What is the wear mechanism of the screw and barrel? What are the common wear repair methods?

As critical components in plastic extruders, screws and barrels often face various types of wear problems. These wears are mainly caused by the continuous friction and mixing of plastic particles with the surfaces of the screw and barrel under high temperature and high pressure during the extrusion process. Among them, friction wear is the most common type. Plastic particles continue to rub on the contact surface between the screw groove and the inner wall of the barrel, gradually causing wear and debris on the metal surface. In addition, corrosive wear is also an important factor, especially when dealing with plastic materials containing corrosive additives. Chemicals may corrode the metal surface and accelerate the occurrence of wear.

In response to these wear problems, engineers use a variety of repair and protection measures to extend the service life of screws and barrels. Surface coating repair is one of the common methods. By coating wear-resistant metals or alloy materials, the wear resistance of screws and barrels can be effectively enhanced. This method can not only repair existing wear, but also improve the hardness and wear resistance of the surface, and extend its reuse cycle. On the other hand, surface heat treatment is also widely used. Through high-temperature treatment technologies such as nitriding or carbonitriding, the hardness and wear resistance of the metal surface can be significantly improved, thereby effectively resisting friction and wear during extrusion.

Precision grinding repair is a common technical choice for parts with severe wear or large dimensional changes. Through the precise grinding process, engineers can restore the original geometry and size of the screw and barrel to ensure its precise operation in extrusion production. For severely damaged parts that cannot be repaired, it may be necessary to consider replacing the entire screw and barrel components to ensure the normal operation and production efficiency of the equipment.

In addition, regular preventive maintenance is essential to reduce wear problems. Through regular inspection, lubrication and correct operation, the service life of the screw and barrel can be effectively extended, unexpected downtime can be reduced, and the continuous and stable production capacity of the extrusion equipment can be ensured.