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GranuDrum Now Defined by an ASTM Standard: ASTM D8648‑25
Standardization is a key element in powder characterization, as it ensures reproducibility, comparability between laboratories, and confidence in measured data. This is especially critical when powder flowability directly impacts industrial processes.
We are pleased to announce that GranuDrum is now covered by an official ASTM standard: ASTM D8648‑25 – Standard Test Method for Determining Flowability Using GranuDrum. This publication represents an important milestone in the standardization of dynamic powder flowability measurements using a rotating drum method.
Why an ASTM Standard Matters
Granular materials and fine powders are widely used in industries such as pharmaceuticals, additive manufacturing, batteries, chemicals and food processing. Their behavior during handling, transport or processing depends strongly on flow properties, which can be difficult to characterize using static methods.
ASTM D8648‑25 provides a recognized and standardized methodology for measuring powder flowability using the GranuDrum. By defining the test apparatus, procedures and data interpretation, the standard enables meaningful comparison of results obtained across different laboratories and organizations.
Scope of ASTM D8648‑25
The standard applies to powders and bulk solids with a maximum particle size of 2 mm and is typically used for materials in the 1 to 400 µm range. It defines the measurement of several key flow-related parameters, including:
- the dynamic angle of repose (also referred to as the flowing angle),
- the dynamic cohesive index,
- the first avalanche angle,
- and powder aeration.
These parameters are commonly used to compare powders, assess the impact of formulation or processing changes, and support numerical simulations such as Discrete Element Method (DEM) modeling.
A Standardized Rotating Drum Method
ASTM D8648‑25 formally describes the GranuDrum technique as an automated rotating drum method. A powder sample is placed in a horizontal drum and rotated at controlled speeds while a camera captures the powder-air interface. Image analysis is then used to extract both the average surface profile and its fluctuations over time.
This approach provides access not only to flow angles but also to cohesion-related properties that are difficult to quantify using traditional static tests.
Reliability and Good Laboratory Practice
The standard emphasizes that the quality of the results depends on operator competence, instrument suitability and controlled environmental conditions. It explicitly refers to ASTM Practice D3740, underlining the importance of consistent procedures and qualified testing laboratories.
What This Means for GranuDrum Users
For GranuDrum users, ASTM D8648‑25 provides a clear and internationally recognized reference method for reporting powder flowability results. It strengthens confidence in the measurements, facilitates comparison between organizations, and supports use in industrial, academic and regulatory contexts.
Moving Powder Flow Characterization Forward
The publication of ASTM D8648‑25 reflects a collective effort to improve the reproducibility and transparency of powder flow measurements. It confirms GranuDrum’s role as a reference technique for dynamic powder flow characterization and provides users with a robust standardized framework to better understand and control powder behavior.