Life Cycle Reliability Engineering

1 Reliability Engineering and Product Life Cycle 1

1.1 Reliability Engineering 1

1.2 Product Life Cycle 2

1.3 Integration of Reliability Engineering into the Product Life Cycle 5

1.4 Reliability in the Concurrent Product Realization Process 6

Problems 7

2 Reliability Definition Metrics and Product Life Distributions 9

2.1 Introduction 9

2.2 Reliability Definition 10

2.3 Reliability Metrics 12

2.4 Exponential Distribution 17

2.5 Weibull Distribution 19

2.6 Mixed Weibull Distribution 22

2.7 Smallest Extreme Value Distribution 24

2.8 Normal Distribution 26

2.9 Lognormal Distribution 28

Problems 31

3 Reliability Planning and Specification 33

3.1 Introduction 33

3.2 Customer Expectations and Satisfaction 34

3.3 Reliability Requirements 41

3.4 Reliability Program Development 48

3.5 Reliability Design and Design for Six Sigma 61

Problems 64

4 System Reliability Evaluation and Allocation 65

4.1 Introduction 65

4.2 Reliability Block Diagram 66

4.3 Series Systems 68

4.4 Parallel Systems 71

4.5 Mixed Configurations 73

4.6 k-out-of-n Systems 77

4.7 Redundant Systems 79

4.8 Reliability Evaluation of Complex Systems 84

4.9 Confidence Intervals for System Reliability 91

4.10 Measures of Component Importance 99

4.11 Reliability Allocation 106

Problems 118

5 Reliability Improvement Through Robust Design 122

5.1 Introduction 122

5.2 Reliability and Robustness 123

5.3 Reliability Degradation and Quality Loss 125

5.4 Robust Design Process 129

5.5 Boundary Definition and Interaction Analysis 132

5.6 P-Diagram 133

5.7 Noise Effects Management 134

5.8 Design of Experiments 136

5.9 Experimental Life Data Analysis 148

5.10 Experimental Degradation Data Analysis 152

5.11 Design Optimization 156

5.12 Robust Reliability Design of Diagnostic Systems 172

5.13 Case Study 179

5.14 Advanced Topics in Robust Design 181

Problems 190

6 Potential Failure Mode Avoidance 194

6.1 Introduction 194

6.2 Failure Mode and Effects Analysis 195

6.3 Advanced Topics in FMEA 208

6.4 Fault Tree Analysis 212

6.5 Advanced Topics in FTA 225

6.6 Computer-Aided Design Controls 230

Problems 235

7 Accelerated Life Tests 237

7.1 Introduction 237

7.2 Development of Test Plans 238

7.3 Common Stresses and Their Effects 246

7.4 Life–Stress Relationships 252

7.5 Graphical Reliability Estimation at Individual Test Conditions 266

7.6 Analytical Reliability Estimation at Individual Test Conditions 274

7.7 Reliability Estimation at Use Condition 292

7.8 Compromise Test Plans 302

7.9 Highly Accelerated Life Tests 326

Problems 327

8 Degradation Testing and Analysis 332

8.1 Introduction 332

8.2 Determination of the Critical Performance Characteristic 333

8.3 Reliability Estimation from Pseudo life 334

8.4 Degradation Analysis with Random-Effect Models 337

8.5 Degradation Analysis for Destructive Inspections 345

8.6 Stress-Accelerated Degradation Tests 351

8.7 Accelerated Degradation Tests with Tightened Thresholds 358

8.8 Accelerated Degradation Test Planning 364

Problems 373

9 Reliability Verification Testing 379

9.1 Introduction 379

9.2 Planning Reliability Verification Tests 380

9.3 Bogey Testing 383

9.4 Sample Size Reduction by Tail Testing 389

9.5 Sequential Life Testing 394

9.6 Reliability Verification Using Prior Information 406

9.7 Reliability Verification Through Degradation Testing 408

Problems 410

10 Stress Screening 412

10.1 Introduction 412

10.2 Screening Techniques 413

10.3 Design of Screen Plans 415

10.4 Principle of Degradation Screening 417

10.5 Part-Level Degradation Screening 419

10.6 Module-Level Screening 425

10.7 Module Reliability Modeling 431

10.8 Cost Modeling 433

10.9 Optimal Screen Plans 435

Problems 438

11 Warranty Analysis 442

11.1 Introduction 442

11.2 Warranty Policies 443

11.3 Warranty Data Mining 447

11.4 Reliability Estimation from Warranty Claim Times 451

11.5 Two-Dimensional Reliability Estimation 454

11.6 Warranty Repair Modeling 470

11.7 Warranty Cost Estimation 473

11.8 Field Failure Monitoring 477

11.9 Warranty Cost Reduction 480

Problems 482

Appendix: Orthogonal Arrays Linear Graphs and Interaction Tables 486

References 495

Index 511