Silicon carbide heating elements are high-temperature non-metallic electric heating components in rod or tube form, manufactured from high-quality green silicon carbide as the primary raw material through processing, billet formation, high-temperature siliconization, and recrystallization. Compared to metal heating elements, they offer advantages such as high operating temperatures (up to 1500°C), oxidation resistance, corrosion resistance, long service life, minimal deformation, and ease of installation and maintenance. Silicon carbide rods are available in various models, including thick-end and equal-diameter types, and styles such as straight rods, U-shaped rods, three-phase rods, five-section rods, grooved rods, single-thread rods, and double-thread rods, with diameters ranging from Φ8 to Φ54mm. These products can be used in atmospheres like air or vacuum as high-temperature electric heating elements in industries such as ceramics, magnetic materials, glass, metallurgy, powder materials, rare earth chemicals, electronic components, metal processing, refractory materials, and research institutions.

        Wiring methods for silicon carbide rods: If the resistance values of the elements differ, connecting them in series may cause concentrated load on the rod with higher resistance, leading to rapid resistance increase and shortened lifespan. Silicon carbide rods are typically wired using a combination of series and parallel connections. It is recommended to connect two rods in series as a group and then connect multiple groups in parallel. Particularly when the furnace temperature exceeds 1350°C, parallel connection is essential. For three-phase wiring, an open delta connection is advised. Practical experience shows that higher load density results in a greater temperature difference between the heating element surface and the furnace chamber. Higher load density also leads to elevated surface temperatures on the rods, faster resistance increase, and shorter element lifespan. Therefore, the surface temperature load, density, furnace atmosphere, and temperature are directly proportional to the aging rate of the elements and inversely proportional to their service life.

        Silicon carbide elements generally have a longer lifespan in continuous kilns compared to intermittent kilns. This is because during use, the surface oxidizes to form a silicon dioxide film, which thickens over time, increasing resistance. The silicon dioxide film undergoes abnormal expansion and contraction near the crystallization critical point (270°C). In intermittent kilns, where usage fluctuates around this temperature, the silicon dioxide film is repeatedly damaged, accelerating oxidation. Consequently, frequently cooling the furnace to room temperature rapidly increases resistance, shortening the element's service life.