Roto Moulding Services

Rotational Moulding, or roto moulding as it is commonly known is an extremely versatile, relatively cost-effective method of producing hollow plastic components. The process is ideal for the manufacture of simple or complex shapes and because wall thicknesses can be accurately controlled the process lends itself very well to a wide variety of applications ranging from simple products such as safety steps and grit bins to more complex products such as children’s slides, hairdressing furniture and even missile cases.

What is Rotational Moulding?

Rotational moulding, as the name suggests, involves a tool being rotated in an oven whilst being heated and then cooled over a cycle time of approximately 45 minutes to 1 hour.

Polyethylene powder (shot weight) is measured out by the operator and placed into the tool which is manufactured from sheet steel, cast aluminium or CNC aluminium depending on the product design and complexity (see our tooling section for further information). The tool is then clamped shut and moved into the oven chamber. The chamber is heated up to around 220°C to 350°C and the tool rotates on two axes at low speed. As the tool heats up the polymer melts and begins to adhere to the inner surface of the tool until it has completely melted. Once the cook part of the cycle is complete the product is then cooled before it can be removed from the tool. The end product is a hollow, virtually seam free shape with a consistently even wall thickness.

Depending on the product it may be necessary for us to use a cooling jig immediately after the product is removed from the tool. A cooling jig is essentially a frame that is specifically designed to hold the product in order to stop it from shrinking or expanding in order to ensure that the product is dimensionally correct once it has finished cooling. All rotational mouldings are subject to varying degrees of shrinkage once removed from the tool, for some products this may not be a problem but for on others where dimensions are critical, a jig will almost certainly be required. Generally, we advise customers that shrinkage of approximately 1% to 2% is normal for any polyethylene product so this is something to bear in mind at the design stage.

For a brief overview of the process why not check out our new video!

  • Why Choose Rotational Moulding?
  • Advantages Of Rotational Moulding
  • What You Can Expect From Your Products And Tooling?
  • What We Need To Get Started With Your Project

Materials

We work exclusively with LLDPE polyethylene which is sourced from 4 main UK suppliers. We stock 12 standard colours however if a customer wants something bespoke for their project our suppliers are usually able to colour match to a RAL or Pantone reference. The cost increases due to it being a non-standard colour but generally it is always possible to do.

Read More

Product Finishes

There are lots of available options with roto moulded products, some of which are shown below. We do not have a design team so if assistance is required in developing a design we can help by recommending companies to work with who have an excellent knowledge of roto moulding. We are happy to be involved in that process to ensure that your final design is achievable, and even if it isn’t we will always help to

Read More

Inserts

Inserts - metal inserts are very common in rotational moulding and we have many customers’ own products featuring all manner of inserts as pictured below.

Read More

Gallery

Recent Case Studies

Scottish Salmon

Scottish Salmon

We were recently delighted to win a contract with the Scottish Salmon Company, a fully integrated salmon farming business, and […]

Read More
Linemark

Linemark

Linemark is a successful sports and amenity paint manufacturer, supplying line marking paints, machines and accessories in the UK and […]

Read More

We would love to hear from you if you have a contract rotational moulding project in mind

Make An Enquiry