Name: Liaoning Ming Yan new material manufacturing Co., Ltd.
Contact: Manager Mu
Mobile phone: 13940737885
Address: Guan Tun Village, Guan Tun Town, Dashiqiao City, Yingkou, Liaoning
PN series magnesia alumina-magnesia-carbon brick adopts super bauxite or corundum as aggregate, and strengthens the matrix with phenolic resin as binder, and adopts mechanical compression molding. It has the characteristics of corrosion resistance, peeling resistance and high strength, and is suitable for the bottom and wall of ladle.
PN series magnesia-alumina-carbon bricks are based on alumina-magnesia-carbon bricks to adjust the process and technology to enhance the corrosion resistance and spalling resistance of materials, suitable for the bottom of ladle and ladle wall and other parts, can significantly improve the service life of ladle. Carbon has been widely used in refractories in metallurgical industry. In the past, many new products were developed to adapt to the development of new metallurgical processes and refractory technology. Refractory experts have long known about the excellent properties of magnesia-alumina-carbon bricks with different forms of carbon in refractories. In refractory oxides, carbon can reduce the wettability of slag, molten steel and refractory, increase its thermal conductivity and reduce its expansion, so that refractories have excellent thermal shock resistance. In addition, carbon has high thermal stability and its sublimation temperature is about 4000 C. At the pressure of 110-140 bar, the three-phase point (solid/liquid/gas) of carbon in the phase diagram is close to 4020 C, so the carbon sublimates and does not melt at the pressure below 110 bar. Because carbon is oxidized at high temperatures, the above results can only be applied under certain conditions.
At present, the most important applications of carbon containing refractories are:
1. converter, electric furnace and ladle lining
2. crucible for melting metal
3. key components for continuous casting
4. refractories for blast furnace ironmaking
5. by adding carbon, a variety of refractory bricks, especially magnesia carbon high-grade basic refractories, can be produced.
There are many ways to add carbon to refractory materials:
1. tar pitch or synthetic resin impregnated magnesia alumina carbon brick
Sintered oxide refractories
The porosity of the openings is about 12%, and most of these pores can be filled with tar pitch or resin. Due to volatilization and relatively low density of volatiles, the residual carbon rate of these products is about 2%~3%. Using bauxite clinker, fused magnesia, phenolic resin and high-purity graphite as main raw materials, alumina-magnesia-carbon brick with various additives, good results have been achieved in the application of 80 ton converter ladle in Xuanhua Iron and Steel Works. 1. Wet spraying repairing is to mix refractory aggregate, binder, additive and water into a certain consistency. A method of spraying mud into the surface of a spraying machine with compressed air magnesia-alumina-carbon bricks. Its characteristics are simple operation, high adhesion rate and quick sintering. But because of the large water content and fine grain, the shrinkage is also large. At the same time, because the spray coating is thinner, the durability is not good.
2. Semi-dry spraying is a method of mixing refractory aggregate, binder and additive with water through the water ring hole at the spray gun end and spraying compressed air to the spray patch surface. The amount of water can be adjusted at any time according to the spray patch situation, generally fluctuating between 10 and 20%, which is lower than that of wet spraying patch. It's much more. Therefore, the spraying layer with high volume density and small shrinkage can obtain a thicker spraying layer with better durability, but the springback is slightly higher than that of wet method.
3. Flame spraying is a repairing method by which refractory aggregate, flux or heating agent are transported to the nozzle by compressed oxygen, and burned with high calorific value fuel. The surface of refractory aggregate particles of magnesia-alumina-carbon brick is instantly heated to a melting or semi-melting state, and then sprayed and adhered to the furnace lining. The structure is dense, high strength, corrosion resistance, strong scouring resistance, solid and durable. But the flame gunning device has high cost, complex technology and high energy consumption.