Application of MgO-C bricks in ladle

Currently, inhibition of steel temperature droping has become a major issue for many steel plants. Therefore, in order to suppress temperature drop of molten steel, there has a test to study insulation problem of refractory lining in 185t ladle, by comparing three different measures.

First: Reducing the heat transfer effect of sidewall castables (30% reduction). This method is by reducing coarse particles in refractory castable, increasing porosity and other measures to reduce the thermal conductivity, to suppress heat dissipation.

Second: Using insulation materials in the backlayer of wall castable. This method is to use one layer insulating bricks with less than 1W (m℃) thermal conductivity between ladle steel shell and wall castable, to inhibit heat dissipationheat.

Thrid: Reducing the heat transfer of slag line MgO-C brick heat transfer (30% reduction). This method is developed in recent years, to select lower thermal conductivity of MgO-C brick from the high thermal conductivity of magnesia carbon brick for slag line, to suppress heat dissipation.

After comparing, the results found that: only in reducing the thermal conductivity of slag line magnesia carbon bricks , the effect of suppressing steel temperature dropping is significant, up to 2℃. The durability is same or higher than ordinary ladle, less cracks, the residual condition after use is also very good.

Changxing refractory provides refractory products, calcium silicate products, castable & mortar, china refractory brick, ceramic fiber felt, ladle & tundish nozzle, ceramic fiber with high quality for you. Such as high alumina refractory bricks, magnesia carbon brick, clay refractory bricks and other refractory products.

Article Source：Application of MgO-C bricks in ladle
Company name:Henan Xinmi Changxing Refractory Materials Co.,Ltd
Email: sales1@chinafirebrick.com
Website:http://www.chinafirebrick.com/

Influence of Refractory Materials for Ladle Leaking

Slide gate refractory part is a central part of the slide gate, is a key component in direct contact with the control of molten steel, its physical and chemical properties is a key factor in determining whether the normal use of the sliding gate.
1.Ladle well block is of low hot crushing strength. When using air pick to chance upper nozzle well block, the well block would be easy to breakdown. The inner diameter would get larger, and gap between well block and upper nozzle may get bigger. The molten steel would easy to get into the gaps, and leak would easy to happen.
2.Ladle well block is of weak thermal resistance. During working period, like casting and hot repair, the temperature difference would be very big, and the well block would easy to break down. If can not be found in time, molten steel would leak through the gap between upper nozzles well block and nozzle.
3.Ladle sliding gate plate is of weak erosion resistance. When doing half hole casting, the lower plate would bear higher erosion strength, and easy to appear groove. After closed the plate, molten steel would leave in the groove and get cold there, in which way the two plates can not work smoothly.
4.If the low sliding gate plate break down, gap would easy to appear when casting, and molten steel would leave through it. If terrible, the sliding gate plate would easy to break into pieces because of molten steel pressure.

5.Sliding gate plate mortar can not bear erosion well, in which way gaps would appear and cause leak. If can not be found in time, this would cause leak between upper nozzle well block and well block, upper nozzle and upper sliding gate plate.
Changxing refractory provides refractory products, calcium silicate products, castable & mortar, china refractory brick, ceramic fiber felt, ladle & tundish nozzle, ceramic fiber with high quality for you. Such as high alumina refractory bricks, magnesia carbon brick, clay refractory bricks and other refractory products.
Article Source：Influence of refractory materials for ladle leaking
Company name:Henan Xinmi Changxing Refractory Materials Co.,Ltd
Email: sales1@chinafirebrick.com
Website:http://www.chinafirebrick.com/

Sliding gate damage theory and meaning of conjunction

Ladle slide gate plate mainly contains two types, alumina carbon and alumina zirconium carbon. With steel production increasing and steel quality improving, calcium treatment process is applied, therefore, calcium content in the melton steel increased. Using alumina carbon and alumina zirconium carbon slide gate plate when casting steel, SiO2 and Al2O3 in the slide gate plate would mixed with Ca, CaO in the melton steel or slag and get into low-melting point materials and feldspar, which would cause damage of slide gate plates. This type low-melting point materials would be easy to crushed down by erosion, new low-melting point material would re-appear. This progress would cause the erosion heavier, in which way the ladle slide gate plate would be damaged gradually.

Conjunction of slide gate plate can reduce the number of turnover ladle,?low down?ladle serves and turnover pressure.?In addition, ladle slide gate plate conjunction can low down labor working, improve ladle lining temperature, thus low down casting temperature and bring a number of benefit for production and reducing cost.

From Year 2008, our factory succeed to develop double conjunction and from Year 2010, triple conjunction is developed. With the triple slide got into the normal production, on-site production, reduce labor intensity, the effect of reducing the cost of generation is very obvious.

Changxing refractory provides refractory products, calcium silicate products, castable & mortar, china refractory brick, ceramic fiber felt, ladle & tundish nozzle, ceramic fiber with high quality for you. Such as high alumina refractory bricks, magnesia carbon brick, clay refractory bricks and other refractory products.

Article Source：Sliding gate damage theory and meaning of conjunction
Company name:Henan Xinmi Changxing Refractory Materials Co.,Ltd
Email: sales1@chinafirebrick.com
Website:http://www.chinafirebrick.com/

Key technology of smelting stainless steel in combined blowing converter

Hot metal dephosphorization technology. When the hot-smelting converter uses molten iron to smelt stainless steel, the dephosphorization of the molten iron is first carried out, or the dephosphorization is carried out by a mixed iron car, or the dephosphorization is carried out in a double-blown converter.
Converter thermal compensation technology. Since stainless steel is a high-alloy steel, it is necessary to add a large amount of cold alloy during smelting. For example, only the sensible heat and oxidation heat of molten iron are used to make steel in the converter, and the heat energy is obviously insufficient. According to the calculation, the heat shortage of the stainless steel SCTS304, SC1S316, SC1S410, SC1S420 and SUS430 in the whole molten iron condition is about 11.5%, 14.6%, 6.1%, 8.0% and 5.4%, respectively, for which the development cost is low. Technology is an indispensable technology for smelting stainless steel in a combined blown converter. Nowadays, the thermal compensation technology of the secondary combustion (called PC gun) of the top of the furnace and the broken coke block (granule) and the double-flow oxygen lance are generally used.

Thermal compensation technology for crushing coke blocks (grain) on the top of the furnace: The thermal compensation technology using broken coke particles as a heat source has the following advantages over the method using FeSi as a heat source:

a. The remaining coke blocks (granules) remaining in the steel plant can be used, and the source is wide and the price is cheap;
b. Even if used in large quantities, the amount of slag increases a lot;
c. The generated CO gas can be effectively utilized as a heat source.
Thermal compensation through secondary combustion: The secondary combustion thermal compensation technology of the dual-flow oxygen lance can tap the potential of chemical heat in the furnace, thereby reducing the amount of coke thermal compensation, thereby shortening the blowing time and oxygen consumption.

The use of a dual-flow oxygen lance increases the secondary combustion rate of CO.
The secondary combustion rate is increased by controlling the ratio of the oxygen amount of the main and auxiliary oxygen holes. The secondary combustion rate is the highest when the ratio of the secondary pore oxygen to the main pore oxygen is 20%. In addition, increasing the height of the lance is also beneficial to increase the secondary combustion rate.

Since the main alloy of stainless steel, the inscription element, is easily oxidized at high temperatures, it is necessary to have sufficient decarburization capability in the converter to smelt stainless steel, and also to suppress the oxidation loss of chromium.

According to the principle of metallurgy, the higher the temperature of molten steel, the better the decarburization reaction; the lower the partial pressure of CO in the converter is beneficial to the reduction of chromium, and the oxidation loss of chromium can be suppressed while blowing oxygen decarburization. In order to meet the requirements of thermodynamic theory, the converter is usually diluted or refined to dilute the concentration of CO generated in the converter due to the decarburization reaction with a large flow of bottom-blown inert gas to reduce the partial pressure of CO. At the same time, it can also promote the stirring of molten steel and accelerate the decarburization reaction. In addition, in the control of molten steel temperature, we must first overcome the problem of insufficient heat source, and then effectively achieve high temperature (≥1700 °C) operation.
Changxing refractory provides refractory products, calcium silicate products, castable & mortar, china refractory brick, ceramic fiber felt, ladle & tundish nozzle, ceramic fiber with high quality for you. Such as high alumina refractory bricks, magnesia carbon brick, clay refractory bricks and other refractory products.

Article Source:Key technology of smelting stainless steel in combined blowing converter
Company name:Henan Xinmi Changxing Refractory Materials Co.,Ltd
Email: sales1@chinafirebrick.com
Website:http://www.chinafirebrick.com/

Development of ladle lining refractory materials

20th Century 50--70 years, China's steel plants mainly used aluminosilicate refractory materials, including clay, high alumina brick and so on. Since the 1980s, China has successively developed the aluminum-magnesium carbon, coal quality calcium and magnesium and other several series of new steel package refractories. Wherein the aluminum-magnesium carbon refractory materials are of varieties, all specifications, is China's major ladle refractories.

In earliest 20th Century 50--60 years, a variety of clay bricks were mainly used in our country. Due to low cost, until the 1980s, some steel plants were using clay bricks as ladle lining material. Although clay bricks is no longer used as ladle material so far, it had made a great countribution for recovery and future development of China's steel industry in the early days.

With the continuous development of steelmaking technology, steel quatity and quantity, clay bricks was no longer used because of short service life. Some of our mills started using a variety of high alumina bricks as ladle lining material, in which way the ladle life got a greatly improvement.

With the continuous improvement of steelmaking technology, high aluminum ramming mass, wax brick, alumina magnesia, aluminum-magnesium casting material, aluminum-magnesium unfired brick, aluminum-magnesium spinel castable, aluminum MgO-C, magnesium aluminate spinel brick, aluminum-magnesium unfired brick and a series of high-grade refractory materials appeared to adapt to higher demand.

Changxing refractory provides refractory products, calcium silicate products, castable & mortar, china refractory brick, ceramic fiber felt, ladle & tundish nozzle, ceramic fiber with high quality for you. Such as high alumina refractory bricks, magnesia carbon brick, clay refractory bricks and other refractory products.

Article Source:Development of ladle lining refractory materials
Company name:?Henan Xinmi Changxing Refractory Materials Co.,Ltd
Email: sales1@chinafirebrick.com
Website:http://www.chinafirebrick.com/