CAST FILM LINES
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EXTRUSION LINES - ENGINEERED TO PERFORM ► CAST FILM LINES BARRIER FILM

CAST FILM lines LINES FOR CPP / CPE / CAST-PET BARRIER AND MONO ORIENTED FILM

cast film lines INTRODUCTION Cast film products are mainly used in the packaging industry, but technical, medical and stationery films are also important sectors. Indeed, the worldwide market for flexible plastic packaging is predicted to grow steadily within the next years. Owing to their good optical and mechanical properties, cast films play a significant role in the flexible packaging market. In most cases printing, metallizing or laminating with other materials represent the subsequent processes in the value chain. Both, film producers and converters, expect high film quality and...

Lithium Ion Battery Separator Film (LiBSF) Line 28

cast film lines LINES FOR CPP / CPE / CAST-PET BARRIER AND MONO ORIENTED FILM

6 CAST FILM LINES RAW MATERIAL HANDLING AND DOSING FEEDBLOCK AND FLAT DIE EXTRUDER CASTING STATION MELT FILTRATION AIR KNIFE / SOFTBOX

cast film lines Winding system Trim handling system Corona treater SMILE control system

cast film lines multilayer extrusion unit Raw material handling and dosing In view of the fact that raw material account for the major portion of the cost for the production of cast films, it is essential to ensure their efficient use in every film layer. A wide range of gravimetric batch blenders and continuous gravimetric feeders, if needed also suitable for high-temperature polymer processing and with up to six components per extruder, enable recipes to be run with great accuracy and repeatability. gravitmetric batch dosing system continuous gravimetric dosing system Moreover, the...

cast film lines Extruder Depending on the size of the extruder and the processed materials, the screws are available with armoured flights for extended wear resistance. SML extruders for cast film are designed according to the processing requirements for all the relevant polymers used in this market segment. A selection of standard versions with screw diameters from 45 to 220mm is available. As a rule, the extruders with an L/D ratio of 28 or 33 and bimetallic barrels are powered by energy-efficient, low-maintenance, water-cooled AC drives.

cast film lines HO-LT extruder This patented extruder is especially designed for the processing of temperature-sensitive polymers such as EVOH or adhesives. It is also used for the thin functional layers in coextruded structures. The result is a very low melt temperature, extremely stable output and high pressure generation. HO-LT stands for “High Output – Low Temperature”. The special screw and barrel configuration enables these machines to plasticize large amounts of polymer at relatively low screw speeds. SML offers the HO-LT extruder in two different sizes, which are typical for...

cast film lines extrusion tool unit Melt filtration Effective melt filtration for the removal of impurities, unmelted or cross-linked particles is most important. As a rule, SML installs manual filters or hydraulic single or double piston filters in its cast film lines. manual filter hydraulic filter Disk filters or candle filters are used for applications such as surface protection or medical films, which require the strictest melt quality. disc/candle filter

cast film lines As a leading supplier of cast film lines, SML relies exclusively on respected partners for its feedblocks and flat dies. Sophisticated MicroLayer or NanoLayer™ feedblocks are integrated on demand. T-channel die with fixed internal deckling Multilayer structures require great flexibility with regard to feedblock adjustability. Therefore, SML generally utilizes variable geometry feedblocks and inserts that can be profiled to optimize the thickness variations of the single layers. A 3-layer feedblock with three extruders is standard for the production of CPP film, but there is...

cast film lines Edge encapsulation system for barrier film Using the edge encapsulation system, it becomes possible to refeed the primary edge trim to one of the extruders, because this trim consists entirely of clean encapsulation material (PE or PP) and is not contaminated with any barrier material. Encapsulation makes the production of barrier films more economical and reduces the scrap rate significantly. enables quick and safe die opening for cleaning purposes. The die remains in its original position in the machine and continues to be heated. The two encapsulation channels are fed...

cast film lines edge pinning system Edge pinning A combined electrostatic and pneumatic pinning system fixes the film to the chill roll surface. Adjustable static power and air pressure, as well as easy positioning allow precise pinning and therefore solid contact between the film edges and the chill roll. Bi-Vacuum Box The box, which is mounted directly on the die body, consists of two chambers. The pre-chamber extracts the air stream generated by the rotating chill roll, while the main chamber maintains low air pressure between the extruded film and the chill roll and prevents air...

cast film lines chill roll unit Casting station In combination with the bi-vacuum box, the air knife or the softbox, the casting station has a significant influence on final product quality. Parameters such as the position relative to the flat die, chill roll temperatures and vacuum box or air knife settings have a direct effect on optical and mechanical properties of the film such as haze, transparency, tensile strength or shrinkage. The complete chill roll unit is adjustable in horizontal and vertical direction in order to ensure the correct casting position for each product. Electrical...

cast film lines For the production of thicker film, it is necessary to fix the film additionally onto the chill roll using either an air knife or a softbox. This also enhances film cooling, which results in better haze and transparency values. The SML air knife has a specially designed, internal air distribution system, which guarantees a constant airflow over the whole width of the air knife, and an adjustable lip gap. The air for the air knife is filtered to ensure that no particles are blown onto the film and the blower of the air knife is speedcontrolled. The softbox represents an...