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Density index measuring

Metallic and non-metallic impurities, as well as hydrogen and oxides, may negatively affect the quality of an aluminium melt. By measuring the density index, it is possible to define, control and optimise the process of cleaning the melt, thereby improving the quality. The goal of reducing rejects and thus saving resources (especially personell and energy costs) is made possible by continuous melt monitoring.

mk melt measuring units are used to cast two melt samples to compare the densities: one sample solidifies in a defined vacuum of 80 mbar and the other sample at atmospheric pressure.

The Electronic Density Index Balance MK 3000 automatically determines the specific density of the two samples according to the Archimedean principle and then the density index. The density index represents the percentage difference in density of the produced samples. The lower the density index, the cleaner the melt.

The associated PC software allows the tabular display of individual measurements and measurement series. The standardised comparability, evaluation and archiving of all measurement results is ensured by pre-configured standard report, as is the use for internal and external reporting.

Crucible pre-heating chamber
3VT plus, ALSP plus and ALSP highline include a crucible pre-heating chamber that allows density index samples to always be prepared under the same conditions: 

  • The sample crucibles are always heated to 200°C, to prevent the accumulation of humidity in the crucible coating, which could have a negative effect on the sample.
  • The pre-heated crucible allows the atomically dissolved hydrogen in the melt to develop its full pore potential.