Why does graphite electrode break during EAF steel making process?

Due to the development of electric furnace steelmaking, the quality and specifications of graphite electrodes have also continued to improve. The normal use of graphite electrodes in the eaf steelmaking process is critical. For example, there are quality problems with graphite electrodes during the smelting process and improper smelting operations. All can lead to breakage.

Graphite electrode impact on the eaf steel making process process

Generally speaking, for high-quality graphite electrodes, under correct operation, its consumption in the smelting process is very small, accounting for about 1%-15% of the total consumption.

In this process, the current load and electric furnace operation method are very important, which can reduce the breakage rate of the electrode.

If the electrode breaks during the eaf steel making process, it will inevitably increase the smelting production cost.

If the quality of the graphite electrode is not high, the consumption will be too high and the smelting cycle will be lengthened.

At the same time, it may cause furnace shutdown and decrease in output.

Reasons in production

1. The holder is used improperly, cannot be kept perpendicular to the electrode, and the force is uneven.
2. The charge in the steelmaking furnace breaks the electrode. This is due to the impact of the arc.
3. The electromagnetic resonance in the AC arc furnace and the current during the smelting process generate a magnetic field. The resonance makes the electrode unbearable.
4. The graphite electrode falls and contacts the scrap steel. If it encounters obstacles during the arcing process, it will break directly.
5. The current output is unstable when there is a large collision between the electrode tip and the scrap steel.

Graphite electrode quality reasons

• The density and flexural strength indicators of graphite electrodes cannot be reached.
• If the resistivity is high, the nipple will heat up quickly during the power-on process, and if the electrode body has high resistance, the connection may break.
• When the volume density of the nipple is not high enough, its flexural strength will also be reduced, and it will easily break during use.
• If there are cracks inside the electrode, its thermal shock resistance will deteriorate.
• Choose the right grade RP, HP and UHP  graphite electrode for your eaf steelmaking process.

Precautions

The electrode holder should be clamped above the white line at the electrode connection; ensure the cleanliness of the nipple and use the spreader correctly; avoid falling materials or scrap steel from breaking the electrode; during the high-voltage power transmission process, the voltage balance and arcing situation should be ensured.

In summary

The steelmaking plant controls the standardized operation of the electric furnace, and the graphite electrode manufacturer controls the physical and chemical indicators of the product. The two cooperate with each other to achieve the highest production efficiency.