The extrusion method of a plastic extruder generally refers to melting a plastic at a high temperature of about 200 degrees, and the molten plastic forms a desired shape when it passes through the mold. Therefore, temperature control is undoubtedly an important process control in the production process of plastic extruder. The quality control directly affects the quality of the product.
Heater heating (external heat): At present, plastic extruders use electric heating, clean, effective and easy to control heating. That is to say, the electric heater (with the resistance wire) is packaged on the barrel, and the material is heated and heated, and the material is heated and melted by the joint action of heat conduction, convection and radiation. The current heaters usually have mica heaters, ceramic heaters, cast aluminum heaters, cast copper heaters, cast iron heaters, etc. The efficacy of various heaters is somewhat different. The mica heater has lower cost and is easy to process. The service life is short; ceramic heaters and cast iron heaters have higher power, faster heating, can rise above 300 °C or higher, and have a relatively short life span, which is longer than mica heaters. Cast aluminum heaters and cast copper heaters are most commonly used because of their high thermal efficiency, good thermal insulation performance and long service life.
Shear friction heat (internal heat) during extrusion of plastic extruder: heat generated during deformation of plastic particles due to strong extrusion pressure, between plastic particles and between particles and barrel Heat generated by friction with the screw. During the heating process, the temperature rise inertia, in the heating and heating process, regardless of the heating method, stop heating, because the temperature rise inertia, the temperature will continue to rise, then you need to watch the control parameters, accuracy and so on. The shear friction heat (internal heat) during the extrusion process of the plastic causes the processing temperature to rise continuously, destroying the characteristics of the material and causing the material to become a waste product.