For over 50 years, elm-plastic GmbH in Dudeldorf/Germany has stood for
high-quality, technically sophisticated articles in plastic. With some 100
employees, this mouldmaking and injection moulding company in the Eifel
region produces primarily injection moulded parts for the pharmaceutical
industry. An existing 500 kN injection moulding machine was to be used for a
small DIY-store article. The perfect solution with an optimum opening stroke
was provided by the new Streamrunner, with an additive-manufactured
manifold block, from HASCO, the Lüdenscheid/Germany-based standard
component and hot runner specialist.
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Even though elm-plastic’s product range mainly comprises pharmaceutical primary
packaging materials and dosage aids for human and veterinary preparations, the
company repeatedly works on projects from different areas. These include a product
with a highly demanding geometry that is to be sold in DIY stores in future. The
HDPE injection moulding is produced on an 8-cavity mould. “The customer calls off
batch sizes of 400,000 articles several times a year,” explains Roman Möhs,
development manager at elm-plastic. The geometry of the article posed a particular
challenge, however. “Our 500 kN injection moulding machine is actually ideally
suited to this article with its 8-cavity production,” explains Möhs, “but the permitted
installation height is somewhat tight for the application. We had to find a different
solution, because switching to the next largest 750 kN machine was not a real
alternative.
Streamrunner – Compact 3D-printed HASCO hot runner system
The in-house mouldmaking department at elm-plastic, which produces some five to
ten moulds itself each year, relies on standard components and hot runner
technology from HASCO. Roman Möhs looks back to the last K – the world’s
leading trade fair for the plastics and rubber industry in Düsseldorf – where the
HASCO specialists presented a new development. “The new Streamrunner has
indeed made it possible to save 10 mm on the mould thickness for this project,
despite the complex installation situation and the demanding gating,” explains
Stephan Hatarik, a technical sales engineer at HASCO hot runner. Since the
manifold block, which is available on the market exclusively from HASCO, is
manufactured in an additive laser sintering process, the complete “hot half” can be
produced much more compactly. “This gives us the necessary space for the
opening stroke to ensure reliable demoulding,” says Möhs, “and we also have a
certain reserve when it comes to the installation height and ejector stroke, etc.” This
would have been almost impossible with a conventional standard hot runner, the
development manager stresses. “And 10 mm is really a lot for a cylindrical article
with a length of 25 mm,” he adds.
A further key advantage of the 3D-printed manifold is that the flow channels can be
freely designed to suit the precise requirements, thus ensuring an optimally
balanced design with radii everywhere and hence no dead corners. The additive
manufacture of the hot runner employing the 3D laser sintering process enables the
complete manifold block, including all the threads, to be manufactured in one piece
in a single operation. “No deflection elements have to be shrunk in, which could then
leak,” Stephan Hatarik explains. In addition, 3D printing permits very close hole
spacing and highly variable nozzle configurations.
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Small but very complex DIY-store article
It became clear during the 3D design process for the mould already that the space
problem could be solved with the aid of the 3D-printed manifold. The demanding
gate for the relatively small, complex article prompted HASCO to additionally
conduct a Moldex filling simulation, or flow analysis – a service that HASCO
generally offers its customers free of charge. This simulation resulted in the gating
point being moved by a number of millimetres prior to the manufacture of the mould
so as to avoid air inclusions.
Roman Möhs was pleased that the delivery time for the individually designed and
manufactured 8-cavity Streamrunner with its modified screw-in 20 mm Techni Shot
nozzles was only slightly longer. “We can easily recover the slightly higher costs by
using the smaller machine.” He was delighted about the HASCO innovations, which
enabled the entire project to be carried out and handled without any problems. The
fact that the nozzle tips and the heating can be installed from the parting plane also
proved to be a great help, since this facilitates maintenance.
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The mould has moving parts on the ejector side. The DLC (Diamond-Like Carbon)
coating on the slideways reduces the coefficients of friction and permits a
considerably longer mould life without separate lubrication.
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Even though the current project is an article for DIY stores, the absence of
lubrication is important for elm-plastic because the machines are operated primarily
in a clean-room environment for the production of medical devices. All the injection
moulding machines at elm-plastics have all-electric drives.
Faring well in the crisis with medical devices
Since elm-plastic produces mainly products for eminent international pharmacists
and contract fillers working for the pharmaceutical industry, the Eifel-based
company has not suffered any significant loss of sales during the corona crisis.
“Our product range primarily comprises pharmaceutical packaging materials and
dosage aids for human and veterinary preparations. Apart from disposable syringes,
this also includes products such as pipettes, applicators and injectors in a wide
range of designs, dosage aids, perforated screw caps, pipette wipers and a great
deal more,” explains Roman Möhs.
During the corona crisis, additional orders have been received, even from the USA,
for items including measuring beakers and a wide variety of pipettes.
The positive experience obtained with these projects is the reason for elm-plastic “to
continue working together closely with HASCO” says Roman Möhs.
For elm-plastic, is it a huge advantage that all HASCO’s standard components can
be supplied from stock and that replacements are available without any problems in
the event of a failure. “If we order a replacement part in the online shop, it’s there
within 24 hours”. We can’t even produce a replacement part ourselves that quickly,”
adds Roman Möhs. And the restructured hot runner zone in the HASCO online
portal has also had a large amount of information added to it. One feature is the
new, intuitive enquiry form which can be used to request hot runner systems in a
straightforward and time-saving manner.
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With more than 100,000 products, HASCO is a full-range supplier for tool and
mouldmaking and supplies its customers with everything from a single source. A
modular standard-component range, perfectly tailored to customer requirements,
and individual hot runner solutions provide a reliable basis for high-quality moulds
and hence sustainable competitiveness.