Magnesian high-strength gunning mix

Abstract

The invention discloses a magnesian high-strength gunning mix, which comprises the following raw materials in parts by weight: 50-97 parts of a magnesian raw material, 1-8 parts of magnesium aluminate, 1-10 parts of a plasticizer and 1-10 parts of a burning promoter, wherein the magnesium raw material is selected from sintered magnesia, high-calcium magnesia and a magnesium-chromium reclaimed material. According to the gunning mix, magnesium aluminate and a magnesian raw material quickly react to generate a gel on the premise that water exists, so that the bonding strength is generated while the adhesion performance of the gunning mix is improved; a small amount of a sintering promoter is added, so that sintering can be promoted at a high temperature, and the high-temperature sintering strength is effectively improved; and the gunning mix is limited in liquid phase quantity formed at a high temperature, small in shrinkage, good in steel slag permeability resistance and not easy to formstructural peeling.

Description

technical field [0001] The invention relates to the technical field of metallurgical refractory materials, in particular to a magnesium high-strength gunning material. Background technique [0002] In order to adapt to modern fast-paced iron and steel smelting and prolong the life of smelting vessels, it is necessary to continuously repair and maintain the weak areas of smelting vessels. Gunning is a common repair and maintenance measure, in which magnesium gunning materials are used for converter repair, RH insertion pipe repair, ladle slag line repair, etc., including magnesium gunning materials, magnesium calcium gunning materials, magnesium chromium gunning materials Materials and so on. [0003] Commonly used magnesium gunning material binders generally include one or more of phosphate series and sodium silicate. The phosphate series includes sodium tripolyphosphate, sodium hexametaphosphate, etc. The addition amount of the binder is generally 1-5 parts. A large amou...

AI Technical Summary

Problems solved by technology

A large amount of Na was introduced by the binder + Ions can greatly reduce the melting point of magnesia, forming a large amount of low-melting material at high temperature, which reduces the erosion resistance of the gunning material; at the same time, the shrinkage is severe at high temperature, forming a large number of cracks, resulting in serious penetration of steel slag, forming structural spalling

Some manufacturers prevent the formation of low-melting material by adding a small amount of carbon, but the strength of carbon-containing gunning materials is too low, and the resistance to molten steel erosion is limited

Some manufacturers use high CaO magnesia to form Na with high melting point at high temperature. 2 O·2CaO·P 2 o 5 , to improve high temperature performance, but too high CaO is prone to pulverization at room temperature, which affects the service life

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