June 05, 2012, Greg McKnight
There are many reasons why you might need testing services, but here are three of the most common:
1. Satisfy requirements by governing authorities or manufacturer specifications
For many industries where human safety is a primary concern, governing authorities and manufacturers utilize testing to prove product effectiveness, function and safety. The aerospace and medical industries leverage the most resources in this effort. Orthopedic implants, for example, are medical devices that are implanted into the body to repair fractures, replace joints and perform other key mechanical functions. Their reliability and success rate must be high, so the FDA has well defined and stringent guidelines for testing these devices. Likewise, the aerospace industry is responsible for transporting millions of people every year, so the FAA makes sure that manufacturers have thoroughly evaluated products through rigorous testing programs. Of course, commercial manufacturers in all industries have a vested interest in the success of their products and public safety, so they too impose internal testing requirements to add an additional level of reliability.
2. Collect empirical data to prove product design or define material properties
Companies that develop new products need to rely on material property data to optimize their design. This includes static tests to provide information such as stress strain curves, elastic modulus and Poisson ratio, as well as fatigue information like S-N curves (stress level vs. number of cycles to failure) and fatigue crack growth. In today’s technologically driven environment, new materials such as composites and metal alloys are being produced at a rapid pace and testing is required to provide the material property information that is in turn used in the design process. As an added level of assurance, new products are often tested in their finished state to determine failure modes and verify proper strength and function before being sold commercially.
3. Validate FEA (Finite Element Analysis) model
Usually, the product development process involves finite element analysis, or FEA. Specialized software can take a 3-dimensional model of a part and apply theoretical forces to it to analyze stresses and deformations. It’s a key tool in optimizing design without several iterations of prototypes and testing. Today’s FEA software has more functionality and is easier than ever to use, though this can result in problems, too. It’s relatively easy to generate an FEA model, but takes an appreciable level of expertise to know if your model is accurate. The pros know the most effective way to validate an FEA model is to physically test the part and compare the results to the predicted model. Adjustments can then be made and the model optimized. The advantage is that subsequent design iterations can be performed on the computer and not in the lab, saving time and money.
So that’s why!
The end goal of testing is to prove product effectiveness, function and safety. It takes qualified personnel and specialized equipment to do it right. This includes proper traceability of measurements to standards such as NIST and ensuring that the setup and results are accurate. Using an accredited lab like Accutek provides the highest level of assurance obtainable. Commercial test labs are very experienced in providing appropriate solutions for all the reasons you might need testing.