FMEA methodology was created to solve a primary need of every company. The Brand, the reputation and even the survival of a company pass through the quality of its products and the relationship with its customers.
Nobody wants a defective product and defects are expensive, frustrating and harmful to the reputation of an organization.
The FMEA methodology can improve systems, design and manufacturing processes, helping to identify potential problems and enabling corrective action to be taken.
CONTENTS
Its acronym – FMEA – stand for Failure Mode and Effects Analysis.
Furthermore, this technique is also known as FMECA – Failure Modes, Effects and Critical Analysis.
FMEA is a simple, systematic and qualitative technique that involves brainstorming with experts and recording their comments in a table; a process similar to the creation of a probability and impact matrix, i.e. the matrix for risk assessment.
Experts identify and report in a table the possible causes of product failure, the likelihood of their occurrence, their effects and the probability that failures will be detected before they happen.
This allows them to identify many failures that may affect the end result.
Used in many industries, the FMEA methodology is one of the best ways to analyze potential reliability issues early in the development cycle, making it easier to quickly take action to mitigate or eliminate failures.
When to use the FMEA methodology and its different types
The FMEA is beneficial to prevent future errors and improve process and product reliability in general.
This methodology can be used in the following cases:
- During the development of a new product or process.
- Before modifying a product or process.
- After having identified an error in a product or process.
- When multiple and consistent complaints are received from customers.
- When sales support costs are uncommonly and exceptionally high.
- When the integrity of an organization is at stake.
The most used applications of the FMEA methodology are:
- Concept FMEA
- Design FMEA or DFMEA
- Process FMEA or PFMEA
Concept FMEA
This is developed at the very early stages of a product or process life cycle, i.e. when it is still in a conceptual phase.
It is performed at the system or subsystem level before the key requirements are set.
The concept FMEA helps to identify the factors that can be included in a product or process.
Design FMEA or DFMEA
Design FMEA is used to determine potential risks when designing a product or service.
The DFMEA is a methodological approach used to identify the potential risk on a new product design and examines the possibility of malfunctions, reduction in product life and safety and regulatory issues arising from, for example:
- Material properties;
- Shape;
- Intolerances;
- Interfaces with other components and/or systems;
DFMEA identifies the failure conditions of the design features and their possible effect on the end customer with the classification of the severity or danger of the effect.
Process FMEA or PFMEA
Process FMEA is used in the analysis of possible errors and risks in a process.
It detects faults that may affect product quality, reduced process reliability, customer dissatisfaction and risks to safety or the environment arising from, for example:
- Human factors
- Methods applied during processing
- Materials used
- Equipment used
- Impact of measuring systems on acceptance
- Environmental factors on process performance
How to implement FMEA methodology
The use of this technique requires experienced assessment.
One or more brainstorming sessions with specialists, will help to identify, collect and evaluate potential defects, their causes and impact.
Experts should fall within all functional areas so that the entire lifecycle of the product can be covered.
The FMEA methodology is based on three parameters: severity, occurrence and detection. Specifically:
- Severity (S) indicates the effect of the failure on the rest of the system if the failure occurs;
- Occurrence (O) indicates how often the problem may occur;
- Detection (D) is a measure of the effectiveness of current controls in place to identify potential defects before production.
Here is how the FMEA methodology is used, step by step:
- For each potential error or defect, experts will assign a value from one to ten, where one means “extremely unlikely” and ten is “extremely likely”.
- At the end of the brainstorming session, a list of problems will be generated, with their causes and assessments.
- Afterwards, this information will be added in a table.
- Lastly, the values for severity, occurrence and detection of each defect will be multiplied to generate an RPN. This will indicate the number of risk probabilities and provide an overall risk impact score for each defect.
- The thresholds of each risk level will be decided after generating RPN for all possible defects and failures. Using the RPN number, a decision will then be made whether a cause of the defect has high, medium or low priority.
- Work on high priority RPNs will begin to mitigate or eliminate the most important flaws.
- Determine the recommended actions. These actions can be design or process adjustments to reduce defects and problems.
- Once the actions have been carried out, note the results and the date in the FMEA form. In addition, it is important to take note of the new S, O or D value classifications and the new RPNs.
This is the description of a general procedure. Specific details may vary depending on the standards of the organization or industry.
Advantages of FMEA methodology
- Improved and more reliable products
- Less after-sales support
- Improved customer satisfaction
- Improved brand reputation
- Reduction of breakdown costs and warranty
- Profit maximization by reducing after-sales expenses
- Catalyst for teamwork and sharing ideas between different functions
Although this is a simple method and can allow teams to set priorities according to the highest RPN (Risk Priority Number), there are some weaknesses to be taken into account before adopting this methodology.
- Scope problem. Once the key problems have been solved, what is the limit point for further improvement? If every problem, even the most trivial ones, ends up on an FMEA sheet, the specific meetings can become time-consuming and complex, constraining valuable hours during which the actual processes could be improved.
- FMEA methodology is only valid among FMEA team members. Problems that have not been experienced by team members will not be presented as possible error modes. When this occurs, the situation may even require the hiring of external consultants.
- FMEA methodology is an evaluation tool and, in itself, does not eliminate problems.
In conclusion, the FMEA methodology is a proactive technique to detect potential defects and failures before they happen.
It is an optimal method that, if used correctly and taking into account the limitations mentioned above, can bring many advantages to an organization.
