At the Particulate Systems Analysis (PSA 2008) conference and exhibition (2-4 September 2008, Stratford on Avon, Warwickshire, UK) Reg Freeman, Managing Director of Freeman Technology, will present the results of a new study, ‘Measuring powder characteristics relating to forced flow into confined spaces using a universal powder tester’. The work was performed using the company’s FT4 Powder Rheometer. This universal powder tester enables the independent assessment of factors affecting powder flowability, providing improved quality and control to powder processing industries.
Very cohesive powders tend to behave more like fluids when pressurised or subjected to forced flow. The study focuses on understanding these characteristics, and determining how they correlate with known powder flowability parameters that describe dynamic flow behaviour, shear properties and bulk properties, including permeability and compressibility.
Powder extrusion, flow in confined spaces and the normal stresses generated when powders are sheared, are all examined. A number of different powder types are evaluated, including cohesive powders like CRM-116 limestone, free flowing powders such as spray dried and coarsely milled lactose, and calcium sulphite hemihydrate. The ways in which particle size, shape, texture and flow agents affect powder behaviour is also studied.
The FT4 Powder Rheometer provides comprehensive powder flowability data that can be correlated with processing experience to aid efficient processing and quality control. It provides automated shear testing, dynamic flowability and bulk properties measurements making it a universal powder tester for formulators, process engineers and QA specialists.