Failure Mode and Effect Analysis (FMEA)
FMEA is a method followed mainly by engineer, for improving a process by analysing designs and processes for potential failures. Through a highly structured and systematic method and means, FMEA is able to identify and assess the potential failures of the system. It can be used as a quality tool, by building in quality into the initial design therefore decreasing the risk of failure. Ty x detection
FMEA works in a bottom up approach, by listing the potential failures through analysis and brainstorming sessions. An inductive tool, using a forward logic, it analyses further the effect of each failure. The result is a severity index, rating from 1 to 10. Then we need to assess the likelihood of happening (standard risk management), but also the likelihood of detecting the failure. A risk priority number (RPN) is given to each failure, which is the product of severity x probability x detection; and a table is created. The extra factor of detection is what signifies and differentiates FMEA from other analysis methods.
To identify the probability (or the reliability of the system/ process) we need to gather data. The data sources can be any data available, from the manufacturer, from other operators, from common databases etc. We can also create data through simulator and testing conditions (but we must be careful to accurately represent real life scenarios. If we find impossible to get real data, ten we can use statistical analysis and estimates, or past historical evidences of similar situations.
FMEA is mainly used by manufacturers ideally during the design process, but it can also be used in later stages for improving and checking. It should also be used anytime there is a redesign, modification or operators’ feedback. It is step-by-step, component- oriented process, meaning that the manufacturer this to pick as many individual components as possible and review/study them under the method. Assigning the RPN a document is created with the current issues, and then with the actions taken and rectifications made.
• Teamwork and idea exchange promoted between functions and departments
• Collects info and captures knowledge
• Early identification and elimination of failures during the design process
• Prevents problems in later stages
• Improves production, yield, image, reliability, safety and satisfaction
• Can be a great complementary tool for FTA
• Hard to produce
• Subjective assessment of failures
• Complexity of data