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Barrel & Hopper Cooling System (Elements) :

                   :Barrel Cooling :
1. Barrel cooling is needed to prevent overheating that may cause degradation.
2. For small extruders fans that blow air over or around the barrel are used.
3. Other cooling system used include .
4. Cooling channel inside the barrel wall.
5. Find on the barrel or on the heaters to speedup that transfer.
6. A watet-fog spray over barrel.
7. Continuous, controlled vaporization of liquid (water)
8. Copper tubing carrying cold water is sometimes used.
              *Hopper Cooling Systems*
• Water-cooling is used to cool the hopper throat to prevent bridging and to protect the rubber parts present in the screw support  assembly.

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