If metal particles are mixed into the material, it will cause serious damage to the components of the injection machine. During operation, injection machines mainly rely on screws to heat and melt plastic materials, and push them into the mold. This process involves mechanical movements of high pressure, high speed, and high temperature. If there are metal particles in the material, they will participate in the entire conveying and heating process in the form of foreign objects, which is extremely detrimental to the internal structure of the machine.

Metal particles can cause direct mechanical wear on the screw and the inner wall of the barrel. Screws and barrels are usually made of high-strength steel, and their surfaces are precision treated to ensure smooth flow of plastic. However, the hardness of metal particles is usually higher than that of plastic. Once pushed by the screw, they will continuously scratch the surface of the screw and the inner wall of the barrel like sandpaper, accelerating their surface wear, resulting in increased gaps and decreased sealing, ultimately affecting the uniformity of the melt and the stability of injection.

These metal particles may not melt at high temperatures, forming foreign objects that block the nozzle or hot runner system, causing the injection channel to be obstructed and the pressure to rise abnormally. This not only leads to unstable injection, but may also damage the nozzle, heating ring, and even the mold itself. If metal particles enter the hydraulic system or sliding parts, it may also cause oil circuit blockage or poor movement, increasing the risk of equipment failure.

Metal particles may also undergo adverse chemical reactions with plastic materials at high temperatures, contaminating the materials or producing harmful gases, affecting product performance and operational safety. Before injection molding production, it is usually necessary to use magnetic separators or filtering devices to thoroughly purify the raw materials, ensuring that they do not contain metal impurities or foreign objects, in order to protect the core components of the injection machine, extend the service life of the equipment, and ensure the stability and consistency of the finished product quality.