatigue Strength 119
3-9 Endurance Limit Modifying Factors 122
3-10 Stress Concentration and Notch Sensitivity 130
3-11 Characterizing Fluctuating Stresses 139
3-12 Fatigue Failure Criteria for Fluctuating Stress 142
3-13 Torsional Fatigue Strength under Fluctuating Stresses 158
3-14 Combinations of Loading Modes 159
3-15 Varying，Fluctuating Stresses； Cumulative Fatigue Damage 162
3-16 Surface Fatigue Strength 169
3-17 Stochastic Analysis 172
Problems 188
4 Flexible Mechanical Elements 197
4-1 Belts 198
4-2 Flat-and Round-Belt Drives 202
4-3 V Belts 219
4-4 Timing Belts 228
4-5 Roller Chain 229
4-6 Wire Rope 238
4-7 Flexible Shafts 247
Problems 248
5 Gears—Force Analysis 257
5-1 Force Analysis—Spur Gearing 258
5-2 Force Analysis—Bevel Gearing 261
5-3 Force Analysis—Helical Gearing 264
5-4 Force Analysis—Worm Gearing 266
Problems 272
6 Spur and Helical Gears 280
6-1 The Lewis Bending Equation 284
6-2 Surface Durability 292
6-3 AGMA Stress Equations 294
6-4 AGMA Strength Equations 296
6-5 Geometry Factors I and J （ZI and YJ） 301
6-6 The Elastic Coefficient Cp （ZE） 306
6-7 Dynamic Factor Kv 306
6-8 Overload Factor Ko 308
6-9 Surface Condition Factor Cf （ZR） 308
6-10 Size Factor Ks 309
6-11 Load-Distribution Factor Km （KH） 309
6-12 Hardness-Ratio Factor CH 311
6-13 Stress Cycle Life Factors YN and ZN 312
6-14 Reliability Factor KR （ Yz ） 313
6-15 Temperature Factor KT （ Yθ） 314
6-16 Rim-Thickness Factor KB 314
6-17 Safety Factors SF and SH 315
6-18 Analysis 318
6-19 Design of a Gear Mesh 327
Problems 332
7 Bevel and Worm Gears 338
7-1 Bevel Gearing-General 339
7-2 Bevel-Gear Stresses and Strengths 341
7-3 AGMA Equation Factors 346
7-4 Straight-Bevel Gear Analysis 358
7-5 Design of a Straight-Bevel Gear Mesh 361
7-6 Worm Gearing—AGMA Equation 365
7-7 Worm-Gear Analysis 368
7-8 Designing a Worm-Gear Mesh 373
7-9 Buckingham Wear Load 377
Problems 378
8 Lubrication and Journal Bearings 383
8-1 Types of Lubrication 384
8-2 Viscosity 385
8-3 Petroff’s Equation 388
8-4 Stable Lubrication 389
8-5 Thick-Film Lubrication 390
8-6 Hydrodynamic Theory 392
8-7 Design Considerations 396
8-8 The Relations of the Variables 399
8-9 Steady-State Conditions in Self-Contained Bearings 412
8-10 Clearance 416
8-11 Pressure-Fed Bearings 418
8-12 Loads and Materials 425
8-13 Bearing Types 427
8-14 Thrust Bearings 428
8-15 Boundary-Lubricated Bearings 429
Problems 440
9 Rolling-Contact Bearings 445
9-1 Bearing Types 447
9-2 Bearing Life 450
9-3 Bearing Load Life at Rated Reliability 450
9-4 Bearing Survival：Reliability versus Life 452
9-5 Relating Load，Life，and Reliability 454
9-6 Combined Radial and Thrust Loading 455
9-7 Variable Loading 462
9-8 Selection of Ball and Cylindrical Roller Bearings 466
9-9 Selection of Tapered Roller Bearings 469
9-10 Design Assessment for Selected Rolling-Contact Bearings 481
9-11 Lubrication 486
9-12 Mounting and Enclosure 487
Problems 491
10 Shafts and Axles 498
10-1 Introduction 499
10-2 Geometric Constraints 504
10-3 Strength Constraints 510
10-4 Strength Constraints—Additional Methods 518
10-5 Shaft Materials 521
10-6 Hollow Shafts 522
10-7 Critical Speeds 522
10-8 Shaft Design 529
Problems 530
11 Screws，Fasteners，and the Design of Nonpermanent Joints 540
11-1 Thread Standards and Definitions 541
11-2 The Mechanics of Power Screws 545
11-3 Threaded Fasteners 554
11-4 Joints—Fastener Stiffness 557
11-5 Joints—Member Stiffness 559
11-6 Bolt Strength 563
11-7 Tension Joints—The External Load 568
11-8 Relating Bolt Torque to Bolt Tension 569
11-9 Statically Loaded Tension Joint with Preload 573
11-10 Gasketed Joints 577
11-11 Fatigue Loading of Tension Joints 577
11-12 Shear Joints 584
11-13 Setscrews 590
11-14 Keys and Pins 592
11-15 Stochastic Considerations 600
Problems 601
12 Clutches，Brakes，Couplings，and Flywheels 618
12-1 Static Analysis of Clutches and Brakes 620
12-2 Internal Expanding Rim Clutches and Brakes 625
12-3 External Contracting Rim Clutches and Brakes 635
12-4 Band-Type Clutches and Brakes 639
12-5 Frictional-Contact Axial Clutches 640
12-6 Disk Brakes 644
12-7 Cone Clutches and Brakes 649
12-8 Energy Considerations 651
12-9 Temperature Rise 653
12-10 Friction Materials 657
12-11 Miscellaneous Clutches and Couplings 660
12-12 Flywheels 662
Problems 668
13 Mechanical Springs 677
13-1 Stresses in Helical Springs 678
13-2 The Curvature Effect 679
13-3 Deflection of Helical Springs 680
13-4 Compression Springs 681
13-5 Stability 682
13-6 Spring Materials 683
13-7 Helical Compression Spring Design for Static Service 689
13-8 Critical Frequency of Helical Springs 696
13-9 Fatigue Loading of Helical Compression Springs 698
13-10 Helical Compression Spring Design for Fatigue Loading 702
13-11 Extension Springs 705
13-12 Helical Coil Torsion Springs 714
13-13 Belleville Springs 721
13-14 Miscellaneous Springs 722
13-15 Summary 724
Problems 725
Appendix A Useful Tables 732
Appendix B Answers to Selected Problems 789