Injection molding machine screw barrel maintenance includes regular cleaning, inspection and lubrication to keep the screw in optimal condition.
As the core component of the injection molding machine, the screw barrel is directly responsible for the melting and conveying of plastic raw materials.
When it operates normally, it can ensure that the plastic is fully melted and the material is stably fed, so that the quality of the products produced can be guaranteed.
However, if daily maintenance is neglected, it may cause problems such as plastic deterioration, uneven melting, and even machine damage. This will not only affect the product qualification rate, but also shorten the service life of the entire equipment.
This article will explain the maintenance points of the screw barrel from the perspective of actual production, and provide directly operational suggestions.
Why should you pay attention to screw barrel maintenance?
- Improve work efficiency
- Extend equipment life
- Stable product quality
- Reduce unexpected downtime
Improve work efficiency
When you regularly maintain the screw barrel, the melting and mixing process of plastic will be smoother. This means that you can complete production tasks faster while ensuring that every part meets qualified standards.
Extend equipment life
Simple cleaning and inspection can help you avoid expensive replacement costs. Just like we often maintain our cars, maintaining the screw barrel can make it continue to work longer.
Stable product quality
A clean barrel is directly related to product quality. If you value the consistency of part appearance and size, keeping the barrel clean is the most effective way.
Reduce unexpected downtime
Preventive maintenance allows you to take the initiative. Instead of reacting to equipment failures, it is better to detect hidden dangers in advance-so that you don’t have to worry about sudden interruptions in the production line.
Essential Practices for Screw Barrel Maintenance
- Cleaning and inspection
- Temperature control
- Lubrication and maintenance
- Prevent foreign matter from entering
- Centering and calibration
Cleaning and inspection
- Clean the screw and barrel regularly and thoroughly to remove any residual plastic or impurities. If these things are left inside, the quality of the plastic parts produced will be affected.
- Every time you clean or regularly, carefully check the surface of the screw for signs of wear, scratches, deformation or rust. These damages will make the screw work unsmoothly and affect production.
Temperature control
- Always pay attention to the temperature display of each section of the barrel. And according to the process requirements of the plastic used, keep the temperature stable within the appropriate range. It is not okay to have a high and low temperature.
- It is very important to keep the temperature stable. If the temperature fluctuates too much, not only will the quality of the product be affected (such as uneven color and bubbles). Over time, it will also accelerate the wear of the screw and barrel and shorten their service life.
Lubrication and maintenance
- Choose appropriate lubricating grease according to the recommendations of the equipment manufacturer. Fill the parts that need lubrication (especially the screw and barrel) on time and in an appropriate amount.
- Good lubrication can effectively reduce the direct friction between the screw and the barrel and reduce the wear rate. Make the screw rotate more smoothly and the equipment run more smoothly.
Prevent foreign matter from entering
- Make sure the raw materials are clean! Protect the feeding port to prevent metal debris, sand, dust or other hard particles from mixing into the barrel.
- Once these hard objects enter, they will scratch the screw and the inner wall of the barrel at the least, or jam the screw at the worst. And it will definitely contaminate the plastic melt, causing defects in the final product.
Centering and calibration
- Regularly check whether the screw is well centered in the barrel. If it is installed crookedly or deviates during operation, it will cause uneven force, increased wear, and even damage the equipment.
- Related machine parameters and components (such as the end position of injection) also need to be calibrated regularly. This can ensure that each injection or extrusion action is accurate and consistent, and produce products with stable dimensions and reliable quality.
Guidelines for Deep Cleaning and Lubrication
Disassembly and cleaning process
- Shutdown and cool down to 30-50 ℃
- Remove the screw head/check ring
- Brass brush to remove residue
- Wipe with cotton cloth soaked in solvent * trichloroethylene
- Check for thread wear and cracks
- Apply high-temperature anti tightening paste to the threads
Note: Do not use steel brushes to avoid scratching the surface. Use wooden sticks wrapped in cotton cloth to clean the inner wall of the material cylinder
Lubricant selection criteria
- Lubricating grease: Lithium based grease (drip point>220 ℃) is recommended, suitable for high-speed scenarios (dn value>1000000), with a replenishment of 0.4cm ³/cycle every 800 hours.
- Oil lubrication: ISO VG32-68 turbine oil, viscosity needs to be matched with screw speed (e.g. recommended viscosity of 40cSt for 60mm screw).
Longevity Through Maintenance
Regular maintenance of the screw barrel of the injection molding machine can make it last longer and run more steadily.
Pay more attention to checking the equipment status, keeping it clean, adding oil and lubrication in time, and controlling the temperature – these seemingly simple habits can help you protect the screw barrel and make plastic products with good taste and high quality.
The Role of Haichen in Enhancing Screw Barrel Maintenance
In the production of flame-retardant materials, we use rust-proof screws and HPT fully hardened powder alloy materials to extend the life of the equipment to three times the original.
For PVC special machines, we use PP materials for flushing and heat preservation before shutting down every day. This simple daily operation reduces the machine failure rate by 90% a year.
When the screw needs to be repaired, the cost of the double alloy refurbishment solution is only 60% of that of a new part, but the wear resistance is increased by 40%.
As long as the factory pays attention to daily maintenance and follows the correct method to maintain the screw and barrel, it can extend the service life of the equipment, which can not only reduce downtime but also ensure the stable quality of plastic products.
