pyrometric cone equivalent test bench

The ceramic refractories composed of heterogeneous composition and structure do not possess uniform melting point. To know the refractory characteristics, the pyrometric cone equivalent (according to Seger) is to be determined which implies the temperature at which the cone's tip made of sample material softens to the point so that it touches the base plate.

The reference cone with well-established pyrometric cone equivalents at temperature intervals of 10?C and above (designated SK xx or ISO xxx) including the test cones composed of sample material are heated in the same furnace. This is done to determine accurate comparative temperature for the softening point of the refractory material to within approx. 20?C. The NETZSCH PCE 428 test bench includes a mechanical lever which enables to position the base plate for the sample and reference cones in the hood furnace below a viewing window. The viewing window in the furnace lid includes a radiation filter and surface mirror for visual determination of the pyrometric cone equivalent.