Scale-Up in Co-Rotating Twin Screw Extruders

For scaling extruders similar in design the throughput can be scaled as  

The power consumption in kilowatts (kW) can be determined from N (% torque) (gearbox rating) 

The specific mechanical energy consumption (SMEC) is obtained by dividing the power consumption by the mass flow rate (throughput)  

When the throughput is expressed in kg/hr, the units of SMEC become kW-hr/kg. In scale-up it is often desirable to keep the specific mechanical energy consumption constant. 

If the process is heat transfer limited, the following relationship can be used to determine the throughput of the larger extruder  

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