Reliability Analysis Services

GMR Solutions offers reliability analysis services for use during the design phase to identify and manage risks associated with product failure. The following two options for analysis provide risk assessment using different methodologies.

Risk assessment adds value to the development process by:

• Early identification of risk areas.
• Provides detailed understanding of failure modes, causes, and effects.
• Highlights possible areas of non detection.
• Eliminate failures before being designed into a product.

Failure Modes and Effects Analysis (FMEA)

Developed in the late 1940's by the US Military to classify failures according to their impact on mission succes and personnel/equipment safety. Since conception, the process of FMEA has spread to a wide range of applications including commercial product development, and manufacturing operations.

FMEA is the process of identifying risks at sub system level, assigning a severity (S), likelihood of occurrence (O, or P) and defining the inability of a control to detect the failure (D).

The product design is analysed by:

• Breaking up the complete system into sub sections.
• Assigning a risk of failure to each section.
• Listing all possible failure modes and causes.
• Listing the systems ability to detect all failure modes.

The purpose of the FMEA is to take actions to eliminate or reduce failures, starting with the highest-priority ones. It is typically applied as a top down reliability assessment tool.

Fault Tree Analysis (FTA)

Fault Tree Analysis is a logical analysis of reliability risks. It is a top down type system, which defines a root (failure mode) and identifies possible failure causes for that particular failure mode. Each possible cause of failure is added to the fault tree, typically using standard logic gate symbols (OR, AND, etc).

By identifying each failure cause the risk of failure can be mitigated through design alterations, and component derating or selection. By conducting discussions with design engineering it is often possible to mitigate each failure cause through some action. This action may be taken in design, maintenance, or even procedures.

The steps to conducting an FTA are:

• Define a top level event - failure type.
• Logically draw out each possible cause of failure.
• Assign a counter measure to each cause.
• Continue for all sections of the product.

Which Analysis Technique to Use

Either analysis technique may be used during product design. Before prototypes are constructed is the best time to conduct the analysis to avoid designing in failures. Use the following as a rough guide for selecting the appropriate type of analysis:

• Use a FMEA/FMECA when:
  • The failure events cannot be limited to a small number.
  • Identification of all possible failure events is critical.
  • Product functionality is able to be split into sub sections.
• Use an FTA when:
  • A small number of top events can be identified.
  • The product functionality is highly complex.
  • The product is not repairable once in service.

Contact us and provide more information about your product application and type, and we'll provide our recommendation for which method would be more beneficial.