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Different refractory products
The refractory products show proper chemical,
mechanical, and heat resistance in temperatures higher
than 1000 degree C, the elements than show refractory
properties include:Aluminum(Al),Silicon(Si),Magnesium(Mg),
calcium(Ca),Tantalum(Ta), Lanthanum (La),Thorium(Th).
The refractory elements are mainly used in steel
manufacturing industries. All industries in which the
products are manufactured at temperatures above 1000
degrees C used these materials among which we can name
steel and foundry industries, cement industries,
petrochemistry, ceramic and glass industries, and lime
burning. The most important properties of refractory
materials are: 1-to protect the stove bodies, glass made
reservoirs and filtering canals against flame and melted
materials 2-to reduce the rate of heat transfer to out
side of the stove 3-to absorb heat, preserve it in long
term, and transfer it to the melted material. 4- to act
as the main protector of metal melting stoves against
heat shocks and tensions 5- to increase the heat
efficiency of heating operation stove.
One of the main
specifications of refractory materials is the heat
resistance they show in high temperatures which
principally depends on the chemical composition of their
crystal shaped structure. The heat resistance of
aluminum contained refractory materials directly depends
on the percentage of their aluminum. For instance the
fire clay contains 18% to45% Al2O3
and its heat resistance reaches 2050degrees C. other
important particulars of refractory materials include:
good chemical resistance, resistance toward heat shocks,
resistance against attrition, porosity heat transfer,
crystal structure and etc.
Principally the
refractory materials are categorized based upon chemical
condition of the environment I which they operate;
degree of showing refractory specifications, or the
composition of their primary substances.
The main refractory
material’s which are globally used are as follows:
1-
siliceous refractory materials
2-
magnesium refractory materials
3-
dolomite contained refractory materials
4-
graphite contained refractory materials
5-
chromite contained refractory materials
6-
bauxite contained refractory materials
7-
silimanite refractory materials
8-
refractory materials
9-
fire clay
10-
Silicon carbide refractory materials
11-
Alumin refractory materials
12-
Oxide refractory materials
General definition of
refractory materials: the refractory fireproof materials
are metal or semimetal oxide which have a high melting
point and are consumed in the shape of brick, powder and
shaped pieces. They are applied as protecting layer in
the walls of the stove, reservoirs, bonkers, and in the
dishes by which the heated and melted materials are
transported. These materials will be substituted with
new materials which are materials used in steel
manufacturing. Nowadays the refractory materials are
abundantly used in various industries especially in
steel and ceramic manufacturing and all of the
industries in which the production process involves high
temperatures. Metallurgical industries of glass and
ceramic nuclear industries energy production industry,
and chemical industries are all in need of refractory
materials. All refractory materials have plastic point
of above 1520 degrees C. their role is to protect those
containers which are place for those reaction or
operation of high temperature. The said reactions or
operations ore the physical and chemical reactions of
iron or steel, non-Ferro industries, foundry operation,
glass and ceramic productions, also those in power
generators, atomic reactors, cement and lime industries
and industrial stoves.
The important
specifications of refractory materials are:
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Resistant against slag
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Highly resistant against heat shocks (sudden contraction
or expansion)
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Having physical rigidity against reheating
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Heat expansion
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Having heat conductibility
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Porosity and density
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The ability to penetrate (against gases)
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Shock resistant
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Creeping
Now the refractory
materials play an active role in the production of the
new generation of bio-ceramics.
Note:
Presently, having a
share of more than 1% of the global production of
refractory materials, Iran stands first among other
countries in the Middle East. Considering in the global
growth of steel industry of Asia and the Middle East,
the C.C.M ASIA group, is ready cooperate with large
foreign and domestic companies. It is also ready for
strategic cooperation with major foreign partners to
provide some refractory materials required for Iran’s
domestic industries. At present the company has several
research projects jointly administered with some
domestic companies and it is hoped it can play an
important role in international markets interactions.
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