Most plastics are derived from oil, natural gas, and some plant materials. Although plastic products have been called the ultimate symbol of a throwaway consumer society, everyone uses them. Even the most ardent critics express their concerns via plastic computer keyboards. Thermoforming is a manufacturing process that shapes this raw material into finished products.
Environmental concerns regarding fossil fuel dependence are real, but plastic production accounts for less than 3% of the total amount of natural gas and oil consumed in the United States. While that is still a considerable amount, eliminating all production would do little or nothing to diminish reliance on oil as a fuel source, and would probably increase overall consumer prices.
The process begins by turning raw hydrocarbons into sheets of acrylic, polyvinyl chloride, polypropylene or other chemically similar polymers. They arrive on site in varying thicknesses, and are warmed until they become malleable, but not runny. Employing one of the three most common methods of production, the warm material is then molded, cooled, and the excess cut away. The result is a durable component.
During production, radiant electric devices five inches from the sheet produce heat. The amount of time plastic takes to become malleable is determined by the variety of polymer, and there are three methods that are most commonly used during molding. Vacuum forming uses principles similar to an everyday vacuum cleaner, sucking the warm plastic into a mold with carefully measured force.
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 sheets are used to make different vehicle components, are molded into health care accessories, and even make an appearance in the bathroom. Thinner gauge plastic sheeting is used to package cosmetics, small individual products like screws, and fresh and processed foods. While not yet biodegradable, recycling and disposal methods have been greatly improved.
Environmental concerns regarding fossil fuel dependence are real, but plastic production accounts for less than 3% of the total amount of natural gas and oil consumed in the United States. While that is still a considerable amount, eliminating all production would do little or nothing to diminish reliance on oil as a fuel source, and would probably increase overall consumer prices.
The process begins by turning raw hydrocarbons into sheets of acrylic, polyvinyl chloride, polypropylene or other chemically similar polymers. They arrive on site in varying thicknesses, and are warmed until they become malleable, but not runny. Employing one of the three most common methods of production, the warm material is then molded, cooled, and the excess cut away. The result is a durable component.
During production, radiant electric devices five inches from the sheet produce heat. The amount of time plastic takes to become malleable is determined by the variety of polymer, and there are three methods that are most commonly used during molding. Vacuum forming uses principles similar to an everyday vacuum cleaner, sucking the warm plastic into a mold with carefully measured force.
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 sheets are used to make different vehicle components, are molded into health care accessories, and even make an appearance in the bathroom. Thinner gauge plastic sheeting is used to package cosmetics, small individual products like screws, and fresh and processed foods. While not yet biodegradable, recycling and disposal methods have been greatly improved.
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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