In the process of using the lining of the converter, the structure of the lining is easily damaged due to the fact that the refractory materials at the charging side, the steel outlet side and the bottom of the furnace are under high temperature for a long time, and are subjected to the impact of mechanical force, the repeated erosion of slag and molten steel, and the loss caused by the rapid temperature change, which leads to the decrease of the furnace life. At the same time, in order to reduce the cost of steelmaking steel mills have greatly increased the use of converter waste steel increased the front large face lining refractory mechanical damage; At the same time, the peroxidation phenomenon in the furnace is serious, which accelerates the erosion of lining brick and sharply reduces the life of the converter.
Because the damage of converter is more than that of normal condition, the repair system of converter should be adjusted. First of all, the number of bof repair should be increased, but the increase of the number of bof repair will correspondingly reduce the working time of bof steelmaking, which is bound to reduce the steel output, which is unacceptable to all steel mills. In order to solve the contradiction between the repair of converter lining and steel output, jiaozuo jinxinhengtuo new materials co., ltd. developed a new repair method of converter lining: rapid furnace repair method or compound furnace repair method.
1. Converter maintenance materials
Ø solid repairing
Spray coating Ø converter
Ø longevity and new environmental protection their burden
2. Introduction of resin-bonded solid charging performance
Resin combined with solid charging replaced the traditional asphalt combined with large fabrics, to avoid the sintering process of "yellow smoke", pollution of the environment phenomenon. Electric fused magnesia as the main raw material, phenolic resin as the binder, adding burning agent, with high thermal strength, strong mechanical erosion resistance, chemical erosion resistance and other characteristics, this charging has simple construction operation, filling furnace quickly, but there is the problem of sintering time is too long, relatively low life. Suitable for converter steelmaking at a low tempo.
3. Performance of converter spray coating
Suitable for lug shaft spray maintenance, converter spray coating strong adhesion, high adhesion rate; High bonding strength, anti-peeling; Rapid hardening and high strength; High temperature resistance, corrosion resistance and other characteristics.
4. Introduction of new environment-friendly and long-life self-current charging performance
Jiaozuo Jin Xinheng billiton new material co., LTD., research and development of new environmental longevity their repairing belongs to the environmentally friendly materials, with high purity magnesia, fused magnesia aggregates and fused magnesia powder as the main raw material, choosing the appropriate particle size distribution, using environmental protection liquid binder, material of low water addition, good liquidity, add the plastic material can achieve rapid sintering, repair the lining structure compact. With short sintering time, no toxic smoke emissions, good resistance to slag, steel penetration and erosion performance, no pollution of the construction environment, service life greatly improved; It is an ideal material for prolonging the service life and maintaining the long life of the converter.
4.1 physical and chemical indexes of new environment-friendly and long-life self-current charging performance
4.2 performance characteristics of new environment-friendly and long-life self-current charging
Ø environmental protection free from contamination, sintering process does not produce smoke and toxic gases, polluting the environment construction
Ø main raw magnesite is given priority to, not to the furnace into the S/C and other impurities
Ø their sex good, their spreading in the furnace, without rocking furnace repeatedly, good liquidity can repair to the converter lining tiny uneven surface, fill the converter bedding face of potholes, improving the furnace shape
Ø USES fast sintering technology, sintering time is short, generally no more than 30 min, save the fettling time, improve the operation efficiency of converter
Ø sintering, prevent spillage of sandwich layer lead to hidden trouble
Ø low porosity, repairing lining structure density, good erosion resistance, increase service life
Ø ceramic combination, oxidizing atmosphere bonding properties are not affected
4.3 performance comparison of converter maintenance materials of different combined systems
4.4 field use of new environment-friendly and long-life self-current charging