Extruder roller plays a vital role in the process of plastic extrusion production.
1. Material
Usually made of high-quality alloy steel, it has high strength, high hardness and good wear resistance, and can withstand high temperature, high pressure and friction during extrusion.
Some high-end extruder rollers may be made of special alloy materials or surface treatment, such as chrome plating, hard chrome plating, etc., to further improve their performance and life.
2. Shape and size
Generally cylindrical, the diameter and length are determined according to the specifications of the extruder and production needs. Larger diameter rollers can provide greater extrusion pressure and better plasticizing, while longer rollers can increase extrusion yield.
The surface of the roller is usually precision machined to ensure its surface finish and flatness, reducing the resistance and wear of the plastic during extrusion.
3. Internal structure
The extruder roll is usually equipped with heating and cooling channels to control the temperature of the roll. The heating channel can be heated by electric heating, steam heating or hot oil heating, and the cooling channel is usually water-cooled or air-cooled. By precisely controlling the temperature of the roller, good plasticization and extrusion of plastics can be achieved.
1. Plastic feeding
Plastic particles or powders enter the interior of the extruder through the hopper of the extruder and are transported forward by the rotation of the screw.
2. Plasticizing process
When the plastic enters the gap between the extruder roll and the screw, it is heated by the roller and the shear of the screw, and gradually softens and melts to form a uniform plastic melt.
3. Extrusion process
The plastic melt is pushed by the screw and extruded through the die head of the extruder to form the plastic product of the desired shape. During the extrusion process, the roller provides the necessary extrusion pressure to ensure that the plastic melt can pass smoothly through the die head.
1. Plasticization
The extruder roller softens and melts the plastic particles or powder through heating and shearing of the screw to form a uniform plastic melt. Good plasticizing effect can improve the quality and performance of plastic products.
2. Extrusion pressure
The roller provides the pressure required during the extrusion process, ensuring that the plastic melt can pass smoothly through the die head to form the plastic product in the desired shape. The size of extrusion pressure directly affects the density, dimensional accuracy and surface quality of plastic products.
3. Temperature control
The heating and cooling channels inside the roller can precisely control the temperature of the roller, thus realizing the control of the temperature of the plastic melt. The appropriate temperature can improve the plasticizing effect and fluidity of plastics, reduce the degradation and thermal decomposition of plastics, and improve the quality and stability of plastic products.
4. Wear and corrosion resistance
Due to the friction and chemical corrosion between the plastic and the roll surface during the extrusion process, the extruder roll needs to have good wear and corrosion resistance to ensure its long-term stable operation.
1. Clean regularly
Regularly clean the dirt and plastic residue on the surface of the extruder roller to maintain its surface finish and flatness and reduce the resistance and wear of the plastic during the extrusion process.
2. Check and replace the worn parts
Regularly check the surface wear of the extruder roller, and if necessary, timely replace severely worn parts, such as chrome or hard chrome on the surface of the roller.
3. Temperature control and maintenance
Ensure the normal operation of the heating and cooling system of the extruder roller, regularly check the accuracy and reliability of the temperature sensor and controller, and timely repair or replace the faulty parts.
4. Lubrication and maintenance
Regularly lubricate and maintain the transmission parts of the extruder roller to ensure smooth operation and reduce wear and noise.
In short, the extruder roller is a key component in the plastic extrusion production process, and its structural characteristics, working principle, role and function, as well as maintenance and maintenance have an important impact on the quality and production efficiency of plastic products. When selecting and using extruder rollers, it is necessary to select the appropriate roller material, shape and size according to the production needs and the characteristics of the plastic material, and carry out the correct maintenance and maintenance to ensure the long-term stable operation of the extruder and the quality of the plastic products.
