Sfogliabile_A&L_n4_AGOSTO_2016

0056-0063 8
novative patented Adaptive Modular Cooling system that
employs high intensity multi-fuel air-water nozzles to control
extruded profile cooling downstream of the press.
Through fine and differential control of the two fluids the
surfaceheattransfercoefficientcan
bemodulatedrepetitivelythrougha
widespam,rangingfromair-onlyup
to water-only cooling system.
Water drop size and dynamics control
using mixture of air allows to eliminate
the Leidnefrost effect, i.e. the insulation
of the surface by a layer of steam
which partially jeopardize thermal exchange,
obliging to increase the water
spray dynamics: this means that
cooling using water-only nozzles is
limited to high heat exchange coefficients
leading to severe distortions
and residual stress in the treated profile,
especially where a complex geometry
is involved.
The regulation of the flow of water
and air is carried out separately
for each longitudinal module and
allows to accurately control the entire
HTC cooling curve. The air and
watercanalsobeadjustedwithsix
the 6082 alloy, where typically a cooling speed above
50°C/s is required.
The mechanical design with concealed pivoting covers offers
a significant reduction in overall dimensions above the roller
Figure 8:
Cooling curve
for automotive
profiles obtained
using modular airmist
control
Figura 8:
Curve di
raffreddamento
per profilo
automotive,
ottenute con
controllo air-mist
modulare
different cross-sectional modulations in order to balance
the cooling of asymmetric profiles and to minimize
deformation that make the subsequent profile handling
problematic.
Water lines are individually fed by variable speed pumps,
similarly, air is provided by two dedicated compressors
which are also controlled by variable speed motors
These systems are based on the most recent developments
in terms of energy savings and plant simplicity.
Figure 8 gives an example of cooling curves obtainable
during the cooling process of a ”crash box” profile in
table and gives the operator full access
when the tunnel is open. Deletion of the
traditional upper cooling hood including
the support and movement systems
permitsrealisationofapullerwithupperrailsandfurtherincreasessideaccess
functionality for the operator.
The tunnel adjusts the height and inclination
angle according to the dimensionsoftheprofiletoensureanequal
distance between the upper and lower
nozzle profiles.
The ability to integrate extrusion with
the control of thermal processes upstream
to downstream of the press is
nowanabsolutenecessityinorderto
offeraflexibleandreliableresponseto
the strict quality requirements of the
aluminum profile, in particular where
high strength applications are concerned.
Tools recently developed by Danieli Breda exploiting the potential
of the prestigious research center and the wealth of
expertise of the Danieli group, allow any extruder to extend
possibilitiesforproductionandaccessandnewmarketsin
this rapidly expanding sector.
Specific requirements of each individual producer are analyzed
in detail, defining the most appropriate solution for
each specific production, complementing existing plant
equipment in order to obtain maximum benefits with minimum
investments.
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August 2016 N° 04
- 63