Plastic sheet production line

LJC built its first wholly designed and in-house manufactured extruder in 1984
The model was a D120( 120 screw diameter) 35: 1 L/D liquid cooled extruder and had a throughput of 550 kg/h, using polypropylene material.

The original LJC extruders screw design for various materials ( PP-PS-PET-ABS-Multilayer) has been extensively tested and is constantly upgraded to fit the raw materials improvements, to achieve optimum quality and throughput.
LJC EXTRUDERS can be supplied in a range from 45 mm to 150 mm, with air or water cooling system. The L/D ( length/diameter) ratio is from 30/1 to 35/1.
The barrel supply collar has, on the inside, a cooling circuit at controlled temperature. Cooling of extruder cylinder in the water-cooled models is by an independent central unit, while cooling of extruder cylinder in the air-cooled models is by motor-ventilators for each single control zone. The number of control zones ranges from 4 to 7 according to the model and their temperature is controlled by a computerized LJC system.

The screw thrust has an axial roll-bearing and abundantly dimensioned rolls.
The connection between motor and gear is direct, through an elastic joint, suitable for absorbing bumps and vibrations.
The extruder barrel is made by two-metal alloy; In the smaller models (D45-D60-D80), is made by nitrided steel as standard, by two-metal alloy as optional. The gear, the barrel and the motor are installed in a single structure, solidly made of electro-welded pieces. Special covers in stainless steel, easily removable, protect the heater cylinder zones.
THE EXTRUDER MOTOR is AC or DC, complete with motor-ventilator. The extruder motor is placed under the barrel to reduce overall dimensions, while the motor drive, variable speed and constant torque, is included in the general control panel of the extruder. The venting plant is made up of: Liquid ring, vacuum pump, flowmeter for pump protection. A water-reclaiming system can be optionally supplied.

THE HYDRAULIC SCREENCHANGER can be in two versions:

Single filtering system
Double filtering system ( continuous filtering), without any flow interruption
There is also a separate hydraulic central unit for the filter plate exchange, which can be used to supply other extruders.
All the extruders are equipped with a GEAR PUMP SYSTEM
The gear pump system includes a DC motor, a gear-box, a cardan joint and a control system on the general control panel.
All the extruders can be supplied with various ACCESSORIES.

Material pressure readout
Material temperature readout
Static mixer
The LJC CALENDERS are divided into four basic models, identified by the rolls diameter:
750-500-350-250 mm. The calender and the haul-off can be made in one only structure for 250 and 350 mm versions; Or in 2-3 pieces ( calender-extra cooling roll-haul off) for the 500 and the 750 mm versions.