Getting the Most Out of CELPURGE
Backpressure in Injection Molding Machines
One method commonly used to purge injection molding machines involves applying backpressure to discharge the purging compound from the nozzle. However, this method is not very effective when using CELPURGE. Rather, the most important point when cleaning injection molding machines with CELPURGE is to not apply backpressure.
In order to achieve superior self-purging performance, CELPURGE includes components that generate a powerful “expansion action.” The key point in maximizing this expansion is to not apply backpressure and to not flush CELPURGE, so that it can lift off the contaminations adhering to metal surfaces. Naturally the application of backpressure does have a cleaning effect, but in this case results in unnecessary consumption of purging compound.
The method of “applying backpressure to discharge the purging compound from the nozzle” may be an effective one for the semimolten type compounds. Semimolten types are frequently used due to their ability to scour away deposits, but have the disadvantage of being difficult to be purged.
Applying backpressure to flush CELPURGE from the nozzle: difficult to remove Contamination with scouring action alone
Without applying backpressure, CELPURGE is not flushed from the nozzle: Contamination lifted off through “expansion action”
Setting Up the Molding Machine
Here we show you a standard setup for cleaning of a molding machine. Please also refer to the page of “Recommendable Cleaning Process.” For performing the standard cleaning, consecutively perform the “1st Cleaning/Basic Cleaning” and the “2nd Cleaning/Nozzle Cleaning.” By performing the cleaning in two stages, you can minimize the amount of CELPURGE used and save money.
1st Cleaning/Basic Cleaning
- metering position : 70% of maximum
- Number of shots : 5 –10 shots
- Screw rotation speed : 70% of maximum
(Be sure that torque is not too high.)
- Injection pressure : 70% of maximum
- Injection speed : 70% of maximum
2nd Cleaning/Basic Cleaning
- metering position : ca. 30mm
- Number of shots : > 15 shots
