• Malik Engineers

Plastic Sheet Extrusion Unit

Malik Engineers have developed a plastic sheet extrusion unit for producing sheeting from HIP/ABS/RPVC/SPVC/Polycarbonate/Cellulose Acetate/CAB and other plastic materials. The sheeting line consists of one single screw extruder fitted with T-die at its discharge end, polish roll set (cooling roll set), idler rollers set, pressure roller unit, torque motor winder for winding the flexible sheet (cutter is supplied for sheets which are rigid and cannot be wound) and a control panel for the complete machine. The plastic material in granular form is fed to the extruder, where it is mixed homogenously, melted and continuously forced out of a slit opening of T-die. The hot sheet, so produced, enters the nip between the top and centre rolls and passes over the bottom roll in "S"fashion. The rollers are provided with circulation of cool water which cools down the sheet as it passes over them. The set sheet is further supported by idlers as it passes over them for some distance and enters in the nip of pressure-cum-pulling rollers which help to maintain the sheet in proper tension. Side trimming knives trim down the sheet edges to get perfect width of sheet. The finished sheet is either wound on winder (if flexible) and cut to required lengths and slacked (if rigid). The control panel is fitted with electronic temperature controllers with sensors to accurately control the process temperature. In addition, electronic thyristor controllers for DC motor for extruder, cooling rollers and pressure-cum-pulling rollers are also fitted therein along with complete instrumentation. An optional feature for the above machine consists of a gear pump fitted to the extruder, which not only increases the output from the latter, but also ensures production of precision sheet with comparably improved mechanical strength.