WORKING PRINCIPLE
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Operating principle in this ovens
is a combination of a perforated drum with a large centrifugal fan. The fan
draws the air out of the drum interior, the air passes over the heating
system and it is forced back to the drum. This generates a vacuum inside the
drum by which the material is held on the drum surface. At the same time the
material is penetrated by large volume of the air which ensures high heat
transfer. |
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Air is
sucked from the center of the drum………………………… |
Felt comes in intimated contact with the drying
medium, guaranteeing high efficiency and optimum capacity. |
and then delivered to the surface. |
The flow trough principle is the basis of for a good air permeability and breathing activity and it produce
high quality web with soft textile handle.
To prevent perforation marks on delicate material, drum is covered
with extra fine belt that carry the web from the foulard and transport it out
of the oven.
To prevent felt shrinking on specifi
material, as option, drum could be equipped with two needled bars, installed at
the border of the drum, manually set at different thickness.
Drum
driers are equipped with high-pressure & vacuum fans which force a large
volume of the air trough the material, even trough felts with heavy weights. By
installing infinitely variable speed motor on the fan, the line performance can
be adapted to material qualities with different air permeability.
Heating via gas burner give a reduce warming up and
cooling time, high efficiency and accurate temperature regulation due to the
flame modulating system, driven with PID controlling device. Part of the finish
fumes and gases are combusted which result of less air pollution.
Due to the full passing of the air throughout the
woven, these ovens are extremely efficient, and need reduced floor space. The
drums diameter are optimized accordingly with the speed and the application, and they can vary from 1
to 4 meters. Speed up to 200 mt\min. Possibility of
adding more than one drum in line to achieve faster speed. When the felt is
narrower than the width of the drum, two internal flaps close the passage of
the air inside the drum itself, out of the felt. This to avoid loss of
efficiency due to air flow that does not passes throughout the felt.
The typical application of these ovens are :
- Drying of
foam bonded nonwovens (or liquid bonded),
- Thermal
stabilization of technical
needled felt,
- Drying of
foam printed webs,
- Drying of water
entangled webs.
Big
perforated Drum, for high speed production (Up to 200
m\min) Diam 3,6 m. Width 4 m
Complete
line for chemical bonding of felt Felt is impregnated
with foulard and then is dried with the drum drier. -
Heating with thermal oil. -
Diameter 2 meter. - Widht 2,5 mt. After
the oven a smoothing calender improves the
surfaces of the felt.
Double drums ovens for felt drying. Diameter 3 meters, width 3,6 m, warmed
with gas burners Application : Roofing felt. The line includes an heat setting oven, foam applicator and calender.
Heat setting oven, equipped with No. 2 rounds of pins in order to keep
the felt during the heat-treatment. Temperature : 225 °C. At the oven
entry, there is one opening frame, with chains and pins, to increase the
felt width. The width is then fixed into the oven, by the two rounds with
pins.
High
speed line for light webs (15-50 gsm) The webs are
calendared, foam bonded, dried, and rolled up. Width 3,6 m