Optical quality sheets

The main extruder with bimetallic barrel and coated screw is specifically designed to process Polycarbonate (also PMMA, PET-G, GPPS, SAN). 

A particular attention has been paid to the efficiency of the degassing system. 

High-precision gravimetric dosing units ensure constant feeding in synchronism with the gear pump and extruder screw revolutions.

A side extruder is responsible for depositing a thin layer of UV protection.

Everyone knows the criticality of the calendering system in order to obtain high optical quality sheets: it is precisely on the 3-cylinder calender that BG Plast has focused its main attention in the choice of both mechanical part and components. The calender has three 410 mm cylinders with a very high degree of finish and an internal high temperature pressurized water circulation.

The table of the cylinders depends on the width of the product. The standard for this type of plant is a table of 2300, to produce a 2000 mm finished product.

The geometry of the calender is variable thanks to the rotation of the upper cylinder around the axis of the central cylinder; this feature allows the calender to be shaped differently depending on the thickness of the sheet to be produced.

The transmission mechanics, motors and gearboxes, are designed to guarantee the rotation of the cylinders without any slightest vibration: an indispensable condition to obtain optical quality sheet. 

The extruded sheet is then protected with a polyethylene film, cut into lengths of up to 3000 mm and automatically laterally stacked thanks to a suction cup system.