CONNECTORS & FITTINGS
THERMOSET
HARTING
REDUCE DOWNTIME AND PROCESS COSTS FOR
THERMOSET PLASTICS INJECTION MOULDING
The applications and uses for thermosetting
plastics have grown substantially over recent
years. The benefits of this type of plastic are
largely due to its favourable plastic properties.
Thermoset plastic polymers cross-link
together when being cured and so form
an irreversible chemical bond. Along with
thermoplastic, this is one of only two organic,
polymer-based plastic materials.
THERMOSET: THE MATERIAL FOR
EXTREME SITUATIONS
Closed-meshed, cross-linked thermoset
molecules require a completely different
temperature profile to thermoplastics. The
compound is injected from a cold cylinder
module into a hot mould.
Further heating and melting of the
compound in the mould causes a decrease in
viscosity that is only reversed when cross-
linking increases. The finished component is
then irreversibly cross-linked, which makes it
extremely hard.
The temperature reached within a thermoset
injection mould tool is significantly higher
than a thermoplastic version. As such,
the electrical connectors that are surface
mounted to the tools, and carry the
temperature monitoring thermocouple
contacts, will experience temperatures of
30 to 40 degrees C higher than the typical
standard connector working temperature of
125-degree C. As a result, there is a tendency
that these connectors will have a reduced
operating life.
These potential connectivity component
failures can occur during the plastic
component assembly process, which means
critical mould temperatures will cease to
be controlled. Consequently, in some high
volume production conditions, parts may
come off the line which do not meet quality
standards, resulting in increased and costly
waste materials.
HARTING has recently launched a new
high temperature version of its Han series
multipole connectors that addresses these
issues through its extended maximum
working temperature capability. This
significantly extends the operational lifetime
of the thermoset plastic injection mould tools,
reducing potential tooling maintenance and
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PECM Issue 37
service periods, line downtime and ultimately,
operating costs. separately applied, detrimental protective
coating finish.
HARTING has used its considerable technical
expertise to develop special connectors
which provide reliable solutions for these
high-temperature environments. The connector insert and contacts must
withstand the high ambient conditions of the
location and the additional heat generated
inside the housing when under mated load.
HARTING has selected high-temperature-
resistant copper alloy contacts that maintain
constant electrical properties when heated.
In addition the high-temperature LCP plastic
inserts ensure a longer service life.
For example, bulkhead connector seals
must not melt or adhere to other integrated
component parts over the full operating
temperature range. Consequently, HARTING
has opted for a non-stick coated high-
temperature-resistant rubber version, which
avoids bonding between the hood and
housing even if they are left mated for several
years.
Many of the hoods and housing coatings
and lacquers available on the market are
not suitable for long-term use at high
temperatures as they can cause melting,
which can lead to mated parts sticking
together. Thanks to the application of a
special surface treatment to the aluminium
die-cast hoods and housings, HARTING has
been able to dispense with any additional,
As a result of these features, HARTING’s Han®
High Temp connectors can permanently
withstand operating ambient conditions
of +200°C, providing extended operating
lifetimes and ensuring reduced line
downtime, compared to competitor solutions.
*Article reference source: https://www.
osborneindustries.com/news/thermosetting-
plastic-uses-applications/
For further information visit
www.harting.com/UK/en-gb