After: On November 9, 2015, it was difficult to press and release the A-phase electrode of the silicomanganese furnace. The day shift was stopped at 11:43-12:56 to process the A-phase electrode press and release. At the same time, 700 mm of the A-phase electrode was lowered for baking. On the 9th, the day shift was On the 10th, one furnace of iron was discharged from the night shift. After the night shift, the A-phase electrode was found to have a bright mark 1 meter below the copper tile at about 12:40. Then the material was returned and buried to continue smelting. The A-phase electrode was removed from the copper tile at 1:20 The bright mark is hardly broken, and then the power failure tissue pulls out the electrode to turn around and the A phase electrode below is 1200 mm, and the power is sent at 3:07 to continue roasting.
Reason analysis: the power outage on November 9 (11:3-12:56) was difficult to deal with the A-phase electrode pressing method. After cleaning, the pressing method still cannot be performed. During the repeated pressing and discharging of the electrode, due to the poor fixing effect of the electrode furnace top positioning device, The offset of the electrode causes the electrode to produce invisible cracks during the pressing and release. The electrode is not eliminated during the firing process, and the cracks are left after sintering and forming, which is the main reason for the hard fracture of the electrode.
The lower electrode is partially oxidized (the electrode is hardly broken), and a groove is formed (50-60 cm long and 15 cm wide). After the load is increased, the current gradually increases, and the oxidized part cannot withstand the current.
The secondary cause of hard electrode breakage.
Precautions:
(1) Reduce the number of hot shutdowns and make a plan for the next maintenance to fix the A and B phase electrode positioning devices to reduce electrode displacement deviation.
(2) When the furnace is hot shut down, enclose the exposed electrode with charge and wrap it with a dust-removing cloth bag; during the electrode roasting process, observe and lower the furnace door in time after receiving the material to prevent the electrode from oxidizing to the greatest extent.
(3) During the electrode baking process, according to the sintering situation of the electrode, the displacement of the baking phase electrode is tracked, and the baking phase electrode material is collected frequently to prevent the direct burning of the charge and increase the damage of the electrode.