Industrial Glossary

L’FMECA (Failure Modes, Effects and Criticality Analysis), or FMEA in English (Failure Mode and Effects Analysis), is a preventive and systematic analysis method used to identify, evaluate and prioritize potential product or process failures, as well as their impact on the customer or the system.

In-depth definition : FMEA is a fundamental tool in the management of risk. Quality and Industrial Engineering. It applies before the Series Production (at the’Industrialisation) or before implementing a new process. Unlike the Root Cause Analysis (RCA) which is reactive (it analyzes a problem after that it has occurred), the FMECA is proactive. It seeks to answer three questions:

1. What are the possible faults? (Failure modes)
2. What are the consequences? (Effects)
3. What are the priority actions to prevent them? (Criticality and preventive actions)

The Three Types of FMECA

FMECA is generally structured according to the point in the product life cycle at which it is applied:

1. Product FMEA (FMEA Design) : Used by the design team to analyze potential failures related to the product itself (materials, shape, tolerances, product specifications, etc.). Technical specifications). The aim is to ensure that the product is intrinsically reliable.
2. Process FMEA : Used by the Methods or Industrialisation to analyze potential failures in the Manufacturing range and assembly steps (operator error, incorrect machine setting, use of wrong tools). The aim is to ensure that the process is capable of producing the product reliably and in accordance with the customer's specifications. Manufacturing file.
3. Equipment FMEA : Used by the Maintenance to analyze production equipment failures (cause of breakdown, need for maintenance, etc.). Preventive Maintenance or Predictive Maintenance).

Criticality calculation (IPR)

The heart of FMECA is the determination of the’Risk Priority Index (RPI) for each identified failure mode. The RPN is the product of three ratings (generally on a scale of 1 to 10):

IPR=Graviteˊ×Occurrence×Deˊtection

1. Gravity (G) : Assessment of the severity of the effect of the failure on the customer or user (impact on safety, functionality, etc.). Quality).
2. Occurrence (O): Estimate of how often the cause of the failure will occur.
3. Detection (D) : Assessment of the capacity of the current control system (inspection, Poka-Yoke, Machine Vision) to detect failure before before it reaches the customer or the downstream stage.

Failure modes with the highest RPN (the famous 20 % critical identified by the Pareto method) are those requiring immediate corrective action, as their risk is deemed unacceptable.

FMECA and Operational Excellence

FMECA is a powerful tool for the’Operational Excellence because it forces teams to anticipate problems:

• Risk prevention : It can be used to implement risk-reduction measures (e.g. adding a device to an existing system). Poka-Yoke or modification of the Bill of materials - BOM) before failure becomes costly.
• Standardization support : The actions selected to reduce the RPN (e.g. improve detection or reduce occurrence) are integrated into the Work Instructions and Manufacturing file, reinforcing the Standardization.
• KAIZEN power supply : Each time a failure occurs despite the FMECA, the analysis is updated, the assumptions are corrected, and the new risk level is integrated into the cycle. PDCA (Plan-Do-Check-Act) for a Continuous Improvement (KAIZEN).

In conclusion, the’FMECA is the methodological tool that enables an organization to transform its approach to problems, moving from a reactive posture (suffering breakdowns) to a proactive posture (preventing them), thus guaranteeing the reliability and efficiency of its processes. Industrial Performance sustainable.