Add water or appropriate liquid to the raw material powder, and keep stirring. The stirred material is extruded from a porous die or metal mesh with high extrusion pressure. Usually, after the material is put into a cylindrical container, the material is extruded by a screw. After using the frequency conversion technology, the pressure can be controlled, so that the appropriate linear speed can be selected. Principle of Single Screw Extruder Single screw is generally divided into three sections in effective length. The effective length of the three sections is determined according to the screw diameter, pitch and screw depth, which is generally divided into one third each. The last thread of the nozzle is called the conveying section at first: the material here should not be plasticized, but it should be preheated and compacted under pressure. In the past, the old extrusion theory thought that the material here was a loose body, and later it was proved that the material here was actually a solid plug, which means that the material here is a solid like a plug after being extruded, so its function is to complete the conveying task. The second section is called the compression section, at this time, the volume of the screw groove gradually decreases from large to small, and the temperature should reach the degree of material plasticization. The compression generated here is from the third conveying section to one, which is called the compression ratio of the screw (3: 1). Some machines also change, and the plasticized material enters the third section. The third section is the metering section, where the material is kept at the plasticizing temperature, and only the melt material is accurately and quantitatively transported like a metering pump to supply the die head. At this time, the temperature cannot be lower than the plasticizing temperature, which is generally slightly higher.

Pay attention to the following when using extruder:

1. The extruder should run forward to avoid inversion.

2. Avoid running on an empty stomach, and be sure to feed the heat engine, so as to avoid the phenomenon of stick bars (holding shafts).

3. It is strictly forbidden to enter the iron and other miscellaneous materials in the feed port and vent hole of the extruder, so as not to cause accidents and affect production.

4, safe electricity, grounding wire.

5. When the machine is running, it is forbidden to touch the rotating parts such as feed port, discharge port, belt and gear with hands.

6. Before using the machine, inject lubricating oil to avoid damage to the machine. The function of extruder is to transform solid plastic into uniform melt by heating, pressurizing and shearing, and send the melt to the next process. The production of melt involves the processes of mixing additives such as masterbatch, blending resin and re-grinding. The finished product must be uniform in concentration and temperature. The pressure should be large enough to squeeze out the viscous polymer.