Multiple Layer PE Pipe Production line

Multiple Layer PE Pipe Production line 

THE CO-EXTRUSION PROCESS

In standard extrusion, solid plastic pellets are gravity fed into a forming mechanism, where jacketed compression screws melt and feed the materials into a die. By contrast, Co-extrusion involves multi-layer extrusion forming layered or encapsulated parts. Sometimes five or more materials are used in a single cycle, with each extruder delivering the precise amount of molten plastic needed for the operation.

Unlike ordinary plastic mixing, each individual plastic retains its original properties, but is combined into a compound-material part. If mixed prior to extrusion, the characteristics of the individual materials may be altered, but the end result is a homogeneous product.

Not all plastics are suitable for co-extrusion because some polymers will not adhere to others, although introducing a conductive middle layer can often solve this problem. Plastics with drastically different melting temperatures are also unsuitable for the process, as degradation will occur in the lower melting material. Finally, PVC and acetals should never be coextruded together because of the potentially violent reactions that can occur when they are joined.

THE COMPLETE EXTRUSION LINE IS COMPOSED OF THE FOLLOWING ITEMS:

· Single screw extruder

· Co- extruder: manufacturing marking line on pipe or multilayer of pipes

· Die head

· Vacuum tank: due to diameter, it can be designing of single, double vacuum chamber

· Cooling tank: due to diameter, the numbers of cooling tank can be one, two or three

· Haul-offs: due to diameter, it can be designing of double, three, four, six, eight, ten, twelve caterpillars

· Cutter: due to diameter, it can be designing of no-scraps cutter or planetary cutter

FEATURES:

                    *PLC control, high automation;

                    *Adopting specialized screw with good plasticizing effect.

                    *Vacuum calibration, constant temperature control, eliminating pipe stress;

                    *Adopting co-extrusion head to add color line;

                    *High extrusion capacity, low and equal temperature of melt.

                    *Wide processing range of raw materials.