Injection Molding Hot Runner Purging Instructions | Asaclean


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Hot Runner Cleaning with Mechanical Grade - Open Mold Method

Precautions

  • Only use an Asaclean® grade approved for use in hot runners and rated for the minimum clearances in your system.
  • External heating systems - Raise the manifold temperature 20-30°C (35-55°F) for improved flow. If running heat-sensitive resins, do not exceed the maximum safe operating temperature of the material.
  • Internal heating systems - Consult Asaclean® for technical assistance before using.
  • If available, apply mold release agent to reduce the potential for material sticking to the mold surface.
  • Preparation: The entire Hot Runner System temperature must be within the temperature usage range of the Asaclean® grade to be used.

Purging with Mold Plates Open

  1. After the screw and barrel have been cleaned thoroughly using Asaclean®, seat the nozzle into the mold.
  2. Open the mold plates.
  3. Set up a Safety-approved surface for collecting the purgings.
  4. Verify that the mold safety door is closed.
  5. Add enough Asaclean® into the hopper to fill the barrel approximately ½ full.
  6. Extrude Asaclean® through the hot runner system starting at a medium velocity. Increase screw speed to the maximum safe level for maximum cleaning. Once Asaclean® is flowing adequately through all the gates, perform injection shots (air shots) with mold plates open.
  7. Visually-inspect purgings for color and/or carbon contamination.
  8. If color and/or carbon still remain, repeat step 5 through 7 until the Asaclean® is visually free of color and/or carbon contamination and has returned to a clean appearance.
  9. Purge out any remaining Asaclean® using the maximum safe screw speed. Adjust the temperatures in the barrel and hot runners to the processing conditions for the next resin to be processed.
  10.  Flush the system with the next resin to be processed using the maximum safe screw speed until the next resin is visually free of the Asaclean®.
  11. Resume production using normal production settings.  

Exercise proper safety precautions and use appropriate PPE.

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

Hot Runner Cleaning with Mechanical Grade - Closed Mold Method

Precautions

  • Only use an Asaclean grade approved for use in hot runners and rated for the minimum clearances in your system.
  • External heating systems - Raise the manifold temperature 20-30°C (35-55°F) for improved flow. Do not exceed the maximum safe operating temperature of the material.
  • Internal heating systems - Consult Asaclean® for technical assistance before using.
  • If available, apply mold release agent to reduce the potential for material sticking to the mold surface.
  • Preparation: The entire Hot Runner System temperature must be within the temperature usage range of the Asaclean® grade to be used.

Purging with Mold Plates Closed

  1. After the screw and barrel have been cleaned thoroughly using Asaclean®, seat the nozzle into the mold.
  2. Verify that the mold safety door is closed.
  3. To reduce the small possibility of Asaclean® parts getting stuck in the cavities, reduce cooling time and spray the cavities with mold release.
  4. Remove pack and hold pressures and velocities. Inject Asaclean® using short-shot molding (use only as much shot as is needed to safely remove parts from the cavities - no more than 90% shot size).
  5. Eject parts immediately, while they are still warm.
  6. Visually inspect parts for color and/or carbon contamination until parts are clean.
  7. If color and/or carbon still remain, repeat step 4 through 6 until the Asaclean® is visually free of color and/or carbon contamination and has returned to a clean appearance. Purge out any remaining Asaclean® using the same method as above. Adjust the temperatures of the barrel and hot runners to the processing conditions for the next resin to be processed.
  8. Flush the system with the next resin to be processed, molding parts until Asaclean® can no longer be seen in the next resin.
  9. Resume production using normal production settings.

Exercise proper safety precautions and use appropriate PPE.

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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