Grade classification of aluminum silicate needle punched blanket
1.With the same temperature level of raw materials for aluminum silicate acupuncture
Ordinary fiber blanket use flint clay as raw materials. Standard needled blanket use coal
gangue as raw materials, high purity temperature blanket must use alumina powder and
quartz sand as raw materials(iron,potassium,sodium should be controlled less than 0.3%),
high aluminum blanket temperature is made based on high purity material with increasing
the aluminum content to 52-55%. High Zirconium products add zirconia content (15-17% ZrO2).
The purpose of ZrO2 is to prevent the reducibility of amorphous fiber in aluminium silicate fiber
at high temperature reduction, reaching its high temperature stability.
At present,the so-called high aluminum products made by small manufacturers is another
approach, namely adding alumina powder used in coal gangue,but its impurities content in
coal gangue (iron, potassium and sodium are usually more than 1.5%) exceed the standard
request,it is unable to raise the level of the fiber, because the melting point of the impurities
is generally about 1300 degree Celsius, which will make the silicon aluminum system to form
a eutectic melt at low temperature, so as to reduce the use effect in actual use.
2.Difference between heat insulating materials and refractories:
General speaking, below 1570 degrees Celsius is called thermal insulation materials;
more than 1570 degrees Celsius is called refractory material. Traditional refractory
materials generally refers to heavy refractory bricks, castable, etc., the bulk density in
The advantages of aluminum silicate fiber is obvious, with excellent insulating properties
under the premise, but also has very good fire resistance, and belongs to the light material,
reduce the load of the furnace body, greatly reduce the traditional materials’ installation
because of the large amount steel consumption to support heavy materials.
3. Distinction of temperature grade
1050C working temperature 950C
1260C working temperature 1000-1050C
1260C High Purity working temperature 1100C
High Aluminum working temperature 1200-1250C
Zirconium content working temperature 1200-1250C
High Zirconium working temperature 1300-1350C
4.Recommended selection habits of industrial furnace
The furnace is relatively stable, does not basicly consider the temperature allowance; gas and
fuel stove because the atmosphere is relatively unstable, so the general consideration about
150 degrees allowance; coal-fired stoves generally do not recommend the use of ceramic fiber.
5. Permanent Linear Shrinkage
P evaluation of heat resistance (working temperature) of ceramic fiber products. International
uniform provisions of ceramic fiber products in the non-load heated to a certain temperature,
holding high temperature line shrinkage of 24 hours, said ceramic fiber heat resistance.
P heating linear shrinkage value is ≤3% for the continuous use temperature of aluminum
silicate fiber products. Amorphous ceramic fiber crystallization, grain growth rate at this
temperature slowly, fiber elastic stable performance.
P Heating wire shrinkage value ≤ 3% for the continuous use temperature of aluminum silicate
fiber products.Amorphous ceramic fiber crystallization, grain growth rate at this temperature
slowly,fiber performance stability and flexibility.
P Heating linear shrinkage value ≤ 4% of the tested temperature is the maximum
temperature of ceramic fiber.
6. Thermal Conductivity
P coefficient of thermal conductivity is a physical property of the material, and it is the only
index to characterize the thermal insulation performance of ceramic fiber.
P depends on the structure, bulk density, temperature, furnace atmosphere, humidity and
other factors of aluminum silicate fiber products.
P ceramic fiber is composed of solid fiber and air mixture structure, its porosity rate of 93%.
A large number of low thermal conductivity air is filled with air holes, and the continuous
network structure of solid molecules is destroyed to obtain excellent thermal insulation
performance. And the smaller the diameter of the pores, the more the number of pores in
the closed state along the direction of the heat flux, the better the thermal insulation
property of the ceramic fiber.
7. Aluminum silicate fiber products, chemical properties
Chemical composition directly determines the fiber's heat resistance:
1) Al2O3, SiO2, ZrO2, Cr2O3 and other active ingredients ≥ 99%, high-temperature oxide
content, directly determines the performance of ceramic fiber.
2) Fe2O3, Na2O, K2O, MgO and other impurity ingredients ≤ 1%, are harmful impurities,
a direct result of the deterioration of ceramic fiber performance.
8. Environmental protection and energy conservation
Ø Improve the working environment of workers, reducing the waste of natural resources and
Ø high heat sensitivity, the industrial furnace to achieve the computer control
Ø Compared with refractory bricks or refractory castables:
Reduce energy consumption by about 15-25%, increase production by about 3-5%.
Ø Brush the surface coating, radiation than conventional refractory materials increased by nearly
11%, can effectively improve the furnace heating rate, shorten the furnace operating cycle, improve
the furnace operating rate and operating flexibility.
Matrix Industry China Limited
Professional manufacturer of Aluminum Silicate Refractories Fiber Materials in China.
Mobile & WhatsApp: +86 189 0643 2821