Machine Design with CAD and Optimization

SAYED M. METWALLI, is Professor Emeritus of Machine Design and past Chair of Mechanical Design and Production Department, Cairo University, Egypt. He received a BS (Mech. Eng.) with honor from Cairo University (1965) and MS and PhD (Mech. Eng.) from State University of New York at Buffalo, USA, (1970) and (1973) respectively. Metwalli has conducted research and taught at North Carolina State University, the University of Central Florida, USA, and Kuwait University, and holds a US patent. His research interests are in design optimization theory, developing algorithms, and CAD/CAM software, with particular emphasis on optimum synthesis of mechanical components and systems including dynamics and controls for multitude of applications. He has conducted sponsored research with DOD/NRL, UNESCO, IBM-UK, NSF, EPA, USAID, and CU and has published more than 150 papers in journals and peer reviewed international conferences. His work with various manufacturers successfully implemented CAD and design optimization in their product design and development. He is an ASME Life Fellow, registered mechanical design consultant, and has been a registered PE in Florida.

Preface xxiii

Acknowledgments xxvii

About the Companion Website xxix

Part I Introduction and Design Considerations 1

1 Introduction to Design 3

1.1 Introduction 6

1.2 Phases of Design 8

1.3 Basic Mechanical Functions 9

1.4 Design Factors 11

1.5 Synthesis Approach to Design 12

1.6 Product Life Cycle 13

1.7 Business Measures 14

1.8 Research and Development Process in Product Cycle 15

1.9 Teamwork for Product or System Design 16

1.10 Design and Development Case Study 16

1.11 Units and Fundamentals 16

1.12 Summary 26

2 Design Considerations 31

2.1 Mathematical Modeling 34

2.2 Calculation Tools 57

2.3 Design Procedure 60

2.4 Manufacturing Processes 62

2.5 Standard Sets and Components 72

2.6 Codes and Standards 72

2.7 Summary 73

Part II Knowledge-Based Design 79

3 Introduction to Computer-Aided Techniques 81

3.1 CAD and Geometric Modeling 82

3.2 Geometric Construction and FE Analysis 84

3.3 CAD/CAM/CAE and Advanced Systems 85

3.4 Virtual Reality 87

3.5 Summary 89

4 Computer-Aided Design 91

4.1 3D Geometric Modeling and Viewing Transformation 95

4.2 Parametric Modeling 111

4.3 CAD Hardware and Software 135

4.4 Rendering and Animation 135

4.5 Data Structure 146

4.6 Using CAD in 3D Modeling and CAM 149

4.7 Summary 149

5 Optimization 155

5.1 Introduction 158

5.2 Searches in One Direction 167

5.3 Multidimensional: Classical Indirect Approach 173

5.4 Multidimensional Unconstrained Problem 179

5.5 Multidimensional Constrained Problem 200

5.6 Applications to Machine Elements and Systems 209

5.7 Summary 213

6 Stresses, Deformations, and Deflections 221

6.1 Loads, Shear, Moment, Slope, and Deflection 227

6.2 Mathematical Model 253

6.3 Simple Stresses, Strains, and Deformations 254

6.4 Combined Stresses 264

6.5 Curved Beams 279

6.6 Strain Energy and Deflection 283

6.7 Columns 288

6.8 Equivalent Element 296

6.9 Thermal Effects 297

6.10 Stress Concentration Factors 300

6.11 Finite Element Method 302

6.12 Computer-Aided Design and Optimization 323

6.13 Summary 333

7 Materials Static and Dynamic Strength3 43

7.1 Material Structure and Failure Modes 348

7.2 Numbering Systems and Designations 358

7.3 Heat Treatment and Alloying Elements 362

7.4 Material Propertied and General Applications 366

7.5 Particular Materials for Machine Elements 381

7.6 Hardness and Strength 383

7.7 Failure and Static Failure Theories 385

7.8 Fatigue Strength and Factors Affecting Fatigue 397

7.9 Fracture Mechanics and Fracture Toughness 413

7.10 Computer-Aided Selection and Optimization 419

7.10.1 Material Properties: Carbon Steel 419

7.11 Summary 428

8 Introduction to Elements and System Synthesis 439

8.1 Introduction 441

8.2 Basic and Common Machine Elements 442

8.3 Reverse Engineering 469

8.4 Sample Applications 470

8.5 Computer-Aided Design 476

8.6 System Synthesis 479

8.7 Computer-Aided Assembly 480

8.8 Summary 480

Part III Detailed Design of Machine Elements 487

Section A Basic Joints and Machine Elements 489

9 Screws, Fasteners, and Permanent Joints 491

9.1 Standards and Types 494

9.2 Stresses in Threads 497

9.3 Bolted Connections 498

9.4 Bolt Strength in Static and Fatigue 507

9.5 Power Screws 511

9.6 Permanent Joints 518

9.7 Computer-Aided Design and Optimization 527

9.8 Summary 532

10 Springs 539

10.1 Types of Springs 542

10.2 Helical Springs 542

10.3 Leaf Springs 567

10.4 Belleville Springs 574

10.5 Elastomeric and Other Springs 576

10.6 Computer-Aided Design and Optimization 576

10.7 Summary 579

11 Rolling Bearings 585

11.1 Bearing Types and Selection 588

11.2 Standard Dimension Series 590

11.3 Initial Design and Selection 592

11.4 Bearing Load 595

11.5 Detailed Design and Selection 601

11.6 Speed Limits 609

11.7 Lubrication and Friction 609

11.8 Mounting and Constructional Details 610

11.9 Computer-Aided Design and Optimization 611

11.10 Summary 617

12 Journal Bearings 621

12.1 Lubricants 624

12.2 Hydrodynamic Lubrication 629

12.3 Journal Bearing Design Procedure 641

12.4 Boundary and Mixed Lubrication 646

12.5 Plain Bearing Materials 648

12.6 CAD and Optimization 653

12.7 Summary 661

Section B Power Transmitting and Controlling Elements 667

13 Introduction to Power Transmission and Control 669

13.1 Prime Movers and Machines 671

13.2 Collinear and Noncollinear Transmission Elements 671

13.3 Power Control Elements 675

13.4 Computer-Aided Design of a Power Transmission System 676

13.5 Summary 681

14 Spur Gears 683

14.1 Types and Utility 687

14.2 Definitions, Kinematics, and Standards 688

14.3 Force Analysis and Power Transmission 699

14.4 Design Procedure 701

14.5 Critical Speed 732

14.6 CAD and Optimization 734

14.7 Constructional Details 742

14.8 Summary 747

15 Helical, Bevel, and Worm Gears 755

15.1 Helical Gears 758

15.2 Bevel Gears 776

15.3 Worm Gears 781

15.4 Gear Failure Regimes and Remedies 787

15.5 Computer-Aided Design and Optimization 787

15.6 Constructional Details 794

15.7 Summary 795

16 Flexible Elements 801

16.1 V-belts 804

16.2 Flat Belts 818

16.3 Ropes 823

16.4 Chains 831

16.5 Friction Drives 839

16.6 Flexible Shafts 839

16.7 Computer-Aided Design and Optimization 840

16.8 Summary 849

17 Shafts 857

17.1 Types of Shafts and Axles 859

17.2 Mathematical Model 860

17.3 Initial Design Estimate 865

17.4 Detailed Design 867

17.5 Design for Rigidity 871

17.6 Critical Speed 872

17.7 Computer-Aided Design and Optimization 873

17.8 Constructional Details 879

17.9 Summary 880

18 Clutches, Brakes, and Flywheels 887

18.1 Classifications of Clutches and Brakes 889

18.2 Cone Clutches and Brakes 889

18.3 Disk Clutches and Brakes 891

18.4 Caliper Disk Brakes 898

18.5 Energy Dissipation and Temperature Rise 899

18.6 Design Process 901

18.7 Computer-Aided Design and Optimization 902

18.8 Flywheels 904

18.9 Constructional Details 907

18.10 Summary 908

Problems 908

References 911

Internet Links 912 

Appendix A Figures and Tables 913

A.1 Conversion Between US and SI Units 913

A.2 Standard SI Prefixes 914

A.3 Preferred Numbers and Sizes 915

A.4 Standard Rods, or Bars 916

A.5 Standard Joining and Retaining Elements 917

A.6 Standard Sealing Elements 920

A.7 Material Properties 922

A.8 Standard Sections or Profiles and Section Properties 931

Index 949