International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The research is related to the creation of new compounding formulations for the production of “yellow” paving stones. This was necessary due to denied access to a potential source of suitable raw material from the deposit near the village of Svetlen, Popovo municipality. Marlstone raw material from this deposit has the necessary qualities for such production, as a result of which, after hightemperature liquid-phase synthesis, new petrurgic phases with high physicochemical and mechanical properties can be formed. The new compounding formulation of the molding mass was developed on the basis of marlstone sedimentary rock from the Alexandra deposit, located near the village of Lovets, Targovishte district. The use of this compounding formulation makes it possible to obtain appropriate physicochemical and mechanical properties and a yellow coloring equivalent to that of the reference samples.

Due to the specifics of marl clays, research to date has shown the need to stabilize these clays with respect to their critical melting point. The research is based on a previous analysis of pure raw material from marl clay, located in the area of the village of Lovets, which is modified by various additives. On the one hand, the modification is used to stabilize the ceramic mass and on the other hand, by adding various agents, the aim is to lighten the composition and obtain the required color pattern. For the purposes of production, the experimental part includes laboratory development of a scale model of yellow paving stone. The development presents the entire process of creating instrumental equipment – model making and matrix construction, and molding of finished products – pressing process for paving stones productionfrom modified marl clay. The technological cycle that can be implemented in the real conditions for yellow paving stones production will rely on the present study.