Several types and product characteristics of amorphous refractoriesRelease date：2019-11-12 18:30:51 Page View：6637
Amorphous refractories (also known as bulk refractories or integral refractories) are defined as refractories with a certain gradation of aggregate and powder, binder and admixture, which are of uncertain shape and do not require high temperature firing for immediate and direct use. Amorphous refractories should generally be no less than 1500℃, but some insulation amorphous refractories are allowed to be less than 1500℃. Amorphous refractories usually have an unfixed shape, which is in the form of loose, slurry or clay paste. In addition, amorphous refractories can also be made into prefabricated blocks to use or form a seamless integral structure, so it is also known as integral refractories.
Amorphous refractories are characterized by simple production process, short production cycle, energy saving, good integrity in use, strong adaptability and convenience in mechanized construction.
Classification and composition
Amorphous refractory is composed of refractory aggregate and powder, binder, admixture, etc., the amount of which should be determined according to the type and use of amorphous refractory. Under normal circumstances, the amount of aggregate is more than 60%. 35%, 8% binder, right? 15%, admixtures usually less than 1%; How much water (or liquid) is used? 12%. Of course, the amount of various components depends entirely on the variety and use, individual very far, such as low cement refractory castable as a binder for cement use and water consumption are lower, and the amount of refractory slurry water (or liquid) is greatly increased.
There are many kinds of amorphous refractories and different classification methods. Amorphous refractories are mainly classified according to their construction characteristics, but also according to their porosity, the type of binder used and the material of refractory aggregate.
According to porosity classification: there are two types of dense amorphous refractory and heat insulation amorphous refractory. Dense amorphous refractory is also known as ordinary or heavy amorphous refractory, heat insulation amorphous refractory is also known as lightweight amorphous refractory. According to the international standard (ISO1927 -- 75) classification, the insulation amorphous refractory lining after drying samples porosity should be no less than 45%.
According to the type of binder classification: according to the chemical properties of the binder can be divided into inorganic binder amorphous refractories and organic binder amorphous refractories. According to the hardening mode of the binder, it can be divided into gas hardware binder, hydraulic binder, heat hardness binder and other types of amorphous refractory.
According to the aggregate material classification: the aggregate has dense aggregate and heat insulation aggregate. Dense aggregates are mainly clay, high aluminum, silicon, magnesium, dolomite, spinel, chromium, zirconium, carbon, silicon carbide and other varieties. In addition still have the heat insulation aggregate of all sorts of material material, basically have pumice stone, drift bead, vermiculite, pottery grain, expand perlite, porous clinker and alumina hollow ball to wait, also can use heat insulation refractory product or fragment to make heat insulation aggregate.
According to the classification of construction characteristics: there are mainly fire-resistant castable, fire-resistant spray coating, fire-resistant shotcrete, fire-resistant plastics, fire-resistant ramming materials, fire-resistant injection materials, fire-resistant projection materials, fire-resistant daub materials, fire-resistant mud and dry vibrating materials.
(1) refractory castable. Refractory castable also known as refractory concrete or refractory casting materials, refractory aggregate and powder materials and appropriate binder, admixture prepared, has a good thixotropic performance, generally by pouring or pouring vibration method construction.
(2) fire-resistant spray coating and gunning material. The composition of fireproof spray coating and gunning material is close to that of fireproof castable, and the particle gradation should meet the special requirements of spraying or gunning construction. There is not much difference between fireproof spray coating and gunning. Gunning is named because it is used to repair lining.
(3) refractory plastics. Refractory plastic with refractory aggregate and powder and appropriate binder, admixture from the mud billet shape or irregular material shape, in a certain period of time can maintain a good plasticity, generally using pneumatic ramming tools construction.
(4) refractory ramming material. Fireproof ramming material with fireproof aggregate and powder and appropriate binder, admixture and so on preparation, is loose form, with strong ramming method construction.
(5) refractory pressure injection. Fireproof pressing material is made up of fireproof aggregate, powder, binder and admixture, which is in the form of paste or mud.
(6) refractory projectiles. Refractory projectiles are made of refractory aggregate, powder, binder and admixture.
(7) refractory coating. Refractory coating (also known as daub) with refractory fine aggregate and powder or only with refractory powder to join the appropriate binder, admixture preparation. Its water content (or other liquid) is high, with manual or pneumatic machine daub or spray construction. The difference between fireproof coating and fireproof spraying coating and fireproof spraying material lies in particle fineness and construction thickness.
(8) refractory mud. Refractory mud also known as masonry and joint materials, refractory powder and appropriate binder, admixture from the variety of ceramics combined with refractory mud, hydraulic refractory mud and chemical combination of refractory mud, with spatula or similar tools construction.
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