Silicon Carbide Heaters (SiC, up to 1600°C) and Molybdenum
Disilicide Heating element (MoSi2, up to 1850°C)
Product advantages:
A. It has anti- oxidation and automatic repair function and can be
used continually in oxidative atmosphere.
B. We are using thermal processing in shape, which maintains a very
good high-temperature tenacity and plasticity of the basic
materials. Besides the products in the standard size and geometric
shape, we can also produce special shape and size products
according to the requirement from customers so as to meet their
demands of various installments.
C. In the cold and hot end welding aspect, it uses special joint
technology to take shape. Therefore, the welding point is fast and
strong anti-impact. No damage caused by caused by the impact of
current during the in and outage .no rupture caused by installation
D. The product has high density that greatly improves the
conductivity of the product. Our products are warming faster, lower
consuming lower than the products of other manufacturers, and then
save energy and costs.
E. good surface quality, high mechanical strength and toughness.
Products catalogue
| classification | name | distinction criterion | specification | trading limits |
| Heating elements | 1700 type | Element operating temperature 1700℃ is acceptable | LeΦ 6-12W type/U type/L type/all kinds of heterotype / stripe shape | high temperature electric resistance furnace |
| 1800 type | Element operating temperature 1800℃ is acceptable |
| 1800J type | Element operating temperature≥1800℃ | LeΦ 3-12W type | Special,high temperature and high-power electric resistance furnace |
| 1800T type | Element operating temperature≤1800℃ | LeΦ 3-12W type U type | Not oxidized special air high temperature electric resistance
furnace |
| Thermocouple protecting tube | standard type | Element heat- resisting temperature≤1700℃ | Producing all kinds of inside and outside diameter according to
customers’ need | Thermocouple whose temperature under 1500℃ |
| High temperature | Element heat- resisting temperature≤1800℃ | Producing all kinds of inside and outside diameter according to
customers’ need | Thermocouple whose temperature under 1700℃ |
| cracker pipe | Glass making kiln tube | Distinguish by simple pore diplopore and porous pore | Length and aperture is optional | Glass kiln |
| MoSi2 powder | initial powder | Purity ±98% granularity0.4－4um surface area7.8㎡/ cm | Modulate granularity according to customers’ demand | All kinds of spare parts of MoSi2 emery cloth, grinding wheel, other ceramics as well as additive |
| Ceramic powder | Purity ±90% | Modulate granularity according to customers’ demand |
Physics characters
| Bulk density | Bending strength | Hardness | Apparent porosity | Drawing water rate | Thermal elongation rate | Fracture toughness | Compressive Strength |
5.8g/ cm3 | 350MPa | 12.0GPa | ±2% | 0 | 4% | 4.5MPa.m1/2 | 650MPa |
Chemical property
Ant-oxidation in high temperature atmosphere: When MoSi2 bar is
used in the high temperature and oxidative atmosphere; it will form
a compact SiO2 protecting film in its surface to prevent its
continuing oxidized. When the temperature of element is over
1700℃,the SiO2 protecting film whose melting point is 1710℃ will be
melted. Due to the surface tension, SiO2 agglomerate into drops and
lose protection. The SiO2 protecting film is formed again when the
element continues to be used under the oxidative atmosphere.
It must be pointed out is that the MoSi2 heating element can not be
used in the temperature between 400℃ to 700 ℃ for long time.
Otherwise, the element will be pulverized because of the
low-temperature oxidation.
Main performance index
Atmosphere influence on the operating temperature of element
| Atmosphere | The max element temperature(℃) |
| | 1700type | 1800type |
| Air | 1700 | 1800 |
| N2 | 1600 | 1700 |
| He Ar Ne Argon, Helium | 1600 | 1700 |
| Dry Hydrogen(dew point) -80℃ | 1150 | 1150 |
| Wet Hydrogen(Dew point) -20℃ | 1450 | 1450 |
| mixed gas(e . g . 10%CO2, 50%CO, 15% H2) | 1600 | 1700 |
| mixed gas(e . g . 40%CO2 , 20%CO) | 1400 | 1450 |
| Cracked and partly burnt ammonia | 1400 | 1450 |
Resistance characters
MoSi2 elements have good resistance characteristic. This is the
deciding factor that it can replace conventional heating elements
to be an ideal heating material. Its resistivity is very low in the
greenhouse. As the temperature rises, the resistivity increases
rapidly. Therefore, it is self-evident that the product has rapid
temperature increment and low power expenditure. In normal
operating circumstances, the elements resistances is not changing
along with the length of time changes ,so the old and new elements
can be mixed.
Product use and maintenance
1. MoSi2 heating elements belong to Metal ceramic material. They
are hard, crisp and low impact strength at room temperature
.Therefore to be careful to avoid damage during transport and
installation.
2. When MoSi2 elements continue use under the oxidative atmosphere,
the surface temperature of 1700 type should not exceed 1700 °
C,1800-type should not over 1800 ℃ and when intermittent use,1700
type-element should not over 1650 ° C,1800type-element can not
exceed 1750 ℃.
3. The MoSi2 heating element should avoid using in the temperature
between 400℃ to 700 ℃ for long time. Otherwise, the element will be
low-temperature oxidized because of the adverse temperature
condition.
Furnace dryness
New or old furnace not used for a long time needs to be dry before
the use. Generally, the drying temperature is 100-200℃.However, if
the element is used for a long time under the low temperature, it
will cause the low-temperature oxidation. For the little furnace,
the drying time is short, so the influence of several drying hours
is little, but the large furnace need to be dry for a long time,
you had better open the furnace door to ventilate well. you can
open the furnace door ajar with the temperature increment and
completely close until the temperature reach 1000℃ above.
Furnace start
If the furnace dry out has been completed or does not need drying,
it has to rise its temperature. In order to avoid the over sized
electric current impact and cause the electrical equipment
overload; please go up the furnace temperature according to the
next table.
| Small furnace (power100KW) | Large furnace(Power 100-500KW) |
| Furnace temperature | Voltage | furnace temperature℃ | Voltage |
| 20-150 | 1/3Operating Voltage | 200-300 | 1/3Operating Voltage |
| 150-500 | 2/3Operating Voltage | 300-700 | 2/3Operating Voltage |
| 500-operating temperature | The Whole-Operating Voltage | 700-Operating temperature | The whole-Operating Voltage |
It should not take a long time when shifting gears. Otherwise it
easily causes the electric current shocking to break the electrical
equipment.
Element Replacement
If there is a damaged part found in the process of operation, the
first thing you should do is determine its location and get all the
combination elements ready. After that, you should separate the
wire the damaged element clipped to from the screw which is
connected to the generatrix. Then remove the remained refractory
wool and pull out the refractory stoppers. Insert the new
combination elements into the furnace from its roof. Connect all
the wires and get the refractory wool filled, and finally raise the
temperature.
