Sic Heating Elements Description
SiC heating elements are usually used as high temperature furnace
heaters or kiln heaters. Working temperature is 600°C-1500°C.SiC
heating elements are non-metal electric heating element made from
SiC as its main raw material.
Sic Heating Elements Advantages
- High purity raw materials;
- High structural density;
- Slow aging;
- Maximum temperature being up to 1500℃ (2732°F);
- Easy to be installed and replaced.
Types and Applications of Sic Heating Elements
1. SW (Standard)
SW Silicon Carbides are used in applications ranging in temperature
from 600°C up to 1400°C in both air and controlled atmospheres.
Although the type of atmosphere used will determine the maximum
recommended element temperature. This kind of silicon carbide
elements can be mounted either vertically or horizontally.
2. U-TYPE
U shape Silicon Carbide is consists of two silicon carbide rod with
same diameter. Each rod has both hot zone and cold end with
identical resistance. Two rods are connected by the low resistance
SiC. Also the connector could be used as holder according to
different requirements.
3. W-TYPE
3-phase elements are available in 2 different types: SGC
(Dumbbell), SGD(Standard).
These elements are self-bonded silicon carbide formed by
re-crystallization of silicon carbide at high temperature. It
consists of three high-purity silicon carbide rods connected at one
end by a silicon carbide crossbar. SGC elements are designed for
vertical installation in standard float glass bathes and SGD
elements for horizontal installation. They can be connected
directly on three-phase power supply and is a one-side terminal
type which permits drawing out the terminals from the roof of the
furnace.
4. Single Spiral Silicon Carbide and Double Spiral Silicon Carbide:
They are made from silicon Carbide powder, and have two shapes:
single and double sprial silicon carbide heating element. They are
widely used in all kinds of kilns and furnaces.
Physical property of SIC heating element
specific gravity | 2.6~2.8g/cm³ | bend strength | >300kg |
hardness | >9MOH’S | tensile strength | >150kg/cm³ |
porosity rate | <30% | radiance | 0.85 |
Recommended surface load and Influences to Surfaces of the Elements
in Different Operating TemperatureS
atmosphere | Furnace Temperature(°C) | Surface Load(W/cm2) | The influence on the Rod |
Ammonia | 1290 | 3.8 | The action on SiC produces methane and destroys the protection film
of SiO2 |
Carbon dioxide | 1450 | 3.1 | Corrode SiC |
Carbon monoxide | 1370 | 3.8 | Absorb carbon powder and influence the protection film of SiO2 |
Halogen | 704 | 3.8 | Corrode SiC and destroy the protection film of SiO2 |
Hydrogen | 1290 | 3.1 | The action on SiC produces methane and destroys the protection film
of SiO2 |
Nitrogen | 1370 | 3.1 | The action on SiC produces insulating layer of silicon nitride |
Sodium | 1310 | 3.8 | Corrode SiC |
silicon dioxide | 1310 | 3.8 | Corrode SiC |
Oxygen | 1310 | 3.8 | SiC oxidized |
Water-vapor | 1090-1370 | 3.1-3.6 | The action on SiC produces hydrate of silicon |
Hydrocarbon | 1370 | 3.1 | Absorb carbon powder resulted in Hot pollution |
Notice for using and installing:
1. Heater should be protected against damp during storing or
installing to ensure the performance of the heater.
2. In order to be sure of well-distributed lod of each and groups,
heater should be divided before assembling. The tolerance of the
resistance of each one cannot exceed by 10% each other.
3. Heater is hard and brittle, please be careful when assembling
and maintaining so as to avoid damage.
4. When operating the electric furnace at the beginning, the
voltage should be increased slowly and cannot be fully loaded at
once. Otherwise the larger current will be resulted in the damage
of heater.
5. When heater is damaged and need to be changed, the resistance of
new one should follow the increasing resistance. If many are
damaged or resistance increased too much, heater should be changed.
Quality control:
