Thermal-insulation cover agent and preparation method thereof

Abstract

The invention provides a thermal-insulation cover agent. The thermal-insulation cover agent is characterized in that the thermal-insulation cover agent is composed of, by mass, 25%-45% of silicon oxide, 18%-35% of aluminum oxide, 13%-28% of calcium oxide, 2%-15% of ferric oxide, 2%-5% of carbon, 2%-5% of magnesium oxide, 1.2%-4% of expanding agents, 2.6%-5% of heat generating agents, and the balance is aluminum. The invention further provides a preparation method of the thermal-insulation cover agent. The preparation method includes the following steps of ingredient weighing, mother liquor preparation, pulping, pelleting, drying and screening. The thermal-insulation cover agent has the advantages of being good in spreadability and thermal insulation performance, and capable of reducing molten steel temperature drop speed, avoiding secondary oxidation from happening on the surface of molten steel and greatly reducing pollution to operation environment.

Description

technical field [0001] The invention relates to a covering agent used in ladles, tundishes and electric furnaces and a method for preparing the covering agent, in particular to a covering agent with good thermal insulation effect and spreading effect, which belongs to the field of liquid casting hydraulic casting. Background technique [0002] In casting production, in order to prolong the solidification time of the molten steel in the riser and ensure that the molten steel can be successfully cast into qualified ingots or billets, the molten steel must have a suitable temperature. Because the molten steel in the ladle is directly exposed to the air, it will cause steel in the casting process. The water temperature drops too fast, and the molten steel exposed in the air is easily oxidized again. In order to solve this problem, a certain amount of molten steel covering agent should be added to the surface of the molten steel after the converter is tapped. On the one hand, it c...

AI Technical Summary

Problems solved by technology

At present, many foundries mostly use carbonized rice husk as a covering agent for molten steel considering the cost. Carbonized rice husk is low in cost and easy to prepare. It is the best choice as a covering agent when the quality of castings is not high, but there are some problems as follows: (1) The problem of environmental pollution cannot be ignored; (2) The spreadability is poor. After the carbonized rice husk is added to the ladle, it often appears in a pile shape and cannot be spread out quickly, so that the surface of the molten steel is partially exposed in the air, resulting in rapid heat dissipation of the molten steel; (3) ) has poor heat insulation effect. Carbonized rice husk is carbonized rice husk as a heating agent, but due to its low calorific value and relatively short chemical reaction time, the carbonized rice husk cover layer cannot form a complete and effective heat insulation Layer, resulting in a large loss of molten steel heat

Images