... of asbestos sheets, then five layers of refractory bricks, then with refractory filler, which form into ... arch. After drying up, vertical shaped magnesium bricks 380 are laid on top;1.3.2 ... more temperature holding effect of the entire furnace, clay bricks in 113mm thickness are laid between the wall ... on the top of the furnace, chromium-magnesium bricks, which have better thermal stability, are used ...