Automated Measurement of Powder Flow Rates Through Apertures – GranuFlow

The GranuFlow is an enhanced version of laboratory silo when compared to the “Flow-Through An Orifice” technique explained in the Pharmacopeia (USP1174) and the traditional Hall Flow Meter (ASTM B213, ISO4490).

GranuFlow features a rotating plate with seven different holes ranging from 1 to 38 mm in diameter and also a 500 mL-capacity stainless-steel cell. As the measurement takes place, the diameters of holes are manually increased. The mass flow rate of powders is automatically measured by a dedicated electronic balance without user interference.


The mass flow rate is calculated automatically from the slope of the mass temporal evolution quantified with the balance. Using an original rotating system, the aperture size is altered easily and rapidly. Both measurement and result analysis are aided by software. The flow rate is measured for different sizes of the aperture to obtain a flow curve. The entire flow curve is finally fitted with the popular Beverloo theoretical model to achieve a flowability index (Cb, related to the powder flowability) and the minimum aperture size to achieve a flow (Dmin). The entire measurement is carried out in a simple, accurate, and rapid manner.

Key Benefits

  • The measurement of mass flow through different holes does not need any cleaning and disassembling of the instrument
  • In order to fulfill a broad array of cell capacities, the configuration of the GranuFlow can be adjusted


  • The only automatic funnel flow meter available in the market
  • Precise, quick (less than 5 minutes for the whole Beverloo curve calculation [1]), and highly reproducible results (2% of accuracy, without depending on users)
  • The minimum drain diameter of the tested material can be estimated accurately
  • Interpretation of intuitive results; robust and can be maintained easily
  • Precisely measures the flowability of powders through a complete range of holes at once
  • Supplied with intuitive software, which enables the comparison of results. The entire data are automatically collected and stored for post-processing. Data can be easily transferred and reports can be automatically generated.


  • Enables rapid and precise test for a production line, and moreover, problematic samples can be detected prior to introducing them inside the silo
  • Classification of  powder flowability for the galenic formulation
  • Measurements of powder flowability in a silo-funnel geometry


  • Includes a calibration kit
  • Standalone version including an electronic display and an ultrasonic sensor for heavy-duty environments
  • Additional rotating plates for low- and high-cohesion powders

[1] So-called cup tests take approximately 30 minutes, and it is not possible to obtain the Beverloo Law with the Hall flowmeter.

Automated Measurement of Powder Flow Rates Through Apertures – GranuFlow

GranuFlow - Picture 1
GranuFlow - Picture 2
GranuFlow - Picture 3
GranuFlow - Picture 4
GranuFlow - Picture 5

Other Equipment by this Supplier