Four Precautions for Graphite Rod in Vacuum Furnace

The graphite rod is frequently used in high-temperature vacuum furnaces, where it serves as an electric heater and helps the oxidation of products at high temperature, making it easier to manufacture the suitable products. On the market, graphite rods are extremely popular. The primary reason is that it is cost-effective.

Thermal conductivity and electrical conductivity of the carbon graphite rod are very high. For example, the thermal conductivity of graphite rods is different from that of general metal materials. It is greater than iron, lead, steel, and other metal materials, and will increase with temperature as the coefficient of thermal conductivity decreases. Carbon graphite rods are four times as conductive as stainless steel and two times as conductive as carbon steel.

1. High Uniformity. When using a graphite vacuum furnace as an electric heater, it is necessary to select the red heat uniformity of the heating section, since this will affect temperature distribution and service life of furnace. When the graphite carbon rod is utilized with insufficient red heat uniformity, the graphite rod will shatter.

2. The higher the surface temperature, the shorter the service life of the graphite rod due to its composition. The oxidation rate will accelerate and the life span will be lowered if the surface temperature of the graphite rod surpasses a specific degree. As a result, we advise that you do not overheat the surface temperature when using it.

3. Give enough room for voltage adjustments. When graphite carbon rods are heated in the air, a protective layer of oxidation resistance forms on their surface. Then, for intermittent usage, we must ensure that the temperature in the vacuum furnace is stable, so that when we use a new graphite rod, the resistance of the graphite rod will increase at a lower voltage, which is advantageous.

4. Later stages of voltage. The voltage required at a later stage when employing numerous graphite rods will be higher than the voltage of the new rod. As a result, we must pay close attention to the later voltages and modify them in accordance with the regulating or wiring method, and the upper limit of the later voltages will be computed in general.