PET / R-PET SHEET
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EXTRUSION LINES - ENGINEERED TO PERFORM ►

SHEET lines LINES FOR PET SHEET EXTRUSION

Sheet lines INTRODUCTION PET consumption has risen enormously during the past two decades. Bottles and textiles are the main products, but rigid packaging for food and other technical and consumer items also account for a significant volume. This development leads to the question as to why PET has become so attractive in comparison with other materials and whether or not it’s growth will continue? Outstanding properties such as high transparency and stiffness, as well as excellent thermo-formability have convinced an increasing number of converters to switch to PET sheet. Moreover, parallel...

Sheet lines LINES FOR PET SHEET EXTRUSION

Sheet lines MATERIAL DRYING MATERIAL DOSING ROLL STACK GAUGING SYSTEM FILTRATION SYSTEMS

Sheet lines EDGE TRIM CUTTING/REMOVAL WINDING UNIT

Sheet lines standard extruder Single-screw extrusion with pre-drying With this system, minimized IV (intrinsic viscosity) reduction allows the production of top quality sheet. As compared to other equipment, single-screw extruders are robust and easy to operate. Two separate single-screw extruders with a dryer represent a typical co-extrusion for the production of standard 3-layer structures (A/B/A). In combination with IR-drying, which reduces drying times by more than half, the main components such as virgin material, flakes and regrind material are pre-mixed, then predried in an IR-dryer...

Sheet lines Vacurema extruder Recycling extruder (Vacurema system) This single-screw extrusion system is ideal for flakes and regrind processing. The process complies with the regulations of European and US authorities (EFSA / FDA) as suitable for the decontamination of post-consumer bottle flakes for food contact packaging. In its key components the system consists of a vacuum reactor, which is linked directly to a single-screw extruder. The patented pre-treatment at high temperature and in high vacuum before the extrusion process, removes moisture and migration materials from the...

Sheet lines conical twin-screw extruder Conical twin-screw extruder The conical twin-screw extruder offers great flexibility for the processing of flakes, regrind and virgin granules. Moreover, this extruder can also process other polymers such as PP or PS. Depending on the moisture level in the raw material and the required sheet quality, PET can be processed without pre-drying in a twin-screw extruder, which has a positive effect on total energy consumption. Conical twin-screw extruder output: Output for PET max. kg/h When material is additionally pre-dried before processing, the IV loss...

Sheet lines continuous double pistion filters Filtration systems Different filter types are selected in line with the extruder design and the expected level of impurities in the raw material: ¡ ¡ ¡ Single-piston, hydraulically actuated discontinuous filters Double-piston, hydraulically actuated continuous filters Backflush filters with up to 12 cavities In order to guarantee stable pressure and good melt homogenization in front of the die, SML PET lines are equipped with melt pumps and static mixers. Schematic drawing 8-cavities back-flush filter during production backflush position tool unit

Sheet lines Feedblock and flat die As a leading supplier of high-quality PET sheet lines, SML relies exclusively on reputated partners for its feedblocks and flat dies. A 3-layer A/B/A sheet structure with thin outside layers is typical for the following main reasons: The SML die splitting system provides quick and safe opening of the die for cleaning purposes. The die stays in its original position in the machine and remains electrically connected for heating! ¡ The opportunity to run with virgin material only in the two outside layers, while using recycled material in the middle layer....

Sheet lines horizontal roll stack roll stack SML PET lines are highly respected in the market because of their outstanding roll stack technology, which results in superior thickness tolerances. All the SML roll stacks for PET sheet are equipped with the specially designed SPG (Smart-Parallel-Gap) C0 polishing roll. Moreover, the C1 (main) and C2 (secondary) cooling rolls with thin outer shells enable a high specific output, due to improved heat transfer. All three rolls are hardened to 60+/-2 HRC, chromium plated and polished to a high-gloss mirror finish. Each roll is equipped with a...

Sheet lines inclined roll stack For very thick and heavy gauge sheet SML supplies roll stacks with inclined roll arrangement, which is the optimal design for these products. In its standard designs, SML offers gap adjustment using manually adjustable spindles with scales and readings. As an option, motorized gap adjustment is available. AC servo-motors drive the spindles and the values are displayed on a touch screen in the control panel on the roll stack and stored in the SMILE recipe control system. A very useful optional feature is the nip load measurement system, which shows the actual...

Sheet lines inline thickness measuring unit with inductive / capative sensor gauging system In answer to the various regulations in customer countries and specific product needs, SML supplies different automatic gauging systems: ¡ Inductive / capacitive sensors ¡ Air caliper systems ¡ Radioactive Beta-ray sensors (Krypton 85 or Sr 90) ¡ X-ray sensors ¡ Laser shadow All these systems are available for dies with manual adjustment or automatic profile control and are equipped with a control for the speed of the main cooling roll C1, to maintain the value of the thickness setting in machine...

Sheet lines Winding systems SML customers can select from a wide range of different semiand fully-automatic sheet winding systems for PET. Semi-automatic winders work in combination with an accumulator, which picks up the sheet during the manual change of the roll in the winder. All winders are designed and built by SML. The accumulator works from a bottom to top position, while a torque-driven servo-motor generates storage movement and precise web tension. ¡ Film capacity: standard 38m, others possible on request ¡ Guide roll diameters of 120 and 160mm available ¡ Access doors at operation...