We have emphasized many times: the screw and barrel are the most critical and essential components of an injection molding machine. During injection molding production, the plastic raw material enters the barrel from the rear, and the screw rotates at high speed inside the barrel, compressing and pushing forward the plastic pellets and their fillers, mixing and plasticizing them as they advance, and injecting them into the mold cavity from the screw tip. At this stage, the barrel and screw are subjected to certain high temperatures and high pressures; the operating temperature of the injection screw varies depending on the type of plastic being processed.
Screws and barrels often become unserviceable and must be scrapped because excessive clearance caused by wear prevents normal extrusion and injection. Wear increases the clearance between the screw flight and the barrel wall, which leads to a reduction in melting rate and pumping capacity, causes uneven material temperature and pressure fluctuations, degrades product quality, and simultaneously lowers productivity while increasing energy consumption. Compared with the barrel, the screw is more susceptible to damage and failure.
