Injection molding purging procedures for removal of high heat resins for pre-maintenance cleaning using Asaclean PX2 Grade (Above 360°C, 680°F)
- Upon completion of the production run, extrude the high heat resin from the machine, emptying the barrel. Clean the hopper and feed throat.
- Purge out of first resin prior to dropping temps.
Note: ASACLEAN PX2 should not be left idle in the machine for ANY period of time at ANY temperature.
- Feed about 1 barrel capacity of ASACLEAN PX2 into the hopper.
- With the screw completely forward, increase back pressure to the maximum safe level.
- Start to extrude ASACLEAN PX2 at a slow screw speed. When it starts coming out of the nozzle, increase the screw speed to the maximum safe level.
Note: If processing temperatures are at or near the maximum recommended temperature for the PX2 Grade, start with low to medium backpressure and screw speed. Backpressure and screw speed can be increased at lower temperatures within the recommended range to maximize cleaning.
- Set system temps to 315°C – 325°C (600°F – 620°F). Do not allow the temperatures in the barrel to drop below 280°C (535°F) with ASACLEAN PX2 in the barrel as overloading of the screw may occur during rotation.
- Begin feeding ASACLEAN EX into the machine to further remove deposits from the screw and barrel and to make it easier to pull the screw. Follow the standard “ASACLEAN PURGING INSTRUCTIONS for PRE-MAINTENANCE CLEANING and SCREW PULL.” A non-glass filled grade of ASACLEAN, such as ASACLEAN U, can also be used to clean the screw and barrel instead of the EX grade. However, this will not be as effective at removing stubborn deposits.