The flexible using in the laboratories, for the testing of the different materials by the heat processing, whereat from the charge is not passing any incursive matters, which can attack the coils or the brick lining.

Furnaces are used in laboratories for heat-treatment testing of various samples, when the agresive fouling, which would pelt with the spirals, can be formed.

Vertical charging (samples for testing) into ceramic muffle. This muffle prevents from acces of possible agresive fouling, forming at heat treatment, to heating elements

Furnaces are suitable for testing technology where the exact distribution of temperature, the controlled increase and decrease of temperature, and controlled cooling are important, and where it is also desirable that the heating elements are not in the interior space with the samples.