Reliability, Maintainability And Risk - Practical Methods For Engineers

Contents......Page 5
Preface......Page 11
Acknowledgements......Page 13
Part One Understanding Reliability Parameters and Costs......Page 15
1.1 FAILURE DATA......Page 17
1.2 HAZARDOUS FAILURES......Page 18
1.3 RELIABILITY AND RISK PREDICTION......Page 19
1.4 ACHIEVING RELIABILITY AND SAFETY-INTEGRITY......Page 20
1.5 THE RAMS-CYCLE......Page 21
1.6 CONTRACTUAL PRESSURES......Page 23
2.1 DEFINING FAILURE AND FAILURE MODES......Page 25
2.2 FAILURE RATE AND MEAN TIME BETWEEN FAILURES......Page 26
2.3 INTERRELATIONSHIPS OF TERMS......Page 28
2.4 THE BATHTUB DISTRIBUTION......Page 30
2.5 DOWN TIME AND REPAIR TIME......Page 31
2.7 HAZARD AND RISK-RELATED TERMS......Page 34
2.8 CHOOSING THE APPROPRIATE PARAMETER......Page 35
EXERCISES......Page 36
3.1 THE COST OF QUALITY......Page 37
3.2 RELIABILITY AND COST......Page 40
3.3 COSTS AND SAFETY......Page 43
Part Two Interpreting Failure Rates......Page 47
4.1 DATA ACCURACY......Page 49
4.2 SOURCES OF DATA......Page 51
4.3 DATA RANGES......Page 55
4.4 CONFIDENCE LIMITS OF PREDICTION......Page 58
4.5 OVERALL CONCLUSIONS......Page 60
5.2 INFERENCE AND CONFIDENCE LEVELS......Page 61
5.3 THE CHI-SQUARE TEST......Page 63
5.4 DOUBLE-SIDED CONFIDENCE LIMITS......Page 64
5.5 SUMMARIZING THE CHI-SQUARE TEST......Page 65
5.6 RELIABILITY DEMONSTRATION......Page 66
5.7 SEQUENTIAL TESTING......Page 70
EXERCISES......Page 71
6.1 THE WEIBULL DISTRIBUTION......Page 72
6.2 USING THE WEIBULL METHOD......Page 74
6.3 MORE COMPLEX CASES OF THE WEIBULL DISTRIBUTION......Page 81
6.4 CONTINUOUS PROCESSES......Page 82
EXERCISES......Page 83
Part Three Predicting Reliability and Risk......Page 85
7.2 PROBABILITY THEORY......Page 87
7.3 RELIABILITY OF SERIES SYSTEMS......Page 90
7.4 REDUNDANCY RULES......Page 91
7.5 GENERAL FEATURES OF REDUNDANCY......Page 97
EXERCISES......Page 100
8.1 BLOCK DIAGRAM AND MARKOV ANALYSIS......Page 101
8.2 COMMON CAUSE (DEPENDENT) FAILURE......Page 112
8.3 FAULT TREE ANALYSIS......Page 117
8.4 EVENT TREE DIAGRAMS......Page 124
9.1 THE RELIABILITY PREDICTION METHOD......Page 128
9.2 ALLOWING FOR DIAGNOSTIC INTERVALS......Page 129
9.3 FMEA (FAILURE MODE AND EFFECT ANALYSIS)......Page 131
9.4 HUMAN FACTORS......Page 132
9.5 SIMULATION......Page 137
9.6 COMPARING PREDICTIONS WITH TARGETS......Page 140
EXERCISES......Page 141
10.1 FREQUENCY AND CONSEQUENCE......Page 142
10.2 PERCEPTION OF RISK AND ALARP......Page 143
10.3 HAZARD IDENTIFICATION......Page 144
10.4 FACTORS TO QUANTIFY......Page 149
Part Four Achieving Reliability and Maintainability......Page 154
11.1 SPECIFYING AND ALLOCATING THE REQUIREMENT......Page 156
11.2 STRESS ANALYSIS......Page 158
11.4 FAILURE MECHANISMS......Page 161
11.5 COMPLEXITY AND PARTS......Page 163
11.6 BURN-IN AND SCREENING......Page 166
11.7 MAINTENANCE STRATEGIES......Page 167
12.1 REVIEW TECHNIQUES......Page 168
12.2 CATEGORIES OF TESTING......Page 169
12.3 RELIABILITY GROWTH MODELLING......Page 173
EXERCISES......Page 176
13.2 INFORMATION AND DIFFICULTIES......Page 177
13.3 TIMES TO FAILURE......Page 178
13.4 SPREADSHEETS AND DATABASES......Page 179
13.5 BEST PRACTICE AND RECOMMENDATIONS......Page 181
13.6 ANALYSIS AND PRESENTATION OF RESULTS......Page 182
13.7 EXAMPLES OF FAILURE REPORT FORMS......Page 183
14.1 KEY DESIGN AREAS......Page 186
14.2 MAINTENANCE STRATEGIES AND HANDBOOKS......Page 193
15.1 PREDICTION METHODS......Page 206
15.2 DEMONSTRATION PLANS......Page 214
16.1 WHAT IS QRCM?......Page 218
16.2 THE QRCM DECISION PROCESS......Page 219
16.3 OPTIMUM REPLACEMENT (DISCARD)......Page 220
16.4 OPTIMUM SPARES......Page 222
16.4 OPTIMUM PROOF-TEST......Page 223
16.6 CONDITION MONITORING......Page 224
17.1 PROGRAMMABLE DEVICES......Page 226
17.2 SOFTWARE FAILURES......Page 227
17.3 SOFTWARE FAILURE MODELLING......Page 228
17.4 SOFTWARE QUALITY ASSURANCE......Page 230
17.5 MODERN/FORMAL METHODS......Page 236
17.6 SOFTWARE CHECKLISTS......Page 239
Part Five Legal, Management and Safety Considerations......Page 244
18.1 SETTING OBJECTIVES AND SPECIFICATIONS......Page 246
18.3 PROGRAMME ACTIVITIES......Page 247
18.5 STANDARDS AND GUIDANCE DOCUMENTS......Page 250
19.1 ESSENTIAL AREAS......Page 251
19.2 OTHER AREAS......Page 254
19.3 PITFALLS......Page 255
19.4 PENALTIES......Page 257
19.5 SUBCONTRACTED RELIABILITY ASSESSMENTS......Page 259
19.6 EXAMPLE......Page 260
20.1 THE GENERAL SITUATION......Page 261
20.2 STRICT LIABILITY......Page 262
20.3 THE CONSUMER PROTECTION ACT 1987......Page 263
20.4 HEALTH AND SAFETY AT WORK ACT 1974......Page 264
20.5 INSURANCE AND PRODUCT RECALL......Page 265
21.1 HISTORY OF MAJOR INCIDENTS......Page 267
21.2 DEVELOPMENT OF MAJOR INCIDENT LEGISLATION......Page 268
21.3 CIMAH SAFETY REPORTS......Page 269
21.4 OFFSHORE SAFETY CASES......Page 272
21.5 PROBLEM AREAS......Page 274
21.6 THE COMAH DIRECTIVE (1999)......Page 275
22.1 SAFETY-RELATED OR SAFETY-CRITICAL?......Page 276
22.2 SAFETY-INTEGRITY LEVELS (SILs)......Page 277
22.3 PROGRAMMABLE ELECTRONIC SYSTEMS (PESs)......Page 279
22.4 CURRENT GUIDANCE......Page 281
22.5 ACCREDITATION AND CONFORMITY OF ASSESSMENT......Page 285
23.2 THE DATAMET CONCEPT......Page 286
23.3 FORMATION OF THE PROJECT GROUP......Page 290
23.4 RELIABILITY REQUIREMENTS......Page 291
23.5 FIRST DESIGN REVIEW......Page 292
23.6 DESIGN AND DEVELOPMENT......Page 294
23.8 HINTS......Page 295
A1 TERMS RELATED TO FAILURE......Page 296
A2 RELIABILITY TERMS......Page 298
A3 MAINTAINABILITY TERMS......Page 299
A4 TERMS ASSOCIATED WITH SOFTWARE......Page 300
A5 TERMS RELATED TO SAFETY......Page 302
A6 MISCELLANEOUS TERMS......Page 303
Appendix 2 Percentage points of the Chi- square distribution......Page 305
Appendix 3 Microelectronics failure rates......Page 309
Appendix 4 General failure rates......Page 311
Appendix 5 Failure mode percentages......Page 318
Appendix 6 Human error rates......Page 321
Appendix 7 Fatality rates......Page 323
Appendix 8 Answers to exercises......Page 325
OTHER PUBLICATIONS......Page 330
STANDARDS AND GUIDELINES......Page 331
JOURNALS......Page 332
1 CHECKLIST AND SCORING FOR EQUIPMENT CONTAINING PROGRAMMABLE ELECTRONICS......Page 333
2 CHECKLIST AND SCORING FOR NON-PROGRAMMABLE EQUIPMENT......Page 337
POTENTIAL CONSEQUENCES......Page 340
Appendix 12 HAZID checklist......Page 343
Index......Page 346