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The professional service team provides all-wave product services, including product consultation, case studies, site guidance, engineering design and etc. All products have passed ISO Quality System Certification and strictly implement CE standard of EU and national product standard of China.

1. Brief introduction of aluminum silicate
Aluminum silicate fiber product is a kind of fibriform light fireproof material developed from early 60's. It belongs to amorphous (glass state) fibers according to its structure.
It is made of the synthetic materials of hard clay clinker or industrial alumina powder and silica powder as raw material which will be fiber by compressed air blowing (or thrown silk method) through electric arc furnace or electric resistance furnace melting. Its main chemical compositions are aluminum oxide (30-55%) and silicon dioxide. Moreover, it can be made into blanket, felt, board, paper, rope and a variety of precast block and units and etc after processed.

2. Classification and characteristics:
2.1 Low-temperature aluminum silicate fiber: Generally the A1203 content is greater than 40%. It has the features of low production cost, high shrinkage rate and no strict request on inimical impurity content, etc. Its price is just a little higher than that of mineral fibers, but its heat resistance is better than mineral wool. With 700-800 of working temperature, it offers favorable conditions for composite lining of industrial furnace and solves the 700-900 gap which can not be endured by common fibriform insulation materials.
2.2 Ordinary aluminum silicate fiber: Its raw material is natural hard clay clinker. Content of fiber A1203 45%, and content of inimical impurities is 3%-4%. The operating temperature of fiber is 1000.
2.3 High-purity aluminum silicate fiber: Its raw material is the synthetic materials of industrial alumina powder and silica powder. Its content of inimical impurities<1% and the operating temperature of fiber is 1100 which is higher than that of ordinary aluminum silicate fiber and also applicable for reducing atmosphere.
2.4 High-aluminum fiber: Its raw material is the synthetic materials of industrial alumina powder and silica powder. Content of fiber A1203 55% and content of inimical impurities<1%. Because of high content of fiber A1203 and the ratio of A1203 and SiO2 close to mullite composition, the crystallization of cristobalite is lessened, and its heat resistance and thermal shock resistance are improved. The operating temperature of fiber is 1200.
2.5 Chromium aluminum silicate fiber: It is also called chromium stable fiber because it can restrain crystallized changes of amorphous fiber at heating by adding 3%-6% chromic oxide into the synthetic material of high-purity aluminum silicate fiber. The operating temperature of fiber is 1200.
2.6 Zirconium aluminum silicate fiber: Adding zircon sand into the synthetic material of high-purity aluminum silicate fiber makes the ZrO2 content up to 12%-15%. The operating temperature of fiber is 1300.

3. Main production methods and process flows
3.1 Main production methods
The melting for raw materials of aluminum silicate fiber generally uses electric furnace as melting unit, mainly two types-electric resistance furnace and electric arc furnace. The molding method of fiber is divided into blowing, thrown silk, and thrown silk -- blowing, and so on.
3.2 Process flows
Electric arc blowing into fibers and wet felting process:
The qualified concerted material is molten in electric arc furnace to form stream which will be fibers through compressed air or steam injection, then become finished fibers after deslagging in slag separator. After swirl deslagging in agitator tank, the finished fibers are sent to storage tank and stuck binding agent to form sizing agent. Finally, the sizing agent is dried through presser stamping or vacuum suction filtration into aluminum silicate wool products.
Electric resistance blowing (or thrown silk) into fibers and dry needling felt process:
According to different fiber forming means, the dry needling blanket of aluminum silicate fiber has two production processes: electric resistance injection (including flat and upright blowing) into fibers and dry needling felt technology, and electric resistance thrown silk into fibers and dry needling felt technology.
"Needing felt" is made by drawing lessons from non-woven needling technology.
When bulk fiber is sent to needle machine for needling, the fiber layers are tightly
interwoven because of hooked stitch on pricking pin to improve its tensile strength and anti-wind erosion.

4. Standard index of aluminum silicate wool and its products
Physical properties of product index stipulated by GB/T 16400-1996 < Aluminum silicate wool and its products for heat insulation> are: length, width, thickness, density, water content, slag ball content, thermal conductivity (average temperature 500), tensile strength, shrink rate of heater wire and etc. In addition, the chemical composition of different types of wool is not exactly alike.

5. Performance comparison of aluminum silicate fiber roll-felt and shell of pipe Aluminum silicate fiber roll-felt is made through molten injection whose fiber is longer than that through the common molten injection. Inside the products, the fiber will be interwoven into more closed small "air-chamber", i.e. air hole, so its thermal conductivity is lower and heat preservation is better than that by the common molten injection. The fiber arrangement in shell products is between spreading in layers and bond, which is much different from that in roll-felt, which is close to spreading in layers. Its thermal conductivity is greater and heat preservation is a little worse than that of roll felt. We can illustrate this point through the following calculations:
Generally the temperature of steam pipelines is about 500, and here we take 500, annual average environmental temperature 20, temperature of insulation external wall 40, annual average wind speed 2m/s, and we take pipeline 630 for example.
Suppose the insulation thickness is 100mm.
The average temperature of insulation layer is 270, and the thermal conductivity of roll felt m=0.086w/mk
Thermal conductivity of shell of pipe m=0.1065 w/mk
(bulk density of roll felt 100kg/m³, bulk density of shell of pipe 128kg/m³)
Qualitative temperature is 30, and the air constant =0.0267 w/mk =18.6*10-6
By calculating Gr* Pr=1.014*109 we can look up from the table c=0.13 n=1/3
By calculating Num=130.597
And free convection heat transfer coefficient aw=4.201w/m²
By calculating Re=103750 we can look up from Re table A=0.0239 n=0.805
By calculating Nu=259.277
And forced convection heat transfer coefficient acw=8.34w/m²
Radiation loss +acw(40-20)
=370.8w/m²
The insulation thickness of roll felt calculated by equation of heat conduction =94.5mm<100mm
The insulation thickness of shell of pipe=113.4mm>100mm
This result shows that in the same medium temperature, environmental temperature and external wall temperature, etc, the insulation thickness of roll felt is less than that of shell, so roll felt can save more materials. In the same insulation thickness, the external wall thickness of roll felt is less than that of shell, so its radiation loss is low and heat preserving effect is more obvious. View at bulk density, roll felt achieves the effect of shell with less material which indicates furnace and pipe network to become lighter.