At Interphex 2006 (March 21-23, 2006; New York), Freeman Technology will introduce a permeability module for the company's FT4 powder rheometer
The permeability of a powder is a measure of the ease with which air can pass through it under specified conditions.
It has considerable significance in relation to powder processing, especially the influence that it exerts on a powder's ability to entrain and release air.
These characteristics can greatly affect flow behaviour and process efficiency.
The FT4 powder rheometer is a fully automated universal powder tester for the comprehensive characterisation of powder flowability.
The new permeability module uses a pressure transducer to measure pressure drop across the height of a powder bed in the system's test vessel while the air velocity through the powder is controlled.
Importantly, conditioning of the sample before evaluation ensures a homogeneous, stress-free and reproducible packing condition.
Permeability measurements using the FT4 can be conducted in a variety of ways to suit specific requirements.
These include: measuring pressure drop versus air velocity at zero bed compression stress; using a porous piston to apply specific compression stresses to the sample while maintaining a fixed air velocity through it and measuring pressure drop as a function of the applied bed compression stress; or maintaining a specific bed pressure drop and measuring the air velocity versus bed compression stress.
The FT4 Program Editor allows construction of all the above testing programs and variants of them.
Once started, the entire test sequence runs automatically.
Comprehensive data analysis enables the rapid production of graphical representations of all the measured data.
