Hello, welcome to the official website of Liaoning Hongyu Refractories Group Co., Ltd.
Liaoning Hongyu refractory Group Co., Ltd.
Address: two room village, Guan Tun Town, Dashiqiao, Liaoning, China
Web site: www.hy-ref.com
Contact: high general
Zip code: 115100
The refractory materials used for converter tapping hole are easily affected by many factors, and the main damages of magnesia carbon bricks are as follows:
1. Oxidation of furnace gas
During the process of converting the converter into the molten iron and blowing process, the tapping mouth is in the high temperature erbium atmosphere. The furnace gas produced during the blowing process contains a large number of CO, and the C-O reaction occurs when the tapping mouth is discharged. The decarburization layer is generated on the surface of the inner wall of the tapping mouth, which directly causes the damage of the tapping mouth.
2. Friction damage and mechanical erosion of molten steel and slag.
At the time of tapping, the tapping port should bear the huge pressure of the molten steel in the converter. At the same time, when the steel and slag outflow out of the tapping port, the inner wall of the tapping mouth is rubbed and scoured, which directly causes mechanical damage to the inner wall of the tapping mouth.
3, high temperature melting of molten steel and slag
The tapping temperature is generally 1680~1710 C. Under the action of high temperature steel, the material of the tapping mouth will be softened, the strength is reduced and even melted, resulting in the damage of the tapping port.
4, chemical erosion of molten steel and slag, the physical and chemical indexes of tapping hole are shown in Table 1.
When converter smelting reaches the end tapping, the molten steel generally has strong oxidation, especially the oxidizing property of the slag is higher. Under the condition of high temperature and high oxidation, the following chemical reaction will occur.
C+O - CO (1)
MgO+ C - Mg +CO (2)
During chemical reaction, W (O) in molten steel or slag will seize carbon from magnesia tapping material, resulting in loose structure and poor strength of refractory materials. In addition, slag basicity is too low or MgO content in slag is less, which will produce the following chemical reactions:
SiO2+C, SiO + CO (3)
It will also aggravate the chemical erosion of the tapping mouth.