For Resins 175°C – 360°C (345°F – 680°F)

  1. Retract screw and barrel from the mold. Empty the system of the production resin, and make sure the feed areas are clean. Increase the nozzle and front zone heats by 30°C (50°F). Do not exceed 360°C (680°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.

  1. There are two options to add Asaclean PLUS to the system
    1. Blend Asaclean PLUS at prescribed ratio (10-20%) with your next production resin or a low melt injection grade HDPE and feed through hopper.
    2. Asaclean PLUS at prescribed let down ratio through color hopper/additive hopper or a gravimetric feeder.

Do not feed only ASACLEAN PLUS in barrel. It is designed to be used as a mixture with production resin and not by itself in the barrel.

  1. With the barrel now empty and the screw in the forward position, add the purge blend (Asaclean PLUS and next production resin) by rotating the screw until the purge extrudes from the nozzle.
  2. Stop the screw and allow the contents of the barrel to sit for a 10 – 15 minute heat soak with the screw in the forward position. ASACLEAN PLUS is heat activated, so expansion will occur during the heat soak. If nozzle drool stops, jog the screw until it begins again.

Note: if feed throat temperatures exceed 120°C (250°F), turn the screw continuously, at minimum controllable RPM during soak to prevent bridging.

  1. Retract the screw and perform short, high-velocity injection shots
  2. If contamination is still visible as the last of the ASACLEAN PLUS leaves the system, repeat steps 3-5.
  3. Set temperature profile for next production resin to run.
  4. When purging is complete displace the purge blend with the next production resin.
  5. Ensure equipment is at production settings and begin production under normal processing conditions.

Do not allow ASACLEAN PLUS grade to be left idle in barrel for more than 30 minutes at temperatures higher than 300 °C (570 °F).