High-Quality and Hot Sale Chemically Combined Magnesia Brick in China

I believe everyone has a certain understanding of magnesium bricks. Today, Sunrise Refractory Group will introduce a new type of magnesium bricks-chemically combined magnesium bricks. Chemical bonded magnesite brick (chemical bonded magnesite brick) refers to the unsintered magnesia brick made by adding chemical bonding agent, also known as unfired magnesia brick.

 

Because the firing process is omitted, the process is simple and the cost is low. Its performance is basically similar to that of fired magnesia bricks, but because it has not been fired, no ceramic bond is formed before use, and the strength is low at 800 ~ 1300 ℃, and a weak band is formed in the bricks during use. It can cause peeling or damage of the brick, and due to the added chemical binder, it can generally form a low melt in the brick, resulting in a reduction in the high-temperature strength and slag resistance of the product.

 

Except for no firing process, the manufacturing method is similar to firing magnesia bricks. The added chemical binders include water glass, pulp waste liquid, brine, magnesium sulfate, sodium hexametaphosphate and sodium polyphosphate. When using sodium polyphosphate as a binder, there must be enough calcium oxide in the magnesia to form a product composed of sodium calcium phosphate, which is conducive to improving the high temperature strength. Chemically combined magnesia bricks can be used in the side walls of electric furnaces, lattice houses in regenerators of glass melting furnaces and cement kiln linings.

The refractoriness of magnesia bricks can reach more than 2000 ℃, and its load softening temperature varies greatly with the melting point of the cement phase and the number of liquid phases generated at high temperatures. The load softening starting temperature of general magnesium bricks is between 1520 ~ 1600 ℃, while high purity magnesium bricks can reach 1800 ℃. The load softening start temperature of magnesium bricks is not much different from the collapse temperature. The linear expansion rate of magnesium bricks at 20 ~ 1000 ℃ is generally 1.2% ~ 1.4%, and is approximately linear. When liquid phase appears in the brick at high temperature, it will shrink suddenly. The thermal conductivity of magnesium bricks is higher, second only to carbon bricks and silicon carbide bricks in refractory products, and it decreases with increasing temperature. The thermal shock resistance of magnesium bricks is poor, and the purity of magnesium bricks can appropriately improve the thermal shock resistance. Magnesia bricks have poor resistance to acidic slag. They cannot be directly contacted with silica bricks during use. Generally, neutral bricks are used to separate them. The conductivity of magnesium bricks is very low at room temperature, but it cannot be ignored at high temperatures (such as 1500 ° C). If it is used in the bottom of an electric furnace, attention should be paid.

 

Sunrise Refractory is a high-quality refractory supplier in China. If you are looking for suitable refractory bricks, you can give priority to Sunrise Refractory. You will harvest high-quality refractory bricks, competitive prices and the most professional sales team.