ASACLEAN INJECTION MOLDING PURGING INSTRUCTIONS for High Heat Resins 300°C – 390°C (570°F – 735°F)
Notes before purging:
- ASACLEAN SX should not be left idle in the machine at temperatures that are above 370°C(700°F), for more than 30 minutes as decomposition may occur.
- Keep the barrel full of ASACLEAN SX at all times to prevent oxygen from entering the barrel – excess oxygen will accelerate material decomposition / carbon formation and could potentially result in fire at the higher end of the recommended temperature range.
- To minimize the potential of excessive smoke 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.
- For nozzle hang-up or check ring cleaning (carbon and/or color deposits), please contact your technical sales representative for special instructions.
- Upon completion of the molding operation, run the high heat resin from the machine, emptying the barrel. Purging must begin as soon as possible. Clean the hopper and feed throat. Feed about 1 barrel capacity of ASACLEAN SX Grade into the hopper.
- With the screw completely forward, increase backpressure to a moderate level (enough to keep the screw forward). Note: If processing temperatures are at or near the maximum recommended temperature for the SX Grade, low to medium backpressure and screw speed are recommended. Backpressure and screw speed can be increased at lower temperatures within the recommended range to maximize cleaning.
- Start to extrude the ASACLEAN SX at a slow screw speed. When it starts coming out of the nozzle, increase the screw speed to a moderate level (about 50% of maximum).
- Continue adding ASACLEAN SX following the above instructions until the purge pile is clean.
- After the machine is clean, with the barrel still full of SX Grade, start feeding the next resin to be processed. Displace the SX with the next resin following the same procedure above (using increased backpressure and screw speed with the screw completely forward.
- After all of the ASACLEAN has been displaced, begin production using the normal processing conditions for the resin.