Rotational Moulding
Rotational moulding is a highly versatile manufacturing process that allows for virtually unlimited design possibilities, and offers design advantages over other moulding processes; parts that are usually assembled from several pieces can be moulded as one part. This reduces fabrication and assembly costs.
The process also has a number of inherent design strengths, such as consistent wall thickness and strong outside corners that are virtually stress-free.
Designers can select the best material for their application, including materials that meet FDA requirements. The process allows for multi-wall molding that can be either hollow or foam filled for increased strength or insulation properties.
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Cost advantages
Rotational molding is very cost-effective when compared to injection and blow molding for both small and large parts.
Production costs for product conversions are reduced because lightweight plastics replace heavier, often more costly materials. This makes rotational molding as cost effective for individual prototypes as for large production runs.
The rotational molding process
The rotational molding process is divided into 4 steps:
| 1. Loading |
2. Heating |
3. Cooling |
4. De-molding |
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A mold is mounted on a mold carrier and charged with plastic powder. |
Under biaxial rotation the mold is heated until the powder is properly molten and forms a uniform layer on the inside of the mold. |
Under continued rotation the mold is cooled until the melt is frozen. |
The mold is opened and the final product is removed from the mold. |