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.
The focus should be 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 these:
- a design for reliability manual,
- a derating & safety margin manual,
- a project-specific reliability plan, and
- an environmental testing manual.
In this article, let’s discuss the design for reliability manual. Subsequent articles will introduce and outline the other documents.
Design for Reliability Manual
The design for reliability manual includes a brief overview of your organization’s policy concerning reliability performance. It should primarily focus on sections that 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
Potential chapters should include a short outline on how to set reliability goals, with the factors to consider for early life, warranty, and serviceable life (or appropriate timeframes for your products).
A short tutorial on reading Weibull CDF plots would be useful to include, as would a brief introduction to reliability statistics and data analysis.
An overview of risk identification tools, such as FMEA and HALT, may avert unnecessary time wasting by team members seeking definitions. Provide basic FMEA and HALT steps to accomplish as these will assist teams in understanding what and how to accomplish these tasks and also provide reasonable resource requirements.
An introduction to reliability-related design practices such as derating and safety factors along with the concept of the stress–strength relationship should also be included. This section can provide the motivation 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. Indicate what questions to ask, what data to review (and how to conduct the review), and best practices to minimize supplier-related reliability issues.
The warranty and field data analysis process not only serves customers but, when done well, also constitutes a wonderful source of information for the design and development team. Include an overview of the process and an outline of the processes to set warranty expectations (accruals based on reliability estimates), as well as data collection and reporting methods that provide value to the different parts of the organization.
The above gives 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.
Moving Forward
This article is intended to just provide an outline for an essential document for your reliability program. The actual document should provide policy and overview plus specific procedures and guidelines. The intent is to create and distribute a repository of information that will help your organization both understand and accomplish its part in the creation of a reliable product.
Bio:
Fred Schenkelberg is an experienced reliability engineering and management consultant with his firm FMS Reliability. His passion is working with teams to create cost-effective reliability programs that solve problems, create durable and reliable products, increase customer satisfaction, and reduce warranty costs. If you enjoyed this articles consider subscribing to the ongoing series at Accendo Reliability.