Measuring the physical properties of powders and bulk solids
Benefit from more than thirty years of experience in bulk solids analysis. All measurements are carried out professionally in our laboratory on standardised, certified instruments. You receive real physical material data – needed to characterise your bulk solid and as the basis for further technological calculations.
Measured material data are the key to safe applications.
Designing silos safely, comparing bulk solids reliably
Wherever bulk solids are stored and handled, measured bulk solid properties are the reliable basis for safe characteristic values – instead of table values or estimates.
- Silo calculations and actions on silos to DIN EN 1991-4
- Comparing the flowability of bulk solids
- Technological design of silos and bulk solids containers
- Checking dischargeability when changing products or introducing new bulk solids
- Preventing arching during silo discharge
- Selecting suitable wall materials to improve dischargeability
- Troubleshooting existing plants – finding the causes of flow problems
- Designing silos for mass flow
- Avoiding problems caused by time consolidation during storage and transport
- Comparing rheological properties at different moisture contents
- Quality control and product certification – specifying flow properties and incoming goods inspection
- Optimising flow aids and processes
- Process control to prevent operational disruptions and damage
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Mass flow The entire bulk solid is in motion – what goes in first comes out first.
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Funnel flow Only a core flows; dead zones remain at the hopper walls – segregation and ageing.
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Ratholing Only a stable channel above the outlet empties; the rest stays in the silo.
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Arching A stable arch above the outlet stops discharge completely.
- Chemicals
- Pharmaceuticals
- Food
- Animal feed
- Cosmetics
- Building materials
- Plastics
- Metal powders
- Minerals
- Recycling
- Biomass
Rheological and physical bulk solids measurements
Digital and connected throughout: our instruments pass their measured values to the evaluation automatically, without manual transfer – from sample preparation to the finished result. You receive everything online, ready to use.
| Measurement | Method, parameters |
|---|---|
| Yield locus | angle of internal friction φi, effective angle of internal friction φe, cohesion τc, horizontal load ratio λ and λ0, unconfined compressive strength σc, flowability factor ffc (FL, FLA, FLR), flow density ρbr(σr) + optional time consolidation |
| Wall friction | wall friction angle φw, wall friction coefficient μw, adhesion τw + optional time consolidation |
| Compression density | density function ρb(σ) |
| Bulk density | bulk density ρb0 to EN ISO 60 or USP 616 III |
| Moisture content | oven-drying method (drying oven, 105 °C) or halogen moisture analyser: %M (percent moisture), %S (percent solids) |
| Angle of repose | angle of repose to DIN ISO 4324 or ASTM D6393 |
| Sieve analysis | dry sieving in a sieve tower (DIN 66165) after drying at 105 °C: particle size distribution from 63 µm to 2 mm (10–240 mesh), from fine powder to fine granules; passing < 63 µm as fines |
From measured values to a basis for calculation
Every measurement automatically yields the functions, comparisons and calculations you continue to work with – consistent, reproducible and comparable across many batches.
Evaluation of every measurement
- Measured values, parameters and diagramsEvery measurement fully evaluated – traceably documented and ready to use.
Further evaluations
- Bulk solids functions from combined measurementsFlow function, density function and effective angle of internal friction across the whole measured stress range – the flow behaviour of your bulk solid at a glance.
- ComparisonsSeveral samples, batches or suppliers side by side – so you see which parameters make the difference in flow behaviour.
All results in the customer portal
Measured values, evaluations and diagrams are available online – accessible at any time, several samples shown together for comparison, and as a PDF to pass on.
Basis for the silo calculation
- All material parameters to DIN EN 1991-4Mean values of the unit weight γ, the angle of internal friction φi, the lateral pressure ratio K and the wall friction coefficient μ, together with the conversion factors aγ, aφ, aK and aμ for the upper and lower characteristic values.
- Calculation as a design aidSilo loads, the limit criterion for mass and funnel flow and the critical outlet diameter – as a basis for placing the measurement results correctly and designing the silo properly.
How a measurement works
From enquiry to review – in five steps.
- Enquiry Describe your bulk solid and your question in the form.
- Quote An individual quote with the measurements that fit.
- Send your sample Send us your material sample, under NDA on request.
- Measurement & report Measured values, evaluations and silo calculation as a PDF.
- Review Results and recommendations explained in person.
What customers ask before their first measurement
- How long do the measurements take?
- Results are usually available about two weeks after sample receipt – depending on laboratory capacity and the number of samples. Time consolidation tests can extend the standard lead time accordingly.
- How much sample material do you need?
- About 1 to 2 litres per sample for a complete bulk solids analysis for silo calculation; 0.5 litres is enough for a flowability factor measurement alone. The sample should be representative of the whole material.
- What is the maximum particle size?
- For a standard-compliant measurement the material should not exceed a particle size of 2 mm. For coarser particles we assess the feasibility together with you.
- Which silo details do you need?
- Approximate figures are sufficient for the reference stresses: silo shape and dimensions, height of the vertical section, hopper inclination relative to the vertical, hopper height or outlet diameter, wall material and approximate density.
Professional contract testing for powders and bulk solids
Do you need reliable parameters for your bulk solid? Describe your question – we put together the right measurements and prepare a non-binding quote for you.
- Expert advice on choosing the measurements
- Results about two weeks after sample receipt
- Measured values, evaluations and silo calculation online and as a PDF
- Personal support and review of the results
- Recommendations for putting them into practice