Powder Flowability and its Importance 

The physical characteristics of the material as well as the particular processing circumstances in the handling system have a direct impact on a powder’s ability to flow. A “single number” used to depict the movement of a powder may not be practical or may not provide enough information for such a complicated system. Physical characteristics like particle size, size distribution, shape, surface area, and density affect how powders flow.

Anybody who works with powders is aware that when a substance is transported from one environment to another, its flow characteristics can quickly alter. Temperature, humidity, electrostatic charge, and time are just a few of the environmental factors that can have a significant impact on flow during processing, handling, or transport. This is why it’s important to test under various conditions to determine how a powder will behave under various processing scenarios. Infinita Lab can assess a number of these variables for client content.

Powder Rheometer is a versatile powder tester that can detect wall friction as well as dynamic, bulk, and shear properties. Several powder “states” can be measured using various testing methods, including dynamic, static, and under-stressed conditions.

This device employs a novel method for testing powder. By running a blade through a sample of conditioned powder under various testing conditions, the device calculates the amount of energy required to produce particular flow conditions. While compacting the sample into a container or entraining air during transfer can have a significant impact on powder flowability, the    testing methodology includes tools to assess and control these situations. Moreover, the techniques lessen operator-contributed handling variability. The end effect was increased data accuracy and repeatability.

Typically, a powder flowability study involves testing the material, with the results being presented graphically and numerically. The powder’s flow properties in three different packing conditions are among the data given.

Aerated, conditional, and combined

In this way, a comprehensive understanding of flow in various processing environments is given. Testing in particular comprises:

Stability: At the same blade speed, how repeatable is the flow of energy?

Variable Flow Rate (How does the energy of the flow change as the blade speed is lowered?)

Aeration and Deaeration: How do the flow energy and air velocity through the powder bed change?

Compaction (How would you compare the modes of consolidation of tapping and direct pressure?)

Permeability: How easily does the powder allow air to travel through it?

Compressibility (How does the bulk density alter in response to a downward compaction force)

The following tests may be helpful in addition to the aforementioned standard Powder Flowability Study, although they come at an additional cost. For instance, flow from a hopper or silo could benefit from the following processing conditions:

Shear Cell Testing: How much force is required to start a flow of a powder in a consolidated or stressed state?

Testing for Wall Friction: What effects do different polished metal surfaces have on the flow energy of the powder when they come into touch with it?

Several customers in the pharmaceutical, automotive, cement, cosmetic, and industrial sectors have found the  Powder Rheometer’s adaptability to be useful. Please get in touch with us to talk about how the  Powder Rheometer might help offer more answers to your issues about managing powder.

Advantages

• Permits a variety of testing scenarios to investigate environmental effects
• Provides reliable, consistent data
• The capacity to assess processing conditions using wall friction and shear cell testing
• Pre-conditioning samples are supplied for time, temperature, and relative humidity.

Considerations

• Historical data enables comparison between samples.
• There are ways to finish traditional flowability approaches for the angle of repose, tap density, bulk density, and flow via an orifice.
• When conducting the Powder Flowability Research at Infinita Lab, physical characteristics that can affect flowabilities, such as particle size, shape, surface area, and density, can all be examined.

Video 01: Powder Flowability