It is a common phenomenon that graphite electrodes are broken in all electric furnace smelting, and it is also the most important factor affecting consumption. It is normal for continuous consumption and occasional breaks in a complex environment, but continuous breaks are not normal. The reason is related to many factors. The overall view can be divided into: artificial break and mechanical break. The artificial break mainly includes: bumping and scratching during lifting, improper connection or improper method, improper sliding in the flat holder, poor hardness of hard collision or transmission control. In addition to mechanical failures in mechanical breaking, electrode quality problems and operational problems are often present and difficult to distinguish. The main phenomena are as follows.
(1) Electrode body fracture phenomenon
First, the electrode may have structural defects and may have low strength; second, it is a short-arc operation after smelting, and there is a lateral impact force of a large collapse; third, the three-phase electrode on the furnace is not vertical and has a slag Or scraping the lid phenomenon. The sound is very brittle when broken.
(2) Breaking of the bottom of the electrode body
First, the electrode end structure is loose or has dark lines, the joint and the hole are not properly matched or the material difference linear expansion coefficient is not matched; the second is that the phase electrode is not concentric, the electrode stroke is too long or the lifting is not sensitive; the third is that the furnace fabric is unreasonable There is no conductive material under the electrode. When breaking, the sound is not big but the tilt is heavier.
(3) The joint is broken and irregular
First, the taper of the joint is different or the ellipticity of the joint is too large; the second is that the dust in the hole is too much, and the contact resistance is too large, so that the joint is too oxidized too quickly; the third is that the electrode is not in contact and the torque is not reached. The fourth is that the handle is tilted, and the electrode is not the same as the hole of the furnace cover. The sound is crisp and small when broken.
(4) The joint fracture is a regular phenomenon
It is the difference in the quality of the joint itself, the strength of the joint can not meet the demand of the smelting furnace; the second is the improper matching of the electrode hole and the joint tolerance or the connection torque can not reach the required kickback; the third is that the secondary current fluctuation range in the power supply is too large or there is Sudden increase phenomenon, the maximum instantaneous current is far more than 1.2 times of the rated value; Fourth, the thermal shock generated when the power and power are too large is too large, and the electrode joint is reddish and the resistance is too large. The sound is boring when broken.