Monday 13 July 2015
Predicting the performance of processing equipment from measurements of powder properties is an important goal for the powder processing industries. This article describes new collaborative research from Freeman Technology and Gericke to establish predictive correlations for the volumetric flow rate delivered by screw feeders, using dynamic powder testing that can be used to accelerate and optimize screw feeder selection.
In the powder handling industries screw feeders are used routinely to control the flow of material from a hopper into a process. The properties of the powder have a direct impact on the performance of the feeder, making it essential to tailor the design of any given system to the product being handled. A poorly matched powder/feeder combination will typically be associated with low feed rates, high screw torques, and the accumulation of powder on the tube walls. All these factors decrease both short and long term operating efficiency.
This article describes a collaborative study carried out by Freeman Technology (Tewkesbury, UK) and Gericke (Zurich, Switzerland) to identify powder properties that can be reliably measured to predict feeder performance. The work highlights the value of dynamic powder characterization within this context, and concludes with the development of robust models that enable the prediction of feed rate through a screw feeder from flow properties such as Specific Energy (SE), Flow Rate Index (FRI), and Aerated Energy (AE). These models make it easier to select a feeder for a specific powder and predict its likely performance with a high degree of confidence.
Read more in Powder & Bulk Solids.