datasheet CPP extrusion - SML

CPP extrusion
base material for metallizing, laminating, and converting
Cast polypropylene films are the base
for a variety of packaging applications.
Produced mostly as three-layer or
five-layer structures, they need to have
excellent transparency for subsequent
printing and laminating as well as low
gauge variation for metallizing. Typical
applications include films for bags
and pouches, wrapping films, textile
bags, candy wrap, antifog and peelable
structures.
Automatic resin supply and gravimetric
dosing systems for up to six
components are placed directly above
the individual extruders. SML’s range
of extruder diameters and L/D ratios
match the viscosities to make sure that
the materials processed give consistent
high-quality melt for perfect film
properties.
Feedblock technology and automatic
dies in combination with beta-gauging
sensors are standard features. Web
stability is enhanced by means of the
SML vacuumbox, the use of electro-
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Bundesstrasse 1a
A-4860 Lenzing
Austria - Europe
static edge pinning, and an airknife or
softbox. The casting section makes
sure that the polypropylene film obtains
all properties such as excellent
clarity and gloss, low haze, wide hot
tack range, low seal initiation temperature
and tolerances and is, finally, easy
to convert.
The casting section is designed to
minimize vibrations and allows for
high production speeds, in the case
of CPP rates around 350 m/min, line
speeds being limited by raw material
properties. Edge trimming and inline
recovery assure the best possible use
of the raw material. Corona treatment
is necessary for subsequent converting
steps such as printing, metallizing,
or lamination.
SML’s series 2000 winders will, at the
very end of the process, wind small or
large-diameter rolls with the possibility
of part bobbin slitting. Fully automatic
shaft, roll and core handling are additional
features for efficient cast film
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Fax: +43 7672 912 9
e-mail: sml@sml.at
extrusion systems. SML’s reliable series
1050/1100 and 1200 turret winders
are used in CPP lines as alternative.
SML cast film lines are equipped with
the latest servo-drive technology, and,
of course, feature the SML’s control
system. As all lines are tested at SML
prior to delivery, we can ensure fast and
reliable installation and startup at our
customer’s site.

CPP extrusion
base material for metallizing, laminating, and converting
product
polymers
film thickness range
range of final endfilm width
mechanical speed
line configuration raw material handling
feed system
gravimetric dosing
extruder output control
extrusion
extruder diameters
L/D ratio
melt filtration
melt pumps
coextrusion structures
extrusion die
casting and downstream equipment
primary chill roll
secondary chill roll
chill roll width
web pinning
gauging system
corona treatment
edge trimming and recovery
trimming station
suction system
scrap reprocessing
winding
basic concept
cross-cutting system
new roll startup
core specification
max. outside roll diameter
full width winding
part bobbins
shaft and roll handling
automation
www.sml.at
printed 02/2009
We reserve the right to technical modifications.
PP-Homo, PP-Copo
18 - 250 µm
up to 4500 mm
up to 350 m/min
individual pneumatic hopper loaders
up to 6 components per extruder
integrated in SML control system
30 / 45 / 60 / 75 / 90 / 105 / 120 / 135 / 150 / 180 / 220 mm
28 or 33
hydraulic screen changers
available on request
3 or 5 layers
with automatic cross profile control
ø 800 or 1000 mm, matt chill roll surface
ø 400 mm, chromium-plated surface
2300 / 2500 / 2700 / 2900 / 3200 / 3500 /
3800 / 4100 / 4400 / 4700 / 5000 mm
by combination of vacuum box, softbox or airknife
and electrostatic or pneumatic edge pinning
beta-ray gauging system
one-side, two-side, or alternating-side treatment
inline edge and bleed trimming with blades
edge and bleed trims are sucked off independently
direct refeed by vertical scraptruder or repelletizing on
inline recycling extruder
SML series 2000 winders
full width with guillotine
without core preparation
using belt cage
cardboard or plastic core
3” or 6” inner diameter
operating full width
up to 1000 mm
on 6” core possible
inline part bobbin
slitting possible
optionally available
SMILE control system
SML series 1100 winders
full width with guillotine
without core preparation
using electrostatic
cardboard or plastic core
3” or 6” inner diameter
operating full width
up to 1000 mm
on 6” core possible
inline part bobbin
slitting possible
optionally available
SML series 1200 winders
full width with twisting knife
without core preparation
using electrostatic
shaftless with steel core
6” or 8” inner diameter
operating full width
up to 1300 mm
on 8” core possible
inline part bobbin slitting
as option, on 6” and 8”
cores with shafts possible
with hall crane, supplied by
customer
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