Flow Properties Of Bulk Solids

Flow Properties Of Bulk Solids .

Flow Properties of Bulk Solids  

Technical Description of Flow Properties of Bulk Solids 

The flow properties of a powder or bulk solid determine how it behaves during handling. For example, material may flow irregularly out of silos, or the flow of bulk solid may come to a stop. In order to avoid these problems in practice, silos can be designed on the basis of measurements using shear testers, such as the Jenike shear tester or a ring shear tester. In a ring shear tester, a bulk sample is contained in a ring-shaped shear cell. A normal force is exerted on the sample by way of a lid. A hanger from which a variable weight is suspended generates this normal force. A motor moves the shear cell relative to the lid in order to apply shear to the sample. For compaction (pre-shearing) the sample is subjected to a large normal force. An electronically amplified force transducer measures the shear forces which are then recorded by data acquisition software over time. After pre-shearing, shearing to failure is executed with a reduced normal force (strength measurement) and likewise recorded by the software. From the shear force characteristics, properties such as the compressive strength and internal friction of the bulk solid can be determined. To determine the density of the bulk solid, the volume of the bulk sample is ascertained by recording the lowering of the lid using a vernier caliper gauge.

Specification of Flow Properties of Bulk Solids  

• Design of bulk solids silos using a ring shear tester
• 1 ring-shaped shear cell to determine yield loci
• 1 ring-shaped shear cell with sample of wall material to determine wall yield loci
• Shearing of the bulk solid sample by motor rotation of the shear cell
• Vertical loading of the sample via ring-shaped lid with weights
• Force sensor to measure the shear forces
• vernier caliper gauge to measure the change in height and density of the bulk sample
• Evaluation software to determine the relevant bulk solid parameters

Technical Data of Flow Properties of Bulk Solids              

Shear cell

• Sample volume: approx. 70cm3
• Material: aluminium

Shear cell with sample of wall material

• Sample volume: approx. 15cm3
• Material: aluminium

Motor

• Power consumption: max. 75W
• Speed: 500...3.000min-1

1 set of weights

• 4x 500g
• 2x 200g
• 2x 100g
• 2x 50g

Measuring ranges

• Shear force: 0...40N
• Balance: 0...1.000g

Dimensions and Weight of Flow Properties of Bulk Solids           

• LxWxH: approx. 550x300x450mm
• Weight: approx. 30kg