Silicon Carbide Heating Element, 1550 ℃
High Temperature SIC Heating Element Electric Heating Resistor for Furnaces
SIC Heating Element Description
Silicon carbide (SiC) Heating Element is a kind of non-metal rod or tube shape high temperature electric heating element.It is made of selected super purity green hexagonal silicon carbide as main material, which is made into blank and silicon crystal under high temperature of 2400ºC. In oxidizing atmosphere, its service temperature can reach 1450°C and continuous use life can reach 2000 hours.
SIC Heating Element Features
1. High strength and excellent shock resistance;
2. Heat source is free of noise and air pollution;
3. Anti-oxidization;
4. Anti-corrosion,
5. Long service life,
6. Little deformation,
7. Easy installation and maintenance.
8. Excellent specific rate of heat zone resistance and cold end resistance,
9. Avoiding over-temperature of cold ends to damage the furnace body.
10. Saving energy
Types and Applications of SiC Heating Elements:
There are ED, U, W, H, Gun, Single Spiral, Double Spirals, Dumbbel, Door-like types and etc. which are widely used in various high temperature electric furnaces in air, vacuum and other protection gas environments and other electric heating devices, such as industries of magnet, ceramics, powder metallurgy, glass and machinery, etc.
1. ED-TYPE
ED 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.
Normally the following should be given when describing any type of SiC heating elements:
· Type: ED, U, W, SC, SCR, DB,G, H, or DM
· Outside Diameter (OD) : mm
· Length of Hot Zone (HZ) :mm
· Length of Cold Zone (CZ) :mm
· Length of Overall(OL):mm
· Center Distance (A) :mm
· Resistance (at 1050℃+/-50℃) :Ω
Physical property of SIC heating element
| specific gravity | 2.6g/cm³~2.8g/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 |
