How to remedy the cracks in the use of high aluminum castables?

December 07, 2018

How to remedy the cracks in the use of high aluminum castables?

Nowadays, kiln masonry technology has been gradually replaced by refractory castables from refractory bricks. Among various of refractory castables, high alumina castables have the advantages of wide application range, favorable price and good performance, so they are favored by many downstream manufacturers. However, no matter what kinds of refractory castables are used, if they are not carried out according to professional technical requirements during the construction and baking process, it is easy to cause problems such as cracking,falling off in castables during the use of refractory castable.

When the high aluminum castable is used, if the temperature exceeds the limit of the castable, the castable will crack or fall off. In the face of this phenomenon, how should we solve it?

When inspecting high alumina castables, if it is found that there is cracking in the castables, firstly check whether the cracking is serious. If it is only a slight crack and the cracking width is not more than 5mm, it is not a mesh inertial cracking, it can not be repaired in general. This phenomenon is basically normal and will not affect the use.

If the casting crack of the castable is longer and wider, some refractory fibers may be filled in the middle of the crack. The function of adding the refractory fiber is mainly to prevent the heat from being transmitted into the crack and causing the crack to become wider and larger. If the cracks of the castable lining are relatively large or even slightly detached, it is necessary to clean the surrounding or falling part of the castable cracks. When the local area is not more than 10cm×10cm, the small hole with a depth of not more than 5cm should be dug,and the hole wall shall be cleaned up and filled with castable or plastic.

If the cracking of the castable lining is serious, when it exceeds 10cm×10cm, the lining layer should be dug to the furnace wall and filled with castables of the same material. There are at least two anchors in the filling range.

If none of the above methods meet your needs, or the castable cracks are very large, throughout the furnace, you should check carefully whether there is a problem of quality or not. It is recommended to replace the new castables in time for furnace to stop the repair.

When the castable is used, it has a service life, and when the furnace is running, it must also abide by the operating rules. When operating normally, it is also necessary to carefully check whether the furnace is running in a bad way or not. It should not be lazy to avoid checking, which will cause the kiln to run in a bad way.