No-contaminative Dry Vibration Refractory For Tundish Lining

Dry vibratable materials has unique merits. Because of its easy installation, fast speed of temperature rise, long life and easy separation from tundish etc. So dry vibratable materials has been developed and applied quickly in China. Compared with MgO material, MgO-CaO material have clear desulfurization and dephosphorization effect to the molten steel, and that has important significance for clean steel production.Nowadays,phenolic resin is used as the most popular binder and sintered magnesia and limestone as main starting materials. Simultaneously there is also fatal disadvantages. For instance, phenolic resin is hign in price ,moreover it can pollute environment and harm to works'health. The free CaO in magnesia-calcia is hydrated easily, which will lead to cracks or pulverization of material structure. So the dry vibratable materials be limited in practical application.The paper has do some choice experiments on inorganic binders and organic binders and has discovered some no-contamination binders which don't product the poisonus and harmful gas in the course of toasting and using. The research shows that ediblee sugar-sodium metasilicate pentahydrate as composite binder is a comparatively ideal for dry vibratable materials. The CCS of dry vibration refractory were influenced by the addition amount of binders, heating rate and category of material.Using sintered magnesia as main starting materials, edible sugare-sodium metasilicate pentahydrate as composite binder, the basic dry vibration refractory was prepared. Effect to physical properties and penetration resistance of dry vibration refractory by adding edible sugare-sodium metasilicate pentahydrate,high alumina bauxite,α-Al2O3,metal aluminum and graphite carbon have been investigated systematically. The result shows that effect of edible sugare-sodium metasilicate pentahydrate binder on MgO based dry vibration mix refractory is remarkable.; Adding high alumina bauxite,α-Al2O3, metal aluminum or graphite carbon in the materials can promote its penetration resistanc.By using sintered magnisia and calcareous materials (natural limestone, dolomite and hydrated lime) as the starting materials and the pollution-free composite binding agent as binder, the environmental friendly MgO-CaO based dry vibratable refractory was studied. The properties of dry vibration refractory were influenced by the variety, gain size and addition content of calcareous raw material were systematically investigated. The experimental results show that the MgO-CaO based dry vibratable refractory with 4%edible sugare and 2～4% sodium metasilicate pentahydrate as binder has better propeties. Natural limestone as sources of CaO, the MgO-CaO based dry vibration refractory has good comprehensive properties, while the dry vibration mix with reasonable limestone grain composition can be best.