The experience Plastimac Spa has gained by working side by side with several customers allowed, through
Plastiblow co-operation, the development of different solutions to blow technical items, all of them personalized
and destined to various fields. Tailor-made machines are nowadays necessary to penetrate highly specialized
markets, such as the technical products sector. Extrusion blow-moulding technology assumes a more and more
important role in the production of technical articles, due to at least three main factors:
- reduction in the production costs;
- high flexibility of the production process;
- possibility of recycling.
The models working with parison translation are the most interesting for the technical field. In these machines
the parison is carried by pliers from the extrusion head into the mould instead of moving the mould from the
extrusion to the blowing station. The stability of the mould locking unit brings some significant advantages, such
as, for instance, a lower power consumption, the absence of vibration and the remarkable reduction of the dry
cycle time. Furthermore, the particular setting of the mould clamping group makes it possible to place blowing
nozzles in different positions of the mould, and to work with very high moulds. Thanks to these characteristics
the blow-moulding machines using this technology are particularly suitable for the production of long technical
items, i.e. gaiters for shock absorbers and mechanical joints, air or water ducts for conditioning, but also for
production with multi-cavity moulds vertically disposed on the parison axis.
One of the fastest growing sectors of technical blow-moulding is that of thermoplastic elastomers (TPE)
components for the automotive industry where joint coverings and dust covers for shock-absorbers are always
more frequently made of thermoplastic elastomers. Always in the automotive sector we are able to propose
solutions for the making of dust-cover tubes in HDPE or PP.
For producing such products Plastimac offers blow-moulding machines equipped with barrier profile screws and
central feeding extrusion heads. In this way, the plasticization is far more homogenous and the thickness
distribution in the parison is more even. Both results being very difficult to obtain when the ratio between tube
length and diameter is high. Special cutting devices inside the blow-moulding machine permit to finish the item
inside the machine in a very restricted area.
Another interesting field for technical blowing is the white goods sector, the new PB10000/CF blow-moulding
machine, having a clamping force of 18 ton, has been created on that purpose. This machine model is able to
produce, for instance, polypropylene spheres with a diameter of 25 mm by moulds with 28 cavities.
Always thanks to the parison translation technology, we recently made a machine dedicated to the production of
tubes for the building sector. The 5000/CF blow-moulding machine having a 70 mm extruder and cutting system
inside the machine and weighing system in line. With this blow-moulding machine, for a volume up to 5 litres,
clamping force of 10 ton, stroke from 430 to 1100 mm and one-way extrusion head – we may produce tubes
having a length up to 500 mm and diametres of 130 mm.
|
|
