Odibert-Arnu apparatus for determination of dilatometric indices.

The operating principle of the apparatus is based on the slow heating at constant pressure of a coal rod (sample,
sample) placed in a dilatometric tube. The apparatus, according to the requirements of the standard,
allows testing of two samples of one sample simultaneously. In this case,
laser sensors, automatically record changes in the volume of coal rods, and the
software builds graphs - delatation curves. At the end of the test
the obtained delatation curves are automatically analysed and determined:
1. softening temperature - t1;
2. temperature of maximum compression (contraction, contraction) - t2;
3. temperature of maximum expansion - t3;
4. maximum compression (contraction) as a percentage of the original length of the sample - a;
5. maximum expansion (delatation curve) in per cent of the original length of the specimen - b.
of the specimen - b.