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How it Works

Hollow molds are filled with resin. The molds are then put in a large oven and rotate slowly to allow the material to evenly disperse and melt on to the mold surface. Then the mold goes into a cooling process, which helps to harden and set the plastic material.

How Rotational Molding Works

Depending on the part size, single or multiple molds are placed on the arms of the machines. Pre-measured granulated plastic resin is loaded into each mold, which is then closed. The arm with the molds is then indexed into the oven where they are slowly rotated on both the vertical and horizontal axis.Utilizing heat and continuous multi-axis rotation the powder melts against the inside of the mold, forming a hollow seamless part with an even wall thickness.

The molds are then indexed to a cooling stage where the continue the multi-axis rotation until they are cool enough to remove from the part from the mold. The rotational speed, heating and cooling times are all controlled throughout the process to suit your specific product needs.


Advantages of Rotomolding

Rotational molds costs are very low compared to other type of molding. The process has very little waste, and scrap or excess material can often be re-used, making it an economical and eco-friendly manufacturing process.

Material Processing

Unlike many smaller rotational molders, Agri-Plastics Custom Rotomolding has sufficient volumes of material to allow us to commit to the much superior method of melt compounding our coloured polyethylene. When dry mixing pigments into polyethylene, the pigment acts as a foreign body, significantly decreasing the physical properties of the material. Melt compounding creates a more homogeneous blend and allows physical properties, such as impact resistance, to be far greater. This is very important to most OEM customers, as well as for any product that might receive impacts through normal use.

Melt compounding also allows for richer and more consistent colors. In addition, we have the ability to add fire retardants, ultra-violet light absorbers, anti-statics and many other additives. Another benefit of having higher material volumes is that we pulverize our own material. This allows us to create and meet a quality standard that actually enhances the physical properties of the material and therefore the final product.

In-House Color Compounding

We can make your product any color you want. Our on-site color compounding allows for greater customization.

In-House Dry-Blending

Dry color blending is an another option that helps eliminate production steps, thereby reducing costs and production time.

In-House Pulverizing

On-site pulverizing allow us to create the highest quality resin powder, helps with the speed of production, and lowers the overhead costs to the customer.

In-House Recycling

We recycle all of our scrap plastic. This allows for greater savings for us, and we can pass those savings on to you!

In-House Extrusion

With a large in-house extruder, we can enhance resins with additives such as opacity fillers and color.

Powder-Dispensing System

Our state-of-the-art powder dispensing system accurately and quickly dispenses the right amount of powder for consistent wall thickness.