The plasticizing requirements of the injection screw barrel mainly include controlling the temperature of the barrel, adjusting the speed, checking the debris in the plastic and ensuring that the plastic is dry. These requirements are designed to ensure that plastics are uniformly plasticized during injection, reducing wear on the screw and barrel, thereby improving injection quality and efficiency.
First of all, each plastic has an ideal processing temperature range, and it is very important to control the cylinder temperature to get close to this range. During the process of the plastic in the cylinder through the charging section, compression section and homogenization section, the appropriate temperature is required to ensure that the plastic is fully melted and evenly mixed. If the temperature is too low or too high, it will lead to uneven plastic melting and increase the wear of the screw and barrel .
Secondly, the adjustment of speed is also an important parameter in the plasticizing process. Too high a speed may cause the hardening agent in the plastic such as glass fiber to be torn up, increasing wear. Therefore, it is very important to adjust the appropriate speed according to the nature of the plastic .
In addition, before injection molding, it is necessary to check whether there is debris in the plastic, such as metal chips, paper clips, etc., which will cause serious damage to the screw and barrel. These are usually removed by installing magnet holders .
Finally, ensuring that the plastic is dry is also part of the plasticization requirements. The moisture in the plastic will form steam particles during the injection molding process, causing wear to the screw and barrel, and may cause the plastic to crack, producing harmful impurities .
