Silicon carbide is a resistance type heating element.and made from high density reaction-bonded silicon carbide or high purity recrystallized silicon carbide , that are extruded in the form of rods or tubes, before being bonded together by a process of re crystallization, at temperatures of over 2500°C (4530°F). The firing process ensures the creation of rods with strong uniform bonds between adjacent grains, and the particle size distribution is closely controlled to ensure optimum density and resistance to the process atmosphere.
Heating elements for element temperatures up to 1625°C (2927°F), available in a wide variety of standard sizes and geometries, or in customized designs to meet the specific needs of various processes and equipment. heating elements are capable of high power output, and may be mounted either vertically or horizontally. no special supports are required.
Grade 1 QS1
SiC heating Elements suitable for most applications in which silicon carbide elements are used. heating elements feature hot zones of high purity recrystallized silicon carbide, optimized for resistance to oxidation and common process gases. Available in rod or multi-leg designs. high density -- approximately 2.52 g/cm3 or 2.7g/cm3 to 2.8 g/cm3.This gives the Starbar very slow aging characteristics and high strength
Grade2 QS2
SiC heating elements designed for the most challenging applications where conventional silicon carbide elements are unsuitable. SiC heating elements feature hot zones of high density, low permeability, reaction-bonded silicon carbide, which is highly resistant to oxidation, and to chemical attack by process volatiles and reactive atmospheres. At 2.7 g/cm3, this high-density low-porosity element has an extremely slow aging characteristic and made of high density recrystallized silicon carbide, these multiple leg sic heating elements use the same hot zone and cold end material as the DH&DL type and offer a configuration that allows the electrical connections to be made at one end. The low resistance terminal ends allow for cool operation. The LRE (low resistance ends) have a high (15:1) electrical resistance ratio to the hot zone section. The first several inches of the cold ends are metallized with aluminum to provide a low electrical resistance contact surface. The electrical connections are made using flat aluminum braids held in compression to the circumference by a stainless steel spring clamp. U type sic heating elements are described by giving the overall length, the heating section length, the cold end length and the diameter
Item # | Item Name | QS leg Diameter | Ohms per Leg Hot Zone | Ohms per Leg Cold End |
U-1/2-13 | U-Mulitiple Leg QS,Silicon Carbide Heating Element | 1/2 Inch
13 mm | 0.1963 Ohms/Inch
0.00773 Ohms/mm | 0.00982 Ohms/Inch
0.000387 Ohms/mm |
U-5/8-16 | U-Mulitiple Leg QS,Silicon Carbide Heating Element | 5/8 Inch
16 mm | 0.1262 Ohms/Inch
0.00497 Ohms/mm | 0.00631 Ohms/Inch
0.000248 Ohms/mm |
U-3/4-19 | U-Mulitiple Leg QS,Silicon Carbide Heating Element | 3/4 Inch
19 mm | 0.0865 Ohms/Inch
0.00341 Ohms/mm | 0.00433 Ohms/Inch
0.000170 Ohms/mm |
U-1-25 | U-Mulitiple Leg QS,Silicon Carbide Heating Element | 1 Inch
25 mm | 0.0500 Ohms/Inch
0.00197 Ohms/mm | 0.00250 Ohms/Inch
0.000098 Ohms/mm |
U-1-1/4-32 | U-Mulitiple Leg QS,Silicon Carbide Heating Element | 1-1/4 Inch
32 mm | 0.0343 Ohms/Inch
0.00134 Ohms/mm | 0.00171 Ohms/Inch
0.000067 Ohms/mm |
U-1-1/2-38 | U-Mulitiple Leg QS,Silicon Carbide Heating Element | 1-1/2 Inch
38 mm | 0.0234 Ohms/Inch
0.00092 Ohms/mm | 0.00117 Ohms/Inch
0.000046 Ohms/mm |
U-1-3/4-44 | U-Mulitiple Leg QS,Silicon Carbide Heating Element | 1-3/4 Inch
44 mm | 0.0165 Ohms/Inch
0.00065 Ohms/mm | 0.00082 Ohms/Inch
0.000032 Ohms/mm |
4-2-1/8-54 | U-Mulitiple Leg QS,Silicon Carbide Heating Element | 2-1/8 Inch
54 mm | 0.0150 Ohms/Inch
0.00059 Ohms/mm | 0.00075 Ohms/Inch
0.000030 Ohms/mm |
Physical properties
Bulk Density | 2.5g/℃m3 |
Porosity | 20% |
Thermal Conductivity | 14-19w/m ℃ |
Rupture Strength | 50Mpa(25℃) |
Specifi Heat | 1.okj/℃(25-1300℃) |
Coefficient of Thermal Expansion | 4.5x10-6(1000℃ |
OPERATING TEMPERATURES
SLIOCON CARBIDE HEATING ELEMENT USE BY ATMOSPHERE |
ATMOSPHERES | TEMPERATURE LIMIT | MXXIMUM LOADING W/in2 | MXXIMUM LOADING W/cm2 | EFFECT |
CLEAN DRY AIR | 1150℃ | Maximum | Maximum | One piece Sic element can be operated at furnace control temperatures up to 1600ºC. (Maximum element temperature is 1625ºC). The three-piece Sic element is limited to 1427ºC. |
HYDROGEN
DP+75°F
DP-60°F | 1300℃
1300℃
1093℃ | 30
30
30 | 5
5
5 | An atmosphere which contains any percentage of hydrogen whatsoever will react with silicon carbide if the temperature exceeds 1300ºC. |
AMMONIA | 1300℃ | 30 | 5 | Reduces silica film, Frorm CH4 from Sic |
NITROGEN | 1370℃ | 30 | 5 | Form insulating Silicon Nitrides |
PURE OXYGEN | 1315℃ | 25 | 4 | Faster oxidization than in air. Use LMA infusion glaze cotated starbar elements, or type TW, SE,SER or SEU |
CO2 | 1500℃ | 25 | 4 | No effect,may deposit Carbon |
CO | 1540℃ | 25 | 4 | No effect |
ARGON/HELIUM | 1700℃ | Maximum | Maximum | No detrimental effect |
WATER DP 60°F
50°F
0 °F
-50 °F | 1095℃
1200℃
1370℃
1540℃ | 30
45
40
45 | 5
5.5
6.5
7 | Reacts with Sic to form Silicon Hydrates ,Use LMA infusion glaze coated Starbar elements, or type TW,SE,SER,or SEU. |
HALOGENS | 700℃ | 25 | 4 | Attacks Sic and SiO2 reducing |
HYDROCARBONS | 1315℃ | 20 | 3 | Hot spotting from C pick-up |
METHANE | 1315℃ | 20 | 3 | Hot spotting from C pick-up |
DRY EXOTHERMIC GAS | 1400℃ | Maximum | Maximum | Dependent on composition |
DRY ENDOTHERMIC GAS | 1250℃ | Maximum | Maximum | Dependent on composition |
VACUUM | 1205℃ | 25 | 4 | To 7 Microns -Below vaporizes Sic. Short term use only |
S and SO2 | 1315℃ | 25 | 4 | Attack Sic |
CUSTOM CONFIGURATIONS
Special sizes and shapes are available. Cold ends can be different lengths. This, for example, would be applicable for furnaces with arched roofs that require longer cold ends through the roof and shorter through the floor. Another modification is a multiple-temperature hot zone. This, for example, would be helpful to get additional heat energy into the lower, more densely loaded tunnel kiln. While this special modified hot zone may not create a specific temperature differential, it does offer a convenient way to get more or less heat energy.
SUPERIOR PERFORMANCE
SIC elements will give you superior performance due to their high density -- approximately 2.52 g/cm3 .or 2.7 g/cm3to2.8 g/cm3 ,This gives the SIC elements very slow aging characteristics and high strength.
Ordering
The minimum information required when ordering QS SIC elements is as follows:
Element type:
Diameter, mm (ØA)
Hot zone length, mm (B)
Cold end length, mm (C)
Leg center distance, mm (D)
Slot position* (E)
Nominal resistance, Ω
