Screen changers are hydraulic devices, which ensure the effective filtration of the plastic melted in the extrusion process (e.g. PP, PS, PE, PET, ABS) before it is intended for granulation in the pelletizing systems. The important advantage of screen changers is the ease of use, which does not require any adjustment to improve tightness and thus it provides continuing of the extrusion process in extruders.

The principle of operation of the plate filter screen changers is based on the alternating, automatic or manual use of the various replaceable filter screens, fixed on specially designed sliding plates. To pass the material through the screen meshes, the screen plate is led into the filtration chamber of the device, from where it is discharged only after heavy contamination of the screen. Increasing the mass pressure inside the filtration chamber becomes a signal for manual or using a mass pressure sensor, the automatic change of the exchangeable screen. The plate screen changers are equipped with a hydraulic aggregate and a accumulator (condenser), so that moving the screen plate does not require stopping the extruder. Heaters placed in the changer body ensure constant temperature and adequate fluidity of the filtered material.

Double piston continuous screen changer consists of two drum type filters with large area for filtration, where the filter screen is wrapped on each slide bearing bars full of small holes – the same function as the breaker plates. The piston screen changer can ensure continuous production during screen changing. It is designed with pre-filling and air vent mechanism, no air bubbles in final products. This provides constancy and stability during the extrusion production process. It works well under the high pressure 400 bar (40 MPa) not impact the high performance.

Our company also manufactures simplier in design – manual screen changers, designed for lightly contaminated materials. To our Clients, we offer as well comprehensive consultancy, technical service and spare parts. We invite you to introduce yourself with our offer of the filter screen changers involving the JC and AJSZL series.

Configuration table for screen changers.

Plate screen changers

Model Heating power [kW] Screen diameter [mm] Molten plastic maximum pressure [MPa] Extruder output [kg/h]
JC-50 4 50 25 50 – 100
JC-100 6 100 25 100 – 200
JC-120 7 120 25 150 – 250
JC-150 8 150 20 250 – 400
JC-200 10 200 20 350 – 600
JC-250 12 250 20 500 – 800
JC-300 15 300 20 500 – 800

 

Double piston screen changers

Model Screen size [cm] Filtration area [cm2] Molten plastic maximum pressure [MPa] Heating power [kW] Extruder output [kg/h]
AJSZL-500 29,8 x 8,5 250 x 2 35 5 1000
AJSZL-1200 42,4 x 13 600 x 2 35 9 2000
AJSZL-1600 47,1 x 17 800 x 2 35 11 3000
AJSZL-2000 53,3 x 19 1000 x 2 35 12 4000
AJSZL-3000 64,4 x 22,5 1500 x 2 30 16 5000
AJSZL-4400 88 x 25 2200 x 2 30 20 8400
AJSZL-5650 94 x 30 2827 x 2 30 21 11000

    Advantages of screen changers include:

  • compact housing;
  • different mounting methods;
  • easy of use;
  • adaptation for direct connection to extruders;
  • stability of filtration parameters;
  • equipment with a self-sealing system (elimination of leaks);
  • reliable operation at high temperatures and pressure.
  • continuous operation (piston screen changers);
  • large filtration area meet the high output extrusion machine (piston screen changers);
  • venting grove discharge the gas mixed in the polymer melt (piston screen changers);
    Screen changers are intended for filter:

  • melted in extrusion process plastics such as: PP, PS, PE, PET, ABS before proceeding to granulation process.