In the field of high temperature industry, refractory plays an indispensable role, and refractory mud, as an important part of it, has become the key material to ensure the normal operation of high temperature equipment because of its unique performance and wide application. In this paper, the characteristics, types, applications and related technical parameters of refractory mud will be discussed in depth to help readers fully understand this important material.

I. Definition and function of refractory mud

Refractory mud is an unshaped refractory used for building refractory bricks, repairing lining and coating high temperature furnaces. It is usually composed of refractory aggregate, powder, binder and admixture, and has good cohesiveness, fire resistance and erosion resistance. The main function of refractory mud is to fill the gaps between refractory bricks and ensure the integrity and sealing of furnace lining, thus improving the service life and operating efficiency of furnace.

II. Characteristics of refractory mud

High bonding strength: refractory mud can be closely combined with refractory bricks to form a solid lining structure. This high bonding strength makes the refractory bricks difficult to fall off or loosen in high temperature environment, ensuring the stability of the furnace.

Low thermal expansion coefficient: At high temperature, the thermal expansion coefficient of refractory mud is low, which means that it can better adapt to temperature changes and reduce cracks and deformation caused by thermal expansion and cold contraction.

Small linear change of heating: the linear dimension of refractory mud changes little during high temperature heating, which helps to maintain the integrity and sealing of furnace lining.

Particle size standard: The particle size of refractory mud is strictly controlled, which usually requires passing certain screening standards to ensure its fluidity and filling performance during construction.

Good construction performance: refractory mud has good workability and plasticity, which is convenient for construction workers to carry out masonry and repair operations. At the same time, its curing time is moderate, which can meet the needs of different construction environments.

III. Types of refractory mud

Refractory mud can be divided into many types according to the chemical composition and temperature. Common ones are:

Clay refractory mud: The main component is clay, containing a certain amount of alumina (Al₂O₃). Its fire resistance is generally around 1710℃, and it is suitable for the low temperature furnace parts, such as the masonry of thermal insulation bricks.

High alumina refractory mud: contains a high proportion of alumina, and its content is usually above 42%. The refractoriness of high alumina refractory mud is high, which can reach above 1730℃. It is suitable for building and repairing high temperature furnaces, as high as the connection of aluminum bricks.

Aluminum silicate refractory mud: aluminum silicate is the main component, which has good acid corrosion resistance and is suitable for chemical furnaces and other occasions with high requirements for acid resistance.

Magnesia refractory mud: the main component is magnesium oxide, which has good alkaline corrosion resistance and is often used for lining masonry in alkaline environments such as cement kilns.

IV. Application of refractory mud

Refractory mud has a wide range of applications, covering almost all high-temperature industrial fields. The following are its main applications:

Furnace masonry: refractory mud is the key material for building refractory bricks. Whether it is industrial furnace, cement kiln or glass melting furnace, refractory mud can ensure the close connection between refractory bricks and form a solid furnace lining.

Repair of furnace lining: During the use of the furnace, the furnace lining may be cracked or damaged due to high temperature erosion, mechanical impact and other reasons. Refractory mud can be used to repair these damaged parts quickly and prolong the service life of furnace lining.

Coating material: In some high-temperature furnaces, refractory mud can also be used as a coating material and coated on the furnace wall to play the role of heat insulation, heat preservation and corrosion resistance.

V. Construction of refractory mud and matters needing attention

Preparation for construction: Before construction, the surface of the furnace should be cleaned to ensure that it is clean, dry and free of oil pollution. At the same time, choose the appropriate refractory mud type and construction tools according to the design requirements.

Mixing and daubing: mix the refractory mud with proper amount of water, and daub it after mixing evenly. When daubing, it is necessary to ensure the uniform thickness and full filling of refractory mud to avoid cavities or gaps.

Curing and curing: After the refractory mud is coated, it needs to be cured and cured properly. Usually, refractory mud can be cured in natural environment, but in order to improve its strength and performance, appropriate heating measures can also be adopted for maintenance.

Precautions: During construction, attention should be paid to avoid too much contact between refractory mud and water, so as not to affect its performance. At the same time, construction personnel should wear corresponding protective equipment to ensure construction safety.

VI. Market and development trend of refractory mud

With the continuous development of high-temperature industry, the market demand for refractory mud is also increasing year by year. Especially in emerging industrial fields, such as new energy, aerospace and so on, higher requirements are put forward for the performance of refractory mud. In the future, the development trend of refractory mud will focus on the following aspects:

High performance: research and develop refractory mud with higher fire resistance, stronger corrosion resistance and better construction performance to meet the use requirements in extreme environments such as high temperature, high pressure and strong corrosion.

Green environmental protection: under the background of increasingly strict environmental protection policy, develop low pollution and low energy consumption refractory mud production technology and products to reduce the impact on the environment.

Intelligent construction: combined with modern information technology, develop intelligent refractory mud construction equipment and technology to improve construction efficiency and quality and reduce labor costs.

As an important material in high temperature industry, refractory mud plays an irreplaceable role in modern industry with its excellent performance and wide application. With the continuous progress of science and technology and the constant change of market demand, the future development of refractory mud will be more exciting.