Ceramic welding (build-up welding) enables to carry out restoration of lining of industrial furnaces without their stopping and cooling by organizing high-temperature fusion of refractory material on the damaged hot surface of furnace’s brickwork.
The formed welded ceramic layer is close to restored refractory brick by its chemical composition, mechanical-and-physical properties.
Technological scheme of refractory lining restoration by ceramic welding
- Nitrogen supply
- Oxygen supply
- Supply of repair material
- Lining to be repaired
“NPO MEGATEК” develops and produces ceramic materials and equipment for ceramic welding.
Duration and operating efficiency of high-temperature industrial units depends on the level of their technical operation, timely diagnosis of arising defects and qualitative performance of preventive maintenances.
Duly performance of the necessary scope of repair and implementation of the most rational preventive repairs such as ceramic welding allows considerable prolonging of service life of industrial furnaces.
Comparison of mechanical-and-physical properties of welded ceramic layer (WCL) and silica lining.
| Properties | WCL | Silica |
| Density, g/sm3 | 2,35 | 2,33–2,38 |
| Open porosity, % | 19,20 | <22,00 |
| Reversive thermal expansion at 1200°С | 1,20 | 1,20–1,30 |
| Thermal conductivity at 1000°С, W/(m•K) | 1,50 | 1,70 |
| Compression resistance in cold condition, N/mm | 20,00 | >20,00 |
| Temperature of softening, °С, not less | 1650 | >1650 |
Long-standing of repaired sites is achieved as a result of formation of strong interatomic linkage of welded layer and oven’s (furnace’s) brickwork together with the affinity of chemical and mineral composition of repair materials to characteristics of restored brickwork lining.
Now restoration of furnaces’ lining by a method of ceramic welding is a conventional process. Practically all industrial furnaces can be repaired with the help of this method. The interest shown to this method resulted in creation of materials and equipment suitable for repair of refractory lining of various physical and chemical compositions.
Ceramic welding process in pictures
Ceramic welding process in pictures
