AS 3960-1990

1 - AS 3960:1990 GUIDE TO RELIABILITY AND MAINTAINABILITY PROGRAM MANAGEMENT
4 - PREFACE
5 - CONTENTS
6 - FOREWORD
8 - SECTION 1 - SCOPE AND GENERAL
8 - 1.1 SCOPE.
8 - 1.2 REFERENCED DOCUMENTS.
8 - 1.3 DEFINITIONS.
9 - SECTION 2 - RELIABILITY AND MAINTAINABILITY PROGRAM
9 - 2.1 GENERAL.
9 - 2.1.1 Life cycle concept.
9 - 2.1.2 Aim of a reliability and maintainability
9 - program.
9 - 2.1.3 General considerations on maintainabi lity.
9 - 2.1.4 Cost considerations.
10 - 2.1.5 Relative effectiveness of program activities.
10 - TABLE 1
10 - RELIABILITY AND MAINTAINABILITY PROGRAM ACTIVITIES DURING THE PRINCIPAL PHASES OF A PROJECT
13 - 2.1.6 Training.
13 - 2.2 PROGRAM ACTIVITIES.
13 - 2.2.1 Definition phase.
13 - 2.2.1. 1
13 - 2.2.1. 2
13 - 2.2.2 Design and development phase.
13 - 2.2.2. 1
13 - 2.2.2. 2
13 - 2.2.2. 3
16 - 2.2.2.4
16 - 2.2.2.5
18 - 2.2.2.6
18 - 2.2.3 Production phase.
18 - 2.2.3.1
18 - 2.2.3.2
18 - 2.2.3.3
18 - 2.2.3.4
19 - 2.2.3.5
19 - 2.2.3. 6
19 - 2.2.4 Installation and commissioning phase.
19 - 2.2.4. 1
19 - 2.2.4. 2
19 - 2.2.4. 3
19 - 2.2.4.4
19 - 2.2.4. 5
19 - 2.2.4. 6
19 - 2.2.5 Operation- usage and maintenance phase.
19 - 2.2.5. 1
20 - 2.2.5. 2
21 - SECTION 3 - SPECIFICATION OF RELIABILITY AND MAINTAINABILITY
21 - 3.1 GENERAL.
21 - 3.1.1 Types of specification.
21 - 3.1.2 Purpose of reliability and maintainabi lity
21 - clauses.
21 - 3.1.3 Qualitative versus quantitative approach to
21 - reliability and maintainabi lity.
21 - 3.1.4 Quantitative reliability clauses.
23 - 3.1.5 Problems in applying the quantitative
23 - approach.
23 - 3.1.6 Qualitative approach.
23 - 3.1.7 Quantitative maintainability clauses.
23 - 3.1.8 Qualitative maintainabi lity requirements.
24 - 3.2 WRITING RELIABILITY AND MAINTAIN-ABILITY CLAUSES IN A SPECIFICATION.
24 - 3.2.1 Necessary clauses.
24 - 3.2.1. 1
24 - 3.2.1. 2
24 - 3.2.2 Function of an item.
24 - 3.2.3 Criteria for failure.
24 - 3.2.4 Choice of a reliability characteristic.
25 - 3.2.5 Required value of the reliability characteristic.
25 - 3.2.6 Choice of a maintainability characteristic.
25 - 3.2.6.1
25 - 3.2.6.2
25 - 3.2.7 Required value of the maintainability
25 - characteristic.
25 - 3.2.8 Operating regime and conditions.
25 - 3.2.9 Reliability and maintainability assurance.
26 - 3.3 SPECIFICATION OF RELIABILITY AND
26 - MAINTAINABILITY IN PRACTICE.
27 - SECTION 4 - ASSESSMENT AND PREDICTION OF RELIABILITY AND MAINTAINABILITY
27 - 4.1 GENERAL.
27 - 4.1.1 Aims of reliability assessment.
27 - 4. 1. 2 Reliabi l ity and maintainabi l i ty
27 - characteristics.
27 - 4.2 RELIABILITY ASSESSMENT.
27 - 4. 3 RELIABILITY PREDICTION BY
27 - MODELLING.
27 - 4.4 PROVISION OF RELIABILITY DATA.
28 - 4.5 RELIABILITY GROWTH TESTING.
28 - 4.5.1 General.
28 - 4.5.2 Preparation.
28 - 4.5.3 Results of reliability growth testing.
28 - 4.5.4 Factors governing reliability growth testing
28 - effectiveness.
28 - 4.6 RELIABILITY DEMONSTRATION AND TESTING.
28 - 4.6.1 General.
28 - 4.6.2 Aims of a test program.
29 - 4.6.3 Choice of test program.
29 - 4.6.4 Evaluation of test data using Bayesian methods.
29 - 4.6.5 Proof test.
29 - 4.6.6 Suitability of statistical methods for analysis of
29 - test results.
29 - 4.7 MAINTAINABILITY PREDICTION.
29 - 4.7.1 Maintainability prediction.
29 - 4.7.2 Prediction advantages.
29 - 4.7.3 Techniques.
29 - 4.7.4 Basic assumptions and interpretations.
29 - 4.7.5 Elements of maintainability prediction
29 - techniques.
30 - 4.7.5. 1
30 - 4.7.5. 2
30 - 4.8 MAINTAINABILITY DEMONSTRATION AND TESTING.
30 - 4.8.1 General requi rements.
30 - 4.8.2 Maintainability testing program.
30 - 4.8.3 Maintainability demonstration.
30 - 4. 8.4 Test conditions.
30 - 4.8.5 Maintenance task selection.
30 - 4.9 COMPLIANCE ILLUSTRATION BY MEANS
30 - OTHER THAN TESTING.
31 - SECTION 5 - PRODUCTION, FLOW, ANALYSIS AND INTERPRETATION OF RELIABILITY AND MAINTAINABILITY DATA
31 - 5.1 GENERAL.
31 - 5.1.1 Benefits.
31 - 5.1.2 Organization.
31 - 5.1.3 Effectiveness of communication.
31 - 5.2 DATA INPUT.
31 - 5.2.1 Reporting systems.
31 - 5.2.2 Specification and description.
36 - 5.2.3 Operating history.
36 - 5.2.4 Failure history.
36 - 5.3 DATA SOURCES.
36 - 5.3.1 Guidelines.
36 - 5.3.2 Past experience.
36 - 5.3.3 Design and development.
36 - 5.3.4 Production.
36 - 5.3.5 Factory test.
36 - 5.3.6 Guarantee or warranty reports– product
36 - liabi lity test reporting.
37 - 5.3.7 Supply of replacement parts.
37 - 5.3.8 Material or component supply.
37 - 5.3.9 Repair department.
37 - 5.3.10 Field installation, demonstration or
37 - commissioning tests.
37 - 5.3.11 User reporting system.
37 - 5. 3.12 Field surveys.
37 - 5.4 DESIGNING THE DATA COLLECTION
37 - FORM.
37 - 5.5 VALIDITY OF DATA.
37 - 5.5.1 Product manufacturer.
38 - 5.5.2 Materials or component supplier.
38 - 5.5.3 Field data retrieval programs.
38 - 5.6 COLLECTION AND FLOW OF RELIABILITY
38 - DATA.
38 - 5.7 ANALYSIS OF DATA.
38 - 5.7.1 Quantitative data.
38 - 5.7.2 Qualitative data.
39 - 5.7.3 Requirements specifications.
39 - 5.8 FAILURE CLASSIFICATION.
39 - 5.9 INTERPRETATION AND PRESENTATION
39 - OF DATA.
40 - APPENDIX A - TERMS FOR RELIABILITY AND MAINTAINABILITY
40 - A1 SCOPE
40 - A2 CLASSIFICATION OF FAILURES AS TO CAUSE
40 - A2.1 Misuse failure
40 - A2.2 Inherent weakness failure
40 - A3 CLASSIFICATION OF FAILURE AS TO SUDDENNESS
40 - A3.1 Sudden failure
40 - A3.2 Gradual failure
40 - A4 CLASSIFICATION OF FAILURE AS TO DEGREE
40 - A4.1 Partial failure
40 - A4.2 Complete failure
40 - A4.3 Intermittent failure
40 - A5 CLASSIFICATION OF FAILURE IN COMBINATION OF SUDDENNESS AND DEGREE
40 - A5.1 Catastrophic failure
40 - A5.2 Degradation failure
40 - A6 RELIABILITY CHARACTERISTICS
40 - A6.1 Observed reliability.
40 - A6.2 Assessed reliability
40 - A6.3 Extrapolated reliability
41 - A6.4 Predicted reliability
41 - A7 MEAN LIFE
41 - A7.1 Observed mean life
41 - A7.2 Assessed mean life
41 - A7.3 Extrapolated mean life
41 - A7.4 Predicted mean life
41 - A8 FAILURE RATE
41 - A8.1 Observed failure rate
41 - A8.2 Assessed failure rate
41 - A8.3 Extrapolated failure rate
41 - A8.4 Predicted failure rate
41 - A8.5 Assumed failure rate
41 - A8.6 Failure rate level
42 - A9 MEAN TIME TO FAILURE.
42 - A9.1 Observed mean time to failure
42 - A9.2 Assessed mean time to failure
42 - A9.3 Extrapolated mean time to failure
42 - A9.4 Predi cted mean time to failure
42 - A10 MEAN TIME BETWEEN FAILURES
42 - A10.1 Observed mean time between failures
42 - A10.2 Assessed mean time between failures
42 - A10.3 Extrapolated mean time between failures
42 - A10.4 Predicted mean time between failures
42 - A11 DATA CONCEPTS
42 - A11.1 Test data
43 - A11.2 Field data
43 - A11.3 Accelerated test
43 - A11.4 Acceleration factor
43 - A11.5 Failure rate acceleration factor
43 - A11.6 Step stress test
43 - A11.7 Screening test
43 - A11.8 Laboratory reliability test
43 - A11.9 Field reliability test
43 - A12 DESIGN CONCEPTS
43 - A12.1 Redundancy
43 - A12.2 Active redundancy
43 - A12.3 Standby redundancy
43 - A12.4 Storage life
43 - A12.5 Wear-out
43 - A12.6 Rating
43 - A12.7 Burn in
43 - A12.8 De-bugging
43 - A13 TIME CONCEPTS
43 - A13.1 Active preventive maintenance time
43 - A13.2 Administrative time
43 - A13.3 Undetected failure time
43 - A13.4 Maintenance time
44 - A13.5 Preventive maintenance time
44 - A13.6 Corrective maintenance time
44 - A14 Q-PERCENTILE LIFE
44 - A14.1 Observed Q-percentile life
44 - A14.2 Assessed Q-percentile life
44 - A14.3 Extrapolated Q-percentile life
44 - A14.4 Predicted Q-percentile life
44 - A15 MAINTENANCE CONCEPTS
44 - A15.1 Level of maintenance
44 - A15.2 Line of maintenance
45 - APPENDIX B - EXPLANATION OF RELIABILITY AND MAINTAINABILITY TERMINOLOGY
45 - B1 GENERAL - PRINCIPLES
45 - B2 FAILURE TERMS
45 - B3 THE NEED TO USE THE APPROPRIATE ADJECTIVAL MODIFIER
45 - B4 GENERAL STATEMENT ON THE PROBABILISTIC NATURE OF RELIABILITY
45 - B5 RELIABILITY CHARACTERISTICS
45 - B6 VERSIONS OF RELIABILITY CHARACTERISTICS
46 - B7 ACHIEVED AND REQUIRED RELIABILITY CHARACTERISTICS
46 - B8 PRACTICAL APPLICATION OF APPENDIX A
46 - B9 MEANING OF THE TERM ‘ITEM’
46 - B10 ‘HARDWARE’ TERMS
46 - B11 TIME CONCEPTS
47 - INDEX OF TERMS FOR RELIABILITY AND MAINTAINABILITY

Provides guidance on reliability and maintainability program management, and discusses the essential features of planning, organization, direction and control of resources to produce products which will be reliable and maintainable.

This Standard provides guidance on reliability and maintainability program management of manufactured and constructed products. It discusses the essential features of a comprehensive program for the planning, organization, direction and control of resources to produce systems, equipment and components which will be reliable and maintainable. In management terms it is concerned with what has to be done, and why, and when and how it has to be done, but it cannot be specific about who should do it and where, because organizations and projects vary widely.Section 2 reviews the essential features of a comprehensive reliability and maintainability program, setting out a logical framework in which the activities described in the other Sections can take place.Section 3 describes the steps that should be followed when a specification of reliability and maintainability is drafted. The Section provides guidance on the inclusion of reliability and maintainability clauses in specifications relating to the performance, construction, testing and installation of manufactured products, and indicates the nature of the reliability and maintainability statements appropriate to each specification.Section 4 is an introduction to the means by which quantitative values can be assigned to the reliability and maintainability of systems, equipment and components at various stages in their life cycle, and the factors that influence that assignment.Section 5 describes the processes of assimilation and utilization of the data on which assessment and prediction of reliability and maintainability are based.Appendix A provides the user with a supplementary list of terms for reliability and maintainability, taken from IEC Publication 271, which are not found in AS 1057.NOTES:1. Appendix B provides an explanation of reliability and maintainability terminology.2. Appendix C provides a complete index of terms for reliability and maintainability.3 Many but not all of the program elements described in this Standard are applicable to the achievement of reliability and maintainability of services.