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Drive System (Moter, Gear Box, Transmission)


Drive Moter :
1. Drive moter provides the torque that turns the screw, and thus provides power to push out the material.
2. DC-Motor are widely used.
3. AC-Motor is used fluctuations in output (surging)  may occur.

  <Gear Reduction And Torque Transmission>
1. The role of gear reduction and transmission is to reduce the motor speed (1750-2000 rpm) to workable screw speed (15-200 rpm) and transfer the motor torque to the screw.
2. For the variation of screw speed over a wide range without reducing it's  torque,  strapless speed changers are used.
3. In the older and smaller extruders,  V belts offered direct coupling,  to transmit the motor torque to the reduction gearbox.
In modern machine the transmission is achieved by direct coupling.

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