Industry Knowledge of Mullite Refractory Castables

Mullite refractory castables are widely used in various industries such as metallurgy, petroleum, chemical, and power generation due to their excellent high-temperature performance, good thermal shock resistance, and strong erosion resistance. In this article, we will discuss the industry knowledge of mullite refractory castables, including their classification, technical parameters, and production process.

Mullite refractory castables are classified into different grades based on the mullite content and the amount of binder used. Generally, they are divided into three levels: low, medium, and high grades. Low-grade mullite refractory castables have a mullite content of less than 60%, medium-grade mullite refractory castables have a mullite content between 60% to 80%, and high-grade mullite refractory castables have a mullite content exceeding 80%.

The technical parameters of mullite refractory castables include bulk density, apparent porosity, compressive strength, thermal conductivity, and refractoriness. The bulk density of mullite refractory castables ranges from 2.2 to 2.8 g/cm³, and the apparent porosity ranges from 3% to 10%. The compressive strength of mullite refractory castables is generally around 100MPa. The thermal conductivity of mullite refractory castables is low, typically between 0.5 to 1.0 W/mK. The refractoriness of mullite refractory castables can reach up to 1790°C.

The production process of mullite refractory castables comprises three steps: raw material preparation, mixing, and placement. The raw materials used for mullite refractory castables are high-quality, high-purity natural mullite, synthetic mullite, andalusite, bauxite, alumina, and other refractory aggregates. After meticulous material selection and crushing, the raw materials are mixed in a certain proportion according to the grade requirements. Then, the prepared mixed materials are added with the necessary binders, such as clay, tripoli, or phosphate, to improve its performance, moldability, and strength. Finally, the castable is placed and cured by the appropriate method, such as vibration and ramming, to ensure the finished product's dimensional stability and strength.

In conclusion, mullite refractory castables are an essential material in the industrial sector with multiple applications. With the rapid development of industry and technology, mullite refractory castables will continue to improve in terms of performance and production process, contributing to the progress of the industry.