Refractory castable is a kind of refractory material that does not need to be formed and has good fluidity after being fired and stirred with water.
Refractory castables for reheating furnaces
Unshaped refractory materials, also known as refractory flow refractories and bulk refractories, are made up of a certain gradation of refractory aggregates and powdery materials mixed with binders and additives, without forming and firing. A type of refractory used directly in the forming and firing process.
Refractory castables is composed of refractory aggregate, fine powder, additives and binders, and is a refractory mixture formed by batching and mixing. Refractory castable is a new type of refractory material that does not require high temperature firing, can be used directly after construction and baking, and has simple production process, energy and labor saving, mechanized construction, good integrity, easy repair and long life.
There are many types of refractory castables used in different kilns and locations, the actual kiln operating conditions (operating temperature, furnace atmosphere and contact state of dust, steam and liquid/slag, etc.) and slag characteristics to determine the kiln Type and material quality of lining refractory.
Project |
Index |
|||||
ZJ-42 |
ZJ-60 |
ZJ-65 |
ZJS-65 |
ZJ-70 |
||
Al2O3%≥ |
42 |
60 |
65 |
65 |
70 |
|
Bulk density (g/cm3)≥ |
110℃×24h after drying |
2.15 |
2.30 |
2.40 |
2.40 |
2.45 |
Normal temperature flexural strength/MPa |
110℃×24h after drying |
4 |
5 |
6 |
6 |
7 |
Cold crushing strength |
110℃×24h after drying |
25 |
30 |
35 |
35 |
40 |
Test temperature×3h after burning |
40 (1300℃) |
45 (1350℃) |
55 (1400℃) |
55 (1400℃) |
55 (1450℃) |
|
Permanent linear change (Test temperature×3h)% |
-0.5~+0.5(1300℃) |
-0.5~+0.5(1350℃) |
0~+1.0(1400℃) |
0~+0.8(1400℃) |
0~+1.0(1450℃) |
|
Thermal shock resistance(1000℃ water cooling)/time |
- |
- |
- |
≥20 |
- |
|
Operating temperature℃ |
1300 |
1350 |
1400 |
1400 |
1450 |
Features of refractory castables:
Easy to construct
Excellent performance
save resources
Extend the life of the boiler
Insulation castables are mainly made up of lightweight refractory aggregates, powders, and binder additives.
High alumina castable is a refractory castable made of high alumina bauxite clinker as aggregate and refractory clay as powder, adding aluminate cement and sodium tripolyphosphate according to the formula proportion
Ceramic wear resistant castable is a special material and is a new type of material developed recently. It not only meets the needs of national defense cutting-edge products and high-tech development, but also meets the requirements of the rapid development of the national economy. Therefore, it is easier for users to accept than other materials, so it develops rapidly.
Silicon carbide castables mainly use 98 silicon carbide as the main raw material, add water reducing agent and micropowder, and use pure calcium aluminate cement as binder to make amorphous refractory materials. Cupola and other high temperature materials to be recorded.
Corundum self flowing castable is a high-tech product developed according to the theory of solid fluid and combined with the application characteristics of refractory materials, which is the first in China. The corundum self-flowing material can be degassed and leveled without vibration with the help of its own gravity, so as to achieve densification.
Refractory carstables for ladles is made of high-purity fused corundum as the main material, high-purity spinel is added to the matrix, and an appropriate amount of binder and admixture (dispersant, water reducing agent) are added.
Castables Refractory for cement kiln Castables for cement kilns are special refractory castables for cement kilns. In my country, the new dry-process cement technology is developing rapidly, and the design and brick shape of PC and SP kilns are also very complicated. In order to adapt to this situation, our factory has developed a series of new refractory castables to replace the traditional refractory materials. Practice has proved that it is more suitable to use castables in parts with complex structure and kiln body deformation. Castables are also suitable for coolers, preheaters, precalciners, kiln door covers, tertiary air ducts and other parts that require thermal insulation. Its varieties include alkali-resistant castables, high-alumina and corundum castables, heat-insulating castables, and steel fiber reinforced refractory castables. Gongyi Yuying Refractory Co., Ltd. operates: castables for cement kilns, prefabricated blocks, low cement castables, refractory mud, refractory ramming materials, corundum castables, refractory castables, steel fiber castables, steel jade castables, Refractory plastics, high alumina castables, wear-resistant castables, plastics, castables, clay castables, refractory castables manufacturers, the company has 160 employees, including 12 senior professional and technical personnel, with an annual production capacity of 60,000 tons , has light and heavy material production lines, various production, testing and testing equipment, including 10 sets of 400-ton to 1,000-ton series forming presses, two (148 meters long and 118 meters long) high temperature tunnel kiln . Castables are also suitable for use in some parts of coolers, preheaters, precalciners, kiln door covers and tertiary phoenixes. Suitable thermal insulation castables can be used in preheaters of cement kilns and other parts that require thermal insulation. The main castables used in cement kilns are: index Alkali resistant castable High alumina castable High Alumina Steel Fiber Castable High strength mullite castable Silicon carbide anti-skin castable GT-13NL G-16 GF-16 G-20G GC-13H Al2O3%≥ 35 65 65 65 55 SiO2+SiC%≥ - - - - 35 Bulk densityg/cm3≥ 2.10 2.5 2.5 2.60 2.5 Cold pressed strengthMpa≥ 110℃×24h 60 80 80 80 80 1100℃×3h 60 80 80 90 100 Flexural strengthMpa≥ 110℃×24h 6 8 9 8 8 1100℃×3h 6 8 9 9 10 Rate of change of line after burning 1100℃×3h ±0.5 ±0.3 ±0.3 ±0.3 ±0.3 1. Alkali resistant castable Experiments show that the alkali pouring material has excellent alkali resistance much better than ordinary clay or high alumina pouring material. Ordinary and low-cement alkali-resistant castables have been successfully used in double-layer structural linings for preheater roofs, cones, tertiary air ducts, etc., where shaped bricks are not suitable. The low-cement alkali-resistant pouring material can also be used in the rear kiln mouth, cooler and kiln door cover. 2. High alumina and corundum castables High alumina and corundum castables for cement kilns include low cement and ultra-low cement castables, high strength corundum castables, etc. Calcined bauxite and cut jade are used as aggregates in the castable. Low cement and ultra-low cement type high alumina castables can be used in front and rear kiln mouths, chain belts, kiln door covers and cooler side walls. 3. Insulation casting section The heat-insulating castables for cement kilns include ordinary heat-insulating castables, high-strength heat-insulating castables, and ordinary and low-cement alkali-resistant heat-insulating castables. Usually high alumina cement is used as a binder in the castable. Ordinary heat-insulating castables use expanded perlite, expanded vermiculite and waste light bricks as aggregates. High-strength heat-insulating castables use refractory clay ceramsite, fly ash ceramsite, shale ceramsite, etc. as aggregates. Alkali-resistant and heat-insulating castables use alkali-resistant lightweight aggregates. Ordinary heat-insulating castables and their prefabricated blocks can be used as heat-insulating villages in double-layer structural linings of coolers, preheaters, calciners, kiln door covers and tertiary air ducts; high-strength heat-insulating castables and their prefabricated Blocks are available as single-layer linings in the neck and disintegration zones of conventional kilns. Ordinary and low-cement alkali-resistant and heat-insulating castables can be used in preheaters in small and medium-sized kilns and other parts that require alkali-resistant heat insulation. 4. Steel fiber reinforced refractory castables Adding steel fiber can improve the dismantling strength of the castable, and greatly improve the thermal shock resistance, impact resistance and wear resistance of the castable. Our company has carried out a lot of systematic research on steel fiber reinforced refractory castables, and developed a series of steel fiber reinforced refractory castables.
Corundum refractory castable has the characteristics of high strength and good fluidity, which is convenient for construction. It is mainly used for the parts that are easy to be washed and worn, such as the combustion chamber, separator and flue of circulating fluidized bed boiler.