What are some methods to select the proper plastic sheet material? Apply the tools that the professionals use to locate the best plastic material for their application.
Where To Begin The process of picking the proper plastic material starts with specifying the' must have' physical properties needed for your application. Designing a part with the minimum performance factors in intellect will help to eliminate an overly expensive part. Critical factors to consider are: Temperature needs (short term and long term) Environmental Needs UV resistance (Will it be in direct sunlight) Color or Transparency Strengths (Impact and Compression) Compliance Issues (Certification for FDA, NSF, Dairy, etc .) Review A Plastic Property Comparison Chart The first tool proposed is a map produced by the IAPD (International Association of Plastic Distribution - http:// iapd.org /) related in portrait below, and listed on this chart are the most common plastic sheet and plastic pole materials that are commonly available. In addition, the chart compares the physical properties of these common plastic materials. Click on scene to access map. IAPD Plastic Selection Rectangle Chart Included in this chart is a relative cost comparison, which will assist in limiting information materials to proper plastics for a application without over-designing and using an expensive' over kill' substance. Some common plastic sheet substances can be very expensive. Substances like PEEK (Polyetheretherketone) can be in the $100 per pound range or more. Begin The Search With Temperature Resistance After looking over the IAPD Physical Properties Chart , now it is time to evaluate specifics for your application. The crucial factor listed above are ranked by most important to least important. If your part needs to handle a continuous temperature of 300 degrees F, this is a critical physical property. Picking training materials that softens at 250 degrees is a recipe of natural disasters. Pick a material that can manage the temperature first. Does Your {Desired End Part|Part| Have Chemical Exposure Next, look at environmental requirements. Portions exposed to compounds are important to research. Find the chemical make up and the concentration of the chemical to insure the material you pick can handle this solution. Many plastics have excellent chemical opposition as evidenced by evaluating the container the compounds are stored in already. A common plastic the hell is compound resistant is Polypropylene, the same material used for automotive batteries. While Polypropylene and HDPE sheets are excellent in compound resist, their temperature scope is quite limited. Also, these two plastics can not be easily bonded or glued, and would require hot welding for assembly. Will Your Part Live In The Sun Most plastics do not manage long exposure to aim sunlight without an additional UV additive. The one exception is Acrylic, which is the most UV resistant plastic sheet available. Some plastics manage UV well if they have a carbon black additive, or a extra UV package added at period of production. How Critical Is The Color The most common colourings in many plastic sheets are Natural( white to tan) and Black. While other colors are available with a special running, this may require a large minimum order. Some plastics, like HDPE are available in many colors and textures for use in marine, playground and food processing applications. In many plastic applications, a machined part is being induced, and the colour is the least important factor. If it is an internal part of a machine , no one Acetal versus Delrin really cares about the colour of the part. Some patrons look for materials in a specific color to aid' brand' their components for easy substitution and identification. How Much Stress Will The Part See Strength is a wide range of physical properties embracing many stress a part may be exposed to. From impact to compressing, expansion to tensile strength, all of these can be critical in designing a plastic part. There are other factors in the' Strength' realm, like Notched Izod and Stress Can Cause Your Plastic Part to Bow, Twist and Crack, sea absorption. If your part will be exposed to crushing pressure, drawing apart army or impact, these are critical things to consider prior to picking your plastic component. PTFE is a soft and slippery plastic, but will' cold flow' under high pressure, and High Pressure Laminates like G-10 FR 4 sheet can withstand some of the highest pressures. The Notched Izod exams for materials that violate easily if a scored recognize has been attained in the surface. Acrylics violate quite easily if scored, but UHMW will not violate at all under the same exam. What Agency Approval May Be Required In many applications a part may require approval or testing to meet a third party certification. One such common application is for substances in food processing applications. Common requests included UL ratings, Fire Ratings, Military specifications and many more. Food contact is a popular request, encompassing substance that is either FDA( Food and Drug Administration) or NSF( National UL Ratings for Plastic Materials Sanitation Foundation) approved. These bureau insure that substances are rigorously tested and comply with their requirements for safety. Some common substances being implemented in food processing that fulfills the FDA certification are Delrin- Acetal, HDPE, UHMW and Nylon, plus many others. Once these steps have been completed, several materials should present themselves as meeting your criteria and physical property requirement. Regrettably there is no one perfect plastic that works in all applications. However, for almost every application, there is a material that will work,
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