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temperature control, barrel cooling in Blow moulding, barrel screw heating and
cooling in extrusion process, for drying in pet crystallization and drying and curing in
rubber industry. Low-watt density heaters are maintained in hot oil units to reduce
the risk of oil charring.
Water Manifolds: Manifolds are key components of mould water cooling circuits.
Their primary function is to route cooling water from the tower or chiller to the water
passages in the mould, then collect the warmer water leaving the mould, at
turbulent flow rates, and return it to the external cooling water loop. When populated
with auxiliary products, such as, ¼ turn ball valves, flow meters, temperature
indicators, and mould temperature regulators, they appear like spiny creatures.
Properly sized manifolds ensure adequate flow of water providing efficient cooling
within the moulds and machine parts.
Heaters & Controls: All plastics required to be heated to a particular temperature
to be processed at acceptable performance levels. This is supplied by electric
heaters. Heating elements are different types of metallic components that can
electrically conduct heat in many products. They are used in various configurations
and are capable of heating particular areas or items directly or indirectly. A wide
array of heating elements and other components are available to meet a
processor's requirements.
a) Band Heaters: 1) Mica insulated band heaters 2) Ceramic insulated band
heaters 3) Aluminium shoe-style band heaters for very large diameter cylinders
4) Mineral - insulated band heaters - very high temperature applications.
b) Cartridge heaters: are tube-shaped, heavy-duty, industrial heating elements,
usually custom manufactured to a specific watt density, based on its intended
application. They provide superior heat transfer with uniform temperature.
They are inserted into moulds, hot runner nozzles and extrusion related
auxiliaries.
c) Coil Heaters: They are also known as high performance tubular heaters or
cable heaters and have better performance but similar construction to
cartridge heaters. Due to their special construction these heaters allow very
high watt densities and usually installed where space available for heating is
limited and are widely used on hot runner nozzles, manifolds, die cast nozzles,
packaging machines
d) Mineral insulated cable heaters : they are coiled and used on hot sprue
bushing / runner less moulding nozzles.
e) Cast-in heaters : typically used in extrusion - related applications.
f) Strip heaters : available in mica-insulated, ceramic insulated and aluminium
shoe varieties. They are commonly used to apply surface heating to dies and
moulds and sometimes acts as a radiant heat source in thermoforming or
plastic bending applications.
g) Radiant heaters : they have the ability to heat a product without physically
contacting the product. Used in non-conductive heat source for thermoforming
and bending-welding applications.
h) Quartz : faced and black body panels are popular as they can be made in broad
range of dimensions.

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