Maintenance of Zinc Smelting Induction Furnace
Because the Zinc smelting induction furnace has the advantages of high thermal efficiency, fast heating speed, less metal burning loss, less environmental pollution, easy operation, good working conditions, high power factor of electric furnace, low melting cost, the furnace is widely used in the smelting and casting section of zinc smelters. Among them, the inductor is the heating unit of the cored induction furnace, which is the heart of the induction furnace. Its performance, reliability and service life are directly related to the normal operation of the electric furnace equipment and the continuous and stable production of the zinc smelter.
So, how to carry out routine and daily maintenance of induction furnace?
1.Air cooling system
Since the air cooling system is used to cool the inductor, its work condition will affect directly its service life, and further more, insufficient air rate will cause damage of inductor due to over temperature, but additional air rate may prevent accident from getting worse by condensing the leaked zinc in case zinc leakage of the inductor is found. Therefore, good maintenance of the air cooling system is of great importance.
Every day: check if connectors are durable and fasten.Check if fan operation is normal and start the standby one if not, then repair the failed one as soon as possible.
Every day: take good records and compare them with glass thermometer, and calibrate thermal resistance thermometer if any deviation found.If air temperature is abnormal high or smoking is visible,cut power then check if zinc leakage or coil is burned-out exist.replace the broken parts.
2.Electric equipment
Electric equipment is for power supply and control of the electric furnace, any abnormal operation of them will directly affect work efficiency and service life of the furnace.
Every day: check if data from instruments in the control cabinets abnormally fluctuate and find out causes and regulate or repair the abnormal if any. Check if each major electric element and regulator is hot, and their sound and vibration abnormal, and regulate and repair them at once if any.
Every week: check if electric alarm and interlocking system operate correctly and automatic switch and contactor work normally.
Every month: check if electric devices are reliably grounded and electric connection bolts durable.Eliminate dust accumulated on busbar and capacitors (shall be carried out when power is cut off).
Every year (or shut down for maintenance):Check if value of insulating resistance(including voltage regulator and capacitor) between all energized elements and grounded metal structures is ≥1MΩ. Check if availability of all electric elements’ contactors and movable elements is good and replace them if not.
3.Furnace body
a. Every day: check if there is any paint dropping resulted from zinc leakage of the furnace surface and furnace shell abnormally changed in shape.
b. Every month: check if the furnace is connected well with grounded grid and clean out slag accumulated on furnace wall and cover.
c. Every year (or in overhaul): check if furnace liner seriously broken and rebuilding is necessary.
4.Inductor
Since inductor is the most critical part of the zinc smelting furnace, its maintenance and repair are of great importance.
4.1 Maintenance
Every day: check if inductor noise is louder and fasten screws of the tension unit if it is. In case nuts fastening provides no efficiency, short term power off is necessary to lift out iron core, coil and fasten nut of fixing coil. Check cooling air temperature and keep it normal. Check if there is any zinc leakage form the inductor and ready to replace the abnormal and remove blockages at throat by special tools.
Every month: check if channel pattern is blocked or eroded so as to avoid zinc leakage. Test insulating resistance between iron and coil, coil and shell by megger so as to keep it at above 1MΩ level.
Every year: replace the iron core and coil with spare parts,and check carefully the replaced one to find out any hidden troubles and eliminate them.
4.2 Repair
Shell repair: repair the damage by riveting welding, shaping and machining, and repaint them and keep them in perfect condition.
Coil repair: replace the damaged insulators or screw bolts and gaskets as per the provided drawing for spare parts. These replaced shall be shaped, repainted and baked. Coil with its copper wire seriously burned shall be discarded.
Iron core repair: replace the damaged insulators or double-thread screw as per the provided drawings for spare parts. In case the silicon steel sheet is seriously damaged, the iron core shall be discarded.
Post time: May-06-2024