Silicon carbide rods are prone to fracture due to severe vibration and impact

Precautions for using silicon carbide rods
1. Silicon carbon rods have a hard and brittle texture, and are prone to breakage when subjected to severe vibration and impact. Therefore, special care should be taken during transportation and handling with care.
2. The length of the heating part of the silicon carbide rod should be equal to the width of the furnace. If the heating part extends into the furnace wall, it is easy to burn the furnace wall.
3. The length of the cold end of the silicon carbide rod should be equal to the thickness of the furnace wall plus the length of the cold end extending out of the furnace wall. The extended length of the cold end is generally 50-150mm, in order to cool the cold end and connect the fixture.
4. The inner diameter of the furnace for penetrating silicon carbide rods should be 1.4-1.6 times the outer diameter of the cold end. If the furnace hole is too small or the filling material inside the hole is too tight, it will hinder the free expansion and contraction of the silicon carbide rod at high temperatures, leading to rod breakage. When installing, the silicon carbide rod should be able to rotate freely 360 degrees.
5. The distance between the silicon carbon rod and the heated object and furnace wall should be greater than or equal to 3 times the diameter of the heating part. The center distance between the silicon carbide rod and the silicon carbide rod should not be less than 4 times the diameter of its heating part.
6. The cold end of the silicon carbon rod is connected to the main circuit using aluminum braids or aluminum foil. The fixture at the cold end should be tightened.
7. Newly built furnaces or electric furnaces that have not been used for a long time should be dried before use, and old rods or other heat sources should be used for drying.
8. Silicon carbide rods should be stored to prevent moisture. Because moisture can easily cause the aluminum layer at the cold end to decompose and fall off, resulting in an increase in the contact resistance between the cold end and the fixture, and the silicon carbon rod is prone to cracking after being energized.
9. Silicon carbon rods need to be impedance matched before use. Connect silicon carbon rods with the same or similar resistance values together first.
10. Equip the silicon carbide rod with a voltage regulating device. At the initial stage of power transmission, the voltage is half of its normal working voltage, and gradually increases after stabilizing for a period of time. This way, the silicon carbide rod will not break due to rapid heating.
11. Long continuous service life of silicon carbide rods; Short intermittent service life.
12. When using silicon carbide rods, it is necessary to choose a reasonable surface load density and usage temperature. The operating temperature should not exceed 1650 ℃; When used in harmful gas environments, it is more important to prevent chemical reactions between silicon carbide rods and harmful gases.
13. When replacing silicon carbide rods, silicon carbide rods with a resistance similar to that of the silicon carbide rods running in the furnace should be selected. If necessary, the entire furnace of silicon carbide rods should be replaced, which is beneficial for improving the service life of the silicon carbide rods. If the resistance value is appropriate, silicon carbide rods that cannot be unloaded can also be replaced for use in the middle and later stages of electric furnace operation.
14. Prevent the silicon carbide rod from splashing molten metal, which can easily lead to rod breakage.
15. Prevent alkali, alkaline earth metal and basic oxide from corroding the silicon carbide rod.
16. Frequently observe whether the readings of ammeter, voltmeter and thermometer are normal; Whether the cold end fixture is loose, oxidized, blackened, or ignited; Whether the silicon carbide rod is broken; Whether the red heat at the heating part of the silicon carbide rod is uniform.