Design for Reliability

Typical Situations

You have a rather complex product that should function under well-defined operating conditions with a high intended useful lifetime?

Although failure modes would have catastrophic effects, you cannot simply test the complete product because it is too expensive and time-consuming?

You want to use reliability predictions to develop a maintenance strategy for your product to guarantee a high availability for operation?

Our Solution

Design for Reliability (DfR) or Reliability Engineering is a structured methodology that ensures to design reliability into products. Reliability is the probability that a product performs its intended function for a specified period of time under a specified set of operating conditions. This in contrast to Design for Six Sigma, which concentrates more on developing products that delight customers and are failure-free at market introduction.

Design for Reliability uses mathematical models to analyze and predict product reliability. These models are developed using block diagrams and fault trees to provide a graphical means of evaluating the relationships between the individual parts of the product. Life distributions of these individual parts are based on part-count failure rate taken from historical data (e.g. Weibull analysis) and are used to predict product reliability. Design for Reliability also utilizes accelerated life testing to induce field failure in the laboratory at a much faster rate by providing a harsher, but representative environment. In general, Design for Reliability has the following objectives:

• Develop mathematical models for predicting, analyzing and improving product reliability,
• Ensure that product failure modes are detected and occur beyond the specified lifetime period,
• Sustain product function robustness over specified lifetime under real-world usage conditions.

Our Method

The reliability experts of Innovensys have developed a Design for Reliability training curriculum that integrates well in your product development process and ensures successful application. It includes the following reliability methods:

• Lifetime Data Analysis (mttf, mtbf, etc.),
• Lifetime Model Selection & Fitting,
• Reliability Target Setting & Allocation,
• Reliability Block Diagram Analysis,
• Fault Tree Analysis (FTA),
• Failure Mode & Effects Analysis (FMEA),
• Reliability Improvement Plan,
• System Reliability Modeling and Prediction,
• Highly Accelerated Life Testing (HALT),
• Highly Accelerated Stress Testing (HAST),
• Highly Accelerated Stress Screening (HASS),
• Reliability Growth Analysis,
• Reliability Demonstration.