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How are rotational mold cases made?

Stack of gray storage cases.

So many people want to know: How are rotational mold cases made? So, let us break it down for you.

For nearly 50 years, Pelican™ Hardigg™ single lid and double entry rack mount cases have been trusted by the US Military. These rotational mold cases offer 20% more protective material in the edges and corners, due to their unique molding process. Here is a brief overview:

Mold Preparation: Pelican™ has invested in hundreds of mold sizes, in order to provide a large array of size options. The mold is made of metal and consists of two halves that can be assembled and disassembled.

Material Loading: Light weight, high impact polyethylene plastic resin is loaded into the mold.

Mold Heating: The mold is heated and begins to rotate around two perpendicular axes. As it rotates, the plastic inside adheres to the inner surface, melting and forming a layer. This method of rotating during the molding process is what helps force excess material into the corners and key areas of the container, to create its rugged structure.

Coating and Fusion: The molten plastic coats the entire inner surface of the mold, creating a uniform layer. The rotation helps distribute the material evenly, and fusion occurs between the particles.

Cooling: The mold continues to rotate while it is cooled, solidifying the plastic. This ensures a consistent thickness of the final product.

Demolding: Once the plastic has cooled and solidified, the mold is opened, and the rotationally molded product is removed. The excess material is trimmed off, leaving the final case.

Key features of a Pelican™ Hardigg™ roto mold case:

  • One-piece construction, molded from lightweight, high impact polyethylene.
  • Molded-in ribs and corrugations for secure, non-slip stacking, columnar strength, and added protection.
  • Patented molded-in metal inserts for catch and hinge attachment points, which provide strength and spread loads to the container.
  • Positive anti-shear locks, which prevent lid separation after impact, and reduce stress on hardware.
  • Molded-in, tongue-in-groove gasketed parting lines for splash resistance and tight seals, even after impact.
  • Reinforced corners and edges for additional impact protection
  • Recessed hardware for extra protection

Pelican™ uses the rotational molding process to produce durable, impact-resistant cases with complex shapes, making them suitable for a wide range of applications where protection and durability are essential.

Click here to view the entire size list of Pelican™ Hardigg™ single lid cases. Click here to view the entire list of Pelican™ Hardigg™ double entry rack mount cases.

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