Requirements for such advantageous versatility often leads to the selection of plastic parts and components as solutions to meet criteria essential for a wide variation of competitive products, typically at a fraction of the cost of products made using traditional industrial materials.
While plastic parts are engineered for long life even in the most challenging conditions and are often sought for their resistance to substances, extreme temperatures, aggressive chemicals, humidity and UV light how designers, buyers and engineers go about specifying and have them manufactured varies. Often a review of similar existing applications is undertaken to learn which materials, processes, and designs have worked successfully. Specifiers often select a familiar grade of plastic from a similar application. Polymers chosen this way may be adequate but are rarely optimal.
Key to designing and manufacturing a plastic part for optimal performance in its given application involves many important factors that touch on all areas of part design, tooling, material selection and production. The relationship between design and manufacturing is key to developing a plastic part which performs well in its application. Discussing the application with experienced manufacturers and materials suppliers for their recommendations will bring significant value.
Temperature, length of exposure, presence of internal and external stresses, the mating surface and the presence of water or concentration of chemical(s) all affect the longevity of plastic parts. An ideal plastic part will have a value for each strength property just sufficient to perform properly, reliably and safely in a given application and no higher.
An ideal plastic part is usually made from a polymer chosen not because it has the highest values in any single category but because it usually represents a trade-off among satisfactory properties, ease of processing, and cost.