The project aims to further develop and optimise a moulding
technology for large products with low specific weight and
high strength demands. The developed technology will be
used to establish an enterprise which will initially
produce large pallets for the food industry. This pallet
has to fulfil the following demands:
- it has to satisfy the ISO 8611 standard, and other
requirements that this industry has (e.g. hygiene
- it has to be designed for long life, low specific weight
and be easy to handle
- it has to be economically competitive, compared to
This implies taking up several design and production
challenges such as:
- low weight, but at the same time strong requirements
with respect to stability and strength
- no internal cavities (any cavities have to be foam-
filled). Currently thick foam walls (about 50mm)
are a problem.
- no "pockets" on the external part (to facilitate
- The product will have variable (partly large) wall
thickness. This is problematic with injection moulding.
It is planned to solve these challenges through the use of
low pressure, multi-moulding injection. One of the main
challenges will be to include foaming in the process, and
at the same time achieve a high strength product.
Some of the concrete work tasks in the project will be:
- define the optimum plastic material which in addition is
approved by the food industry
- develop the optimum production technology to develop a
strong enough product
- technical development of mould design
- develop and construct machine technology to produce both
1/1 and 1/2 pallets
- come up with a method to fill internal cavities with a
material with the lowest possible specific weight (from
the same family of plastics), which at the same time
ensures joined cells. When combining plastic materials
there will be problems with the attachment between
materials, and how this develops with cyclic loads.
Plastic materials will also shrink with ageing, but
the degree of shrinking varies from one material to
- mechanical properties of parts inside the pallet have
to be seen in connection with the demands on the pallet.
In particular with foam enclosures the properties also
have to be evaluated in connection with loads during
the injection moulding.
- FEM (finite element method) analysis is necessary to
analyse the properties of a pallet with loads. It is
important to estimate the effect the dimensions of
different components in the pallet will have on the
properties of the pallet.
- develop and test prototypes
- produce O-series.
All these tasks are planned to be carried out within the
Keywords: plastic, moulding, pallets.