AND PRESSING SECTION
After trimming and the start given by the worker, ensembled
panel goes at the entry of heating and pressing section, where glass
thickness is checked; panel comes to first oven and to first press,
then comes to the second oven and to the second press for the final
working step. After the unloading through exit tilting table, panels
were put in the specific trolleys (not included in the supply), that
will entry in autoclave to make the needed cycle.
FEATURES AND TECHNICAL DETAILS:
Heating process through special infrared medium wave
lamps, with quartz frame and golden reflecting surface on back side.
- First oven length 2 mt, with 6 lamps (3 on top and 3 on bottom); second
oven length 4 mt, with 18 lamps (9 lamps on top and 9 on bottom); to increase
productivity (+15%), 8 lamps on first oven and 24 on second oven can be
mounted (OPTIONAL); high speed heating and pressing version (+50% productivity),
first oven length 2 mt with 10 lamps, second oven length 6 mt (3 sections
of 2 mt) with 30 lamps.
Each of two ovens is controlled separately by PLC, with
temperature, irradiation control system and glass presence system, to
optimise working phases and the saving of energy; specific software
for small glass.
Temperature reachs needed values through PID, with fastest
speed and lowest consumptions; the choke system of the power, and switching
on/off of the lamps independently (for each pair), enables the processing
of special glass types (low-e. glass) for a more flexible production
Suction system of the ovens with fans, to fall temperature
inside ovens, if it's too hot.
Forced air convection system inside ovens (OPTIONAL),
that keeps the same temperature inside the whole volume of the ovens through
canalized hot air flow (carry out by closed circuit and two fans one on
the top and one on the bottom); this device is very useful to heat PVB
film working big thickness (more than 60 mm) and with glass that was treated
on one side (Low-E, reflective, painted glass
); air heating through
IR (infrared) lamps; hybrid furnaces can work with air convection system
or only with infrared heating; this double way to work guarantees energy
saving (thanks to the air convection processing) and big flexibility for
mixing production (thanks to the fast adjusting speed of the infrared
heating when it needs to change production values, processing different
kinds of glasses).
Rolls inside heating section have diameter 113 mm (studied
to bear the weight of jumbo sheets) and are covered by "Kevlar"
plait with big thickness to avoid speedy wear and tear.
To facilitate maintenance, ovens have the top part that
can be lifted by bridge crane and repositioned through specific rails.
Temperature inside heating section is checked by specific
thermocouples, three for first oven, 6 for second (9 if oven has length
Temperature glass panel check at the exit of first oven
and at the exit of second press, through pyrometer; this is a very useful
indirect control, to verify that inserted parameters are correct, according
to different glass and PVB sizes and kind.
Heating section total installed power: from 120 to 200
Kw (according to total number of lamps).
Press is constituted by rolls, stainless steel made,
covered by special rubber; rolls are planned expressly for this working,
to avoid the forming of air bubbles between glass panel and PVB film;
perfect pressing of any type of glass and any size thanks to the anti-torsion
system that applies a uniform pressure on all the length of the presses;
it is, therefore, not necessary to position small glass sheets centrally;
Top rolls of mangles adjust automatically according to
ensembled glass panel thickness (checked at the entry of first oven) through
motors and screws system; the rotation of top and down rolls is regulated
by only one motor that gives the motion at the same time through gearing
system; pneumatic cylinders (two for each press) regulate the pressing
power; rolls pressing is optimised and gauged separately through PLC.
Mangles (pressing rolls) with diameter 400 mm, covered
rubber with hardness 85 Sh.
- Total pressing power for each mangle: 21.040 N (value at 6 bar).
- Motor of first press drives transport rollers of first oven, motor of
second press drives transport rollers of second oven.
Heating and pressing process is made easy by the presence
of several predefined formulas.
COSTRUZIONE MACCHINE ITALIA S.R.L.
VIA AQUILEIA 14
31048 OLMI DI S. BIAGIO DI
P. IVA 03289430260
TEL +39 0422 794111 FAX +39