Reaction Bonded Single Spiraled Heating Elements
Ultra-Spiral Elements are made from thin-walled tubes of Alpha Silicon Carbide, which are highly dense and resistant to oxidation. The heating elements are usually spirally cut to increase the resistance of the hot zone. These spirally cut ends provide the resistance ratio to make the hot zone hotter and cold zones cooler. The elements are made to be wired at both ends. To provide a low resistance contact surface, the ends are metallized. Spring clamps and flat aluminium braids are used to make the connections at the ends.
Ultra-Spiral Elements being a thin-walled, fine grain form of reaction bonded Silicon Carbide, will withstand very rapid heating and cooling cycles, severe thermal shocks, and high electrical loadings. There are no restrictions to the mounting position of the Single Spiralled heating element. The most common positions are horizontal and vertical. Precaution must be taken so that the heating elements are not mounted in tension. Since the elements expand and contract independently, adequate allowance must be given for them to do so. The heating sections of the heating elements must be centred in the furnace section so that there is no section extending into the furnace wall.
The Single spiral elements can be replaced easily even when the furnace is at operating temperature. Silcarb ultra Spiral elements gradually increase in resistance with use. This characteristic is also known as aging. The Ultra Spiral elements reach temperatures of 1650° C in an inert atmosphere of helium or argon. With reducing atmospheres, the maximum operating temperatures are 1371° C. Ultra-Spiral Elements operate in most industrial and laboratory Furnaces at temperatures up to 1600oC.
The Ultra Spiral Heating Elements manufactured by Silcarb are interchangeable with all the standard Single Spiralled Silicon Carbide heating elements manufactured by different countries around the world.
The Ultra Spiral range of elements is available in different product forms and can be customised to different standard sizes and geometries to suit a variety of heating processes. Contact us for any further details.
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