What is the best material for furnace cover castables?
01. Use a variety of materials
There are many materials used for furnace cover castables. It is not possible to choose the exact material. The most suitable material is selected according to the corrosion degree of different furnace temperatures.
For example, the furnace cover of calcium carbide furnace can use low-cement process cover castable, while the electric furnace cover is suitable for use with steel fiber-added furnace cover castables. Because the electric furnace cover works under conditions of high temperature erosion and rapid cooling and heating, the conditions during use of the furnace cover are quite harsh. If high alumina bricks are used for masonry, the refractory bricks will easily peel off due to the electrical holes. However, the furnace cover castable made of low-cement technology with added steel fibers has excellent thermal shock resistance and resistance to high-temperature melt erosion.
02. Adding steel fiber can improve high temperature strength
Because in the process of low cement castables, adding a certain proportion of heat-resistant steel fibers can improve the stress resistance of the castables and improve the toughness of the castable. Moreover, the steel fiber castables have good thermal shock stability, cracking resistance and Peeling. It can better extend the service life of the furnace cover.
In addition, because steel fiber is added to the castable, it can improve the strength at medium and high temperatures and reduce the residual shrinkage of the furnace cover after heating. Due to the complex smelting environment of the electric furnace cover, fire often escapes from the electrode hole area, and it is easy to peel off during the use of refractory bricks. As a result, the refurbished furnace cover cannot be used.
03.What materials are used?
The impact of the calcium carbide furnace cover is not as strong as that of the electric furnace cover. It can be made with a process ratio of low cement and micro-powder technology, because low cement can reduce the calcium content of the castable, and the later service life will be longer, and the use of micro-powder technology, What's more, the furnace cover castables produced by this process has stable performance at medium and high temperatures, and during the construction process, the amount of water added is reduced, making the castable stronger and more stable.
04. The performance is better than that of high alumina bricks
Whether it is a low-cement furnace cover castables or a furnace cover castable with refractory steel fiber technology, the performance is better than that of high-alumina bricks, because the cast furnace cover has strong integrity and does not have the problems in the refractory brick masonry process. Bricks connect the gaps. Under normal circumstances, the integral casting of the furnace cover will increase the service life by about 15% compared with the use of refractory bricks.
However, the selection of low-cement furnace cover used castables or furnace cover castable with steel fiber technology depends on the temperature of the furnace, the shape of the furnace cover, and the use environment.
