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the ground product, while improving the life of the granulator,
as worn pieces can be replaced.
Another distinctive feature of Piovan granulators is the possi-
bility for customisation. Even the most basic versions can be
modified to suit the specific needs of the process (e.g. blow
moulding, extrusion, injection) and to comply with specific
customer requests in terms of space, granulator loading and
unloading requirements and protection of the operating envi-
ronment - these machines also guarantee extremely low noise
levels.
N35-60: the state-of-the-art granulator
At Fakuma 2015, Piovan presented the N35-60, a machine en-
compassing all of the characteristics described above, in addi-
tion to featuring a 90° adjustable hopper for 4 loading
positions, ensuring that if fed by conveyor belt, the direction
of the belt can always suit the granulator hopper inlet. Main-
tenance is therefore simplified and less operating space is re-
quired.
Fast access to the machine is another important factor, given
that in certain operating conditions cleaning operations may
be necessary on a daily basis. This feature is a response to a
specific request by numerous users who need to insert the
granulators at the end of production lines where space is often
limited.
N35-60 is part of a family of three granulators designed specif-
ically to process large pieces or such as injection moulded food
containers, large bottles or cans (blow moulding), tanks, bins,
gardening products, toys (rotational moulding process). These
objects are normally quite large and light and can therefore
bounce and be difficult to cut.
Single-shaft shredders:
the complementarity of a product
Complementing the range of granulators
is the single-shaft shredder line, perfect for
recovering purgings from start-ups or ma-
terial replacements during all transforma-
tion processes. To make an example, if we
consider a facility with 200 moulded items,
equipped with 30 presses: in one year they
may need to change moulds 600 times,
each time the injection unit needs to be
purged. The weight of an average purging
(from 2 to 4 kilos) multiplied by the number
of mould changes, produces numerous
tonnes of engineering polymers that can
be recovered with a shredder.
Shredders are machines whose role par-
tially overlaps that of granulators and
sometimes even integrates their function.
At times, to granulate and recover medium
to large-sized waste, it may be more con-
venient to use a shredder rather than a
large-sized granulator. Granulated waste
can then be ground by smaller and more
economical granulators.
With the same-sized parts, a shredder uses much smaller mo-
tors compared to a granulator, which translates into signifi-
cant energy savings in cases where high throughput is not
necessary.
The Piovan range of single-shaft shredders includes 4 different
models, each with a hopper that can vary in size from 600x600
mm to 1500x1500 mm.
Piovan recycling line: excellent results using less energy
We've already meantioned that one of the advantages of a
tangential cut, with the same size parts, allows us to use much
smaller motors.
Piovan granulators are also fitted with energy efficient electri-
cal and control systems: the entire transmission system has in
fact been revised to achieve effective energy savings when
used 24/7. Even if the granulator doesn’t work continuously,
it is possible to optimise peak loads to reduce energy con-
sumption.
For example, in the case of blow moulding, the granulator is
used heavily at start-up, while during operation it is used in-
termittently to grind 20-30% of production. Between one
mould and another there are a series of idle periods in which
the granulator is inoperative, even if the motor remains on.
The energy saving system intervenes in this case to manage
the idle periods and optimise consumption.
The new range of Piovan high-efficiency granulators guaran-
tees energy savings between 15% and 35% depending on
the application.
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