Magnesia-calcia dry type working liner for tundish and preparation thereof

Abstract

The invention relates to a magesia-calcia tundish dry working lining refractory and a method for preparing the same. The technical scheme comprises mixing 55-65wt% of particle material with a grain size of 3-0mm, 22-35wt% of powder with a grain size less than 0.088mm, 0 or 0.5-8wt% of additives and 6-12wt% of binding agent according to a theoretical content of MgO 55-85wt% and CaO 10-40wt%, baking at 200-350 DEG C after stirring and vibration molding, getting the tundish dry working lining after demoulding, wherein the particle material is one or a mixture more than one selected from the magnesia, magnesite, limestone and dolomite; the powder is one or a mixture more than one selected from the magnesia, hydrated lime, limestone, dolomite and magnestie. The invention has advantages of simple technology, convenient construction, low cost, environment friendly and saving energy, and the magesia-calcia tundish dry working lining has a good metallurgical effect and the feature of easy disintegration after use.

Description

technical field [0001] The invention belongs to the technical field of unshaped refractory materials. In particular, it relates to a magnesium-calcium tundish dry-type working lining refractory material and a preparation method thereof. Background technique [0002] The tundish is the last metallurgical container in the steelmaking process, and it has a great influence on the quality of molten steel. Therefore, people have done a lot of research work on this: such as reducing the consumption of refractory materials in the tundish, and giving full play to the metallurgical functions of refractory materials (Li Nan. Reaction between refractory materials and steel and its influence on steel quality [M]. Beijing: Metallurgical Industry Publishing House, 2005.158-215.; Wu Huajie, Cheng Zhiqiang, Jin Shantong, etc. Effects of magnesia-calcium and magnesia tundish coatings on the cleanliness of molten steel [J]. Refractories, 2002, 36(3): 145- 147.); reduce construction labor and...

AI Technical Summary

Problems solved by technology

[0004] The above-mentioned dry material is a non-aqueous material. Although it has the characteristics of convenient construction, low energy consumption, long life, and improved working efficiency of the tundish, it has the following disadvantages: phenolic resin is not only expensive and costly, but also in the baking process There are irritating gases such as ammonia, formaldehyde, and free phenol, which pollute the environment and endanger the health of workers. The carbon and hydrogen after carbonization have obvious carbon and hydrogen increases; During the baking and use process, the formula material also produces strong irritating gas, which pollutes the environment and endangers the health of workers; with single sodium metasilicate as the binder, it needs to be added in large quantities to ensure the low-temperature strength of the dry formula material, resulting in an increase in low-melting materials , but significantly affect the high-temperature service performance and disintegration performance of the material; using magnesia and forsterite as the main raw materials has little effect on reducing the inclusions in molten steel and improving the quality of the billet; introducing CaO-containing materials such as magnesia-calcium sand and quicklime, due to CaO waterproofing technology is not yet perfect, but it is very easy to hydrate, resulting in expansion and pulverization of magnesia-calcium sand or quicklime, resulting in cracks or cracks in the material