Talking about the components of plastic extruder

The main engine of the plastic extruder is composed of extrusion system, transmission system and heating and cooling system. 

The extrusion system includes a screw, a barrel, a hopper, a die, and a die. The plastic is plasticized into a uniform melt through the extrusion system, and pressure is built up during the process, which is continuously extruded by the screw. 

1. The screw is the main component of the plastic extruder, which is directly related to the application range and production efficiency of the extruder. It is made of high-strength and corrosion-resistant alloy steel.

2. The barrel is a metal cylinder, generally made of alloy steel with high heat resistance, high compressive strength, strong wear resistance and corrosion resistance or composite steel pipe lined with alloy steel. 

The barrel cooperates with the screw to realize the pulverization, softening, melting, plasticizing, exhausting and compacting of the plastic, and continuously and uniformly convey the rubber material to the molding system. 

Generally, the length of the barrel is 15 to 30 times its diameter, so that the plastic can be fully heated and fully plasticized.

3. The bottom of the hopper is equipped with a cut-off device to adjust and cut off the material flow, and the side of the hopper is equipped with a viewing hole and a calibration metering device.

4. Machine head and mold: The machine head is composed of an alloy steel inner sleeve and a carbon steel outer sleeve, and a forming mold is installed in the machine head. The function of the machine head is to convert the rotating plastic melt into parallel linear motion, evenly and smoothly introduce it into the mold sleeve, and give the plastic the necessary molding pressure. 

The plastic is plasticized and compacted in the barrel, and the porous filter plate flows into the molding die of the die through the neck of the die along a certain flow channel. A continuous and dense tubular cladding layer is formed around the core wire. 

In order to ensure a reasonable plastic flow channel in the machine head and eliminate the dead angle of accumulated plastic, a shunt sleeve is often installed. In order to eliminate the pressure fluctuation during plastic extrusion, a pressure equalizing ring is also installed. 

The machine head is also equipped with a mold correction and adjustment device, which is convenient for adjusting and correcting the concentricity of the mold core and the mold sleeve.