Failure Mode and Effects Analysis

FMEA (Failure Mode and Effects Analysis) is a preventive risk analysis tool that allows for the identification and management of potential critical issues in a product or process before they occur. The first formal applications of FMEA date back to the American aerospace industry during the Apollo project; subsequently, from the early 1970s, the American and Japanese automotive industries adopted FMEA to prevent the need for costly recall campaigns. Today, it is applied in a wide variety of manufacturing sectors due to its proven validity and applicability.

In the context of Lean Thinking, FMEA is the tool that transforms quality management from reactive to proactive: instead of correcting defects after they have occurred, the causes are anticipated and action is taken before the problem reaches the customer.

The objectives of FMEA

FMEA pursues six fundamental objectives:

• To identify preventively Potential defects and critical issues that can occur during a product's lifecycle

• Determine the causes of potential defects associated with design or manufacturing

• Predict the consequences in the interest of customer satisfaction

• Set intervention priorities based on the severity, likelihood of occurrence, and detectability of the defect

• Identify corrective and preventive actions more appropriate

• Document the choices made, contributing to the construction of a growing company technical memory over time

The fundamental concepts

Failure mode

The way a component or process can fail or exhibit a loss of performance. It is generally associated with a defect or non-conformance.

Effect

The impact on the customer if the failure mode was not anticipated or corrected. The customer can be internal (the next stage of the process) or external (the end customer).

Cause

A criticality that determines a failure mode. The causes are sources of variability associated with the input variables of the process.

Risk Priority Index (RPI)

The synthetic parameter that measures the criticality of each failure mode, calculated as the product of three factors: Gravity (user impact), Occurrence (probability that the cause will occur) and Detectability (ability of current controls to detect the defect before it reaches the customer). The higher the IPR, the more urgent the intervention.

Design FMEA and Process FMEA

FMEA can relate to both the product design phase and the production process. Therefore, a distinction is made between:

• Design FMEA Analyze failure modes related to design choices: geometries, materials, tolerances, interfaces between components. The object of the analysis is the product and its functional characteristics.

• Process FMEA — analyze failure modes related to manufacturing stages: processing, assembly, inspections, handling. The object of the analysis is the process and its operational variables.

The two analyses are complementary and allow for a systematic synthesis of the designer's and technologist's assessments. The development of the FMEA is always carried out through group activity, where the fundamental role is entrusted to the designer or the person responsible for the analyzed process.

When to apply FMEA

FMEA is the appropriate tool in all situations where preventing a defect is more valuable than correcting it. It applies when:

• A new product is developed or an existing one is modified before going into production.

• Design or redesign a production process

• Recurring defects that were not caught by existing controls are analyzed.

• The goal is to systematically reduce the costs of poor quality - scrap, rework, returns, and complaints.

• Regulatory or customer requirements must be met that require a formal risk analysis.

The most common errors in applying FMEA

• Implement it as a documentary exercise rather than an operational tool — An FMEA compiled in a conference room without input from those who work in the process produces a formally correct document that is operationally useless.

• Do not update the FMEA after corrective actions — The FMEA is a living document. If preventive actions are implemented but the RPN isn't recalculated, the effectiveness of the interventions is lost.

• Focus only on failure modes with the highest IPR. — A high IPR can depend on poor detectability even for a minor defect. Analyzing the IPR composition is more useful than reacting only to the total value.

• Do not involve all affected functions. — FMEA requires input from design, manufacturing, quality, and, where necessary, suppliers and customers. A single-department analysis produces a partial view of the risk.

• Treat it as a one-time activity — The FMEA must be reviewed whenever the product, process, or context of use changes. An FMEA that remains static from the time of product launch does not reflect the current operational reality.

FMEA in the Lean World Class® Method

In the Lean World Class® method, FMEA is the tool that ensures quality in the preventive phase, reducing the costs of non-quality before they manifest in the production process or—worse—at the customer's. It is an integral part of product development programs and production process improvement initiatives.

Do you want to see how FMEA is applied in a real project? Discover the method Lean World Class® developed by Bonfiglioli Consulting