What is a Failure Mode and Effect Analysis (FMEA)?

Today we will discuss FMEA – Failure Mode and Effect Analysis.

No one wants a defective product. Defects are costly, frustrating, and damaging to a company’s reputation.

As a project manager, you will try to avoid failure in your deliverable using every possible technique. One such technique is Failure Mode and Effect Analysis, or FMEA. This technique helps you locate potential issues with a product or process and allows you to takecorrective action.

FMEA – Failure Mode and Effect Analysis

The US military developed FMEA to design better weapons, and this methodology was successful. Later it was adopted by NASA, automobile companies, and then other industries.

FMEA is a methodology that helps organizations to anticipate system or product failure during the design stage by identifying all possible failures in a design or manufacturing process.

FMEA was one of the earliest methods of systematically looking at the potential problem in a product or process.

It looks at similar products or processes and reviews their past failures. It also considers the physical characteristics of the material. Depending on your analysis, you can make changes in processes or products to avoid errors.

故障模式是产品或过程可能失败的方式。影响是这些失败会导致缺陷的方式。故障模式和效果分析旨在识别，优先级和控制这些故障模式。

This technique is also known as “Failure Modes Effects and Criticality Analysis” (FMECA) or sometimes simply “failure modes.”

The FMEA can improve your systems, design processes, and production processes.

FMEA is a straightforward, qualitative technique that involves brainstorming with experts and listing their comments in a table. It is similar to the process of creating aprobability and impact matrix.

Here, experts identify possible causes for product failure, the chances of these happening, the impact, how easy it is to detect failure, etc. These opinions are noted in a table for further review.

This helps you identify many failures that can affect the deliverable.

Types of FMEA

FMEA can be broadly divided into two categories:

1. Design FMEA
2. Process FMEA

Design FMEA (DFMEA)

DFMEA finds possible failure modes during the design stage, such as:

• Tolerance
• Material properties
• Product geometry
• EEF

Process FMEA (PFMEA)

PFMEA finds possible failure modes that can occur during the product development process, such as:

• Procedure
• Human error
• Equipment used
• Inspection

When to Use FMEA

FMEA is useful for avoiding future errors and improving the reliability of the process and the product. You can use it in the following cases:

• During the development of a new product or process.
• Before you make changes to a product or process.
• After identifying an error in a process or product.
• When receiving numerous and consistent complaints from customers.
• When sales support costs are unusually high.
• When a company’s credibility is at stake.
  

This technique is not confined to any industry or technology; you can this method in all industries.

How to Use FMEA

This technique requires expert judgment. You will call experts for one or more brainstorming sessions. They will help you identify, collect, and evaluate the potential defects, their causes, and their impact.

The experts should belong to all functional areas so you can cover the complete产品生命周期.

FMEA Example

You can use the following table to record the experts’ input. You will pay more attention to analyzing the causes of possible equipment failure.

The FMEA technique uses three parameters: severity, occurrence, and detection.

Severity (SEV) shows the harshness of the defect on the user. Occurrence (OCC) predicts how often the issue may happen. Detection (DET) represents how easily you can find the problem.

Experts will assign a value from one to ten for each potential error or defect, where one is extremely unlikely, and ten is extremely likely. After the brainstorming session ends, you will compile the problems, causes, and ratings. Afterward, you will enter this information into a table.

Finally, you multiply the severity, occurrence, and detection of each defect to generate an RPN. This stands for Risk Probability Number and provides an overall risk impact score for each defect. In our example table, the RPN for the failure is 81.

You will decide the thresholds of each risk level after generating the RPN for all possible defects and failures. The threshold can be high, medium, or low. Using the RPN number, you will decide if a defect cause is high, medium, or low-level priority.

You will work on the high-priority RPNs to mitigate or eliminate defects.

For example, the second table shows your recommended action for an identified failure, who will be responsible for the action, and when you should implement it.

You will record this failure and the action taken on it once it happens.

How to Implement FMEA

You have a list of possible errors and their potential corrective actions. Now, you will assign responsibility to your team members to implement these actions to reduce the RPN of these errors.

在实施纠正措施以评估行动计划的有效性之后，您将再次审查它们。如有必要，将生成新的FMEA，以重新评估风险和缺陷。

Use thePareto Lawwhile using this technique. Focus on the minority of causes creating most of the issues or defects. This provides the most significant impact while using the least resources. You can take on the other defects, as resources permit, once these high-impact issues are resolved.

You can plan a new corrective action to mitigate the problem if you see that a particular issue is not being resolved currently.

Importance of FMEA

Finding and correcting failures early is much less costly than finding them at a later stage. An error at a later stage is more damaging as it affects brand recognition and dissatisfied customers.

FMEA lets you find failures in the early stage of product development.

It reduces after-sales support and increases customer satisfaction.

Benefits of FMEA

A few benefits of FMEA are:

• Improved and more reliable products.
• Less after-sale support.
• Increased customer satisfaction.
• Improved brand reputation.
• Reduced failure and warranty costs.
• Maximized profits by reducing after-sales expenses.

Conclusion

FMEA is a proactive technique that helps you to identify potential defects and failures before they occur. This is a fantastic qualitative method, and if used correctly, can bring many benefits to your organization. Though this technique is time-consuming due to the involvement ofvarious stakeholders, it will lead your project to a successful ending.

Please share your experiences with the Failure Mode and Effect (FMEA) Analysis technique in the comments section.