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Thrust Bearing

Thrust Bearing -
The screw fits into a thrust bearing located behind the feed hopper.
The function of the thrust bearing is to absorb the thrust force acting on the screw inside the extruder barrel.
1. The bearing prevents  the screw from moving  backward .
2. Bearing life-time depends on the pressure and screw speed. For high speeds, oversized being is needed.
3. For twin screw extruders several smaller bearings joined in one shaft is used.
(Thrust Force = Extrusion Pressure X Cross Sectional Area of the screw )

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