Xinhui Carbon technicians rushed to the scene immediately to inspect and analyze the cause and follow up on the smelting process.
Analysis:
- When the electrode is stressed, the degree of force decreases progressively from the top to bottom. The maximum stress is on the joint of electrode and nipple under the holder.
- When the electrode is subjected to external force: The external force of stress concentration > the strength of the electrode, and this will lead to the damage of the electrode.
- The causes of external force: the collapse of the big charging materials during the melting period, the non-conducting objects exist at the bottom of the electrode in the scrap steel, the impact of the nubby flowing steel.
- The causes of breakage:the incongruous response speed of the lifters, the deviated electrode the furnace cover holes from the core, the gaps between the joint of electrode and nipple and the unsubstandard nipples.
- Poor machining accuracy of electrodes and joints will also cause poor coordination and joint breakage.
Solution:
- The electrode phase sequence must be correct. In three-phase AC arc furnace, the electrode phase sequence should be counter-clockwise. If it was clockwise, the electrodes will be loose and to be damaged.
- In order to reduce the breakage and damage caused by mechanical force, inside material collapse and improper operation, the large steel material should be put in the lower layer of the furnace, and the scrapped steel should be evenly distributed in the furnace.
- Avoiding non-conductive materials are in scrap steel, do not allow non-conductive objects such as lime to accumulate directly below the electrodes, otherwise it would affect the electrification or break the electrode.
- Pay attention to the position of the furnace cover. The electrode pillar should be centered in the furnace top hole, and the electrode pillars should be parallel. The furnace roof should be cleaned regularly to avoid the electrodes being broken due to the accumulation of residual steel slag.