What are the Main Parameters for Setting Up Rotomolding Process?

What are the Main Parameters for Setting Up Rotomolding Process?

Critical process parameters are operating parameters that are considered essential to maintaining product output within specified quality target guidelines. For rotomolding process, the main process parameters are oven temperature, rotation speed and pattern, cooling time, material drying, and mold design. The above settings determine the mechanical properties and dimensional quality of the rotomolded products.

1. Oven Temperature

The oven temperature is one of the most critical parameters in the rotational molding process. It determines the melting point of the plastic powder and the final properties of the product. The temperature should be set based on the type of polymer used, the desired product properties, and the size and thickness of the mold. Generally, the oven temperature ranges from 300°C to 350°C for polyethylene and from 250°C to 300°C for polypropylene.

2. Rotation Speed and Pattern

The rotation speed and pattern affect the distribution of the melted plastic on the mold's walls. A proper rotation speed and pattern ensure uniform thickness and minimize any potential defects in the final product. The rotation speed can vary depending on the size and shape of the mold, but it typically ranges from 8 to 12 revolutions per minute. The pattern should be adjusted to ensure that the melted plastic covers the entire mold surface evenly.

3. Cooling Time

The cooling time is essential to ensure that the plastic solidifies completely and maintains its desired properties. The cooling time depends on the type of polymer used, the mold size, and the oven temperature. Generally, the cooling time ranges from 10 to 30 minutes. It is crucial to monitor the cooling process to prevent any warping or deformation of the product.

4. Material Drying

Moisture content in the plastic powder can affect the quality of the final product. Therefore, it is essential to dry the plastic powder before the rotomolding process. The drying temperature and time depend on the type of polymer used. Typically, the drying temperature ranges from 80°C to 100°C, and the drying time can vary from 2 to 4 hours.

5. Mold Design

The mold design is crucial for achieving a high-quality product. The mold should be designed with the appropriate wall thickness, draft angles, and parting lines. It should also have a smooth surface finish to ensure the quality of the final product. The mold material should be chosen based on its thermal conductivity, mechanical strength, and resistance to wear and tear.

Light Venus is a professional rotomoling factory with value-added services from design assistant to delivery. To learn more about our custom rotomolding service, please feel free to contact us.