Thermal self-flow material and spray material for converter lining repairing
Due to the different working conditions of various parts of converter lining material, the different parts of the converter lining are unevenly damaged. The repair of the converter lining is a powerful measure to extend the life of lining, balance the damage of lining and reduce the production cost. The two commonly used for converter lining repairing materials are thermal self-flow repair material and spray material.
Thermal self-flow repair material for converter
Thermal self-flow repair material uses magnesia and magnesium dolomite sand as the basic raw materials, the process performance mainly depends on the bonding agent, commonly used binders are asphalt, resins, or the mixture of the two. It is mainly used for repair of the steel surface and the tapping side of the converter. It is also called the large surface repairing material. When used, the repairing material is put into the furnace, by shaking the furnace body, and under the action of residual heat in the furnace, the repairing material flowing and spreading on the eroded portion of the lining.
Thermal self-flow repair material should be with the following features:
1, Good spreading and fluidity at the residual heat of the converter lining.
2, Can solidify quickly after spreading.
3, Good adhesion to the original lining material.
4, Good corrosion resistance and prevent the repairing layer from being eroded during the next smelting.
Spray material for converter
Partial damage places and the parts that is not suitable to repair of converter such as the trunnion and the slag line can adopt the spray material. The refractory material is sprayed on the part with severe local damage, so that it is sintered with the furnace lining brick to repair the lining. The main raw material for converter spray material is composed of magnesia, binder, plasticizer and a small amount of water.
Spray material for converter should be with the following features:
1, Has sufficient refractoriness to withstand the high temp in the furnace.
2, The spray material can be attached to the lining and with less detach.
3, The spray material adhesion layer can be well sintered with the surface of the furnace, melted into one body with high strength.
4, The spray material adhesion layer can withstand high temp slag, molten steel, furnace gas and metal oxide vapor erosion.
5, The spray material can flow smoothly in the spray pipe.
Therefore, it is much more reasonable to select suitable repair materials according to different furnace conditions and different parts.