 |
| PET Preform Neck Crystallization System |
 Application
PET Preform Neck Crystallizer
Necessity of Crystallization of PET Preform Neck Finish
Generally, The PET resin begins softening in the temperature of 70 degC
or higher temperature. This softening temperature is so called TG (grass
transition temperature) of PET. Supposing that when PET bottle leaving
in more than 70 degC atmosphere, the bottle neck will start softening and
almost the dimensions will shrink also the deformation of the neck finish
will be occur at the same time.
Specially the demand in the beverage market such as fruit juice, oolong
tea, coffee drinks and lactic acid drinks are expanding in recent years.
However, almost the beverage are filled into the PET bottle at the high
temperature of more than 85 degC, just after that, the PET bottle capped
on the filling line conveyor then, handstand the bottle to sterilize the
inside of neck finish with the high temperature content liquid for some
time.
 Therefore, the neck finish of PET bottle must be withstanding the condition
of the high temperature atmosphere. Normally the state of PET preform neck
finish is amorphous because of it molded by injection molding and that's
why it does not have heat resistant at more than 70 degC. In other words,
this neck finish will have shrinkage of the dimensions and the shape deformation
in the hot filling, and it bring about the fatal defect for PET bottle
such as micro leakage.
But, PET has the characteristic to become heat resistance when it crystallized.
The density of amorphous PET is 1.365 g/cm3, but forget the heat resistant, it becomes the higher density when making
progress the crystallization from 1.365 to 1.380 (crystallinity index 25
% to 39 %).
Our equipment system, which was developed in this time, the crystallization
of the neck finish of PET preform makes progress to get the heat resistant.
System Features
1. At the lading and take out station of the preforms can be operate continuously.
Besides we designed the new mechanism which the devices
does not any inflict
damage of the preforms such as scratch on the surface.
2. The heater unit (lamp unit) was designed by our own unique technology,
save consumption electricity (more than 30% saved in
comparison
with other crystallizer) and it has an excellent
efficiency reflector.
3. The system can be cope with flexible layout for the existence preform
production line.
4. For obtain to more accurate boundary between crystallized and non crystallized
section,
the water cooling chamber (heat insulation) was
designed by our own ideas.
5. Rotation core is composed of supporting part of preform and heat insulation
part.
And to improve the crystallization quality such as dimensions,
contour of neck,
crystallinity and position of crystallization boundary,
all our technology is focused on
this device.
6. Heater unit and cooling chambers are easy to put on and take off due
to
they are modular designed.
7. SCR controlled heater intensity and the life of heater is improved.
8. The whole operation and set up the conditions for the crystallizer is
able to
control under a touch panel with alarm, therefore setting
of optimized
crystallizing condition and process operation is very
simple and quick.
9. The system is designed for minimized floor space utilization.
|
|
