Rotomolding, or rotational molding, is a manufacturing process in which a measured amount of plastic resin is loaded into a mold, heated, and the mold is spun on at least one axis until the hot, fluidized resin acquires the shape of the mold. At that point the mold is cooled and despun, and the finished part is removed from the mold. The mold can be used again for the next part.

  The resulting part has a number of useful and interesting properties. A greater amount of resin collects in corners and joints, where stresses may naturally be higher. This leads to a rugged, durable, seamless part requiring no assembly or bonding. The color will never crack or chip, since the resin can be colored before being loaded into the mold. It is possible to make the resin result in a 'marble' or 'woodgrain' finish on the part. The resulting part is corrosion-proof. The resins can be tailor-made to suit regulatory requirements, such as FDA regulations. The process is economical for both large- and small-volume production runs. In many cases, rotomolding can yield parts too complex or topologically difficult to mold by other conventional molding methods, such as injection molding. Also, since with rotomolding the molds do not have to withstand increased pressures of injection molding or blowmolding, they can be structurally thinner and cheaper.

  Rotomolding is used to produce a wide variety of commercial products. Among them are:
  
  • Plastic whitewater kayaks
  •   
  • Playground equipment
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  • Vending machines
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  • Highway barriers
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  • Headrests
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  • Air ducts

  • And much, much more...