25 Feb Unlocking Efficiency: The Importance of Screw and Barrel Maintenance in Injection Molding
Wear and tear in injection molding is inevitable. At the heart of this process lie the screw and barrel—key components of the injection molding machine that play a critical role in melting, mixing, and injecting plastic into molds. Proper maintenance of these components not only ensures consistent product quality but also extends the lifespan of your equipment, reduces downtime, and enhances operational efficiency.
Common issues include:
- Wear and tear caused by abrasive fillers or high temperatures from unexpected shear due to improper temperature setpoints
- Corrosion from moisture or certain plastic additives
- Material build-up due to degraded or improperly purged plastic that can cause uneven wear and reduce system performance.
Unfortunately, barrel and screw maintenance is an area that tends to get overlooked until a problem rears its ugly head. Some of these issues could be a loss of cushion at the end of pack and hold, screw recovery consistency or un-melted pellets causing cosmetic defects.
Taking a proactive approach to equipment maintenance may help eliminate premature wear. Below are a few ideas to ensure your equipment lasts for years.
- Implementation of a standard purging process during material changes or shutdowns. This helps ensure high temp resins do not remain in the barrel and screw. If left behind, these high temp resins may not melt at the next job’s barrel settings.
- Avoiding the use of steel tools while cleaning the barrel and screw.
- Annual inspections for pitting, grooves or discoloration of the screw.
- Annual measurements on the screw, barrel and check ring assembly are logged and compared to previous measurements to determine expected replacement ahead of failures.
- Lubrication is also key. Ensure components such as the screw tip and replaceable nozzles are adequately lubricated with high-temperature-resistant anti-seize. These are necessary to eliminate the chance of breakage during the next removal.
- Monitoring heater band amperage use to ensure the machine is delivering expected energy to each zone.
Investing time and resources into screw and barrel maintenance pays dividends in the form of consistent product quality, lower operational costs, and increased machine longevity. By implementing a proactive maintenance strategy, injection molding facilities can optimize production efficiency and stay ahead in a competitive market. Your injection molding machines are only as good as their most critical components. Prioritize their care, and the results will speak for themselves.