Root Cause and Failure Analysis

Large industrial facilities are made of numerous systems and sub-systems. Such systems contribute to the overall reliability of the entire unit. The reliability of the entire system is assessed through the process of probability safety analysis.  The course will provide an overview of system reliability analysis with a focus on the qualitative and quantitative methods. The principal methods presented in the course include fault tree analysis and event tree analysis.  Fault tree diagrams are used to model the possible combinations of equipment failures, human errors, and external conditions that can lead to a specific type of accident, while event trees are used to identify the possible consequence of events or accidents that lead to a particular consequence. Root Cause Failure Analysis is a very effective tool for improving the reliability of facilities, its sub systems and operation. It is a logical, structured, and deductive technique that can identify the causes behind the failure. The course will show how to identify root cause failure and analyze it in practical industrial applications.

Learning Outcomes:

1. Learn the fundamental concept of risk, reliability and failure analysis.
2. Survey a general knowledge and acquire a context perspective about risk, reliability and failure analysis in engineering systems.
3. Learn the essential physical principles on which industrial systems are based and to be able to identify root cause of failure.
4. Apply a combination of good engineering and good science.
5. Distinguish between the different types of system reliability analysis (fault tree analysis, event tree analysis, failure modes and effect analysis, reliability block diagrams and functional logic diagrams ..etc).
6. Identify the rules of failure analysis and fault tree construction.
7. Use reliability block diagrams to represent parallel and series systems.
8. Construct fault tree and event tree.
9. Interpret failures graphically.
10. Assess and analyze system failures qualitatively and quantitatively.
11. Identify the root cause of failure analysis and minimum cut sets.
12. Evaluate common cause failures through beta factor approach.
13. Identify the weakness in a system through criticality analysis and importance measures (Birnabaum, fussell-Vesely, risk achievement worth, risk reduction worth, risk increase ratio, risk decrease ratio).
14. Recognize the other aspects of failure analysis useful for inspection considering lifetime data.

• Risk/safety/reliability/​​ quality/maintenance managers and professionals.
• Operation/process/inspection/maintenance engineers.
• Personnel working in either the manufacturing sector or the service sector with interest in solving recurring ability.

Day 1

• An introduction to risk and reliability in engineering systems (definition of reliability, objectives of reliability analysis, types of reliability analysis, the basic reliability problem, risk definition, risk terminologies).
• Overview of Safety Analysis and System Reliability Analysis (fault tree and events tree, types of safety analysis, scope of probabilistic safety analysis, procedure of probabilistic safety analysis, limitations of probabilistic safety analysis, system reliability analysis, failures modes and effect analysis, reliability block diagrams, parallel and series systems , graphical interpretation of failures).

Day 2

• Fault tree analysis (basic events, advantages of fault trees, limitations of fault trees, notations used in fault tree construction, event symbols [gates symbols, transfer symbols], general procedure for fault tree analysis, rules of fault tree construction, considerations in fault tree construction).

Day 3

• Root cause failure and fault tree evaluation (Boolean algebra, qualitative analysis, root cause failure, top event, minimal cut sets, criticality, quantitative analysis, common cause)
• Failures [beta factor model], importance measures [Birnabaum importance measure, criticality importance measure, Fussell-Vesely importance measure, risk increase ratio (RIR), risk decrease factor (RDF)].

Day 4

• Failures and event tree analysis (event tree definition, initiating event, event tree model, advantages, limitations, procedure for event tree construction, failures locations in event tree, event tree evaluation).

Day 5

• Other aspects of failures analysis useful for inspection when considering lifetime data (hazard rate, bathtub curve: early failures, useful life period, wear out period, lifetime distribution models, impact of aging, challenges, data for failure identification: incomplete censored data, conceptual modeling of inspection data, complete lifetime data, complete and right-censored data, interval and right-censored data).