What is pile driving material

At present, molded refractory is gradually being replaced by molded refractory mainly due to its ease of manufacture, installation and similar performance in molded products. The properties, manufacturing process and bonding mechanism of amorphous refractory material have always been the focus of research, mainly because the cast material of amorphous refractory material is the most common and widespread. The hydraulic binder commonly used in refractory castings is mainly calcium aluminate cement. The CaO contained in this binder generates calcium feldspar, calcium aluminum yellow feldspar and other substances under the action of high temperature to reduce fire resistance and improve thermal shock resistance.

1. Investigation of the properties of amorphous silica sol in combination with refractory material

As a binder, silica sol is mainly used in ordinary pourable, self-flowing pourable and ramming materials.

1.1 Performance study of silica sol combined with normal pouring

Research on the properties of silica sol combined with ordinary casting mainly includes rheological properties, construction properties, thermal shock resistance, burst strength and so on.

1.1.1 Rheology, construction and blow-out strength

Relevant studies have shown that an appropriate amount of low temperature oxidized triglyceride, active ultrafine SiO2 powder and active AI2O3 micropowder can effectively improve the rheological properties of silicon soluble sludge. A suitable amount of citric acid can reduce the viscosity of the silica sol slurry, but also improve the liquidity of the cast material in a short time to promote the condensation-hardening matrix and improve the strength of the room temperature.

1.1.2 Physical properties at room temperature and high temperature

Many studies believe that the nanometer SiO2 in silica sol dehydrates quickly under the hydrated acid environment at 50 ° C. In addition, the water in the larger capillary pores was lost at 240 ° C. At around 1000 ° C, the capillary moisture is completely lost, so that the loss of mass is increased and the lack of moisture, silica gel, turns into invisible SiO 2.

1.2 Performance of silica sol combined with self-flowing cast material

Self-flowing pourable material is a type of pourable refractory material that can flow and degas without vibration. It consists of a refractory aggregate, powder, highly efficient dispersant, admixture and binder with particle size grading. This type of self-flowing casting material is mainly suitable for thin-walled and complex molded parts.

1.3 Properties of silica sol combined with ramming materials

The ramming materials combined with silica sol consist mainly of refractory aggregate, powder, binding agent, added water and other liquids. This material is mainly used for furnace cooling equipment and for filling masonry clearances. There is iron hook piling material in the piling material, that type of raw material that is commonly used as a binder. This type of pile material is better in early-life strength, easy to construct, and widely used. Under the action of high temperatures, this type of ramming material has many pores due to the oxidation of the carbon binder, resulting in a decrease in density and strength and poor performance. However, using silica sol in combination with ramming materials can improve performance, reduce costs, and improve the artificial operating environment.

1.4 Properties of silica sol combined with injection material and injection material

Jet material is a type of loose refractory material. Depending on the condition and process of the blasting material, it can be divided into wet blasting material, semi-dry blasting material and flame blasting material. Silica sol can also be combined with compaction, which consists mainly of refractory aggregate and powder of a certain size. Under the action of this raw material, the binder and extruder, which are made of additives, create pressure to achieve an overstock construction. In addition, the extrusion construction of the pasty refractory materials is generally divided into cold solid pressing and thermosetting pressing. Pressing it into the structure can help accomplish the furnace repair.

2. Applied research

2.1 Use of common castings in combination with silica sol

Ordinary casting material has a very wide range of uses. Silicon sol is mainly used in the middle of the BaoYongJiu line of steel making system, the triangle electric furnace top, mainly used in the casting industry, induction coreless furnace, furnace bottom and pouring barrels. The aluminum industry is commonly used in the aluminum melting furnace of the molten pool, the furnace door and the side walls, the calcination zone and the high temperature rotary kiln incinerator, etc. A Metallurgical Building Research Co., LTD. Has successfully applied silica sol and corundum a Mo combined stone to the air inlet and furnace roof and the side wall of steel mills. Ultimately, the drying and baking process is effectively simplified, the lining time is reduced and the equipment utilization rate is achieved. In addition, during the urgent repair, silica sol was applied to the main fork of the hot blast furnace in combination with quick-drying cast material and a good maintenance effect was achieved. In a certain application, a good repair in the hot state is achieved by combining silica sol with corundum and silicon carbide in a castable manner.

2.2 Use of silica gel combined with self-flowing cast material

Compared to conventional carbon ramming materials, the self-flowing casting material combined with silica sol has good thermal conductivity and has a good advantage in terms of cooling effect and construction convenience. The new silica sol in combination with the artesian iron groove Al2O3-SIC-C can be partially repaired, and the iron flow can reach 200000T after practical use. In addition, the slag resistance of the new silica gel in combination with the castable Al2O3-SIC-C is better than that of the low-cast cast. After practical application, the iron flow can be estimated at 163,000 T. In practice, we have found that the iron flux from silica sol combined with a dry-cast iron trench made from refractory raw materials can reach more than 150,000T.

2.3 Use of silica sol in combination with compression feed

A combination of silica sol and pressing into the material was used for the maintenance of the blast furnace floor in Shagang, the repair of the hot air surrounding pipe in the steel pipe factory and the production and maintenance in the Wisco sintering plant. which can realize the minimal pollution from production, construction and application.

3, conclusion

Silica sol combined with refractory material has good properties such as medium and high temperature resistance, which can save time and effectively realize environmental protection. In practical use, however, the amorphous product in combination with silica sol and the product in combination with high-alumina cement are relatively expensive, so that their use is limited. Further work by refractory researchers is to improve the demolding resistance of this material and to expand its application in all areas of life.

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