Dongfang
Xinxing Refractories Co.,Ltd.
Subordinated to Dongfang Group,this company is
specialized in R & D,and manufacturing of insulating
bricks including fireclay based, high alumina based,
mullite based and silica based with density of
0.5,0.8,1.0 and 1.2 for glass and metalurgical
industries.Recently,a light weight mullite insulating
board has been developed to meet the requirement of
insulating of ladle and tundish.
Light-weight
mullite insulating board
1 Preface
Nowadays,
energy shortage and greenhouse effect are the foremost
and most pressing problems that face the world, and
energy conservation and pollution reduction are the
major measures that relieve the problem. Therefore,
energy conservation materials are adopted actively by
construction industry, traffic etc. As high temperature
industries, energy conservation and pollution reduction
are the most meaningful. Generally, refractory fibre
product, calcium silicate board, fireclay high alumina
mullite light-weight brick or bulk stuff as well as
corundum bubble are adopted as insulating linings used
in high temperature industry furnaces at present.
However, refractory fibre product is easily deformed by
extrusion and its service temperature is limited;
calcium silicate board is subject to pulverization
during the application and the service temperature is
low; fireclay or high alumina mullite light-weight brick
is characterized by low CCS and higher thickness (above
40mm in general); with high price, corundum bubble is
characterized by high B.D (above 1.4 in general) and
high thermal conductivity (＞0.9w/m·k).
Therefore, our company has developed a series of
light-weight mullite insulating boards，including
corundum based, bauxite based and firecaly based
insulating boards.
2. Main
characteristics of mullite light-weight insulating board
Ø
High RUL,
made of high purity materials, service temperature
reaching to 1600℃.
Ø
lower B.D,
about 1.2g/cm3 in general.
Ø
High CCS,
reaching to 16MPa, used to make light-weight insulating
board with thickness of 15-30mm.
Ø
High
porosity, above 60%, evenly distributed closed round
pores with size of 1-0.5mm.
Ø
Low thermal
conductivity, 0.4W/m·K
at 600℃.
With volume
stability, no deformation under high temperature
compression, the corundum based insulating board has
only 0.3% permanent linear change after holding for 3
hours at 1500℃.
Data sheet
of light-weight mullite insulating boards
|
|
|
RF-IBAM
Typical value |
RF-IBBM
Typical value |
RF-IBCM
Typical value |
|
Chemical composition, % |
Al2O3 |
72.28 |
71.56 |
50.82 |
|
SiO2 |
26.68 |
21.57 |
43.05 |
|
Fe2O3 |
0.13 |
1.35 |
0.86 |
|
TiO2 |
0.08 |
1.69 |
0.48 |
|
Bulk
density, g/cm3 |
1.05 |
0.98 |
0.92 |
|
Cold
crushing strength , MPa |
18 |
15 |
13 |
|
PLC,
% (1400℃，3h) |
-1.38 |
+0.28 |
-0.56 |
|
Thermal conductivity, W/m·K
at
800℃ |
0.612 |
0.416 |
0.294 |
3. Range of
application of corundum mullite light-weight insulating
board
High
temperature vessel of metallurgical industry and thermal
insulating of kilns and furnaces, such as ladle, tundish,
hot metal ladle etc.
4．
Application sample of corundum mullite light-weight
insulating board
The
product has been applied to a 300 tons ladle, whose
service life could compare to that of permanent lining,
keeping stable shape under high temperature, reducing
the cracks of permanent lining and working lining as
well as hot steel penetration, improving the safety of
ladle. The temperature of ladle shell could be compared
with the ladle lined with high alumina fiber board.
5. Product
shape
230×114×15（15~30）mm
230×114×15（15~30）mm/
each piece, could be made according to the customers’
requirements.
Mullite
based insulating board
