Foundry factories have their own practices, some cases are very special, according to their own actual situation to grasp. General regularity control should be based on the following characteristics and methods:
1. The power of the induction furnace is larger, that is, the power density is high, and the power required for a furnace of molten iron smelting in 50-60 minutes under normal conditions.
2. The general melting temperature should be controlled at 1500-1550 degrees. Because the casting temperature is low, but the maximum melting temperature is not allowed to below, the clean return charge can quickly reduce the temperature of molten iron when coming out of the furnace. Small pieces or specially required molten iron may be heated appropriately, but the disadvantages should be taken into full consideration. Very good pretreatment measures should be taken to increase the crystallization core of molten iron.
3. Hot metal in the furnace at 1500-1550 degrees, except for a short period of standing, to quickly come out of the furnace, do not leave the furnace for too long. If the capacity of the electric furnace is larger, the hot metal to be divided into multiple bags out of the oven, the correct way is: short pouring time, short waiting time in the hot metal furnace, strengthen the pretreatment; After a long pouring time, the same brand of clean return charge is added immediately to reduce the temperature in the furnace. When the empty bag comes back, the temperature is raised again, and the furnace is removed after pretreatment. This can reduce the hot metal retention time.
4. A large number of casting molding with coated sand technology, considering the prevention of porosity waste, some need very low casting temperature, but in most cases is to take a higher casting temperature, to solve the porosity defects, at this time to pay attention to, careful heating, fully do a good job of pretreatment, increase the core of molten iron graphite.
5. In most high-temperature smelting casting factories, the molten iron is poured for many times, resulting in the temperature decrease, which is made up by increasing the discharging temperature to ensure the final pouring temperature. This way can think of a way to reduce the number of inverted, and at the same time to repair the lining of the molten iron bag, to pay attention to some, to lay insulation layer inside the lining, firebrick, finally attached with carbon refractory layer, to reduce the temperature drop of molten iron in the bag.
6. The temperature of the molten iron is much lower when it is wrapped in cold water. Before coming out of the oven, the inner layer of the molten iron must be dried, hot and red. There is no way to the factory, you can consider the iron bag, to reduce the temperature drop of the iron bag.
7. Induction furnace smelting, there is a graphite core to reduce the characteristics, even the normal smelting of molten iron, it is best to do the pretreatment after coming out of the furnace, the pretreatment operation as a necessary operation to carry out the molten iron smelting.
