Do not know the construction method of refractory castable?Learn together

What is amorphous refractory?Amorphous refractory material is composed of refractory aggregate and powder, binder and admixture with certain size gradation.Used for lining of thermal equipment, without firing process, directly used for baking.Compared with firebrick, it has the characteristics of simple process (because of eliminating burning process), energy saving, low cost and convenient mechanized construction.The effect is better than firebrick in some thermal equipment.So, what is the classification of amorphous refractories?Look for refractory net to look together below.

Classification of amorphous refractory castable

According to construction methods and material properties, amorphous refractory materials can be divided into castable, plastic, ramming, gunning, projection materials and coatings.

castable

A material with good fluidity after stirring with water.Need to pass proper curing after forming, make its coagulate, harden, can be used after baking according to certain system.

Castable material is aluminum silicate clinker, corundum material or basic refractory clinker.Lightweight castable to expand perlite, vermiculite, ceramsite, alumina hollow ball as aggregate.Calcium aluminate cement, sodium silicate, ethyl silicate, polyaluminium chloride, clay or phosphate etc.Admixture depends on the use of conditions, its role lies in improving construction performance and physical and chemical properties.

The construction molding methods of casting materials include vibration method, pump injection method, pressure injection method, jet method, etc.The casting material is used as an integral lining, often in conjunction with metal or ceramic anchors.Such as adding stainless steel fiber reinforcement, can improve its resistance to mechanical vibration and thermal shock capacity.The casting material is used as the lining of various heat treatment furnaces, ore roasting furnaces, catalytic cracking furnaces, conversion furnaces, melting furnaces and high-temperature melt flow tanks, such as lead and zinc melting furnaces, tin tanks, salt bath furnaces, steel or iron discharge tanks, steel casks, vacuum circulation degassing device nozzles, etc.

plastic

A plastic clay material or billet.When appropriate external force is applied, it is easy to deform without cracking.When the stress is relieved, no deformation occurs.But the plastic material has the semi-silicon quality, the clay quality, the high aluminum quality, the zirconium quality, the carbon quality and so on, also has the light weight may the plastic.Plastic must be added to plasticizing materials, plasticizing materials are mostly highly plastic clay, plasticizer can be used to improve the plasticity of this clay.Plasticizer has carboxymethyl cellulose, dextrin, lignin sulfonate and so on.Plastic can be used by the binder can be plastic clay, phosphoric acid, aluminum dihydrogen phosphate, aluminum sulfate, and so on.Add phosphoric acid or phosphate binder aluminum oxide plastic, preservation process will occur with alumina chemical reaction, the formation of insoluble aluminum orthophosphate and make the mud hardening, so to add preservatives, such as oxalic acid, citric acid, acetylacetone, etc.

Generally, the construction method is ramming or vibration.Metal or ceramic anchors must be provided for integral lining construction with plastic.Plastic can be used as lining of soaking pit, heating furnace, boiler and other thermal equipment, and also used to wrap up the cooling pipe of heating furnace.

Spray paint

A refractory mixture sprayed or sprayed by a jet.According to the gunning method can be divided into wet gunning (or mud gunning), semi-dry gunning and fire (flame) gunning.Wet spraying with compressed air can deliver the slurry containing 20 ~ 40% refractory powder, which can achieve higher fog dispersion, high adhesion rate and even thin layer spraying.Semi-dry spraying is to add water at the nozzle to moisten the refractory powder which is sprayed by compressed air. The water amount is 11 ~ 14%, the adhesion rate is low, and the thick layer can be sprayed.Fire gunning belongs to dry gunning, which delivers the gunning material to the flame of the fuel-oxygen lance. The gunning material is partially melted in the nozzle flame and attached to the brick lining.

Gunning material material has aluminum silicon, aluminum silicon zirconium, magnesium, magnesium calcium, magnesium chromium and so on.The binders used are sodium silicate, phosphate, polyphosphate, asphalt, resin, etc.In order to improve the adhesion rate, clay, bentonite, lime and other additives are added.In order to ensure good sintering, sintering AIDS, such as serpentine, pure peridot, lime, refractory clay, iron oxide and so on, are added.

Refractory coating

Material applied to the lining of firebrick.According to the different application requirements and construction methods, fire-resistant coatings can be prepared into paste and slurry.The binder used varies from material to material. For example, phosphate, polyphosphate and magnesium sulfate are prepared as basic coatings for continuous casting tundish.Clay, aluminum dihydrogen phosphate, aluminum chromium phosphate, sodium silicate, etc.In order to improve the coating coating, generally add plasticizer and other additives.The coating is mainly used for protecting the lining of all kinds of thermal equipment or repairing the local damage of brick lining.

Ramming material

A loose refractory with little or no plasticity.Materials are silicon, clay, high aluminum, jade, zirconium, silicon carbide, carbon, magnesium and so on.According to the material and use conditions of the ramming material, inorganic binder or organic binder similar to the casting material can be used, such as water-soluble dextrin, carboxymethyl cellulose, lignin, sulfonate, polyvinyl alcohol;Water resistant and thermal plasticity of paraffin, asphalt, tar, phenolic resin, random polypropylene, etc.

Ramming material used by the ramming construction, the porosity is lower, the density is higher, therefore, in the amorphous refractory material, ramming material is particularly suitable for melting furnace lining and holding high temperature metal liquid lining of various containers.Such as open hearth and electric furnace hearth, all kinds of induction furnace lining, blast furnace ditch, sheng steel drum, etc.

Casting material

A semi-dry clay lining cast by a projector.Mainly used for building integral steel drum lining.The materials are silica, waxite, clay, high alumina and zircon.High silicon and high aluminum projectors are more commonly used.

The above is about the classification of refractory castable and construction of some methods, if you want to know more information, call yuneng furnace technology consulting telephone: 05335331887 for more information