Precautions for the use of silicon carbon rods

1. The texture of silicon carbon rod is hard and brittle, and it is easy to break when subjected to severe vibration and impact. Therefore, it is necessary to take extra care when transporting and handle it gently.

2. The length of the heating part of the silicon carbon rod should be equal to the width of the furnace. If the heating part sticks into the furnace wall, it is easy to burn the furnace wall.

3. The length of the cold end of the silicon carbon rod should be equal to the thickness of the furnace wall plus the length of the cold end extending out of the furnace wall. Generally, the extension length of the cold end is 50~150mm, so as to cool the cold end and connect the fixture.

4. The inner diameter of the furnace wearing the silicon carbon rod should be 1.4~1.6 times of the outer diameter of the cold end, and the furnace hole is too small or the filling in the hole is too tight, which will hinder the free expansion and contraction of the silicon carbon rod at high temperature and cause the rod to break. When installed, the silicon carbon rod should be able to rotate 360 degrees freely.

5. The distance between the silicon carbon rod and the heated object and the furnace wall should be greater than or equal to 3 times the diameter of the heating part. The center distance between the silicon carbon rod and the silicon carbon rod should not be less than 4 times the diameter of the heating part.

6. The cold end of the silicon carbon rod is connected with the main circuit with aluminum braid or aluminum foil. The clamp at the cold end should be clamped tightly.

7. The new furnace or the electric furnace that has not been used for a long time should be baked before use, and the old rod or other heat source should be used to bake.

8. Prevent moisture when storing silicon carbon rods. Because it is easy to decompose and fall off the aluminum layer of the cold end after being wet, the contact resistance between the cold end and the fixture increases, and the silicon carbon rod is easy to crack after being energized.

9. The silicon carbon rod should be matched before use. Silicon carbon rods with the same or similar preresistance value are connected together.

10. Equip the silicon carbon rod with a voltage regulating device. The initial voltage of power transmission is half of its normal working voltage, and the voltage is gradually increased after a period of stability. In this way, the silicon carbon rod will not break due to the rapid increase in heat.

11. The silicon carbon rod has a long continuous service life; Short intermittent service life.

12. When using silicon carbon rods, it is necessary to choose a reasonable surface loading density and use temperature. The operating temperature should not be greater than 1650°C; When used in a harmful gas environment, it is necessary to prevent the chemical reaction between the silicon carbon rod and the harmful gas.

13. When replacing the silicon carbon rod, the silicon carbon rod should be selected close to the resistance of the silicon carbon rod running in the furnace, and the silicon carbon rod of the whole furnace should be replaced if necessary, which is conducive to improving the service life of the silicon carbon rod.

14. Prevent the silicon carbon rod from splashing molten metal, which can easily lead to rod breakage.

15. Prevent alkali, alkaline earth metal and alkaline oxide from corroding silicon carbon rod.

16. Always 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 carbon rod is broken; Whether the heating part of the silicon carbon rod is evenly red-hot.