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Single screw extruders (SSE)

√ The Single Screw Extruders is a relatively inexpensive machine for small or medium size production lines.
√ For line with the throughput exceeding 10 tons per hour (10/h), the capital costs of SSE and TSE are comparable. SSE that can produce 40 Tons/hour can be custom-built only few manufacturers.
√ The Single-Screw Extruders consist of screw rotating in heated barrel or cylinder to which the material is fed.
  1. Feed hopper. (click here)
  2. Extruder Screw and Barrel .(click here)
  3. Drive system (motor,  gear box,  transmission).(click here)
  4. Thrust Bearing.(click here)
  5. Heating and Cooling Elements.(click here)
  6. Screen pack and Breaker plate.(click here)
  7. Die .(click here)
  8. Temperature and pressure  controls.




•Single Screw Extruders parts and function-(in short notes)
1. Screw Pump :   Combination of screw &Barrel
2. Hopper :   Funnel like device,  mounted on hopper throat. Holds a constant reserve of material.
3. Barrel :   Cylindrical housing in which the screw rotates.
4. Hopper Throat :   Circular opening at the feed end through which the material enters the screw pump.
5. Drive System :    AC/DC drives,   Speed reduction Gear box  Transmission system.
Definition of terms :
√ Compression Ratio - Is the ratio between the channel depths is the feed zone to that of the metering zone.
  Usually from 1.5 to 4:1
√ L/D ratio -  Length of nominal dia of screw , Usually 20 to 22:1
Important Specification :
√ Nominal dia of screw
√ Output  (kgs/hour)

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