Technology
QUALITY | ROTATIONAL MOULDING
Rotational moulding offers a great deal of freedom in design and has fewer restrictions than other processes used for the manufacture of plastic parts. It can be used to produce open or closed items with dimensions that can start from diameters as small as 25-50 mm. The shapes can be simple (spheres, containers) or complex (fuel tanks, automotive components). Parts can be moulded with thicknesses starting from 1.0 mm up to 50mm. The parts may be coloured or transparent, flexible or rigid. Rotational moulding is suitable for small production runs, but it can be used for the production of 50,000 – 100,000 parts/year. Above these values a more automated process should be considered. However, in cases where the rotational moulding is the only viable process, higher production outputs can be obtained using multiple moulds and machines.
COLOUR
Polyethylene is by far the most common material used in rotational moulding, but it has traditionally suffered from the disadvantage that it cannot be reliably painted. The same difficulty applied to polypropylene. Although these polymers can be coloured using a tinted raw material, good control of final appearance has been impossible, precluding their use in very many applications. Now tecni-industry have solved the problem. You can now have any of the following paint schemes on polyethylene and polypropylene rotomouldings:
- High gloss solid colour, pearlescent or metallic finish applied to smooth surfaced mouldings
- Textured satin finish applied to smooth surfaced mouldings
- Soft touch satin finish applied to smooth surfaced mouldings
- High gloss solid colour, pearlescent or metallic fisnish applied to textured mouldings.