ASACLEAN PF GRADE INJECTION PURGING INSTRUCTIONS for Transitions from High Heat Resins to Other Resins Above 370°C (700°F) to below 300°C (570°F)
Notes before purging:
- ASACLEAN PF Grade should not be left idle in the barrel for any period of time above 370°C (700°F).
- Keep the barrel full of ASACLEAN PF Grade at all times to prevent oxygen from entering the barrel – excess oxygen will accelerate material decomposition and carbon formation.
- While purging, it is recommended that a bucket of water be kept near the machine. Place ASACLEAN purge piles in water immediately after coming out from the nozzle.
- Upon completion of the production run, extrude the high heat resin from the machine, emptying the barrel. Clean the hopper and feed throat.
- Feed about 1 barrel capacity of the ASACLEAN PF into the hopper, and begin extruding slowly to fill barrel flights.
- Drop the temperatures in the extruder to below 370°C (700°F) – processing temps of 2nd resin – while purging with PF.
- Increase screw speed to maximum safe level, and increase back pressure enough to keep the screw in the forward position. ASACLEAN PF should not be left in the barrel at temperatures above 370°C for any period of time.
- Perform a series of high velocity “short shots” to help clean the nozzle and check ring.
- When all temperatures are below 370°C and the purge pile appears clean, stop screw rotation.
Note: Do not allow melt temps to drop below 280°C (535°F), or undue wear may be placed on the extruder drive.
- When extrudate is clean, and at proper temperature for the 2nd resin, begin feeding 2nd production resin. Once the next resin begins to extrude, increase screw speed to maximum safe level and increase back pressure enough to keep the screw in the forward position.
- Run until ASACLEAN is completely displaced.
- Return to production.