Committees responsible
National foreword
Introduction
Guide
1 Scope
2 Normative references
3 Definitions
4 Symbols
5 General description
6 Planning
7 Pilot-production screening
8 Mature production screening
Annexes
A (informative) Stress conditions: general information
B (informative) Stress conditions: temperature
C (informative) Stress conditions: vibration and bump
D (informative) Stress conditions: humidity
E (informative) Stress conditions: operational stress
F (informative) Bimodal distributions - Weibull
plotting and analysis
G (informative) Evaluation of the failure-free
period and the average screening duration
H (informative) Worked-through example
Tables
A.1 Stress types - indication of cost of application
H.1 Relations between the sensitivity of flaws and
stresses
H.2 Observed failure ranks and times to first failure
for the pilot production
H.3 Revised rank values
Figures
1 The conceptual difference between reliability
screening and growth
2 Typical flow for the design and modifications of
reliability stress screening processes for
repairable items
3 A typical flow of hardward items from the component
manufacturer to the end user
4 Reliability stress screening of repairable items
5 Dependency of categories of failures
6 Elements of stress conditioning
7 The item must show a failure-free period Tm before
being accepted
8 Time graphs for determination of the failure-free
period
F.1 The S-curve for a bimodal Weibull distribution
mixed by
F1(t)=1-e (t/30) 1,5 and F2(t)=1-e (t/60 000) 1,5
F,2 Estimation of p, k1 and b1 for the purpose of
reliability screening optimization
F.3 The c.d.f's for bimodal exponential distributions
F.4 The hazard rate function for bimodal exponential
distributions
G.1 The basic system
G.2 An item with n weak components surviving the
screening period TM
G.3 Possible states, when a component fails during the
stress screening
G.4 Item states after failure and repair
G.5 Time graph for evaluation of the failure-free
screening period
G.6 Average screening duration versus the normalized
failure-free period TM/mF1
H.1 Derivation of the failure-free period TM
H.2 Derivation of the average screening duration
H.3 Observed figure pattern and predicted curve for
the pilot production
H.4 Pilot production screening plot of relevant
failures and predicted S-curve for the sole failures
taken into account
H.5 Time graph (corrected) for determination of the
failure-free period
H.6 Time graph (corrected) for evaluation of the
screening duration