.jpg)
Topics Covered
Background
Powder Testing Using Energy Measurement of Specific Flow Conditions
Importance of Shear and Bulk Properties
Improving Manufacturing Efficiency with Powder Rheometer System
Operating Principle of Powder Rheometer
Universal Powder Tester - The FT4 Powder Rheometer
Accessories for Powder Rheometer
Optimal Approach for Powder Assessment
Features of FT4 Powder Rheometer
Background
Freeman Technology is a specialist company pioneering the measurement and understanding of powders and their flow properties. Founded in 1989, the company developed the novel, patented technology that forms the core of its Powder Rheometer system at its design and manufacturing centre in Worcestershire, UK where all manufacturing takes place in an ISO 9001:2008 accredited environment. Research into understanding powder behaviour is central to the company's business strategy.
Freeman Technology's business is researching powder behaviour and designing instrumentation for powder characterisation. The FT4 Powder Rheometer is a universal powder tester that is really three instruments in one – combining a powder rheometer with a shear cell capability and a compression tester. This allows comprehensive characterisation of powders of all types, reflecting the complexity of powders in contrast to traditional single number assessments of flowability.
Powder Testing Using Energy Measurement of Specific Flow Conditions
The patented rheometer methodology provides a totally innovative approach to powder testing by measuring the energies needed to establish specific flow conditions. Major benefits include high sensitivity and the ability to evaluate all packing states, whether consolidated, non-consolidated, aerated or even fluidised. The shear methodology is represented by three sizes of shear cell, the smallest requiring only 1ml of powder. Other measurements include compressibility and permeability, the later using the Aeration Module – an automated mass air flow controller that is used primarily to determine how aeration affects flowability. To ensure exceptional reproducibility all testing methodologies use the unique conditioning process to normalise powder samples prior to testing.
Importance of Shear and Bulk Properties
The data derived from measuring dynamic flowability, shear and bulk properties have many applications. Central to all is establishing for any given process or process step, the properties of powders that flow well in contrast to those that do not. Correlation of powder properties with processability is the key to informing formulators on what works well, manufacturers on how to trouble shoot and optimise production, and quality control specialists on how to determine QC criteria.
Improving Manufacturing Efficiency with Powder Rheometer System
The FT4 Powder Rheomete allows the considerable processing experience that most companies have to be categorised and used as a reference for anticipating and resolving future difficulties. The key benefits of this will be continuous improvements of both manufacturing efficiency and control of product quality.
.jpg)
Operating Principle of Powder Rheometer
It is easy to imagine stirring a powder sample using a spatula or even a finger and feeling the resistance as the powder is made to flow. The FT4 Powder Rheometer operating principle uses a sophisticated finger in the form of a precision twisted blade that is forced through the powder bed. It moves along a predetermined helical path so that a required flow rate and pattern of flow is established. The forces causing the deformation and flow of the powder are those imposed by the moving blade and these are measured continuously and used to calculate the energy needed to make the powder flow. This methodology therefore measures ‘flow energy’ and is described as the ‘Dynamic flow’ methodology because the flow pattern is three dimensional and representative of real flow conditions.
Universal Powder Tester - The FT4 Powder Rheometer
The FT4 Powder Rheometer is a universal powder tester - three instruments in one, combining the Freeman Technology patented blade methodology for measuring flow energy with a range of shear cells, wall friction modules and other accessories for measuring bulk properties. The methodologies allow measurement of:
- Flow energy in relation to many variables and all packing states
- Shear properties of consolidated and unconsolidated powders
- Bulk properties – precision bulk density, compressibility and permeability
- Process variables such as moisture, attrition and segregation
Accessories for Powder Rheometer
The system accessories available for FT4 powder rheometer include:
- Three sizes of testing vessel: 25, 50 and 62mm diameter for different samples sizes.
- Aeration Control module to aerate/fluidise powder samples
- Compaction accessories for consolidating powder
- Shear cell modules – three sizes down to the 1ml cell
- Wall friction modules to measure powder on metal interaction
.jpg)
The above methodologies and System accessories allow powder samples to be comprehensively characterised for the extremes of packing and environmental conditions that occur in everyday processing.
Optimal Approach for Powder Assessment
The optimal approach for powder assessment is firstly to use testing methodologies that provide reproducible data and secondly to evaluate flow performance in ways that relate to powder behaviour in real industrial processes. This means quantifying the effects of consolidation, vibration, segregation, moisture uptake, fines, aeration, flow rate, air entrainment and a number of other factors. Such characterisation using complementary methodologies has wide application in the formulation, processing and QC sectors of most powder processing industries.
Features of FT4 Powder Rheometer
The features and benefits of the FT4 powder rheometer are outlined below.
- Three instruments in one – rheometer, shear cell and compression tester
- Powder conditioning that allows exceptional reproducibility of measurement
- Automated testing and analysis - independent of the operator
- Quick and straightforward operation- tests completed in minutes
- Ability to evaluate consolidated, conditioned and aerated / fluidised powders
- Unique measurement of aeratability of powders
- Small volume of sample - down to 1ml in the case of the miniature shear cell
- Three test vessel standards - 25, 50 and 62mm diameter for different sample volumes
- Family of three shear cells, 80, 10 and 1ml capacities
- High sensitivity dynamic mode for differentiating between very similar powders
- Can evaluate process variables such as attrition and segregation
Source: FT4 Powder Rheometer System
For more information on this source please visit Freeman Technology