Refractory material is always made on the basis of mineral raw materials. In the process of using construction or industrial refractory materials, as well as during prolonged use, no changes occur in their structure. It is for this reason that "refractory" is often used in various fields of activity, having confidence that the construction will turn out to be reliable and durable.
Properties of refractory materials
The presented materials are used in everyday life in many areas. Refractory material is used in a variety of metallurgical processes. These include melting, annealing, calcining, evaporation and distillation. Also, do not forget that the materials presented retain their original properties even when processed at high temperatures.
Refractories that were previously used in production and require re-processing are called scrap. Such materials are most often recycled, creating a new product. It is the refractory material that differs from others in increased strength at high temperature, as well as chemical inertness. As for the composition, the materials presented are ceramic mixtures of refractory oxide, silicate, carbide, nitride, and also boride.
Refractory classification by shape and size
Refractory material can be classified by the following shapes and generally accepted sizes:
- Wedge refractories of normal size.
- Direct materials of small and huge formats.
- Simple shaped.
- Especially difficult.
- Large-block materials that have a mass of more than 60 kilograms.
- Special laboratory or industrial refractories. These include tubes, crucibles.
Classification of refractories by the method of formation
You can distinguish the main types of refractory materials by the method of formation:
- Hot pressing materials.
- Thermoplastic pressed.
- Cast molten refractories from melt, which are obtained using electric smelting.
- Semi-dry materials derived from powder.
- Plastic molding refractories, which are made using a special mass in a plastic state. For these purposes, a special machine molding and subsequent prepress is used.
- Cast refractories, which are obtained by casting from a liquid slurry, as well as a foam slurry.
- Sawn refractories made from natural rock or pre-made blocks.
What should be used for furnace equipment?
Refractory material for the furnace will be an excellent option that can be used in construction. All this was made possible thanks to a unique combination of chemical, physical, as well as mechanical properties. The presented material is able to withstand the effects of high temperature, and most importantly, even in case of fire it will not melt and will not change its shape.
For the construction of the furnace, high refractory materials of the highest rates can be used. By their properties, they have low porosity. During production, specially designed technology is used, therefore the refractory material for the furnace is able to withstand high temperature conditions.
The manufacturing process begins with obtaining a powder that has a specific particle size distribution. Such unique properties can provide a slight reduction in volume during processing.
Advantages and scope of fire-resistant drywall
Refractory sheet materials are used most often for construction. Today, fireproof gypsum board, which is a double sheet of cardboard and gypsum filler, is in great demand. During production, a fairly dense and extremely flexible construction board is used, which includes a large number of layers.
Also, do not forget about a certain technology for manufacturing a gypsum heat-resistant core. The gypsum plasterboard refractory sheet can be used for a variety of industrial premises, where a characteristic unstable level of humidity is observed, and also elevated temperatures were recorded. Refractory sheet materials and fire-resistant types of drywall have a large number of advantages:
- Increased fire resistance.
- Excellent sound insulation performance, especially if drywall is used in combination with other special building materials.
- Low cost, ease of installation, as well as ease of use.
- Small dimensions of fire-resistant boards that exactly match the dimensions of a standard type sheet. It is these capabilities that allow you to combine them in one room if necessary.
- Minimum indicators of acidity.
What are the refractory materials for walling?
Refractory materials for walls are presented in a large assortment. Refractory concrete, which is an excellent and safe material, is in special demand. It is able to withstand high temperature conditions.
Such a product has a total porosity of 45 percent or more. At the same time, its main purpose is to use it as thermal insulation. Cement is a fine unshaped refractory that tends to harden after mixing powder and liquid. Increasingly, people are buying exactly these building mixtures.
Recently, other refractory materials for walls appeared on the construction market, for example, concrete mass, coating material, concrete mix and many others.
How are refractory materials produced?
The process of manufacturing fire-resistant materials begins with a thorough preparation of the necessary raw materials. Workers at the factory manually select all kinds of impurities. The next stage is grinding, sieving, and also preparing the mixture. In this case, it is necessary to adhere to a strict dosage of all components.
The most important point during manufacturing is shaping, drying, firing, and selection. In any case, the production of refractory materials should begin with the selection of the optimal raw material. It must be enriched and crushed. It is worth noting that there are two types of raw materials - natural and artificial, which is selected in accordance with the compatibility of chemical and mineralogical compositions. Particular attention is paid to the structure of raw materials for further production.
Refractory brick for the construction of the bath
At the construction planning stage, it is necessary to carefully choose refractory materials for the bath. In no case should they expand during strong heating, as well as deform. As an example, the fact that the metal during masonry furnace is used only in strictly designated areas. That is, where its ability to expand will not affect the strength of the entire structure.
During construction, everyone should remember that ordinary clay red bricks will not be able to withstand sufficiently high temperature conditions. They will melt and eventually simply crumble. That is why all places that, to one degree or another, are exposed to high temperature, must be lined exclusively with refractory bricks.
A large number of people are aware of the unique properties of refractory materials that can withstand even maximum heat. Refractory brick has a yellowish-sand color and a granular structure. On the market, it is presented in a rectangular and wedge-shaped form. That is, they distinguish between end and rib bricks.
The presented brick is placed exclusively on a mortar, which is a mixture of fireclay and refractory clay. All seams consisting of mortar can also withstand high temperature conditions (up to 1700 degrees Celsius). Over time, they will not crumble and give in to deformation.
Porosity classification of refractory materials
The material has its own porosity, so a special classification was intended for each type:
- Particular density includes open porosity of up to 3 percent.
- High density rates - up to 10 percent.
- Dense materials have an open porosity of up to 16 percent.
Next, you can highlight:
- Sealed.
- Medium Density Materials.
- Low density.
- Products with high porosity.
- Ultra porous materials.
Production Features
The process of molding the materials presented is carried out using the method of semi-dry or hot pressing. For work, plastic molding, casting, vibrocasting, and also cutting can be applied. Previously, blocks or rocks are prepared for work.
In the manufacturing process of lightweight refractory materials, manufacturers use gas injection, burnout additives, and many other methods. Unshaped materials are most often hardenable by introducing a mineral or organic binder. We can distinguish the nature of heat treatment - these are burnt materials and non-burnt ones. It should be noted that the total temperature of the heat treatment of the non-fired material should not be more than 600 degrees Celsius. If further firing is required, it is necessary to combine the heating of the thermal unit where this or that material is used.
For fired refractory material, the total processing temperature should be more than 600 degrees Celsius. Only in this way can all the necessary physical and chemical properties be achieved.