Product Reliability Design

One way to capture and disseminate reliability engineering related information and advice is through internal documents. This of course only works if they are both useful and used.

Focus on gathering and providing essential and meaningful information that will improve the reliability of your product. Another element that makes these design guidelines valuable is if they save time. Engineers love to save time.

Let’s break down a few documents that you should consider creating (or improving) for your organization. I recommend:

• Design for Reliability Manual
• Environmental Testing Manual
• Derating/Safety Margin Manual
• Project specific Reliability Plan

In this articles, let’s discuss the DFR Manual and in following articles introduce and outline the other documents.

Design for Reliability Manual

The DFR manual includes a brief overview of your organization’s policy concerning reliability performance.

It should primarily focus on sections which provide detailed ‘how to’ guidelines for the fundamental reliability tasks for your organization.

For example, you may include a chapter on reliability measures and reporting. This details the sources of data, best practices, and reporting methods.

Potential chapters may include:

A short outline on how to set reliability goals, with the factors to consider for early life, warranty, and serviceable life (or appropriate time frames for your products).

Possibly include a short tutorial on reading Weibull CDF plots. Plus, consider adding a brief introduction to reliability statistics and data analysis.

An overview of risk identification tools, such as FMEA and HALT may advert unnecessary seeking for definitions across the team. Provide basic FMEA and HALT steps to accomplish as it will assist teams to understand what and how to accomplish these tasks, plus provide reasonable resource requirements.

An introduction to reliability related design practices such as derating and safety factors, plus the concept of stress strength. This section can provide the motivation for and overview of the process, whereas it would reference the Derating/Safety Margin Manual for details.

Given the importance of supplier components to the overall product reliability, detail a section that provides sufficient guidance for your teams working with suppliers. What questions to ask, what data to review (and how to review it), and best practices to minimize supplier rated reliability issues.

The warranty and field data analysis process not only serves customers it also is, when done well, a wonderful source of information for the design and development team. An overview of the process and an outline of the processes to set warranty expectations (accruals based on reliability estimates), plus data collection and reporting methods that provide value to the different parts of the organization.

The above is just my suggested chapters. You should tailor this manual to best serve your organization by providing the elements that provide useful information for reliability practices and procedures that directly impact product reliability.

Summary

This is just an outline for an essential document for your reliability program.

It provides policy and overview, plus specific procedures and guidelines. The intent is to create and distribute a set of information that will help your organization both understand and accomplish their part in the creation of a reliable product.

In the next few articles we’ll discuss the:

• Environmental Testing Manual
• Derating/Safety Margin Manual
• Project specific Reliability Plan

Each of which also has an essential role in your program. If you have examples of these manuals you’d like to share, please let me know and we can post them to the site. Having a couple solid examples may help others create useful documents quickly.

Besides, you may want to gather a bit of feedback or input as others review and comment on your document.

---

Related:

Key Elements for Your Project Specific Reliability Plan (article)

Reliability Management & Risk (article)

Reliability as Part of Every Decision (article)