Common Type of Slide Gate Refractory
High-aluminum Slide Gate: mainly made of high-aluminum raw materials, with high refractoriness, mechanical strength and corrosion resistance. Its high alumina content can withstand high temperatures and erosion of molten steel, and is suitable for some occasions with high requirements for refractory performance, but the thermal shock stability is relatively poor.
Aluminum-carbon Slide Gate: including unfired aluminum-carbon and fired aluminum-carbon slide. In order to improve the corrosion resistance and thermal shock stability of unfired aluminum-carbon slide, synthetic mullite, andalusite and silicon carbide materials are added to the granular material, and corundum and silicon carbide are added to the matrix, but there are problems such as low hot strength, severe wear of the sliding surface and poor cracking resistance. Fired aluminum-carbon bricks have low thermal shock resistance and cannot be used continuously for many times. In addition, carbon is easily oxidized during use, and the corrosion resistance is reduced.
Aluminum-zirconium carbon Slide Gate: developed on the basis of fired aluminum carbon skateboard, using low expansion rate Al2O3−SiO2−ZrO2 raw materials to make refractory materials with baddeleyite, mullite, corundum, etc. as the main crystal phase and carbon bonding as the characteristic. It has quite good performance and applicability, but cracking and sliding surface wear during repeated use are the key to restricting its life improvement, and its resistance to calcium erosion is poor when casting calcium-treated steel.
Magnesium carbon Slide Gate: first used in Europe, magnesium oxide has good mechanical stress resistance and chemical erosion resistance, which can meet the requirements of casting calcium-treated steel and high-oxygen steel to a certain extent. However, the thermal expansion coefficient of magnesium oxide skateboard is large, and thermal spalling is prone to occur when casting steel, and the thermal shock resistance needs to be improved.
Spinel carbon Slide Gate: magnesium aluminum spinel is used as the main crystal phase, and it is characterized by a composite combination of ceramic and carbon. The thermal expansion coefficient and elastic modulus of magnesium aluminum spinel material are smaller than those of magnesium oxide, and its thermal shock resistance is stronger than that of magnesium oxide. However, spinel materials react slowly with calcium in steel to produce low-melting products that affect their service life.
Zirconia Slide Gate: Zirconia skateboards formed by hot pressing have the characteristics of high high temperature strength, low apparent porosity, and small pore diameter. They have good resistance to molten steel corrosion when used on tundishes. However, due to cost and other reasons, the industry generally uses zirconia rings embedded around the casting holes of aluminum-carbon skateboards to make composite skateboards.
KERUI Πυρίμαχο υλικό supplies different types of Slide Gate, nozzles and Well Block. If you have any needs or questions, please contact us.