1.Reasonable plan
a. Regarding different working conditions and different using positions for the industrial furnaces, different refractory materials. It’s the direct factor to increase the service life of refractory materials.
b. The structure of the furnace bodies should be designed reasonably. For example, the roof of the open hearth is changed from the vault to the suspended ceiling, which can remove the squeezing force between the refractory bricks to increase the service life of the refractories.
2.Construction Method
It is not only the issue of material quality that affects the use of refractory materials, but construction is also crucial.
a. The surface of the refractory bricks used should meet the conditions. They should have no lack of corners and edges, no bending, and the difference with the standards should be small;
b. Due to the principle of thermal expansion and contraction of the materials, a suitable expansion joint should be reserved to prevent the furnace body from being broken by the thermal expansion and the refractory bricks will be scrapped;
c. When the furnace lining is built with unshaped refractory materials (castables, plastics, ramming materials, etc.), it should be compacted to prevent the liquid metal and slag from penetrating and damaging the furnace lining;
3. Dryoff of the Oven
The preheating of the furnace body needs to be strictly carried out, and the baking temperature should be strictly controlled and it can not be heated too fast, which is very important.
The preheating of the furnace body is an important part to increase the age of the furnace, which is the key link to ensure the service life of the refractory. If the temperature rises too fast in the preheating stage, the water in the refractory bricks and between the joints of the bricks will evaporate and boil too violently and cause excessive expansion, which will cause the lining to expand and thereby lead to the burst and collapse of furnace. If the silicon brick is involved, it may also exist the problem that the volume of the SiO2 crystal will be changed too much and cause the furnace body to crack, so as to fall off or deform.
4. Lining Maintenance
a. Strictly control the furnace temperature to prevent strong fluctuations and over-temperature;
b. When feeding, pay attention to prevent the material from damaging the furnace lining
c. Use the gunning technique to repair the worn parts, thereby increasing the service life of the refractory lining.
