In the range of unshaped refractory materials, there are roughly four common types with fire-resistant and wear-resistant properties:
1. Wear-resistant and plastic
Wear-resistant plastic is a high-aluminum, corundum granular product. Compared with traditional refractory plastics, it has excellent properties such as easy construction, good efficiency, good molding, and high strength. The material is composed of adhesives, refractory aggregates and hardening accelerators, and a certain proportion of PA glue is added to form a plastic Refractory mud is convenient for the construction of various complicated parts. It is a gas-hardening material with low-temperature hardening performance to ensure the abrasion resistance of circulating fluidized bed boilers. The wear resistance is poor.
1) How to use
When in use, use a forced mixer to stir. Add the coagulant evenly during stirring. After dry stirring for 1 minute, add 4-5% adhesive and stir for 3 minutes. When the material is plastic, it can be discharged for use.
Use rubber hammer ramming construction or machine ramming construction, the construction time can be guaranteed after 30 minutes, and the initial setting time is about 1 hour.
During construction, pave the plastic to a certain thickness, generally not more than 60mm thick. If the construction is interrupted, the ramming surface should be covered with plastic sheet to prevent rapid drying. The construction time of the wear-resistant plastic can be about 30 minutes after mixing (it will vary with the ambient temperature). Once it hardens for a long time, it should be thrown away and cannot be used.
2) Applicable area
The application range is wide, and the materials and bonding agents used can be selected according to the conditions of use. It can be directly poured into a lining body for use, and can also be used as a prefabricated block by pouring or vibrating method.
Suitable for high temperature areas with low friction, such as boiler bottom air chamber, primary air duct, return riser (leg), returner, return pipe, tail flue furnace wall, slag cooler, tail flue Filling of each furnace door, etc.
3) Storage method
It is generally stored in a dark and cool place, and the shelf life is about 2 to 3 months.
2.Wear-resistant and refractory plastic
Wear-resistant and refractory plastics are made of high-bauxite clinker, corundum, mullite and silicon carbide as aggregates. They have excellent wear resistance, super adhesion and higher use temperature. They use different binders and The refractory material with high wear resistance, which is formulated with admixture, has the advantages of convenient construction, good plasticity, and good wear resistance. The wear layer after construction has high strength and wear resistance, which can fully meet the requirements of boilers. Performance requirements for wear-resistant refractory materials.
1) How to use
The materials and binding agent are mixed with phosphoric acid and used evenly. The ramming process is usually used for construction.
2) Applicable area
It is suitable for the construction of parts with thin thickness such as the water wall of the furnace, and is mainly used in the dense phase area of the furnace and the steam-cooled and water-cooled cyclone separators. The wear-resistant and refractory material in this area is designed as a single-layer ramming structure, which is fixed by wear-resistant pins, and its design thickness is relatively thin, and it is directly laid on the construction surface.
Application in repairing circulating fluidized bed cyclone separator: its super bonding performance can repair any irregular wear parts at will, without the use of steel templates or molds, it can be ignited immediately after construction, without special maintenance, thus shortening The construction period saves costs.
3) Storage method
Avoid storage in the open air to prevent direct sunlight. It should be stored in a cold and humid place in summer and protected from freezing in winter.
3. Corundum is wear-resistant, fire-resistant and plastic
It belongs to the field of high temperature wear-resistant refractory materials. The raw materials are composed of high-alumina homogeneous materials, alumina powder, silica powder, clay, phosphoric acid, aluminum dihydrogen phosphate solution, and pure calcium aluminate cement. It is characterized by the use of synthetic homogeneous materials with low water absorption, low porosity and high uniformity to replace the traditional natural raw materials or corundum composite raw material system of sintered bauxite clinker with high water absorption, high porosity and poor uniformity. High-quality corundum, high-strength, wear-resistant and plastic.
