PF Grade | Temperature Change Injection Purging Instructions


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Asaclean® PF Grade Injection Purging Instructions for Transitions from High Heat Resins to Other Resins Above 370ºC (700ºF) to below 300ºC (570ºF)

Notes Before Purging

  • Asaclean® PF Grade should not be left idle in the barrel for any period of time above 370ºC (700ºF).
  • 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® PF Grade purge piles in water immediately after coming out from the nozzle.
  1. Upon completion of the production run, extrude the high heat resin from the machine, emptying the barrel. Clean the hopper and feed throat.
  2. Feed about 1 barrel capacity of the Asaclean® PF Grade into the hopper, and increase screw speed to maximum safe level, and increase back pressure enough to keep the screw in the forward position. Asaclean® PF Grade should not be left in the barrel at temperatures above 370ºC for any period of time.
  3. Perform a series of high velocity “short shots” to help clean the nozzle and check ring and make sure the purge pile appears clean
  4. Drop the temperatures in the barrel under slow screw speed to below 370ºC (700ºF) – processing temps of 2nd resin – while purging with Asaclean® PF Grade.
  5. When all temperatures are below 370ºC, stop screw rotation.

    Note: Do not Asaclean® PF Grade allow melt temps to drop below 280ºC (535ºF), or undue wear may be placed on the extruder drive.

  6. The processing temps of 2nd resin →280ºC -300ºC (535ºF-570ºF): When all temperatures are 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® PF Grade is completely displaced. The processing temps of 2nd resin→180ºC -280ºC (355ºF-535ºF): When all temperatures are at 300ºC (570ºF), extrude Asaclean® PF Grade form the machine, emptying the barrel, as far as possible. And feed about 1 barrel capacity of the Asaclean® U Grade into the hopper. And keep the barrel full of Asaclean® U Grade. Drop the temperatures in the extruder to processing temps of 2nd resin. When all temperature are at processing temps of 2nd resin, feed about 1 barrel capacity of the Asaclean® U Grade into the hopper and increase screw speed to maximum safe level, and increase back pressure enough to keep the screw in the forward position. And extrude Asaclean® U Grade form the machine, emptying the barrel, as far as possible. And Feed 2nd resin and use low back pressure and screw speed until the next resin starts coming out from the nozzle, then increase to moderate back pressure and moderate screw speed until all of the Asaclean® U Grade is completely displaced.
  7. Return to production.

Technical questions? 

To request detailed technical bulletins or technical support, contact us at Asahi Kasei Plastics North America Inc.

Phone: (800) 787-4348 / (973)257-1999
Fax: (973) 257-1011
Website: www.Asaclean.com
E-mail: sales@Asaclean.com

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