Film Overview
 ITWSPS
manufactures several types of stretch film for use in virtually
every hand or machine application.
Whether the situation requires high stretch, strength, clarity,
quiet unwind, or load holding ability, ITWSPS has the right
product for the job.
How Stretch Film Is Made
Plastic pellets, called resins, arrive by
rail car and are stored in large silos. Different types of resins
are then mixed in hoppers according to a special “recipe.”
 Blown
Flim
In the blown film process, the resin pellets
are melted and forced through a circular die. Cold air is blown into
the center and around the outside perimeter of the molten film and
forms it into a cylindrical bubble rising 30 feet into the tower.
The thickness of the bubble wall can be as small as half of 1 thousandth
of an inch and must be held to close tolerances. The bubble cools
as it moves up the tower. Upon reaching the top the bubble is then
collapsed and cut into two film webs as it travels back down. Finally,
the webs are trimmed to size and wound around cores to form the rolls
of stretch film that are sold to customers.
 Cast
Film
The cast manufacturing process is a bit different.
After the plastic resin pellets are mixed and melted, the molten
plastic is extruded through a wide, precision-made die onto a rotating
drum. The drum has a highly polished stainless steel surface and
is filled with a chilled liquid to keep it at around 60 degrees.
The surface of the drum gives cast film its clear, smooth appearance.
After the film solidifies on the drum's surface, it is then fed
to the slitters, then the winder.
Continual testing of random film samples assures
that only top quality film is shipped to our customers. Popular
types and sizes of stretch films are kept in stock to assure a
timely delivery.
|
 |
|
