As a supplier of Parallel Barrel Screws, I understand the significance of reducing screw wear. A well - maintained parallel barrel screw not only ensures high - quality extrusion but also extends the service life of the equipment, which ultimately leads to cost savings for our customers. In this blog, I will share some effective ways to reduce the wear of a parallel barrel screw.
1. Material Selection
The first step in reducing screw wear is choosing the right material. High - quality materials with excellent wear - resistance properties are crucial. For parallel barrel screws, materials such as alloy steels with specific heat - treatment processes are commonly used. These alloys are designed to withstand the high - pressure and high - temperature conditions during the extrusion process.
Alloy steels with high chromium and nickel content offer better corrosion and wear resistance. For instance, some advanced alloy steels can form a hard oxide layer on the surface during operation, which acts as a protective barrier against abrasion. As a supplier, we offer a range of Parallel Extruder Cylinder Screw made from different high - quality materials to meet the diverse needs of our customers.
2. Proper Lubrication
Lubrication plays a vital role in reducing the friction between the screw and the barrel. Using the right lubricant can significantly decrease wear. There are two main types of lubrication in the context of parallel barrel screws: internal and external lubrication.
Internal lubricants are added to the polymer resin. They reduce the melt viscosity of the polymer, which in turn reduces the shear stress on the screw surface. External lubricants can be applied to the screw surface during the manufacturing process or during maintenance. They form a thin film that separates the screw and the barrel, minimizing direct contact and wear.
It is important to note that the choice of lubricant should be compatible with the polymer being processed. Incorrect lubricants can cause issues such as poor product quality or even damage to the screw and barrel.
3. Optimal Operating Conditions
Maintaining optimal operating conditions is essential for reducing screw wear. This includes controlling the temperature, pressure, and screw speed during the extrusion process.
Temperature Control
Excessive temperature can cause the polymer to degrade, which may increase the abrasiveness of the melt. On the other hand, too low a temperature can result in incomplete melting of the polymer, leading to higher mechanical stress on the screw. Therefore, it is necessary to set the temperature within the recommended range for the specific polymer being processed.
Pressure Control
High pressure can increase the contact force between the screw and the barrel, accelerating wear. By adjusting the pressure to the appropriate level, we can reduce the stress on the screw. This can be achieved by optimizing the die design and the feed rate of the polymer.
Screw Speed
Running the screw at an appropriate speed is also crucial. High screw speeds can generate more heat and increase the shear stress, while very low speeds may cause uneven melting of the polymer. We recommend that customers consult the technical specifications provided by us to determine the optimal screw speed for their specific applications.
4. Regular Maintenance and Inspection
Regular maintenance and inspection are key to detecting and preventing excessive screw wear. Here are some important maintenance steps:
Cleaning
After each production run, the screw should be cleaned thoroughly to remove any residual polymer. Residual polymer can harden over time and act as an abrasive, causing wear on the screw surface. Special cleaning agents can be used to dissolve the polymer, and mechanical cleaning methods such as brushing can also be employed.
Inspection
Periodic inspection of the screw is necessary to detect any signs of wear, such as scratches, grooves, or deformation. Non - destructive testing methods, such as ultrasonic testing, can be used to detect internal defects in the screw. If any significant wear or damage is found, timely repair or replacement should be carried out.
5. Polymer Preparation
Proper polymer preparation can also help reduce screw wear. This includes drying the polymer before extrusion, removing any contaminants, and ensuring a uniform particle size.
Drying
Moisture in the polymer can cause hydrolysis during extrusion, which may change the properties of the polymer and increase its abrasiveness. Therefore, it is important to dry the polymer to the appropriate moisture content before feeding it into the extruder.
Contaminant Removal
Contaminants such as metal particles, sand, or other foreign objects in the polymer can cause severe wear on the screw. Using filters or sieves during the polymer handling process can help remove these contaminants.
Uniform Particle Size
A uniform particle size of the polymer ensures a more consistent melting process, reducing the mechanical stress on the screw. If the particle size is too large, it may cause blockages or uneven melting, while too small particles may lead to higher dust generation and potential wear issues.
6. Compatibility with Extruder Type
It is important to ensure that the parallel barrel screw is compatible with the extruder type. Different extruders have different design features and operating requirements. For example, some extruders may require a specific screw geometry or flight pitch to achieve optimal performance.
As a supplier, we offer a variety of screws, including Conical Screw for Extruder and Extruder Screw for Coperion, to meet the needs of different extruders. We can provide technical support to help our customers select the most suitable screw for their extruders.
7. Training for Operators
Well - trained operators are essential for reducing screw wear. Operators should be familiar with the operating procedures, maintenance requirements, and safety precautions of the extruder. They should also be able to recognize the signs of abnormal wear and take appropriate measures in a timely manner.
We offer training programs for our customers' operators to ensure that they have the necessary knowledge and skills to operate the extruder and maintain the parallel barrel screw properly.
In conclusion, reducing the wear of a parallel barrel screw requires a comprehensive approach that includes material selection, proper lubrication, optimal operating conditions, regular maintenance, polymer preparation, compatibility with the extruder type, and operator training. By following these guidelines, our customers can significantly extend the service life of their parallel barrel screws, improve the quality of their extrusion products, and reduce production costs.
If you are interested in our parallel barrel screws or need more information on how to reduce screw wear, please feel free to contact us for procurement and further discussions. We are committed to providing high - quality products and professional technical support to our customers.
References
- "Plastics Extrusion Technology" by Allan A. Griff.
- "Handbook of Plastic Extrusion Technology" by James F. Carley.
- Technical literature from leading polymer processing equipment manufacturers.
