ASACLEAN™ NCF GRADE EXTRUSION PURGING INSTRUCTIONS For Resins 175°C – 290°C (345°F – 555°F)
- Empty the system of the production resin, and make sure the feed areas are clean. Do not remove the die.
- If possible, and safe, increase temperatures in all zones after the extruder by 55⁰C (100⁰F) above production temperature, but do not exceed 290⁰C (555°F).
If purging a heat sensitive resin, do not exceed the safe processing temperature of the material. This purge procedure may need to be repeated at elevated temperatures to remove all contamination.
- Flush the machine by running 1-4 system volumes of clean, natural polyethylene that is at least as stiff as the production resin. Run system empty.
- Add Asaclean NCF at normal screw speed until the purge extrudes uniformly from the die.
- Soak the system with the screw turning at minimum controllable rpm for 20-30 minutes (if sealing, turn off all heaters with the system full of Asaclean NCF).
- Purge the machine of the Asaclean NCF at normal screw speed.
- If contamination is still visible as the last of the NCF leaves the system, repeat steps 4-6.
- Set temperature profile for next resin to run.
- Wait 5 minutes with an empty barrel for the Asaclean NCF residue to break down.
- When safe, displace the Asaclean NCF with the next resin.
- Begin production under normal processing conditions.