Simple Dewatering and Torque Scale-Up

While the majority of applications will be scaled by Sigma, there are occasions when high conveyor torques are experienced during test work. Then it will be necessary to scale the torques experienced, to the proposed larger machine, not only to ensure that this will not be limiting but also to estimate the power required for the drive motor. 

Some dry solids applications (covered in Section 7.9) will have their capacities limited by gearbox torque rating. When scaling these applications to larger decanter sizes, it is important that the torque rating available is greater than the scaled-up torque. 

As an example, these torque data will be scaled to a decanter of 737 mm bowl diameter. Data  

Firstly the bowl speed for the larger machine needs to be calculated, assuming that it will need to have the same g-level as the test machine. For the test machine, bowl speed  

The feed rate will be scaled by Sigma, which thus needs to be calculated for each machine, using equation (4.32). For the test machine. Sigma  

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