A new XPET (PET foam) line is currently under testing at Union Officine Meccaniche headquarters in San Vittore Olona (MI) for the production of foam sheet for thermoforming and not just for it. The line is equipped with a drying system for raw material and a gravimetric dosing system "loss in weight" type.
Two extruders in Tandem, twin screw and single screw, guarantee a hourly production of over 300 kg/h with sheet width of 1100 mm and thickness adjustable from 1 to 4 mm. The weight reduction is considerable because by changing an expanding gas quantity weights ranging from 90 a 300 kg/m³ can be obtained.
Union's Tandem (twin screw + single) solution facilitates the achievement of the extrusion quality in particularly short times, even for a critical material such as PET where temperatures reach even 280° C.
The rheological study of the product has allowed the company to produce a circular die with which, although varying the thickness and density, it is not necessary to change the die's male.
A new extruder cooling system keeps the temperatures at the set value, which is very important when using expanding gases to achieve a perfect cell formation.
A very important detail is also a cooling can with a particular surface studied by Union. According to company, it avoids any friction and makes the surface of the sheet of appearance and brilliance at the top of all expanded extrusions.
The process management software, also developed by Union, makes all the management simple and reliable, the system is all integrated from the formulation of raw materials to the winding system.
About the company
Since 1950, UNION plans and manifactures, inside its factory in San Vittore Olona – MI, complete extrusion lines and all the parts which is composed, for rigid and foam plastic materials. UNION produces single and twin screw extruders beside complete extrusion lines for sheets,foils, profiles, hollow sheets at 2 and more walls. Special lines for composite panels of plastics and metal, complete lines for undulated and greca sheets of PMMA, PC, PET.