Schwabe, a subsidiary holding of Rostec Group, has for the first time shown how domestic optical glass is produced for scientific instruments, medical equipment, aerospace monitoring, and other needs.
The Lytkarino Optical Glass Plant (LZOS), which is part of the holding, was chosen for the demonstration. Throughout its history, it has refined the production of over 300 glass grades, with the company producing hundreds of tons of products annually. In particular, in 2023, it produced over 1,000 tons of glass.
In the workshops, before the glass reaches the customer, it undergoes approximately 950 technological cycles: melting in gas pot furnaces, forming, annealing, and other processes.
But first, the material itself is made from a batch, a special powdered mixture, to which cullet can be added. All of this is cooked for several days in technological containers — pots made of chamotte with a volume of 500-700 liters at high temperatures up to 1400-1550°C.
The resulting melt is clarified and homogenized, that is, made uniform, using special technological processes. After that, the glass mass is cast into a mold. For each glass grade — and there can be dozens of them — its own melting and annealing regimes are prescribed. Cooling, or annealing, takes place in a special furnace and is divided into coarse and optical (fine). The first can last two to three weeks, and the second — a month or even longer. The annealed block is removed from the furnace and undergoes inspection by the technical control department.
If the blank meets all the requirements and passes the quality control check, it is sent to the cutting areas, where the glass is cut, ground, and polished. In short, it is processed for use at the destination.
Heat-resistant thermal imaging systems are used in glass production to monitor the process. Previously, they were purchased abroad, but recently the Roselectronica holding of Rostec Group developed a new generation of such devices that operate at temperatures up to 1600-1800°C. Their mass production is scheduled to begin before the end of this year.