BULK DENSITY AND ELECTRIC RESISTANCE UNDER PRESSURE
ASTM D4164 | ASTM D4781
The determination of the relationship between powder bulk density and applied pressure provides relevant information for the optimization of tableted materials like carbons, ceramics and catalysts.
Cylindrical Sample Container
Both DENSIPRESS and DENSIPRESS/R are equipped with a cylindrical sample container (diameter 20 mm, length 250 mm), where the powder is loaded. Copper cylinders with different lengths allow to change the sample volume. The sample container, Teflon-lined in DENSIPRESS/R, can be detached from the basement for easier removal of the powder. In DENSIPRESS/R two wired copper disks placed at the bottom of the piston and of the sample container allow to measure the electrical resistance of the powder through an ohmmeter.
Before testing, the bulk density of the powder shall be measured in a glass cylinder with the same diameter as the sample container, following exactly the same procedure used for loading. The height of the powder in the sample container can thus be calculated from the previously measured bulk density.
Then the piston is shifted up to the upper level of the powder, readable on the graduated bar. By means of two wheels (coarse and fine) the piston is displaced down at suitable intervals and each time the piston level (graduated bar) and the applied load (digital display) are noted. It is advisable to wait a few minutes before reading the value of the applied load to allow any compressed air to leave the sample container.
The relation between the bulk density (from the volume occupied step by step by the powder and its weight) and the applied pressure (from the load and the section of the sample container) can therefore be determined.
For the measurement of the electrical resistance, an ohmmeter (included in the equipment) is connected to the two copper disks terminals.
Size (W x H x D)
200 x 820 x 250 mm
150 kg (other values upon request)
blue and black
Typical max applied pressure
Max useful sample volume
RS232 PC connection