Nearly all forms of plastic are made from natural gas, oil, and some types of vegetation. Plastics have been demonized as a symbol of all that is wrong with society, but nearly everyone still uses them. Even the most vocal opponents express their disapproval using a plastic computer keyboard. The manufacturing method that makes these finished products possible is called thermoforming.
The environmental impact of hydrocarbon use is difficult to ignore. Surprisingly, production of plastics uses less than 3% of all the oil and gas burned each year in the United States by vehicles. That is still a huge number, but illustrates how halting all production of plastic would do very little to end reliance on oil as a primary fuel, and would force consumer prices upward.
The material used in this process begins as a continuous sheet of acrylic, polypropylene, polyvinyl chloride, or other similar polymer. That thin layer is carefully heated to the point that it becomes pliable, but not liquid. Using one of three methods, it is then applied to a specifically designed mold, allowed to cool, and trimmed. The result is a smooth, finished piece or component.
The sheets are commonly processed using radiant electrical heat coming from devices positioned around five inches away. The type of polymer being used determines how long the heat must be applied. Once pliable, there are three primary methods of achieving the final shape. The first is called vacuum forming, which uses negative pressure to draw the warm plastic into a mold.
Pressure forming is also possible using positive energy. Vacuum processes are limited by physics, but positive pressure reaches higher levels, making it a more versatile choice. In order to avoid thin spots, the sheets undergo pre-stretching. Once in place, the trapped air escapes via vents in the mold, and the cooled product is then ready to trim.
Some thermoplastic processes require molds with both positive and negative sides. The warm plastic is positioned between the two, and after appropriate pressure has been applied, the material assumes the size, shape, and detailing of the interior space. While this affords greater control, costs are higher. Regardless of the process chosen, only thermoplastics can be reheated safely.
Thicker gauges are used to make vehicle parts, medical industry accessories, electronic component housings, and are even important in some bathroom fixtures. Thinner gauges are perfect for packaging foods, cosmetic products, and numerous other small items such as screws or paper clips. While most are not biodegradable, methods of disposal and recycling are improving.
The environmental impact of hydrocarbon use is difficult to ignore. Surprisingly, production of plastics uses less than 3% of all the oil and gas burned each year in the United States by vehicles. That is still a huge number, but illustrates how halting all production of plastic would do very little to end reliance on oil as a primary fuel, and would force consumer prices upward.
The material used in this process begins as a continuous sheet of acrylic, polypropylene, polyvinyl chloride, or other similar polymer. That thin layer is carefully heated to the point that it becomes pliable, but not liquid. Using one of three methods, it is then applied to a specifically designed mold, allowed to cool, and trimmed. The result is a smooth, finished piece or component.
The sheets are commonly processed using radiant electrical heat coming from devices positioned around five inches away. The type of polymer being used determines how long the heat must be applied. Once pliable, there are three primary methods of achieving the final shape. The first is called vacuum forming, which uses negative pressure to draw the warm plastic into a mold.
Pressure forming is also possible using positive energy. Vacuum processes are limited by physics, but positive pressure reaches higher levels, making it a more versatile choice. In order to avoid thin spots, the sheets undergo pre-stretching. Once in place, the trapped air escapes via vents in the mold, and the cooled product is then ready to trim.
Some thermoplastic processes require molds with both positive and negative sides. The warm plastic is positioned between the two, and after appropriate pressure has been applied, the material assumes the size, shape, and detailing of the interior space. While this affords greater control, costs are higher. Regardless of the process chosen, only thermoplastics can be reheated safely.
Thicker gauges are used to make vehicle parts, medical industry accessories, electronic component housings, and are even important in some bathroom fixtures. Thinner gauges are perfect for packaging foods, cosmetic products, and numerous other small items such as screws or paper clips. While most are not biodegradable, methods of disposal and recycling are improving.
About the Author:
Genevive B. Mata has over 20 years of professional sales experience, 10 of them directly in the plastic pallets and materials handling industry. On her spare time she works on applied-sustainability projects. If you are interested in plastic pallets price, she suggests you check out her friends PTM.
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