Rotational Moulding FAQs, Applications & Examples

Trifibre is the leading rotomoulding manufacturer in the UK, designing and delivering custom rotational moulding applications for a wide range of clients across many industries.

We’ve made significant investments in our machinery to ensure efficiency and affordability at every step. Our skills and experience allow us to minimise product run time whilst maximising quality, enabling us to provide quality rotomoulding products without unnecessary additional costs.

All rotational moulding applications are completed on site and dispatched from our Leicester factory to customers worldwide.

Since 1981, we’ve worked with the biggest names to provide custom design and manufacturing services using our rotational moulding process. For example, we’ve worked with world leading medical technology company Stryker to create high quality roto moulding healthcare products.

To help our customers better understand the benefits, we’ve compiled a comprehensive guide to how rotational moulding works and its advantages. Read on for more information and examples, or contact Trifibre for a custom rotational moulding quote.

What is rotational moulding?

Rotational moulding is a thermoplastic moulding process that utilises bi-axial rotation and computer controlled machines. The process is split into four operations and can be used to produce a range of robust plastic items, such as large hollow products. It is a popular method of manufacturing plastic products due to the consistent quality it delivers on every unit produced and affordability.

What are the four processes of rotational moulding?

1. Charging

Every rotomoulding application begins with the loading of a hollow, aluminium or steel mould with a pre-determined amount of powdered polymer, typically polyethylene and virgin or recyclable material. The mould is then closed, locked and loaded into an oven chamber or heated by pumping hot oil around channels in the mould.

2. Heating

Once charging is completed, the mould is rotated biaxially (ie. around 2 axes). The temperature of the oven or hot oil channels, typically between 260°C – 370°C depending on the material used, cause the polymer to melt. As the mould rotates, the molten polymer is dispersed evenly and coats the inside walls of the mould.

3. Cooling

After the mould has been rotated sufficiently to spread the molten polymer evenly, it is then removed from the oven and cooled, causing the polymer to solidify.

4. Unloading

When the mould has cooled sufficiently to retain its shape, it is opened and the product removed. The mould can then be reloaded and the rotomoulding process repeated.

What is rotational moulding used for?

A wide range of everyday items are made using the rotational moulding process due to its versatility as a manufacturing process and the advantages it offers.

Rotomoulding products are most prevalent in particular markets such as environmental, construction, engineering and medical. Wheelie-bins and litter bins, car dashboards and cup holders, aeroplane components, cones and road barriers, and children’s toys are just some examples of rotational moulding applications.

At Trifibre, rotational moulding is used to manufacture our exhibition cases and point of sale stands, including products for Salem & Senior Design. The advantages of using rotational moulding for this application is that the resulting products are lightweight, ensuring they can be easily transported, while being strong to protect the contents, which may include roller banners or product samples. We also add hinges, clasps and wheels for greater usability. These cases are a great example of how the rotomoulding process can be utilised to achieve a number of objectives.

Take a look at various components that are used to make the Trifibre Pegasus case a useful piece of kit for exhibitions and events. Contact us for a rotational moulding quote.

What are the advantages of using rotational moulding?

Rotational moulding offers numerous advantages over other plastic moulding methods. It can be used to make a wide range of plastic products that require a rigid and highly resilient finish and is recognised as being a highly versatile and reliable manufacturing process. It reduces internal stresses by providing a consistent finish through an even distribution of materials and eliminates the need for joints.

Strength and resilience

Products that are manufactured using the rotational moulding process do not have seams or joins, so they can withstand more extreme conditions than those made using fabricating, fibre glass, injection, vacuum or blow moulding.


Computer Aided Design (CAD) software is used to create designs that are completely accurate. It helps to streamline the design and manufacturing process and improves the overall quality of the final product.


A key advantage of rotomoulding is that it offers an affordable manufacturing process compared to other plastic moulding methods, as moulds are created using cost-effective materials such as aluminium or steel.

Lightweight products

It is a popular manufacturing process for products that need to be lightweight and user friendly, but also strong enough to withstand external pressure or weight. It’s an ideal solution for making hollow products, such as water containers, kayaks, floats and buoys.


Individual moulds are custom made for each project and can incorporate a range of details, including textured finishes, brand logos, symbols or other lettering.

Limited waste

A significant advantage of rotational moulding is the lack of waste material generated during the production process, as excess material is removed. This undergoes a regrinding process before it is reused for the next application.

What materials are used in rotational moulding?

At the start of the rotational moulding process, metal moulds are created using aluminium or steel, while the final product is made from a range of plastic materials, such as polyethylene, polypropylene, polyvinyl chloride (PVC), nylon or polycarbonate.

At Trifibre, we use a powdered polymer, usually polyethylene and virgin or recyclable materials, to make products using the rotational moulding process. Polyethylene is an ideal material for rotomoulding applications as it does not deteriorate when exposed to extreme heat, enabling it to be easily melted and manipulated into a range of shapes and items.

How does rotational moulding work?

Rotomoulding is a thermoplastic moulding process that involves four key processes: charging, heating, cooling and unloading. It uses bi-axial rotation to provide a clean and even finish to every product. As a largely automated process, rotomoulding can improve production times while producing high quality items.

Computer Aided Design (CAD) software is used during the development process to create accurate product designs and complex shapes. It can also predict how a product may react to external factors, such as extreme temperatures.

At Trifibre, CAD software also enables us to calculate weight and volume for accurate material usage and accurate quotes.

See one of our rotational moulding machines in action.

Contact Trifibre for a rotational moulding quote. Alternatively, find out more about our environmentally friendly packaging solutions or read our FAQs guide to flight cases.