Amorphous refractory materials have two kinds of dense refractory materials and heat insulation, according to the hardening process and the nature of the binder is divided into ceramic bonding (in the calcination process because of sintering and hardening), hydraulic bonding (condensation at room temperature and after hydration reaction and hardening), chemical bonding (at room temperature or lower than the temperature of ceramic bonding after chemical reaction rather than hydration reaction and hardening), Organic bond (bond or harden at room temperature or slightly higher temperature) four categories. The amorphous refractory materials can also be divided into three types according to the application type: total construction materials and repair materials, masonry and joint materials, and refractory coatings.

All construction data and repair data include:

(1) Refractory ramming material.

It can be directly constructed or used after distribution with some liquids, and is constructed by ramming method, mostly hardened under heating effect higher than normal temperature.

(2) Refractory plastic.

Delivered in flexible soft billets or irregularly shaped pellets, which can be applied directly, constructed by ramming, sensation, pressing or extrusion, and hardened during calcination.

(3) refractory castable.

Delivery with dry material, add water or other liquid distribution after use, to pour, stir, tamping method construction, if necessary, with tamping method construction, can be condensed and hardened without heating.

(4) fire-resistant spray paint.

A mixture specially prepared for use by pneumatic or mechanical eruption methods, the hardening properties of which may be classified as one of the preceding three.

Masonry and joint material i.e. Refractory mud. Construction with a spatula or similar tools, can also be used for filling or dipping blocks, hydraulic bonding, ceramic bonding and chemical bonding three.

Refractory coating is a mixture composed of fine aggregate and binder. All kinds of bonds can be used, the amount of water (or other liquids) is generally higher than the refractory mud, and the construction is carried out by hand, pneumatic tools or mechanical eruption methods.

On the basis of the above classification method, the aggregate that determines the characteristics of the mixture is further classified and named according to the properties of the main components of the mixture, such as high aluminum refractory plastic, clay low cement refractory castable and corundum ultra-low cement refractory castable.

Compared with shaped refractory products, the advantages of amorphous refractory materials are:

(1) The factory covers a small area, does not require molding and firing processes, has little energy consumption, low investment and operating costs.

(2) can significantly reduce the type and number of special-shaped bricks, easy to prepare materials and construction.

(3) The lining is good, improves the strength and air tightness, and reduces the heat loss.

(4) Equipped with metal or ceramic anchors, or reinforced with stainless steel fiber, it can improve the resistance to mechanical vibration and thermal shock, and can also partially repair the damaged part.

(5) Easy storage and transportation, conducive to the construction of furnace mechanization. Only the construction management must be strict, otherwise it will affect the physical and chemical function and life of the furnace lining. Sometimes the amorphous refractory materials are used as prefabricated components.

Data selection:

Refractory products and dense amorphous refractory materials are mainly used for the refractory layer of high temperature furnace lining, thermal insulation refractory products and light castable in addition to the refractory layer for medium temperature furnace lining, generally used between the refractory layer and the thermal insulation layer of high temperature furnace lining, or directly as the thermal insulation layer of low temperature furnace lining. There are few cases of using a single refractory material as a lining, and the common is a composite lining: the inner layer is mainly fire-resistant, and the other layers are mainly insulated from the thermal function of refractory materials. The insulation layer not only reduces the loss of heat dissipation and heat storage loss, but also improves the heating rate and cooling rate of the furnace, as well as the power, operation rate and output value of the furnace. In addition, the furnace structure is simplified and the self-weight of the furnace is minimized.

The function of refractory materials has three aspects:

(1) Mechanical function. Such as compressive strength, flexural strength.

(2) Chemical function. Such as slag resistance, reaction with controlled atmosphere.

(3) Physical function. Such as bulk density, refractoriness, load softening temperature, thermal expansion rate, reburning line change rate, thermal shock stability, thermal conductivity and specific heat capacity. According to the use of fire-resistant materials, starting from the induction of various functions needed, several kinds of fire-resistant materials are selected separately. It will be confirmed later on the basis of investment and economic benefits. In view of the fact that some important indicators (such as the service life) are not easy to quantify, they can only be placed and compared according to the degree of priority when selecting materials, so the planning experience and the application experience are still quite effective in the selection of materials. According to the furnace planning conditions and factors to be considered, the corresponding characteristics of fire resistance data are summarized in a table

(4) According to the different parts of the application, the data characteristics that need to be considered when selecting materials are shown in the table

(5) The development trend of refractory materials for furnaces is variety, data optimization and energy saving. With the development of production technology, in addition to the refractory insulation layer that has been used for furnace linings, high-temperature refractory fiber products are gradually being promoted for the refractory layer of furnace linings. The policy of material selection is: according to the type of furnace and different application parts to select the appropriate type of refractory data, at the same time improve the furnace structure planning, build multi-layer composite lining, so that each layer of data in different temperature areas close to the same period of failure, so as to extend the service life of the lining.